Benign diseases of the biliary tract are one of the most common surgical problems in the world. Gallstones affect millions of people in the West, while oriental cholangitis is common in the East. Surgery plays an important part in treatment: over half a million cholecystectomies are performed each year in the United States of America. New percutaneous techniques avoid the need for a conventional abdominal incision; they are playing an increasing role in treatment but a thorough understanding of the basic anatomy, physiology, and pathology of the biliary tract is required. Footnote 5

The liver and the biliary tract are derived from the foregut. The liver first appears in the 3-week embryo as a hollow endodermal bud from the distal foregut. This bud, the hepatic diverticulum, consists of rapidly proliferating cells that penetrate into the ventral mesogastrium. These cells eventually develop into the liver; the connection between the hepatic diverticulum and the foregut is preserved to form the bile duct. A ventral outgrowth of the bile duct gives rise to the gallbladder and the cystic duct. As the intestine rotates the entrance from the bile duct into the duodenum moves to a posterior position and the common bile duct comes to lie behind the duodenum and pancreas.

Within the developing liver the bile ducts are distributed in a segmental fashion. Bile is secreted by the liver cells into bile canaliculi. The canaliculi drain into ductules and on into larger segmental bile ducts which are tributaries of either the left or the right hepatic ducts. The left hepatic duct drains segments II, III, and IV; segments V, VI, VII, and VIII drain into the right hepatic duct. The caudate lobe (segment I) lies astride the inferior vena cava posteriorly and drains into both the right and the left hepatic ducts. This segmental anatomy of the liver and its ducts is important in liver and biliary tract surgery (Fig. 1) 1224 and is discussed in more detail in Section 22.1.

The right and left hepatic ducts join to form the common hepatic duct at the hilum of the liver. The confluence usually lies outside the liver itself and in front of the right portal vein. The left hepatic duct has a relatively long extrahepatic course on the posterior aspect of the quadrate lobe (segment IV) where it is accessible to the surgeon, whereas the right hepatic duct enters liver tissue almost immediately. In fact this normal arrangement only occurs in 60 per cent of individuals. There are a large number of anatomical variants. The most common (20 per cent) is for one of the main tributaries of the right duct, usually the right anterior duct, to enter the common hepatic duct directly (Fig. 2) 1225. In 12 per cent of individuals there is a triple confluence formed by the right posterior, right anterior, and left hepatic ducts. One important variation is the presence of an anomalous subvesical duct, the duct of Luschka, which runs in the gallbladder fossa. It is found in 12 to 50 per cent of individuals, drains a variable portion of the right liver and is potentially vulnerable during a cholecystectomy.

The main bile duct runs from the confluence of the hepatic ducts to the papilla of Vater (Fig. 3) 1226. It is normally 10 to 12 cm in length and about 6 mm in diameter in anatomical specimens. In life, the upper limit of normal diameter on ultrasound is 7 mm. On direct cholangiography, when the duct is deliberately distended, it is up to 12 mm. The entrance of the cystic duct divides the bile duct into the common hepatic duct above the entrance and the common bile duct below. The supraduodenal portion of the bile duct lies in the free edge of the lesser omentum, anterior to the portal vein and to the right of the hepatic artery. The right hepatic artery normally crosses the common hepatic duct posteriorly, but occasionally it lies in front of the duct. Inferiorly the bile duct curves laterally away from the portal vein and passes behind the first part of the duodenum. It then runs across the posterior part of the head of the pancreas, either in a groove or in a tunnel within the gland. As the bile duct traverses obliquely through the wall of the duodenum it is joined by the main pancreatic duct of Wirsung. The exact arrangement of this junction is variable. Normally both ducts unite to form a common channel of variable length and enter the bowel through the papilla of Vater on the posteromedial wall of the second part of the duodenum. In about 10 per cent of individuals there is no common channel and each duct enters separately. There are very few muscle fibres in the wall of the bile duct, but the proximal bile and pancreatic ducts and the common channel are surrounded by circular and longitudinal smooth muscle. This muscle complex is known as the sphincter of Oddi and the muscle fibres are structurally, embryologically, and functionally distinct from the musculature of the duodenum (Fig. 4) 1227.

The gallbladder is a pear-shaped reservoir 5 to 12 cm in length and situated on the under surface of the liver along the junction between the right and the left liver. It is covered by peritoneum and separated from liver by the connective tissue of the cystic plate. Anatomically, the gallbladder is divided into the fundus, the body, and the neck. The fundus is the widest part of the gland and usually reaches to the free anterior edge of the liver. The neck leads to the cystic duct, and when distended by a stone has the appearance of a diverticulum known as Hartmann's pouch. This pouch occasionally lies very close to the common hepatic duct.

The gallbladder may lie more or less embedded within the liver, or it may be suspended on a mesentery formed from two layers of the peritoneum. The latter variation predisposes to torsion of the gallbladder. Other rare anomalies include agenesis of the gallbladder, in which the ventral pouch off the bile duct fails to form, and duplication or lobulation of the organ where the pouch itself divides to a variable extent.

The cystic duct runs from the neck of the gallbladder to the bile duct and is variable in length. The wall of the cystic duct contains muscle fibres which form the sphincter of Lutkens, while the mucosa is arranged in the spiral valves of Heister. The triangle bounded by the common hepatic duct medially, the cystic duct inferiorly, and the inferior surface of the liver superiorly is known as Calot's triangle. The fact that the cystic artery runs within the triangle makes this an important area of dissection during cholecystectomy. The cystic duct joins the supraduodenal portion of the bile duct either at an acute angle or after running parallel to the bile duct for a short distance. In 5 per cent of people the cystic duct spirals behind the common hepatic duct and enters the bile duct low down within the pancreas. Occasionally the cystic duct actually runs within the wall of the bile duct for a variable distance, and rarely it joins the right hepatic duct. These variations are important since the bile duct can easily be damaged if the precise anatomy is not recognized at operation.

Within the liver the bile ducts are supplied by adjacent arteries. Outside the liver the supply to the bile duct is essentially axial and comes from two arteries that run along either side of the duct, known as the 3 o'clock and 9 o'clock arteries. About 60 per cent of blood flow to the duct arises inferiorly from the retroduodenal and gastroduodenal arteries whilst 38 per cent comes from the hepatic and cystic arteries superiorly (Fig. 5) 1228. The retropancreatic portion of the bile duct is supplied mainly from retroduodenal arteries.

The principal blood supply to the gallbladder is derived from the cystic artery; a smaller component arises from vessels passing directly from the liver. The cystic artery runs above and behind the cystic duct and usually arises from the right hepatic artery after the latter has passed behind the bile duct. Variations in this anatomy are common. The cystic artery may arise from the common hepatic artery and pass in front of the bile duct. There may also be two separate cystic arteries supplying the anterior and posterior surfaces of the gallbladder. There are no discrete veins draining the gallbladder and bile duct, although all the arteries are normally accompanied by a small vein or venous plexus. Some veins drain directly from the gallbladder into the liver. Lymphatic drainage is first to the cystic lymph node which is usually seen adjacent to the cystic artery during a cholecystectomy and thence to the retroduodenal lymph nodes. Some lymphatic channels from the fundus drain to lymphatic channels in the liver capsule. Motor and sensory sympathetic nerves from the coeliac plexus reach the gallbladder along the hepatic artery and the parasympathetic motor supply comes from the right and left vagus nerves.

The prime function of the biliary tract is to convey bile from the liver where it is formed to the duodenum. Along the way bile is stored and concentrated in the gallbladder until it is required. Bile helps in the digestion of certain foodstuffs and acts as a major excretory pathway.

Between 500 ml and 1000 ml of bile are secreted by human hepatocytes every day. The main constituent is water along with bile acids, bile pigments, cholesterol, phospholipids, and all the inorganic ions found in plasma (Table 1) 368. The bile acids are the most important by weight. The precise concentrations of all these molecules are modified subsequently by the epithelium of both the bile ducts and the gallbladder. The pH of bile duct bile is generally above 7, and inorganic ions are normally present in concentrations slightly higher than in plasma with the exception of chloride which is usually lower (Table 2) 369. This is important in clinical practice since patients with a significant bile fistula lose electrolytes rapidly.

The bile acids, cholic and chenodeoxycholic acid, are synthesized in the liver from cholesterol and are the major pathway of cholesterol excretion. In the colon they are metabolized by bacteria to deoxycholic and lithocholic acid, respectively; all except lithocholic acid are absorbed back into the portal circulation and are then re-excreted into the bile (Fig. 6) 1229. This enterohepatic circulation of bile salts takes place several times each day. Because of this continuous circulation there is always a pool of bile acids in the body. A small amount is lost from the pool each day in the stools and is made up by hepatic synthesis.

The main function of the bile acids in bile is to maintain cholesterol in solution, which they do by forming micelles. Hydrophobic cholesterol is encased in hydrophilic phospholipid and bile salts. Only when the concentration of cholesterol exceeds the capacity of the bile salts and phospholipid to maintain it in micellar solution does bile become lithogenic and liable to form stones. Clinically, increasing the concentration of bile salts in bile artificially makes it possible to render bile unsaturated in cholesterol and so enable dissolution of cholesterol gallstones (see Fig. 24 1247 below). Ingestion of food increases bile flow and this is probably mediated by vagal and hormonal stimuli, although bile salts themselves have a powerful choleretic effect.

Bilirubin, the major degradation product of haemoglobin, is conjugated with glucuronide by the hepatocyte and actively secreted into bile. Conjugated bilirubin is converted by the action of bacteria in the bowel into urobilinogen which is reabsorbed into the portal circulation and re-excreted. Some urobilinogen reaches the systemic circulation and is then excreted in the urine where it can be detected. The absence of urobilinogen from the urine implies complete obstruction of bile flow into the bowel.

The gallbladder acts as a store for bile in between meals and concentrates the bile by active reabsorption of water and electrolytes. About half the hepatic output of bile is stored in the gallbladder; the other half trickles into the duodenum continuously. Food, and especially fat, in the duodenum releases cholecystokinin, which is the most important stimulus for gallbladder contraction. Contraction of the gallbladder causes the sphincter of Oddi and the second part of the duodenum to relax. The bile duct acts purely as a conduit, for it does not show peristaltic activity. The sphincter of Oddi certainly plays an important part in bile duct function. The muscle of the sphincter is quite separate from duodenal wall muscle both embryologically and functionally, although the action of the two is usually co-ordinated. This co-ordination occasionally breaks down, but whether this is of clinical significance is not known. The role of the autonomic nerves to the gallbladder and the bile duct is also uncertain.

At endoscopic retrograde cholangiopancreatography (ERCP), distension of the bile duct with contrast causes pain and it is probable that a similar effect occurs in normal life. While a rapid increase in intraductal pressure causes pain, slower increases lead to discomfort. Pain from stones in either the bile duct or the gallbladder probably results from acute obstruction to flow. Spasm of the sphincter of Oddi is probably painless, although it may also lead to a rapid rise in intraductal pressure. Pain nerve endings are widely distributed throughout the biliary tract. Most pain fibres return to the central nervous system via the splanchnic nerves, but a significant minority run with the vagus, right phrenic, and intercostal nerves. This wide distribution probably explains some of the clinical variations in the perception of biliary pain.

Acute and chronic inflammation of the biliary tract are both common. Inflammation can be caused by chemicals, bacteria, or parasites; the aetiology of primary sclerosing cholangitis is unknown. Following obstruction of the gallbladder by a stone in the cystic duct, bile salts leak into the mucosa and cause inflammation. Bacterial infection soon follows. Bacteria are often present in normal bile, particularly if stones are present or if an anastomosis between the biliary tree and the bowel exists. The most common infecting bacteria are Escherichia coli, Klebsiella, and Streptococcus faecalis. Anaerobic bacteria are present in much smaller numbers. Most significant infections are due to multiple organisms. The frequent occurrence of bacteria in bile, even in the absence of acute inflammation, is the reason why prophylaxis with an appropriate antibiotic before any surgical or radiological procedure on the biliary tract is wise.

The Chinese liver fluke, Clonorchis sinensis, Ascaris lumbricoides and, occasionally, a daughter cyst from a ruptured hydatid cyst of the liver are the common parasites which infect the biliary tract, usually in the Middle East and Asia (see Section 41.17 165). Bacterial cholangitis is a common accompaniment, and malignant change in the biliary epithelium may follow chronic infection with Clonorchis sinensis.

Obstruction of the main bile duct leads to morphological changes in the liver with marked inflammatory infiltration of the portal tracts. Scarring and fibrosis around the bile ducts results in the eventual development, after weeks or months of obstruction, of secondary biliary cirrhosis. Hepatocyte function deteriorates progressively from the onset of obstruction and is slow to recover once the obstruction is relieved. Similar pathological changes can be seen in the gallbladder wall when chronic inflammation occurs secondary to gallstones. The gallbladder becomes shrunken, fibrotic, and non-functional (see Fig. 25 1248).

Neoplasia of the glandular biliary epithelium is unusual, and benign tumours are almost unknown. Occasionally adenomatous polyps are seen in the gallbladder or the bile duct.

A plain abdominal radiograph may show radio-opaque gallstones (Fig. 7) 1230 or air in the biliary tree (Fig. 8) 1231. This is a useful investigation in patients who present acutely and is an essential preliminary to any contrast study of the biliary tract. Calcification in the right upper quadrant is not proof of biliary tract disease and neither does the presence of gallstones mean that they are the cause of the patients symptoms.

Two unusual appearances are diagnostic of biliary disease. Gas in the lumen or in the wall of the gallbladder is diagnostic of emphysematous cholecystitis, while the appearance of air in the biliary tree and distal small bowel obstruction suggests gallstone ileus. Another cause of biliary air is a biliary–enteric fistula, either created surgically (Fig. 8) 1231 or as a result of a stone ulcerating from the gallbladder into the bowel, usually the duodenum and very occasionally the colon.

An ultrasound scan is the initial investigation in any patient suspected of biliary tract disease (see Section 6.5 27). It is non-invasive, painless, and can be easily performed on patients who are unwell. Adjacent organs can be examined simultaneously. Ultrasonography may provide unsatisfactory results in patients with obesity, ascites, and gaseous distension, and are dependent on the skill and experience of the operator.

Stones within the gallbladder can be detected with a sensitivity and specificity of over 90 per cent. They appear as reflective foci which cast an acoustic shadow (Fig. 9) 1232 and which move with changes in posture; they may form a layer in the gallbladder. The presence of local tenderness and the thickness of the gallbladder wall allow acute and chronic cholecystitis to be distinguished. A layer of oedema may also appear as a sonolucent zone between the gallbladder and the liver in patients with acute cholecystitis. Polyps within the lumen can be identified but ultrasound cannot, at present, assess gallbladder function accurately.

Ultrasonograpy is always the first imaging technique used in a patient with jaundice or cholangitis. Dilatation of the ducts establishes an extrahepatic obstructive cause for the jaundice and may also identify stones in the ducts (Fig. 10) 1233. An expert can identify the site of the obstruction in three-quarters of patients and the cause in one-third. Ultrasound can also be used during surgery to detect bile duct stones.

Although this was the standard method of investigating the gallbladder for many years, it is now been superseded by ultrasonography. A biliary contrast medium based on triiodobenzoic acid, which is primarily excreted by the liver, is taken by mouth. It is absorbed into the portal venous system, transported across liver cells into bile, and concentrated in the gallbladder, where it becomes visible on a radiograph (Fig. 11) 1234. Patients are then given a fatty meal: a normal gallbladder contracts. The examination is still useful in patients who present with gallbladder symptoms but in whom no abnormalities are detected on ultrasound examination. It is an essential examination when non-operative removal of gallstones is considered, since a functioning gallbladder is a prerequisite for effective treatment. Failure of the gallbladder to opacify is evidence of gallbladder disease, providing the contrast material has been absorbed and the patient is not jaundiced.

A 22-gauge flexible Chiba needle is advanced through the skin and well into the liver under local anaesthesia and antibiotic cover. Blood coagulation must be normal. Contrast medium is gently injected as the needle is slowly withdrawn. The procedure is watched on an image intensifier: when contrast medium enters a bile duct withdrawal is stopped. Contrast medium is then injected to fill the whole biliary tree (Fig. 12) 1235. In skilled hands this can always be achieved if the bile ducts are dilated, and is also possible in about two-thirds of patients in whom the ducts are normal in size. It may be necessary to puncture both the right and the left hepatic systems to outline all the ducts. Bile leakage into the peritoneum, cholangitis, and haemorrhage are the major complications, occuring in about 4 per cent of patients. For this reason it is still best to plan to relieve any obstruction, either surgically or by the percutaneous insertion of a drain or stent, during or fairly soon after the examination. The mortality rate associated with the procedure is about 0.5 per cent.

A full description of this technique is given in Section 27.2 166. The ability to outline the biliary tree and the pancreatic duct as well as to inspect the ampulla of Vater has completely revolutionized the management of many benign biliary problems. Not only has diagnosis been improved (Fig. 13) 1236 but therapeutic techniques have been developed which have improved patient care significantly. Endoscopic retrograde cholangiopancreatography (ERCP) requires technical skill and sophisticated imaging, and is not as widely available as the percutaneous approach. The endoscopic route is preferred initially since it does not transgress the peritoneum, but there are occasions when it is essential to outline the bile ducts from above as well as from below.

Computed tomography (CT) is useful in the diagnosis of biliary tract disease although the evidence is usually indirect. It is easier to identify pathology in the liver, the pancreas, and the gallbladder than the bile duct itself, although the ducts are easily seen when they are dilated (Fig. 14) 1237. CT is probably superior to ultrasonography in identifying the level and the cause of biliary obstruction, but the latter is cheaper, simpler, and safer.

Malignant disease in or around the biliary tree can best be staged by CT; this may also be needed to allow a biopsy to be undertaken. It is not of great value in the management of the common inflammatory conditions, where ultrasound is of greater use. However ultrasound and CT should be regarded as complementary investigations and in difficult cases it is common to use both.

A variety of other imaging techniques may be of value. Intravenous cholangiography, where the bile ducts are outlined directly following intravenous administration of contrast medium, has largely been superseded by ERCP and percutaneous transhepatic cholangiography, which provide better detail.

Isotopic scanning of the gallbladder may be useful in the diagnosis of acute cholecystitis. A technetium-labelled derivative of iminodiacetic acid (HIDA, PIPIDA) is administered intravenously and images are then recorded by a gamma-camera (Fig. 15) 1238. In acute cholecystitis the cystic duct is occluded and so the gallbladder will not opacify; opacification excludes acute cholecystitis. A HIDA scan is particularly useful in the diagnosis of acute acalculous cholecystitis. False positive results may occur in patients with alcoholic liver disease and in those maintained on total parenteral nutrition, in whom the gallbladder is atonic. The isotope may fail to enter the gallbladder despite a patent cystic duct.

Arteriography is essential before any major operation on the biliary system because of the wide variation in biliary arterial anatomy (Fig. 16) 1239. The liver, gallbladder, and pancreas can all be imaged by magnetic resonance (MRI), but the information currently provided is no better than that obtained from CT.

Biochemical measures of liver function abound. In a surgical context interest has focused on bilirubin, alkaline phosphatase, which is excreted by liver cells, and transferase enzymes, which are predominantly located within liver cells. Changes in these three parameters have traditionally been used to differentiate between intra- and extrahepatic causes of jaundice. A rise in alkaline phosphatase signifies an extrahepatic obstruction while changes in enzyme levels indicate disease within the liver cells themselves. These changes are never totally reliable and they have been superseded by ultrasound and the demonstration of dilatation of the bile ducts. They are, however, useful indicators of disease severity, and their main use is to monitor the effects of treatment. Prothrombin time is also a useful measure of liver function, since it depends on the synthetic functions of the liver. Prolongation of the prothrombin time, which might lead to excessive haemorrhage, must be corrected by the administration of Vitamin K or fresh frozen plasma before embarking on any surgical procedure.

Biliary manometry is used to assess the function of the sphincter of Oddi. Pressure traces can be obtained either by placing a special perfusion catheter across the sphincter from below at ERCP or from above during surgical exploration of the common bile duct. The former is used to detect stenosis and dyskinesia of the sphincter of Oddi in patients with persistent pain following a cholecystectomy. Sphincter stenosis is diagnosed by an elevated basal sphincter pressure, and these patients are often cured of their symptoms by an endoscopic sphincterotomy. Other manometric abnormalities have been identified, such as rapid phasic contractions, excessive retrograde contractions, and a paradoxical response to cholecystokinin, but their clinical relevance is not yet clear. Manometry in conjunction with peroperative cholangiography can detect small stones in the bile duct, but the technique is time-consuming and difficult to perform accurately. It is not much used.

Biliary atresia has an incidence of 1 in 12 000 live births and presents in the first week of life as cholestatic jaundice. Untreated it pursues a relentless course, with progressive liver failure and death before the age of 3 years. The cause of the atresia is unknown, but failure of vacuolation of the solid biliary bud in the early weeks of intrauterine life is one possible explanation. Inflammatory obliteration of previously patent ducts occurring about the time of birth is currently considered to be the cause. Viruses and metabolic disorders are two possible causes of such inflammation.

Three pathological types of atresia are recognized: Type 1, atresia of the common bile duct; Type 2, atresia of the common hepatic duct; and Type 3, atresia of the right and left hepatic ducts. Types 1 and 2 are relatively easy to correct surgically. In Type 3 disease there is often a conical area of fibrous tissue at the hilum of the liver which contains within it multiple small biliary radicals. The number of these ducts decreases with time and this adds to the urgency of diagnosis.

Biliary atresia is notoriously difficult to diagnose. Jaundice in the newborn can be caused by hepatocellular disease, intrahepatic bile duct hypoplasia, or a choledochal cyst, as well as biliary atresia. Conventional methods of investigation which are useful in adults are less valuable in infants. For example there is rarely any intrahepatic duct dilatation, so that ultrasound is of limited help. Histological examination of a liver biopsy is the most reliable method of diagnosis, but in clinical practice a range of tests is usually needed.

The discovery on microscopy of small biliary radicals in the fibrous tissue at the hilum of the liver has led to the development of portoenterostomy for the treatment of Type 3 biliary atresia. In this procedure all of the fibrous tissue and atretic ducts at the porta hepatis are resected en bloc. An open enterotomy in the antimesenteric border of a jejunal loop is then sutured to the edge of the fibrous tissue in the porta hepatis. Bile drains from the liver into the bowel through the tiny ducts at the liver hilum. This Kasai operation allows long-term survival of nearly half of the patients (Fig. 17) 1240. If atresia involves only the extrahepatic bile ducts, it is possible to anastomose the residual dilated hepatic ducts to a Roux-en-Y loop of small bowel. Unfortunately the results of hepaticojejunostomy are not much better than those of portoenterostomy. Various modifications of the Kasai procedure have been suggested, including bringing up the Roux loop to the skin surface in order to allow easy access to the hepatic anastomosis, but this appears to convey little advantage.

Bacterial cholangitis and portal hypertension are the two common complications of the Kasai operation. Cholangitis requires treatment with systemic antibiotics and the exclusion of a surgically correctable obstruction such as kinking of the Roux loop. Portal hypertension consequent upon hepatic fibrosis is a long-term problem: injection sclerotherapy is the treatment of choice for children who develop varices.

Even though the Kasai operation has markedly improved the management of biliary atresia the results are not completely satisfactory. However, the results of liver transplantation in children have improved so much that it is now the treatment of choice for children with end-stage liver failure (see Section 10.6 74). Since there are few paediatric liver donors it is necessary to reduce the size of an adult liver for transplantation into an infant, but the surgery and the immunosuppression is tolerated without difficulty. Portoenterostomy remains the first treatment for biliary atresia; liver transplantation is available when portoenterostomy is impossible or liver function fails.

Choledochal cyst is an aneurysmal dilatation of the bile duct. It is a rare condition, with an incidence between 1 : 100 000 and 1 : 150 000 live births in the West, although it is probably more common in the East. Females are affected two to four times more often than are males. Most patients present in infancy, although a significant minority are diagnosed as adults.

The aetiology is unknown. Partial biliary obstruction and a weakness of the wall of the bile duct are the two basic defects required for the formation of a cyst: both these abnormalities may be congenital or acquired. Abnormal recanalization of the bile duct, which is complete by the fifth week of intrauterine development, may result in areas of stenosis and dilatation. This theory is supported by the occurrence of choledochal cysts in neonates and by the finding of multiple areas of stenosis and dilatation in some patients with a choledochal cyst. A cyst may also develop following trauma, or from fibrosis and stenosis of the distal common bile duct due to recurrent cholangitis associated with stones in the bile duct. Early changes of this type are sometimes seen at ERCP.

Cystic dilatation may affect any part of the biliary system: five patterns have been described. Type 1, a cystic or fusiform dilatation of the common bile duct, is the most common (82 per cent). Type 2 (3 per cent) is a supraduodenal diverticulum of the common bile duct, and Type 3 (5 per cent) is a diverticulum of the intraduodenal bile duct, or choledochocoele. Type 4 (9 per cent) consists of multiple cysts: Type 4A cysts affect both the intrahepatic and extrahepatic bile ducts, while Type 4B cysts affect the extrahepatic duct only. Type 5 (1 per cent) describes cysts of the intrahepatic bile ducts. These may be solitary or multiple, and this type includes Caroli's disease (Fig. 18) 1241. They can vary in size from 2 cm in diameter to giant cysts, and the wall is composed of fibrous tissue which may be up to 1 cm thick. The cyst is lined by cuboidal biliary epithelium, which is often ulcerated in adults.

Choledochal cysts present either as a mass or with biliary obstruction. The classic triad of abdominal pain, jaundice, and a mass occurs in less than one-half of patients. Most adults present with jaundice or cholangitis. Infants also present with jaundice, but may vomit due to duodenal compression and may also have a palpable mass in the abdomen.

Ultrasonography will usually confirm the diagnosis. Cholangiography is absolutely essential to delineate the biliary anatomy accurately and thus determine the best approach to surgical treatment. ERCP is the easiest method of obtaining a cholangiogram (Fig. 19) 1242, but percutaneous and operative cholangiography may also be needed. An arteriogram to delineate the relationship of the cyst to the hepatic artery and the portal vein may be very valuable before embarking on surgical treatment.

Once diagnosed the treatment of a choledochal cyst is surgical. Although numerous operations have been described, a Type 1 cyst should ideally be excised completely. The distal bile duct is then anastomosed to the small bowel—usually the jejunum via a Roux-en-Y loop. In infants the structures may be sufficiently mobile to allow use of the duodenum. Anastomoses between the cyst wall and the bowel are usually unsatisfactory in the long term. The cyst wall is often devoid of mucosa and is lined only by granulation tissue, so that a stricture develops. This leads to recurrent cholangitis and the development of stones within the cyst. The high risk of carcinoma developing in a choledochal cyst is also a reason for complete excision. This is usually possible but if it is difficult it is acceptable simply to excise the lining of the cyst and thus protect the portal vein by a partial thickness of the cyst wall. Previous surgery, recurrent cholangitis, and portal hypertension all make treatment difficult.

Type 2 cysts can usually be excised, the defect in the common bile duct being repaired by primary suture over a T-tube brought out through a separate incision in the duct. Small choledochoceles (Type 3) may be treated by endoscopic sphincterotomy. Larger ones require a surgical sphincterotomy using the transduodenal approach. Type 4 cysts are treated by a combination of techniques, depending on the precise anatomy in each individual case. Segmental resection of the liver may be necessary, particularly if there are intrahepatic stones, strictures, or abscesses as well as an extra-hepatic cyst. Hepaticojejunostomy is then necessary to reconstitute biliary drainage.

Rupture may occur spontaneously in infants, and cholangitis develops in both adults and children. Gallstones can develop within the cyst, more commonly in adults (Fig. 19) 1242. Secondary biliary cirrhosis supervenes in 15 per cent of adults with chronic bile duct obstruction. Carcinoma develops within the cyst in 8 per cent of patients and is a fatal complication. The diagnosis is usually made at operation or at autopsy. Most patients are in their thirties, and 75 per cent of tumours are adenocarcinomas, although squamous carcinoma and cholangiocarcinoma also occur. The mean survival after diagnosis is 8.5 months.

The most common acquired abnormality of the biliary system is gallstones. In most patients these remain dormant, but they may cause biliary colic simply by mechanical obstruction. More frequently, stones lead to acute or chronic inflammation within the biliary tree and causes symptoms. Inflammation without stones can occur in both the gallbladder and the bile duct, but is unusual, as are infarction of the gallbladder and benign neoplasms of the biliary tract. Damage to the bile duct occurs rarely at the time of cholecystectomy. It may lead to the development of a benign biliary stricture, which is one of the most serious complications of biliary tract surgery. Abnormalities of biliary function probably do occur but at the present time they are poorly understood.

Gallstones are very common, with a prevalence at autopsy of 11 to 36 per cent. There are at least 5 million people in the United Kingdom and 25 million people in the United States of America with gallstones. Overall the prevalence has probably increased in Western societies over the last 50 years, and it certainly increases with age, from 4 per cent of people in the third decade to 27 per cent in the seventh. This may be related to changes in the biochemistry of bile with age. Women are three times more likely than men to develop stones, and first-degree relatives of patients with gallstones have a two-fold greater prevalence. There are geographical variations. The prevalence is very high in certain American Indian communities (Pima and Chippewa tribes), in Mexico, Sweden, Czechoslovakia, and Chile, and low in Greece, Japan, India, and China. Certain conditions predispose to the development of gallstones. Obesity is a risk factor for gallstones in women under the age of 50. Pregnancy, but not consumption of the oral contraceptive pill, probably predisposes to the development of gallstones (Fig. 20) 1243. Dietary factors which have been implicated include a high energy intake, increased consumption of unrefined carbohydrate, and diets low in fibre. Crohn's disease, terminal ileal resection, and jejunoileal bypass for obesity are associated with a four-fold increase in prevalence. Biliary infection and parasitic infestation of the biliary tree are important factors in the development of pigment stones in Asia but not in the West. Other diseases associated with the development of gallstones include diabetes mellitus, type IV hyperlipoproteinaemia, cirrhosis of the liver, gastric surgery, and total parenteral nutrition. Patients with haemolytic anaemia due to hereditary spherocytosis, sickle-cell disease, and thalassaemia also show an increased prevalence of pigment stones.

Cholesterol and bile pigments are the two principal constituents of gallstones. In addition, calcium carbonate, phosphate, and palmitate are present in variable amounts. Pure cholesterol and pure pigment stones do occur, but most stones are mixed (Fig. 21) 1244. Predominantly cholesterol stones account for 75 per cent of all gallstones in the West. They are single or multiple, hard, and usually layered on cross-section (Fig. 22) 1245. Pigment stones are most common in Asia. They are usually black or brown in colour; brown stones crumble when squashed (Fig. 23) 1246. About 10 per cent of stones contain enough calcium to be radio-opaque (Fig. 7) 1230.

Cholesterol is insoluble in water, and is held in solution as micelles of cholesterol, phospholipids, and bile salts. Lecithin forms the major component of phospholipids while the bile salts are glycine or taurine conjugates. The physicochemical state of bile can be determined from a phase diagram (Fig. 24) 1247. The relative proportions of cholesterol, bile salts, and phospholipid are expressed as a percentage of the total lipid content and are plotted on triangular co-ordinates. An increase in the cholesterol concentration or a decrease in the bile salt concentration results in supersaturation of bile with cholesterol, and the formation of a liquid crystalline phase of cholesterol.

The biliary lipid composition of normal bile and gallstone bile is virtually identical, and since at least half of the Western population have supersaturated bile there must be another factor responsible for the formation of stones. Cholesterol will only crystallize from a supersaturated solution if there is a nidus on which the crystals can form. This process is called nucleation, and the time taken for supersaturated bile to form crystals of cholesterol is known as the nucleation time. Normal bile takes 15 days to form crystals, compared with 3 days for bile from patients with cholesterol gallstones. Mucus glycoproteins from the gallbladder wall and bilirubinate have both been proposed as nucleating factors, while a bile protein has been proposed as an inhibitor. The nucleation phenomenon also depends on gallbladder function: the motility of the wall determines the degree of stasis and mixing of the bile within the lumen. One other significant finding is that the size of the bile acid pool is reduced in many patients with gallstones, although the reason for this is unknown.

Pigment gallstones are formed of calcium bilirubinate and contain less than 25 per cent cholesterol (Fig. 23) 1246. They are usually small and multiple, and about half are radio-opaque. As might be expected they are more prevalent in patients with haemolytic disorders such as hereditary spherocytosis or sickle-cell disease, and in patients with cirrhosis, who commonly have a mild degree of haemolysis. They are frequently found in oriental countries, where they are associated with parasitic infections. Bilirubin in bile is normally conjugated with glucuronide. The enzyme &bgr;-glucuronidase, which may be produced by bacteria such as Escherichia coli, splits the molecule and the unconjugated bilirubin precipitates as the calcium salt. Hydrolytic enzymes from gallbladder mucosa may act in the same way.

Since the sixteenth century it has been realized that most people who have gallstones remain asymptomatic throughout their lives. In a few patients stones are discovered by accident during the investigation of some other problem. In general these stones should be left alone. In a study of patients in whom gallbladder stones were discovered on screening, only 15 per cent developed biliary pain in the subsequent 15 years.

There may be a case for removing asymptomatic stones in diabetics because of their greater susceptibility to infection, and an incidental cholecystectomy for gallstones during a laparotomy for an unrelated condition may sometimes be appropriate because such patients are at greater risk of developing subsequent symptoms. There is no justification for removing the gallbladder with stones to prevent the later development of cancer.

Disease in the gallbladder affects only a small minority of people with gallstones. It presents with a variety of clinical syndromes, of which the most common are chronic cholecystitis, which appears slowly over time, biliary colic, and acute cholecystitis, both of which develop rapidly. Patients occasionally present with the complications of one of these three, either locally in the gallbladder or from stones in the bile duct, and very occasionally from a stone that has ulcerated through into the bowel.

About two-thirds of patients present with chronic cholecystitis. The pathological changes, which often do not correlate well with symptoms, vary from those of an apparently normal gallbladder with minor chronic inflammation in the mucosa to a shrunken organ with gross transmural fibrosis and organized adhesions (Fig. 25) 1248. The mucosa is initially hypertrophied but later becomes atrophied; the epithelium protrudes into the muscle coat, leading to the formation of Rokitansky-Aschoff sinuses. The most severe form is represented by cholecystitis glandularis proliferans in which there are buried areas of hyperproliferative epithelium within the wall of the gallbladder (see Fig. 28 1251 below). Rarely, dystrophic calcification may occur, resulting in the formation of a porcelain gallbladder (Fig. 26) 1249.

The typical patient complains of recurrent attacks of right hypochondrial or epigastric pain, usually after meals, and particularly after consumption of fatty foods. The pain, which often occurs at night, varies from mild indigestion after eating to persistent, moderately severe, right upper quadrant pain which may radiate round to the back and sometimes to the right shoulder or between the shoulder blades. The pain is often described as a tight band all the way round the upper abdomen; very occasionally the pain on the right hand side of the abdomen is suppressed and the patient presents only with left-sided pain.

Nausea usually accompanies the pain, sometimes associated with vomiting. There may be additional minor symptoms such as flatulence and abdominal distension, but these are equally common in patients who do not have gallstones. There may be mild right upper quadrant abdominal tenderness, but examination is usually unremarkable.

It is often possible to make a confident clinical diagnosis of chronic cholecystitis in a patient with classical symptoms, but the presence of gallstones should be confirmed by ultrasonography (Fig. 9) 1232. Occasionally an oral cholecystogram is also needed. When it is difficult to distinguish chronic cholecystitis from peptic ulceration, a hiatus hernia, or diverticular disease, further radiology and endoscopy may be required. The last two conditions often occur together with gallstones, a condition known as Saint's triad.

It is easy to ascribe the patient's symptoms to stones which are found on investigation when this is not the case: many patients with other conditions have gallstones. On the other hand patients with symptoms that show enough features related to proven gallstones are likely to improve on treatment.

Once the diagnosis is established some form of active treatment is indicated since the symptoms will almost always continue. Some patients can control their symptoms by taking care over their diet. Others are only occasionally troubled and simply require mild analgesia. More commonly, some form of surgical treatment is needed to remove the stones, with or without the gallbladder. The risks of surgery must be balanced against the potential benefits, and the views of the informed patient are just as important as the opinion of the doctor. Most surgeons prefer the patient to request the operation.

Biliary colic is due to impaction of a stone in the neck of the gallbladder. The severe pain starts abruptly in the epigastrium, often at night after a heavy meal, and lasts for several hours. It is usually continuous and is associated with restlessness, vomiting, and sweating. The pain may radiate through to the back but does not radiate to the shoulder, as in acute cholecystitis. General examination may disclose a patient in obvious severe pain with a mild tachycardia and normal temperature. Abdominal examination shows only mild tenderness in the epigastrium. In contrast to acute cholecystitis, tenderness over the gallbladder is absent. The gallbladder in patients with biliary colic is often normal in external appearance and shows only mild inflammatory changes on histological examination. Most patients need a strong analgesic given by injection, and after two attacks of severe biliary colic will want some form of definitive treatment.

About one-fifth of patients first present with acute cholecystitis; in about one-third there is clinical or pathological evidence of previous chronic cholecystitis. It is usually due to persistent impaction of a stone in the neck of the gallbladder. The result is initially a chemical inflammation of the gallbladder wall perhaps due to the mucosal toxin lysolecithin, produced by the action of phospholipase on biliary lecithin. This is soon followed by bacterial infection. Because the cystic duct is occluded the inflammatory process is particularly aggressive and the gallbladder becomes acutely distended, with accompanying lymphatic and venous obstruction. The serosa may be covered by a fibrinous exudate and subserosal haemorrhage gives the appearance of patchy gangrene. The gallbladder wall itself is grossly thickened and oedematous and the underlying mucosa may show hyperaemia or patchy necrosis (Fig. 27) 1250. Histologically, three grades of inflammation are recognized: acute cholecystitis, acute suppurative cholecystitis, and acute gangrenous cholecystitis. Rarely an abscess or empyema develops within the gallbladder, while perforation of an ischaemic area leads to a pericholecystic abscess, bile peritonitis, or a cholecystoenteric fistula.

Patients present with acute upper abdominal pain that has often been present for 2 or 3 days. Because the inflammation extends to the parietal peritoneum the pain is well localized and it hurts the patient to move or to breathe. Patients feel generally unwell, may have been febrile, and are anorexic. Physical signs vary with the severity of the inflammation but there is usually some degree of fever and tachycardia. Mild jaundice is present in 10 to 15 per cent of patients. Right hypochondrial tenderness is invariable and there may also be guarding, rigidity, and rebound tenderness. If the latter physical signs are subdued it may be possible to feel the gallbladder itself. Murphy's sign (inspiratory arrest during subcostal palpation) is widely regarded as pathognomonic of cholecystitis. It is certainly present in patients with established acute cholecystitis, but it only reflects peritoneal inflammation in the right upper quadrant, other causes of which include chronic cholecystitis, acute hepatitis, and a localized abscess around a perforated duodenal ulcer. There is usually a clear distinction between acute cholecystitis and biliary colic: this is important since the management is different.

In elderly patients acute cholecystitis may present more insidiously and the frequent absence of typical physical signs results in a delay in diagnosis. In addition, the incidence of complications is higher and the prevalence of intercurrent illness combine to increase the mortality rate 10-fold. Acute cholecystitis is uncommon in children, most of whom have gallstones, sometimes as a complication of haemolytic disease. Acalculous cholecystitis occurs in children with severe sepsis.

Clinically it can be difficult to distinguish acute cholecystitis from acute pancreatitis, acute appendicitis, acute pyelonephritis, perforation of a peptic ulcer, and, occasionally, biliary colic. A raised white cell count and serum amylase level may occur in several of these conditions, although patients with biliary colic rarely have a leucocytosis. Urine should always be examined under the microscope for pus cells and sent for culture if appropriate. One-quarter of patients have disturbed liver function tests, but not all will have stones in the bile duct. There are rarely any specific features of acute cholecystitis on plain radiology, but ultrasound may localize the tenderness to the gallbladder and may demonstrate stones. Free air under the diaphragm on a chest radiograph implies perforation of a viscus, usually a peptic ulcer. A normal HIDA scan excludes acute cholecystitis (Fig. 15) 1238.

Young women who present acutely with severe right upper quadrant pain and signs of peritonitis may have the Curtis– Fitz–Hugh syndrome. Clinically these patients appear to have acute cholecystitis but ultrasound examination fails to show gallstones or any signs of acute cholecystitis. At laparoscopy or laparotomy the gallbladder is normal but there are string-like adhesions between the liver and the peritoneum. This perihepatitis is caused by infection with Chlamydia trachomatis. There may also be evidence of genital tract infection with the same organism. The diagnosis can be confirmed by isolation of the organism from peritoneal fluid or by rising titres of chlamydial antibodies in serum. Treatment is with oxytetracycline 2 g daily for 10 days.

Acute viral hepatitis can sometimes present as acute cholecystitis. The acutely swollen liver is painful and tender but the systemic symptoms and the onset of jaundice soon make the true diagnosis clear.

Acute cholecystitis resolves with conservative treatment in the majority of cases. If admission to hospital is necessary patients require intravenous fluids, analgesia, and suspension of oral intake. Vomiting is unusual, but if present nasogastric aspiration is helpful. If the patient fails to respond intravenous antibiotics are prescribed. Our present choice is cefuroxime 1.5 g three times a day.

Most patients should be offered cholecystectomy, which should normally be undertaken on the next convenient operating list. There is no advantage in letting the acute illness subside and removing the gallbladder 6 weeks later except in a patient who is unfit for surgery and whose condition could be improved by waiting.

An empyema of the gallbladder may be suspected clinically if the physical signs and symptoms fail to improve on conservative management. In particular, fever and right upper quadrant tenderness fail to abate, and there is a persistent or increasing leucocytosis. With time the gallbladder becomes necrotic and ruptures, resulting either in a localized abscess or in generalized peritonitis. An empyema is really an abscess within the gallbladder and it must therefore be drained. The best method is to insert a pigtail catheter into the gallbladder under ultrasound control, as the gallbladder is usually adherent to the peritoneum of the abdominal wall. If there is any doubt a transhepatic route for the catheter should be chosen. Percutaneous drainage is clearly less disturbing for the patient, who is usually quite ill and toxic. If it fails for any reason a conventional surgical approach must be adopted. Occasionally a safe cholecystectomy can be performed by an experienced surgeon. For everyone else a cholecystostomy is better.

This is a severe and fulminant form of acute cholecystitis which accounts for less than 1 per cent of cases. Stones are absent in 30 to 50 per cent of patients, who are usually elderly men, and 40 per cent have diabetes mellitus. It is caused by a mixture of bacteria which includes gas-forming organisms, and the pathognomonic diagnostic sign is gas within the wall or the lumen of the gallbladder seen on a plain radiograph. The onset of the disease is abrupt and the condition of the patient deteriorates rapidly. There is a high incidence of gangrene and perforation, and emergency cholecystectomy is needed.

This is a rare but severe form of chronic cholecystitis in which the gallbladder is thickened and irregular with extensions of yellow xanthogranulomatous inflammation to adjacent organs. Foamy macrophages and giant cells are seen within connective tissue in the wall of the gallbladder. The condition is thought to be due to bile penetrating deeply into the gallbladder wall. The appearances both on investigation and at operation resemble carcinoma of the gallbladder; frozen section histology at operation may be necessary because the two conditions are associated.

Acute cholecystitis can develop in the absence of gallbladder stones. It is most often seen in the intensive care unit and is associated with severe illness such as multiple trauma, extensive burns, major surgery, and sepsis, often in an elderly person. The aetiology is unknown, but is thought to be related to gallbladder distension and bile stasis. The normal contraction of the gallbladder is inhibited in patients with sepsis and those on total parenteral nutrition, especially if opiate analgesics are administered. This allows the development of biliary sludge, which may be demonstrated in the gallbladder of many patients with major illness, not all of whom develop acalculous cholecystitis.

Pathological examination of the gallbladder reveals oedema of the serosa and muscular layers, with patchy thrombosis of arterioles and venules. Areas of necrosis develop and may affect the underlying mucosa. One possibility is that activation of factor VII by trauma may lead to thrombosis of blood vessels in the seromuscular layer of the gallbladder.

In a severely ill patient, the development of acute acalculous cholecystitis is usually insidious. The clinical features are similar to those of acute calculous cholecystitis but they are often masked by the underlying condition. Ultrasound is the most useful investigation, and may show biliary sludge in a tender thickened gallbladder, but fails to demonstrate stones. All the indicators of liver function deteriorate, and a HIDA scan will fail to demonstrate the gallbladder.

Once the diagnosis is made an immediate cholecystectomy is necessary because of the high incidence of gangrene of the gallbladder. The mortality rate varies with the nature of the underlying condition but is generally higher than that in patients with acute calculous cholecystitis.

This is caused by the deposition of cholesterol in the mucosa and submucosa of the gallbladder wall and produces the classical ‘strawberry gallbladder’. Microscopy shows macrophages loaded with cholesterol. Ultrasound identifies the cholesterol in the wall as bright shiny spots, and there may also be cholesterol stones within the lumen. Cholesterolosis may cause pancreatitis, perhaps as a result of small cholesterol crystals passing down the bile duct and briefly occluding the ampulla, so that symptomatic patients should be advised to undergo cholecystectomy.

Adenomyomatosis or cholecystitis glandularis proliferans is characterized by hypertrophic smooth muscle bundles and epithelial sinus formation. The gallbladder has a thickened wall which may be divided into two separate sections by a stricture of incomplete septum (Fig. 28) 1251. Granulomatous polyps develop in the lumen at the fundus. Inflammation develops later and gallstones are sometimes present. Symptomatic patients require a cholecystectomy. Others in whom the diagnosis is made but not treated require surveillance since adenomyomatosis may predispose to carcinoma.

A mucocele of the gallbladder forms when a stone impacts in the cystic duct but bacterial infection does not occur. Bile is reabsorbed but the epithelium continues to secrete mucous, and the gallbladder becomes distended (Figs. 29, 30) 1252,1253. It is easily palpable and may even be visible, but it is not tender. Such patients have somewhat subdued but nevertheless persistent symptoms, often including distressing nausea. If infection does occur an empyema may develop rapidly. In either circumstance a cholecystectomy is required. Rarely a mucocele of the gallbladder may perforate. Although pseudomyxoma peritonei has been reported to follow rupture of a mucocele it probably only follows rupture of a cystadenoma or cystadenocarcinoma of the gallbladder.

Infarction of the gallbladder due to torsion or volvulus is a rare event. Two anatomical anomalies permit torsion. Firstly the gallbladder may have no attachment to the liver, lying free in the peritoneal cavity suspended only by the cystic duct and artery. Secondly, and more commonly, the gallbladder is suspended from the liver by a narrow mesentery. Acute torsion causes right-sided abdominal pain and the tense, infarcted gallbladder may be palpable (Fig. 31) 1254. It is often misdiagnosed as acute appendicitis. Intermittent torsion can occur and produces periodic bouts of pain.

A small group of patients, usually young women, presents with pain in the right hypochondrium which, in the opinion of everyone who sees them, is typical biliary pain. However, all conventional biliary investigations, which may be repeated on several occasions, are normal. Furthermore a minority benefit from cholecystectomy even though no pathological abnormality is discovered in the gallbladder at operation.

Now that cholesterolosis and adenomyomatosis can be excluded by ultrasound studies before operation interest has centred on the possibility that these patients have a functional disorder of the biliary tract. This idea has received support from the discovery that some develop identical pain following an intravenous injection of cholecystokinin, and it was hoped that this would identify those who would benefit from a cholecystectomy. This test has not turned out to be so specific, but there are a number of other experimental tests of gallbladder and biliary function which may help us to understand these patients better in the future.

In practical terms, it is essential to exclude the irritable bowel syndrome which can produce symptoms very similar to those of biliary pain. After explaining the position very carefully to the patient it is reasonable to proceed to a cholecystectomy. Unfortunately the pain persists after operation in some patients; these form part of a group of patients with postcholecystectomy pain.

The first successful cholecystectomy was performed by Langenbuch in 1882, and since then the operation has become the standard treatment for gallbladder stones. It is both safe and effective by modern surgical standards. However, there are deaths and complications following the operation and it takes 6 to 8 weeks to recover following a conventional open operation. An alternative to surgery would clearly be useful. Our understanding of the biochemistry of gallstone formation first led to the development of drugs which dissolve cholesterol gallstones. Further developments have produced a bewildering array of methods for removing or dissolving stones without the disadvantages of surgery.

Cholesterol gallstones can be dissolved by decreasing the cholesterol saturation of bile. The naturally occurring bile salt chenodeoxycholic acid and the synthetic ursodeoxycholic acid when given by mouth achieve this. They probably have their effect by reducing the hepatic synthesis of cholesterol rather than by expanding the bile acid pool. Ursodeoxycholic acid is more efficient at reducing the cholesterol saturation of bile, but both drugs are equally good at dissolving gallstones in vivo. Because they work in slightly different ways there are advantages to giving them together. They are known to be safe, although chenodeoxycholic acid, which is by far the cheaper drug, causes diarrhoea and abnormalities of liver function tests in some patients. One interesting but unexplained benefit is that some patients experience relief of their symptoms whilst taking the drugs even though there is no effect on the size of their stones.

Dissolution therapy can only be used for non-calcified stones within a functioning gallbladder; as a consequence, less than 20 per cent of patients presenting to a doctor are suitable candidates. These drugs are obviously unsuitable for patients with acute symptoms and are less effective in obese patients and those with stones more than 15 mm in diameter.

The protocol for gallstone dissolution therapy is onerous. Prior to starting treatment the size of stones is measured. Either chenodeoxycholic acid (10–15 mg/kg.day) or ursodeoxycholic acid (8–12 mg/kg.day and up to 15 mg/kg.day in obese patients) is started. Liver function is carefully monitored and the stones are measured at 6 months. If there has been no reduction in size there is no point in continuing with treatment. Eighty per cent of small stones dissolve in 6 months, but larger stones require up to 2 years treatment. Even then only 14 per cent of patients were free of stones in the largest reported study.

Compliance may be a problem over such a long time, and female patients need to take adequate precautions against pregnancy. Better results are obtained in thin rather than obese patients, in women rather than men and in those patients with small lucent gallstones that ‘float’ as a layer on oral cholecystography (Fig. 11) 1234. Stones that are initially radiolucent occasionally calcify, in which case dissolution therapy is no longer effective. Gallstones recur within 5 years of treatment in 50 per cent of patients.

Overall, dissolution therapy provides a viable alternative to surgery in a small proportion of carefully selected patients. This mode of treatment may be particularly useful in patients who are poor anaesthetic risks or who refuse surgery.

All of these techniques depend on the percutaneous puncture of the gallbladder and the removal of stones either mechanically or by dissolution. Some procedures can be performed under local anaesthesia, others require general anaesthesia, but none requires a conventional surgical incision. Mechanical removal of the stones, with or without crushing, can be achieved under direct vision after dilating the percutaneous track to the gallbladder, in a similar fashion to percutaneous nephrolithotomy. After removing all the stones attempts have been made to obliterate the gallbladder lumen by instilling drugs such as tetracycline.

Many chemicals have been tested for their ability to dissolve gallstones and a few of them are clinically useful. Methyl tert-butyl ether is an alkyl ether that rapidly dissolves cholesterol. It smells unpleasant and causes vomiting and sedation if it is absorbed; the catheter should take a transhepatic route to the gallbladder to minimize the possibility of intraperitoneal leakage. Small volumes of methyl tert-butyl ether, which will not overflow into the bile duct, are then instilled and aspirated cyclically until the stones have dissolved.

The stone recurrence rate following either procedure has not yet been assessed but there is no reason to think that it will be any different to the results following dissolution with oral therapy.

Extracorporeal shock wave lithotripsy was first introduced for the management of renal calculi and has subsequently been adapted for fragmentation of both gallbladder and common bile duct stones. Once again the stones should be radiolucent and the gallbladder must function so that the tiny fragments of stone can pass spontaneously. Adjuvant oral dissolution therapy is required concurrently. The stones should be less than 30 mm in diameter and there should not be more than three (ideally only one). These criteria restrict the use of extracorporeal shock wave lithotripsy to between 5 per cent and 10 per cent of patients.

Shock waves are generated either by a spark gap system, a piezoelectric generator, or by the electromagnetic deflection of a metal membrane. They are then synchronized with the r wave of the electrocardiogram and focused on to the gallstone, which is imaged using either ultrasound or X-rays. With modern piezoelectric machines the treatment is virtually painless, even though more than one treatment and several thousand shocks may be required. Cutaneous petechiae, transient haematuria, and mild pancreatitis are recognized complications, and about one-third of patients experience biliary colic. Oral treatment with stone-dissolving drugs needs to continue, but in one reported series by the end of 2 years after extracorporeal shock wave lithotripsy the gallbladder was empty in all the patients who had solitary stones and in three-quarters of those with multiple stones.

Any fragments of stone which remain can act as a nidus for recurrent stones, but at the moment the recurrence rate after complete clearance of the gallbladder is not known.

Cholecystectomy is the most common major abdominal operation in the Western world, and the rules for its safe execution are well established even though there are a number of different techniques. Elective operations, planned for the convenience of the patient and the surgeon, play an important role in training because a cholecystectomy teaches several important surgical principles. A routine operation requires careful dissection within a confined space in an important anatomical area and no major structure should be divided until the anatomy has been clearly identified. A certain degree of surgical skill is needed and successfully completing the operation is always a landmark in a young surgeon's career.

Patients who are admitted as emergencies may require an immediate operation by an experienced surgeon. More commonly they will respond to conservative treatment and should undergo operation on the next convenient list. There are no surgical advantages in waiting for 6 weeks while the inflammation subsides although there may, on occasion, be medical advantages. With the advent of ultrasound it is now easy to make the diagnosis acutely. A delayed operation is no easier and several trials have shown that the early operation is not associated with a greater risk of damage to the bile duct. Furthermore conservative treatment fails for one in seven patients, and a similar number are readmitted with a further acute attack before their planned admission date. From the economic point of view operation during the first admission saves money.

Fluid depletion and electrolyte imbalance should be corrected in the acutely ill patient, and blood should be grouped and serum saved for crossmatching should blood transfusion be needed.

Routine preoperative antibiotic prophylaxis to prevent wound infection is always appropriate. Although the incidence of anaerobic bacteria in the biliary tract is low our present practice is to give everyone metronidazole 0.5 g and cefuroxime 1.5 g intravenously on induction of anaesthesia. This is probably sufficient, but some surgeons also give a second dose 12 h after operation.

Routine prophylaxis against deep venous thrombosis is also necessary. Patients undergoing elective operations should stop the contraceptive pill 1 month in advance and everyone should wear compression stockings on their legs. Patients as well as staff should appreciate the importance of mobility after the operation. Several drugs reduce the incidence of deep vein thrombosis, and some also reduce the incidence of pulmonary embolism. Our choice is to give 500 ml Dextran 70 during surgery and a further 500 ml during the first 24 h postoperatively. High-risk patients receive 6000 units heparin by subcutaneous injection 2 h before operation and every 12 h thereafter.

The principles of the operation are the same whichever surgical approach is used. They are to isolate, occlude, and divide the cystic artery and the cystic duct, and then to remove the gallbladder from the liver bed. A peroperative cholangiogram helps to delineate the biliary anatomy and to identify stones in the bile duct: the operation is best performed on an operating table suitably adapted for cholangiography. General anaesthesia with good relaxation provides the best exposure.

Four incisions can be used for cholecystectomy: midline, right paramedian, right subcostal, or right transverse. A midline incision is useful when the diagnosis is not definite, while a subcostal incision gives the best exposure when difficulties are expected. However, it does not provide good access to the rest of the abdomen. A transverse incision gives a good cosmetic result and less postoperative pain but provides more limited exposure. Choosing the most appropriate incision for any particular patient depends partly on the preference of the surgeon, partly on the build of the patient, and partly on the expected pathology. Improvements in preoperative diagnosis have reduced the need for a full diagnostic laparotomy. On the other hand it is easy and essential always to examine the gallbladder, the liver, the pancreas, the stomach, and the duodenum. In most operations it will be possible to assess the diameter of the bile duct.

The operative field should be exposed by retraction of the liver upwards, with traction anteriorly and to the right on the neck of the gallbladder with a suitable forceps, while a damp pack held by the assistant retracts the colon and the duodenum inferiorly. Occasionally it is helpful to bring the whole liver down into the wound with a pack placed over the dome of the liver. If the gallbladder is tense and difficult to grasp the operation may be made easier by aspiration of the contents.

The peritoneum over the neck of the gallbladder is incised in front and behind and the contents of Calot's triangle displayed by a combination of blunt and sharp dissection (Fig. 32) 1255. Normally, the cystic duct lies in the inferior margin of the triangle with the common hepatic duct medially. The cystic artery crosses the triangle from left to right, running behind the bile duct and arising from the right hepatic artery, which may be visible. However the anatomy is very variable and the dissection must proceed until there is no doubt as to the identity of all the vascular and ductal structures which have been exposed. Once the cystic duct and artery have been definitely identified, the cystic artery is ligated in continuity and divided between ligatures. The cystic duct is dissected as far as is necessary to expose a sufficient length for easy cannulation for operative cholangiography. Any stones in the cystic duct are milked back into the gallbladder and the cystic duct is ligated close to the gallbladder. If cholangiography is to be performed it should be done at this stage. When satisfactory pictures have been obtained the cannula is removed and the cystic duct ligated or oversewn with an absorbable suture. The dissection of the gallbladder from the liver can begin either at the fundus or in the region of the cystic duct. Either way it is important to keep close to the gallbladder wall, and diathermy is needed to achieve haemostasis. Drainage after cholecystectomy is controversial, but we prefer to leave a vacuum drain in the gallbladder bed for 24 h after operation.

Sudden arterial haemorrhage during a cholecystectomy usually arises from a torn cystic artery. The bleeding point should not be clipped; instead, the wound should be packed tightly with a small swab. It is then essential to wait while haemostasis develops. During this time the surgeon can ensure that the exposure and the illumination are optimal. The wound is then kept dry with a strong sucker while the bleeding point is sutured with a fine 4/0 or 5/0 Prolene stitch. Very occasionally the only way of controlling haemorrhage while the damage is repaired is by occluding the hepatic artery with the fingers and thumb of the left hand placed across the entrance of the lesser sac (Pringle's manoeuvre).

It is sometimes quite impossible to delineate the anatomy of the ductal system by dissection. In these circumstances a cholangiogram is absolutely vital. It is also invaluable when the anatomy is unclear and there is a leak of bile from an unidentified duct.

There are good arguments for performing operative cholangiography routinely. From a practical viewpoint good cholangiograms are only obtained with regular practice but they also demonstrate the precise anatomy of the biliary tree (Fig. 33) 1256. On the other hand only a small proportion of cholangiograms disclose stones in the duct, some false positive results are obtained, and stones are actually removed from only two-thirds of ducts explored as a result of an abnormal peroperative cholangiogram. It is preferable, therefore, to select patients for operative cholangiography on the basis of a history of jaundice, abnormal preoperative liver function tests, small stones in the gallbladder, and dilatation of the bile duct on preoperative ultrasonography and at operation. A suitable cannula is tied into the cystic duct or a fine butterfly needle is introduced directly into the bile duct itself. After the careful elimination of any air bubbles from the syringe and cannula, dilute contrast material (25 per cent sodium diatrizoate) is then injected. Ideally this should be done during screening of the patient, but more commonly two radiographs are taken, the first after injection of 3 to 5 ml and the second after a further 8 to 12 ml of contrast has been injected. On the first film the bile duct itself will be seen; the second film shows the intrahepatic biliary radicles and contrast in the duodenum. Filling defects in the contrast or the absence of flow into the duodenum are evidence of stones within the duct.

Some surgeons feel that dissection of Calot's triangle first takes the surgeon too close to structures that should be avoided. They prefer to start the operation at the fundus and remove the gallbladder from the liver first. By keeping adjacent to the gallbladder wall the cystic artery and cystic duct are eventually exposed and can be tied well away from other important structures, which are often never seen. Operative cholangiography is performed towards the end of the operation if necessary. Bleeding from the gallbladder bed can be a nuisance and obscure the view of Calot's triangle, but this approach may be easier in a patient with an acutely inflamed gallbladder. It should certainly be adopted if the initial dissection of Calot's triangle in the conventional operation proves to be difficult.

Much of the morbidity associated with a conventional cholecystectomy arises from the abdominal wall wound which is needed to provide sufficient exposure. However, with modern imaging there is little need for either a laparotomy or an operative cholangiogram, which are the main reasons for a large wound. Minicholecystectomy is performed via a subcostal incision no more than 10 cm long placed right over the gallbladder, which is then dissected out fundus first. Metal clips are placed to occlude the cystic duct and the cystic artery. The incision is closed without drainage. There is little postoperative pain or systemic upset and patients can be discharged 2 or 3 days after surgery.

This is an extension of minicholecystectomy but it introduces a completely new concept into abdominal surgery. Laparoscopic cholecystectomy is rapidly replacing open cholecystectomy as the procedure of choice in developed countries.

The operation is performed through four laparoscopic ports inserted through the abdominal wall in the right upper quadrant (Fig. 34) 1257. The dissection is viewed on a television screen placed beside the operating table and the image is obtained from a television camera attached to a telescope inserted through the subumbilical port.

The cystic duct and the cystic artery are dissected out in exactly the same way as a conventional cholecystectomy, except that subtle alterations in manual dexterity and specialized instruments are required (Fig. 35) 1258. Clips are used to occlude the cystic duct and the cystic artery. It is perfectly possible to cannulate the cystic duct for cholangiography (Fig. 36) 1259. The gallbladder is dissected from the liver bed using diathermy or sharp dissection: this is often the most difficult part of the operation. The gallbladder is extracted from the abdominal cavity through the umbilical or epigastric incision which may need to be enlarged. A drain can be left to the gallbladder bed if desired. The procedure takes slightly longer than conventional cholecystectomy but postoperative recovery is faster. Pain and sepsis in the wounds are less of a problem (Fig. 37) 1260. It remains to be seen whether the mortality and morbidity associated with this procedure are better than those after conventional cholecystectomy.

Most patients recover rapidly, irrespective of the method used for removing the gallbladder. Very few want anything to drink until the following day, except after a laparoscopic procedure when some patients will be able to eat and drink almost as soon as they return to the ward. Unless there is bile in the drain it can usually be removed after 24 h. Prolonged ileus is uncommon and most patients eat on the second postoperative day. After a conventional operation patients need to stay in hospital for 4 or 5 days, compared to 2 or 3 days after a laparoscopic or minicholecystectomy. Most patients need 6 to 8 weeks away from work after a conventional operation, whereas after a laparoscopic procedure 2 weeks is usually sufficient.

Surgical drainage of the gallbladder is rarely necessary: percutaneous ultrasound-guided drainage can now achieve the same result with less disturbance to the patient. On the other hand the surgeon may embark on an urgent cholecystectomy only to realize that the pathology is too severe to allow a safe operation. In these circumstances it is much better simply to drain the gallbladder with a large tube after removing all the stones, allow the inflammation to settle and to remove the gallbladder 6 weeks later.

In the same circumstances an alternative to cholecystostomy is partial cholecystectomy. The gallbladder is evacuated of bile and stones and, starting at the fundus, it is dissected away from the liver as far as possible towards the neck of the gallbladder. Part of the wall of the gallbladder may be left in the gallbladder fossa if dissection of the gallbladder away from the liver bed proves difficult. Once the dissection has proceeded as close to the cystic duct and Calot's triangle as is safe, the remainder of the gallbladder is excised and its neck is oversewn. Operative cholangiography is not usually possible, but it is important to try and be sure that any stones in the cystic duct are removed and to leave a drain to the gallbladder bed.

Conventional cholecystectomy is a safe operation: although complications arise in about one to 10 patients they are rarely serious. Pulmonary complications are the most common; wound infection, deep vein thrombosis, and cardiovascular problems account for the remainder. Overall about 1 per cent of patients die. However, there is considerable variation in mortality rate with age. Cardiac and respiratory problems are more frequent in the elderly and it is more common to find complications from the stones themselves, such as an empyema or cholangitis: the mortality rate in patients over the age of 70 may reach 10 per cent.

Damage to the bile duct is a complication that everyone rightly fears (Fig. 38) 1261, and occurs roughly once in every 500 cholecystectomies. Damage is avoided by following every rule of the operation without fail on every occasion. If the duct is damaged it is important to recognize the injury and to repair it immediately. The results are then good. When the damage is only recognized some days after the operation, the patient is septic and a biliary fistula has developed.

Persistent or recurrent symptoms, excluding early operative complications, are common after cholecystectomy and may be due to a number of conditions. In one prospective study 50 per cent of patients had symptoms 1 year after a cholecystectomy. Fortunately the majority of patients have only mild complaints and often do not seek medical advice. Severe symptoms occur in 5 to 10 per cent of patients. They are more common in middle-aged patients with a long preoperative history and those who had a normal gallbladder removed. Upper abdominal pain and dyspepsia are common and may be acute and severe. Two-thirds of these patients experience symptoms similar or identical to those experienced before surgery.

When a patient presents with recurrent symptoms the first cause to exclude is a retained or recurrent stone in the bile duct. This accounts for about one-third of the patients. In a further one-third another cause, such as pancreatic or liver disease, peptic ulceration, or the irritable bowel syndrome, is found, and the original diagnosis of gallbladder disease was probably wrong.

Some patients, particularly those in whom the gallbladder was normal, have often had other intra-abdominal organs such as the appendix or the uterus removed. They may show symptoms of anxiety or depression, and they tend to focus a lot of attention on relatively mild symptoms. It is important to exclude the presence of objective organic disease in the biliary tract as far as possible, and then to offer these patients treatment for the underlying problem. Further surgery, including endoscopic sphincterotomy, should be avoided. Even after all the appropriate investigations have been done, no satisfactory cause for the symptoms is found in about one-quarter of such patients.

Stones in the bile duct may lie dormant for many years and only come to light because of an episode of pain, jaundice, or cholangitis (Fig. 13) 1236. They may also be discovered by ultrasonography during investigation for stones in the gallbladder (Fig. 10) 1233 or by cholangiography during cholecystectomy (Fig. 33) 1256. Between 8 and 15 per cent of patients with stones in the gallbladder also have stones in the ducts (choledocholithiasis). The incidence increases with age: one-quarter of patients over 60 years of age have stones in both sites. In patients from the West, most stones are found in the common bile duct, whereas in the East hepatic duct stones are more usual.

Primary stones form within the bile duct. They are usually bilirubinate stones of the soft brown type, and they are associated with biliary stasis due to obstruction, infection, and the presence of foreign bodies such as food. In the Orient they are generally caused by infection, sometimes associated with parasites within the biliary tract. However, most common duct stones originate in the gallbladder and migrate through the cystic duct into the common bile duct. These secondary stones consist mostly of cholesterol and often grow in size within the duct.

Although stones in the bile duct may be silent, the development of symptoms is potentially serious; obstructive jaundice, ascending cholangitis, and acute pancreatitis are all associated with major morbidity and mortality.

Less seriously, stones in the ducts may cause bouts of abdominal pain or dyspepsia indistinguishable from symptoms of gallbladder disease or of intermittent biliary colic with transient jaundice. Elderly patients with bile duct stones sometimes present in apparently obscure ways with malaise, confusion, collapse, or septicaemia (Fig. 39) 1262. The cause is often only discovered when routine liver function tests are found to be abnormal. Until recently stones in the bile duct were most commonly discovered at operation. About one in every 10 patients undergoing cholecystectomy was discovered to have stones in the bile duct and required exploration of the duct, although stones were only recovered in perhaps two-thirds of the explorations. Nowadays most bile duct stones are diagnosed by ultrasound and removed endoscopically before cholecystectomy, although surgical exploration of the bile duct is still occasionally necessary.

Occasionally, a small stone passes into the bile duct and impacts at the ampulla, causing pain and jaundice. The severity of the jaundice depends on the duration of the obstruction, but as the stone passes on spontaneously the jaundice resolves. A solitary stone may disappear from the biliary tree in this way, but normally some stones remain in a thick walled gallbladder to support the diagnosis. Such patients need a cholecystectomy, and an operative cholangiogram is essential.

More commonly there is a larger stone or stones within a dilated bile duct. Sometimes a large number of stones in the duct leads to a significant impairment of bile flow. At other times a stone moves up and down within the duct and acts as a ball valve, causing pain and jaundice when it impacts but allowing the symptoms to resolve spontaneously when it moves away. The site of impaction is usually immediately above the ampulla, but it may be above a fibrotic narrowing in the bile duct caused by the stones themselves. Complete impaction of a stone causes severe progressive jaundice.

Stones in the bile duct usually cause pain. However, it is not easy to distinguish obstructive jaundice due to stones from that due to malignant disease on the basis of pain. Clinical examination normally discloses nothing except a jaundiced patient, and possibly some scratch marks from the intolerable itching. The gallbladder is not palpable since it is thick-walled and fibrotic, and it resists distension, although there is often mild tenderness in the right upper quadrant.

Many of these patients are elderly and require prompt endoscopic sphincterotomy and extraction of their stones. Cholecystectomy can be performed later when the jaundice has resolved. In practice only 10 per cent of such patients have continuing symptoms and need surgery. Patients under the age of 50 who are not profoundly jaundiced are best treated by cholecystectomy and exploration of the duct.

Ascending cholangitis is still a fatal disease and it must be treated as a medical emergency. Fortunately it is usually an easy diagnosis to make clinically, as most patients present with the classic symptoms of epigastric pain, rigors, and jaundice (Charcot's triad or Charcot's intermittent biliary fever). Elderly patients sometimes present simply with septicaemia or collapse with little or no jaundice, and rarely the origin of a Gram-negative septicaemia is eventually traced back to the bile duct.

Cholangitis is always associated with some degree of obstruction within the bile duct: stones in the ducts are the cause in 80 per cent of cases. Many of the patients are elderly. Cholangitis is a rare presentation of malignant biliary obstruction, except in those with carcinoma of the ampulla. Patients with a benign biliary stricture commonly experience recurrent episodes of cholangitis and they always have bacteria in their bile, as do patients with an endoluminal prosthesis in place. Patients with stones nearly always have a positive bile culture, whereas this is only found in 10 per cent of patients with malignant jaundice.

Most of the bacteria cultured from the bile in patients with cholangitis are also found in the bowel. Escherichia coli, Streptococcus faecalis, and Klebsiella species are the most common pathogens, but Staphylococcus, Pseudomonas, and Proteus may occasionally be present. Anaerobic bacteria such as Clostridium perfringens and Bacteroides fragilis, although rarely cultured from gallbladder bile, are an important feature in cholangitis. Bacteria reach the liver in the portal vein and are normally cleared there by the reticuloendothelial system. There is also evidence of cholangiovenous reflux of organisms into the circulation when the systemic symptoms of cholangitis become apparent. More than one organism is present in over half of all patients, and there is some evidence of synergy between the aerobic and anaerobic organisms. Antibiotic treatment, which should always be vigorous, must take account of the polymicrobial nature of most infections.

The obstructed bile duct must be drained adequately, by the most effective route, and as quickly as possible. However, the patient must first be resuscitated with intravenous fluids and antibiotics. Antibiotic treatment of septicaemia will produce improvement in the patient for a short period, but it will not cure the patient unless the obstruction is relieved. Nowadays this can usually be achieved by an endoscopic sphincterotomy (Fig. 40) 1263, but occasionally conventional surgical drainage is still necessary.

Progression of the septic process within the bile ducts can occur in two separate ways. Sometimes pus develops within the ducts; intrahepatic abscesses may also appear. These abscesses may rupture through the hepatic capsule and give rise to intraperitoneal collections. Purulent cholangitis is often associated with a degree of tension within the biliary system, and there is a gush of purulent bile into the duodenum when the offending stone is released endoscopically.

Alternatively the sepsis may become systemic. Progressive renal and cardiac impairment ensues, and patients develop septic shock. Dialysis or haemofiltration may be required. Occasionally, the presenting feature of cholangitis is complete renal failure or cardiovascular collapse; the mortality rate in these patients is very high.

Acute pancreatitis is associated with gallstones (see Section 25.1 170). Impaction of a small stone at the ampulla and occlusion of the pancreatic duct is a cause of pancreatitis in a minority of patients. An early ultrasound examination of the biliary tract is therefore essential in every patient who is admitted with acute pancreatitis, particularly if there is any change in the liver function tests. A few have evidence of stones in the bile duct and an immediate endoscopic sphincterotomy and extraction of the stone is well worthwhile in these patients, as it may abort the episode of pancreatitis immediately. There is no evidence that the pancreatitis is made worse by ERCP, although it is wise to avoid cannulating the pancreatic duct.

This is an unusual and specific cause of obstruction of the common hepatic duct by a stone impacted in the cystic duct or Hartmann's pouch. The stone may simply press on the bile duct, but more commonly it ulcerates into the duct, creating a cholecysto-choledochal fistula. Patients present with obstructive jaundice, and cholangiography shows narrowing of the bile duct at the porta hepatis, which can have the appearance of a cholangiocarcinoma ( Fig. 41 1264, Fig. 42 1265). The true pathology is eventually identified at surgery, but the operation is often extremely difficult because of severe inflammation and fibrosis. It is best to excise the gallbladder, and it is essential to remove the stone causing the obstruction. If this leaves a large gap in the wall of the bile duct, a biliary enteric bypass is needed. Reconstruction of the bile duct over a t-tube brought out through a separate stab incision is possible for smaller defects.

The most important investigation is ultrasound examination of the liver, the bile duct, the gallbladder, and the pancreas. It should be undertaken on the least suspicion of stones or another obstructive lesion in the bile duct. The ultrasonographer need only decide whether or not the bile ducts are dilated. The normal common bile duct should not be greater than 7 mm in diameter when measured on ultrasound (Fig. 10) 1233. If the ducts are dilated, the patient has an extrahepatic obstructive cause for his or her symptoms. If the ducts are not dilated it is unlikely that there are stones in the bile duct, but there are two important exceptions to this rule. If the examination is done very soon after a stone has entered the bile duct there may have been insufficient time for dilatation to have developed. The examination should be repeated 1 week later. In patients with cirrhosis of the liver the intrahepatic bile ducts are simply not able to dilate. If there is clinical uncertainty about the presence of a stone within the ducts a cholangiogram is needed.

An experienced ultrasonographer can always detect dilation of the ducts, but the site of the obstruction will only be identified in two-thirds of patients, and the cause of the obstruction in one-third. Nevertheless stones and strictures can sometimes be identified on ultrasound.

Before the introduction of ultrasound, biochemical markers of liver function were important in differentiating surgical from medical jaundice. Their specificity and sensitivity were very poor and they are now only of historical interest. The main value of biochemistry nowadays is to quantify the severity and the duration of an obstruction and to monitor the effects of treatment.

Computed tomography (CT) has a limited place in the imaging of common duct stones. The ultrasound examination may raise the possibility of a malignant obstruction, and a CT scan may be obtained before ERCP. CT detects dilatation of the ducts very reliably (Fig. 14) 1237, and it is slightly better than ultrasound at identifying the site and the cause of an obstruction.

The prothrombin time is a marker of coagulation and should always be measured, even if the patient is not jaundiced. Patients with a prolonged prothrombin time should receive vitamin K and may also require fresh frozen plasma to correct a coagulation defect before embarking on an endoscopic sphincterotomy.

Any patient who has any degree of jaundice and a fever must have blood cultures taken before treatment with antibiotics. This may be the only opportunity to identify an organism.

It can still be very difficult to differentiate medical from surgical causes of jaundice and hepatitis occasionally develops in patients who also have stones in the ducts. As soon as this is suspected the immunological markers for hepatitis must be measured, and the laboratory must be warned.

In a patient suspected of having stones in the bile duct and in whom dilatation of the ducts is seen on ultrasound, ERCP should be undertaken unless the patient is to proceed directly to surgery. In most patients this will confirm the diagnosis and allow the stones to be removed through a sphincterotomy (Fig. 40) 1263. A detailed description of ERCP and sphincterotomy is given in Section 27.2. In certain circumstances percutaneous cholangiography is also helpful and other interventional techniques are sometimes needed. Once stones are discovered in the bile duct there should be little delay in removing them. The choice generally lies between an operation or an endoscopic sphincterotomy: the best approach primarily depends on whether or not the patient has undergone previous cholecystectomy.

Surgical removal is the most appropriate treatment for young or middle-aged patients without serious coexisting disease and with uncomplicated ductal stones. The morbidity and mortality associated with surgical exploration of the bile duct and endoscopic sphincterotomy are very similar in this group of patients, and most of them need their gallbladder removed anyway. Preoperative endoscopic clearance of the ducts may reduce the total time spent in hospital, but it has no other advantage and the risk of long-term complications from sphincterotomy is unknown.

Patients over the age of 60, poor-risk patients, and those with complicated ductal stones are best treated endoscopically. The morbidity and mortality associated with endoscopic treatment is much less in this group of patients, and only 1 in 10 elderly patients need subsequent cholecystectomy. Patients between the ages of 50 and 60 have to be treated on their individual merits.

Patients with retained or recurrent stones following cholecystectomy should be treated endoscopically in the first instance, whatever their age. Retained stones are those detected soon after a choledochotomy. Residual stones come to light months or years later. ERCP and sphincterotomy are required as soon as retained stones are found, particularly if they have been deliberately left behind. They are occasionally difficult to remove, particularly if the ducts are small and if the stones lie above the t-tube. Some stones can only be removed once the t-tube has itself been removed, and time must pass to allow the t-tube track to mature before this is safe. Retained stones may pass spontaneously, and they can occasionally be flushed through the ampulla with saline, or dissolved by a solution with stone-dissolving properties; none of these techniques is totally reliable. Extracting retained stones along the mature t-tube track under radiological control (Burhenne technique) is very effective in skilled hands, but the patient has to keep his or her tube and its attendant bag for 6 weeks while the track matures. None of the methods is perfect, and a combination of a percutaneous and an endoscopic technique may be needed. Residual stones, which are often large, require a generous endoscopic sphincterotomy and removal of the stones with a basket or balloon (Fig. 40) 1263. Occasionally it is difficult to obtain a cholangiogram or to insert the sphincterotomy knife into the bile duct. Provided there is no doubt about the clinical diagnosis and the ultrasound findings, cutting into the ampulla with a needle knife is justified. This is a dangerous manoeuvre because of the risk of perforation, but once a small cut is made the proper knife will then enter the bile duct and the cut can be extended to a full sphincterotomy in order to extract the stones. Diverticula of the duodenum, which are more common in old age, can be a nuisance as they distort the anatomy of the ampulla and the distal bile duct.

The overall success in clearing the bile duct is about 85 per cent. Large stones are difficult to remove. The limitations of modern technology must be realized: conventional exploration of the common bile duct must be advised if appropriate. Alternatively, it may be possible to reduce the size of the stones with crushing baskets, stone-dissolving agents, or lithotripters. None of these methods work for everyone, all work sometimes. In very elderly and frail people insertion of a plastic stent into the bile duct is excellent palliation. The stent allows drainage of bile and prevents impaction of the stone.

These stones may be suspected before operation or may appear unexpectedly on the operative cholangiogram (Fig. 33) 1256. It is normally appropriate to remove all the stones from the duct at one operation, but there are some exceptions. Small stones in small ducts, particularly if they are impacted at the ampulla, may be best left alone. The former may pass spontaneously whilst impacted stones should be extracted endoscopically after leaving a t-tube in the duct for safety. Similarly in poor risk patients it might be appropriate simply to close the wound, perhaps with a t-tube, and to arrange a prompt endoscopic extraction.

The action required when stones are discovered in the bile duct during a laparoscopic cholecystectomy is not yet clear. One option is simply to convert the operation to an open procedure and to remove the stones in the conventional way. Another is to complete the cholecystectomy, leave a drain in the abdomen, and perform an endoscopic sphincterotomy within a few days. Experts can clear the bile duct of stones laparoscopically, and in time this may well become the standard procedure.

Stones can be removed from the duct surgically, either from above (the supraduodenal approach) or from below (the transduodenal approach). Occasionally both approaches are needed together. The transduodenal operation has been largely superseded by the endoscopic approach which is safer and easier.

Following cholecystectomy and operative cholangiography the common bile duct is exposed above the duodenum. It is not necessary to expose the duct completely for fear of damaging the blood supply but it is helpful to mobilize the second part of the duodenum (Kocher's manoeuvre). The site of the choledochotomy should be as proximal as possible to allow choledochoduodenostomy if required and to leave the greatest length of bile duct above the choledochotomy against the unlikely possibility of the need for repair of a postoperative bile duct stricture.

Two stay sutures are placed on either side of the proposed choledochotomy and the duct is opened longitudinally along the anterior wall (Fig. 43) 1266. A sample of bile is sent for culture. Following careful removal of any obvious stones, the ducts are then flushed with an umbilical catheter. Choledochoscopy with either a rigid or a flexible instrument is then performed, first upwards into the intrahepatic ducts (Fig. 44) 1267 and then downwards to the ampulla. The saline infusion not only provides a view (Fig. 45) 1268 but also washes stones and debris out of the ducts. It is easier to see the intrahepatic ducts and much more difficult to be sure that the retroduodenal portion of the bile duct is clear of stones. Desjardin's forceps, a Fogarty balloon catheter, and a Dormia basket may all be helpful in extracting stones. The ampulla should never be dilated with metal bougies. They rarely dilate the ampulla but usually create a fistula into the duodenum immediately above the ampullary opening. Very narrow choledochoscopes with an outside diameter of 3 mm are now available. These pass down the cystic duct into the bile duct and they can be used through a laparoscope port.

Some surgeons like to repeat the cholangiogram to confirm that the duct has been cleared. However, it is difficult to obtain satisfactory pictures and the failure to remove all the stones at an exploration is not regarded as an error. It is sometimes safer and wiser to leave a difficult stone behind for later retrieval than to cause damage to the bile duct by prolonged attempts at its removal.

Once all the stones and debris have been removed a 16 Fg guttered latex t-tube is placed in the common bile duct. The free end is brought out laterally through the abdominal wall. This position keeps the radiologist's hands away from the X-ray beam during cholangiography, and the size of tube will allow percutaneous extraction of a retained stone if this becomes necessary. The choledochotomy is then closed with a fine absorbable suture and a drain is placed in the subhepatic space prior to closure of the wound.

Postoperatively the t-tube is allowed to drain freely into a sterile, closed, drainage bag. A t-tube cholangiogram is obtained 9 or 10 days after surgery (Fig. 46) 1269 and, if the duct is clear, the t-tube is clamped. Provided the patients does not develop any pain or discomfort the tube can be removed 24 h later. Drainage from the t-tube site usually ceases within 48 h.

In this operation the bile duct is approached across the duodenum and through the ampulla. It is usually combined with a sphincteroplasty. The duodenum is fully mobilized and a longitudinal incision is made in the right lateral wall over the ampulla. A probe is then passed into the bile duct and the ampullary sphincter is divided with scissors. Fine catgut sutures are placed to appose the mucosa of the bile duct to the duodenum and the stones are then extracted with Desjardin forceps. The choledochoscope can be used to ensure that all the stones have been removed and the duodenum is then closed. The advantage of this approach is that any missed stone will pass spontaneously. The disadvantage is the risk of pancreatitis from interference with the ampulla. Most patients who need a transampullary approach to their bile ducts are better treated endoscopically.

Occasionally an alternative to closure of the common bile duct over a t-tube after a supraduodenal exploration is a choledochoduodenostomy. Provided the bile duct is more than 15 mm in diameter the operation is quick and easy to perform, and there are no worries about retained stones. The vertical incision in the common bile duct is sutured to a longitudinal incision in the duodenum with a single layer of stitches. Results in elderly patients are satisfactory, but in patients who have had the anastomosis for a number of years recurrent cholangitis may develop. This is known as the ‘sump syndrome’: infection arises from stones and vegetable matter which collect in the retroduodenal portion of the bile duct between the anastomosis and the ampulla. There may also be stenosis of the choledochoduodenostomy. Endoscopic sphincterotomy of the ampulla and balloon dilatation of the anastomosis may alleviate the symptoms, but treatment is not very satisfactory.

Percutaneous cholangiography is the most common cause of bile peritonitis, although there is usually blood present as well. Provided the signs are localized treatment can be conservative, although if there is a significant biliary obstruction it is likely that the leak will persist. It is still wise to perform percutaneous cholangiography only when it is also possible to relieve any obstruction, either radiologically or at an operation within 12 h.

Occasionally the acutely inflamed gallbladder perforates and fills the peritoneum with bile; this may also happen if a t-tube is removed too soon. Bile peritonitis can be difficult to diagnose clinically because uninfected bile is often not particularly irritant and the signs may be very subdued. Once the diagnosis is made laparotomy is usually needed, but for smaller more localized collections, as may occur after a percutaneous cholangiogram, ultrasound guided drainage may be sufficient.

Almost all injuries to the bile ducts occur during an easy cholecystectomy; the most common mistake is to confuse the common hepatic duct for the cystic duct. The ‘duct’ is tied and divided, thus excising a length of the common hepatic duct in the hilum of the liver (Fig. 38) 1261. A similar injury can occur during laparoscopic cholecystectomy. Very few patients have undergone operative cholangiography.

Poor surgical technique is the most common cause of a significant biliary injury. The precise individual anatomy has not been correctly identified, although various anatomical and pathological factors may have made this difficult. The surgeon thinks that narrow ducts are too narrow to be the bile duct. The cystic duct may run alongside the bile duct for a distance, which leads the surgeon into the wrong plane. Anatomical variations of the main ducts also predispose to damage. The cystic duct may enter the right hepatic duct; sometimes there is no right duct, and the right anterior hepatic duct runs very close to the cystic duct. Such anatomical variations are one of the justifications for performing operative cholangiography. During the operation excessive fibrosis and inflammation in the porta hepatis and sudden inadvertent haemorrhage are both dangerous and put the bile ducts at risk.

Inadequate exposure is the cause of most injuries. An adequate and correctly placed initial incision is essential Excessive traction is to be avoided and it is not necessary to trace the cystic duct right to the junction with the bile duct. Once any difficulty is encountered a cholangiogram is invaluable.

Two new operations have increased the risks of bile duct injury. Minicholecystectomy is undertaken through the smallest possible incision and exposure is therefore minimal. Dissection must stay immediately adjacent to the gallbladder wall until the cystic duct is reached. Correctly performed, the operation is safe, but there is no margin for error. Failure to identify the anatomy correctly is associated with the bile duct injuries which occur at laparoscopic cholecystectomy, but the causes are different. The two-dimensional television image causes difficulties in orientation and judgement of depth, and the necessary manual skills are strange to most surgeons. Exposure is not normally a problem and indeed the view of the anatomy, particularly in obese patients, is excellent (Fig. 35) 1258. If difficulty is encountered nothing must be divided until the anatomy is clear. A cholangiogram may help and an open operation must be undertaken if this would be a safer option.

In about one-quarter of patients the injury is recognized at the time of operation and in a further third it comes to light within the next month. Most of these latter patients present with jaundice, sometimes with cholangitis and sometimes with a biliary fistula. The remaining patients present months or years later with recurrent cholangitis. In the early postoperative period ERCP is the most useful imaging technique for displaying the extent of the damage; this may provide an opportunity to place a stent if this is appropriate. Contrast medium injected along the track of a fistula may define the injury and the bile ducts adequately.

In patients who present later, both ERCP and percutaneous transhepatic cholangiography may be needed to display the superior and the inferior aspects of the stricture. It may also be possible to relieve the obstruction by placing a self expanding metal stent across the structure. These patients with long-standing incomplete obstruction and infection have a significant risk of liver damage and portal hypertension. The presence and the severity of these complications require investigations such as a liver biopsy and oesophagoscopy looking for varices.

Many surgeons realize with horror during a cholecystectomy that they have just tied the bile duct. The tie should be removed and nothing further needs to be done. Strictures do not develop afterwards.

A serious injury may take one of three forms. First, there may be a short incision into the bile duct, perhaps with a ragged edge if tearing was a feature of the injury. This is commonly caused by inferior traction on the cystic duct at the junction with the bile duct. Second, the bile duct may be divided clean across, perhaps obliquely, but there is no loss of length. Third, a portion of the duct may be excised.

Most surgeons are able to deal with the first two injuries. In the first, the incision can be closed directly with fine absorbable sutures, over a t-tube if necessary. In the second case the bile duct should be repaired with interrupted fine absorbable sutures over a t-tube (Fig. 47) 1270. A t-tube should never be brought out through the damaged area of duct because the irritation, inflammation, and fibrosis is likely to increase the risk of subsequent stricture. It must always be placed through a separate stab incision above or below the repair.

The best results of treatment of the third type of injury are obtained if an experienced biliary surgeon is called to help. If a complete length of duct has been excised only a tiny stump of hepatic duct is likely to remain, and the wisest course is to reconstruct the biliary system at once with an hepaticojejunostomy to a Roux loop of jejunum. With experience a choledochoduodenostomy may be safe, but there is always the risk of excessive tension on the anastomosis and a subsequent stricture. Partial excision of one wall of the duct is the most dangerous injury of all. It is tempting to mobilize the duct above and below and to suture the defect transversely over a t-tube. Experience is required to judge whether the degree of tension is excessive. If there is any doubt an hepaticojejunostomy is safer.

Patients who present at any time after the original operation should be referred to a specialist unit. The first requirement is to control any sepsis by drainage of pus and appropriate antibiotics, and to ensure free drainage of bile so far as this is possible. It is then necessary to establish the precise nature and extent of the damage. The anatomy of all the bile ducts inside and outside the liver must be defined, and an arteriogram is essential if surgical reconstruction is planned. It is not uncommon to find concomitant damage to the hepatic artery or the portal vein. Many of these patients are malnourished and need parenteral nutrition. There should be no hurry to perform surgery.

The objective of treatment is to achieve long-term unobstructed drainage of bile to the bowel. Drainage can be achieved in several ways, but usually means a direct mucosa to mucosa anastomosis of the bile duct to a Roux loop of jejunum. There is a definite place for endoscopic or percutaneous balloon dilatation or stenting of a stricture, certainly as a temporary measure and occasionally as definitive treatment in high-risk patients. Inadequate treatment of a stricture is dangerous. The patient's symptoms may improve but there is nevertheless a slow and progressive deterioration in liver function, which ultimately proves fatal.

The best results are obtained when a bile duct injury is discovered immediately and when a suitable tension-free repair is performed, which heals with minimal scarring. The worst results arise in patients who have undergone multiple previous repairs and who have evidence of liver failure and portal hypertension. Injuries in the porta hepatis have a worse prognosis than more proximal damage probably because they are technically more difficult to repair.

The operative mortality is at least 5 per cent and uncontrollable haemorrhage and renal failure are common causes of death, often associated with infection and an external biliary fistula. Many patients experience one or more major complications. Bile duct repairs are notorious for the formation of a recurrent stricture. In the past about one in three patients could expect further trouble; recently this has fallen to one in 10 patients. Despite the difficulties they should be offered a further attempt at operation: previous failure does not preclude a successful outcome.

Narrowing of the bile duct is often seen at ERCP in association with chronic inflammation in or around the duct usually from bile duct stones and sometimes from chronic pancreatitis. In patients with stones the stricture tends to be in the retroduodenal portion of the duct, and the important point from the endoscopist's point of view is to be sure that the stone will come through the narrow area if it is engaged in a basket. Failure to realize this problem is the most common cause of a trapped basket during attempted endoscopic removal of a bile duct stone (Fig. 48) 1271. Significant and short inflammatory strictures of the duct appear to respond well to balloon dilatation, although if dilatation fails surgery is needed. Rarely, chronic pancreatitis may cause narrowing of the proximal bile duct. Jaundice developing during an acute exacerbation usually fades spontaneously. When there is evidence of long-term obstruction from severe fibrosis, an end-to-side choledochoduodenostomy is necessary.

The incidence of this condition is controversial. The main symptom that leads to investigation is episodic pain with features which strongly suggest a biliary origin. Most of these patients will have undergone previous cholecystectomy. There are no absolute diagnostic criteria, but the most useful are the combination of abnormal liver function tests, dilatation of the bile duct, delayed emptying of contrast, and difficulty in cannulating the ampulla at an ERCP performed by an experienced endoscopist. In specialist units manometric studies of ampullary function and special provocation tests may help to identify these patients and indicate those who will benefit from a sphincterotomy. The precise histological changes are uncertain, but in most cases there is excessive fibrosis and inflammation of both the mucosa and the muscle of the ampulla. If the diagnosis is well established before operation the results are good.

Sclerosing cholangitis is characterized by an obliterative inflammatory fibrosis of the biliary tract that leads to chronic liver disease. Sometimes the fibrosis is clearly secondary to stones in the bile duct or previous biliary surgery, but primary sclerosing cholangitis, in which these predisposing causes are absent, is a disease entity on its own. The appearance on cholangiography is diagnostic, although occasionally only time will exclude cholangiocarcinoma (Fig. 49) 1272. Primary sclerosing cholangitis was regarded as a rare disease but the advent of ERCP has resulted in greater recognition of the condition.

The cause of primary sclerosing cholangitis is unknown. The association with ulcerative colitis in two-thirds of patients suggests that chronic low-grade portal bacteraemia or the absorption of toxic bile acids from the diseased colon might be significant aetiological factors, but neither hypothesis has much experimental support. Recently, phenotyping studies have shown a much higher frequency of HLA-B8, DR3, DQ2, and DRw52A in patients with primary sclerosing cholangitis than in controls. These findings not only confirm the role of genetic factors but also suggest that the disease is immunologically mediated, as this phenotype is closely associated with a number of autoimmune diseases. Overall, current evidence suggests that primary sclerosing cholangitis is an immunologically mediated disease, perhaps triggered in genetically susceptible subjects by acquired toxic or infectious agents.

Men are twice as commonly affected as are women and most patients present between the ages of 25 and 40. The usual symptoms are fatigue, intermittent jaundice, weight loss, upper abdominal pain, and pruritus. Attacks of acute cholangitis are surprisingly rare, unless there has been instrumental biliary intervention. Approximately half of all symptomatic patients have jaundice or hepatosplenomegaly. Many patients are discovered because of an abnormally high alkaline phosphatase on routine testing, usually during investigation of ulcerative colitis. Serum levels of bilirubin and alkaline phosphatase are usually elevated, the latter more than the former. These levels also fluctuate during the course of the disease. The cholangiogram is diagnostic, with typical beading from irregular stricturing and dilatation of both the intra- and extrahepatic ducts (Fig. 49) 1272. Occasionally only the intrahepatic ducts are involved; very rarely the disease affects only the extrahepatic system. Liver histology is not often diagnostic. The early features are periductal fibrosis, portal oedema, and bile ductular proliferation. Later fibrosis spreads into the liver parenchyma leading ultimately to biliary cirrhosis. Although primary sclerosing cholangitis and ulcerative colitis are closely linked the course of each disease is apparently independent. The colitis usually extends throughout the colon but causes few symptoms. Colectomy makes no difference to the course of the cholangitis.

There is no curative treatment. Trials of corticosteroids, immunosuppressants, cholecystogogues, and antibiotics, either alone or in combination, have been universally disappointing. Management is directed towards minimizing symptoms and treating complications. Pruritus responds to cholestyramine; antibiotics are needed during episodes of cholangitis. Mechanical relief of a well-defined stricture is well worthwhile. In many patients the best approach is to place a stent across the obstruction either percutaneously or endoscopically. Balloon dilatation of the strictures may also be very effective.

Surgical treatment is controversial. Resection of extrahepatic strictures and reconstruction over Silastic stents produces good results in some series, but orthotopic liver transplantation is the only option available to young patients with primary sclerosing cholangitis and advanced liver disease. Recently, a 4-year survival rate of 70 per cent in 75 transplanted patients has been reported.

The average time between the onset of symptoms and death is about 7 years, and most patients die from hepatic failure. About one-quarter of patients with primary sclerosing cholangitis eventually develop a bile duct carcinoma, which frequently follows a very aggressive course.

Leakage of bile from the biliary tract can occur from the liver, the gallbladder, or the bile duct itself, and it may leak to the skin via the peritoneum or to the bowel. Some fistulae are created deliberately, such as a choledochoduodenostomy. Others develop from a pathological process, either from surgical complications, from ulceration of a stone, or from drainage of pus into an adjacent structure.

The most common external fistula develops following surgery. Even after a straightforward cholecystectomy there may be a little bile in the drain the following day. Larger volumes of bile occasionally drain, presumably because the tie on the cystic duct stump has slipped. Providing a stone has not been left in the bile duct and that there is no other cause of biliary obstruction the volume will decrease and the fistula will close spontaneously.

A t-tube in the common bile duct is technically a fistula. Normally a cholangiogram will be performed before the t-tube is removed to confirm that there is free flow into the duodenum; the fistula closes rapidly once the t-tube is removed. Any delay in closure implies some degree of obstruction, such as a residual stone, and an ERCP is necessary.

The late development of a fistula after an open cholecystectomy almost always signifies unrecognized damage to the bile duct and comes to light after the drainage of an abscess (Fig. 50) 1273. These patients are usually ill and septic. They need careful evaluation and investigation before any further surgical intervention. Biliary leaks from the cystic duct stump are a complication of laparascopic cholecystectomy. Placing a stent in the bile duct at ERCP normally stops these leaks at once.

Severe cholangitis occasionally leads to an intrahepatic abscess, which ruptures first into the perihepatic peritoneum. Biliary peritonitis rarely ensues because of surrounding adhesions, but when the abscess is drained externally a fistula results. Such a fistula will only close when the proximal obstruction that caused the cholangitis is removed or relieved. This may not be possible with a malignant obstruction.

Any significant bile loss externally is accompanied by rapid fluid and electrolyte depletion which must be vigorously replaced. If the patient will tolerate it bile can be returned to the bowel via a nasogastric tube.

Spontaneous internal fistulae are uncommon and are usually discovered at cholecystectomy when a communication between the gallbladder and the duodenum becomes apparent as Hartmann's pouch is dissected away from the bowel. This usually results when a stone has ulcerated into the duodenum and disappeared in the faeces. There are no specific symptoms to suggest that this has happened, except when a large stone escapes and impacts in the terminal ileum, giving rise to gallstone ileus. Rarely, the stone ulcerates into the stomach or the colon. In the latter instance patients have profuse diarrhoea as the bile is irritant to the colon.

The treatment is to remove the gallbladder and to close the hole in the bowel. It is very rarely necessary to resect the bowel, but it is wise to leave a drain in the wound.

A specific type of cholangitis occurs in patients of Asiatic or Oriental origin, affecting predominantly the intrahepatic bile ducts, which contain soft stones and strictures (see also Sections 41.5 171 and 41.6 172). The left hepatic system is more frequently affected than is the right, and liver abscesses are a common complication. Both sexes are affected equally, and the condition presents at a younger age than Western cholelithiasis. The gallbladder is only inflamed in about one-fifth of patients, and it rarely contains stones.

Infection of small biliary radicles by bowel organisms, probably from an episode of gastroenteritis, is thought to be the cause. The disease is more common in malnourished people and in some populations there is an association with infection by Clonorchis sinensis and Ascaris lumbricoides. Bacterial enzymes split soluble conjugated bilirubin, forming bilirubinate sludge. Strictures of the ducts are also a constant feature, but it is uncertain whether the stones or the strictures appear first.

The primary pathology is in the bile ducts, and the liver is involved secondarily. In the acute stage the liver is oedematous and there is inflammation around the portal tracts and thrombophlebitis of the portal veins. After recurrent attacks the bile ducts become thickened and stenosed, surrounded by fibrous tissue and a chronic inflammatory infiltrate. Secondary changes develop in the liver.

A clinical diagnosis is easy to make in the right context. There are typical symptoms of recurrent cholangitis in a young patient of Asian or Oriental origin and signs of chronic hepatic infection. Viral hepatitis is the principal differential diagnosis. Ultrasound and ERCP are the main diagnostic investigations required, but blood culture and examination of the stools for parasites are also important.

Treatment of the acute stage is directed at controlling the infection with intravenous fluids and antibiotics. Surgery is avoided unless the patient's condition deteriorates because of septicaemia from severe obstruction or generalized peritonitis from pancreatitis, rupture, or an empyema of the gallbladder, or rupture of a distended hepatic duct on the surface of the liver. Acute operations are directed at draining the biliary tree with a t-tube through a choledochotomy after clearing the duct of as many stones as possible.

Elective surgery is intended to remove the stones from the biliary tract and to relieve any strictures that are present. This is difficult and tedious surgery, because the stones are very soft and do not wash away easily. On occasion some form of limited hepatic resection may be the best form of treatment; this is particularly useful if only the left hepatic system is diseased. Most surgeons also remove the gallbladder. As the name implies the disease tends to recur with time although the ultimate prognosis is very unpredictable. When complications develop the outlook is poor.

The liver is the most common site for a hydatid cyst in man (see also Section 41.8 173). Such cysts grow slowly in size and about two-thirds of patients present with simple hepatomegaly. Of the remainder one in eight are found by accident and a similar number present with biliary colic and transient jaundice due to rupture of the cyst into the biliary tree. Attention is mostly directed towards treatment of the primary cyst, which includes treatment with drugs which kill the parasite. Imaging of the biliary system is important. If hydatid elements are present in the ducts they must be removed through a choledochotomy at the same time as removal of the main cyst. Choledochoscopy before closure is useful to ensure that the duct is clear, and the choledochotomy is then closed over a t-tube. Sometimes it is wise to perform a transduodenal sphincteroplasty to ensure free drainage of any residual hydatid material into the bowel. Nowadays it might be easier to do this endoscopically soon after removal of the cyst. Occasionally, a biliary fistula persists after removal of hydatid cyst: ERCP and sphincterotomy with removal of any daughter cysts or hydatid debris from the bile ducts should allow the fistula to close.

Neoplasia of the biliary tract is uncommon. Carcinoma of the gallbladder and bile duct appear infrequently, and benign tumours are decidedly rare.

Polyps in the gallbladder are sometimes seen on ultrasound or on a cholecystogram. The majority of these are cholesterol polyps or adenomyomas and are not, therefore, true tumours. If gallstones are also present and causing symptoms then the patient needs a cholecystectomy. If they are an isolated finding most surgeons believe that they sometimes cause symptoms; provided these are sufficiently severe surgery is justified. If surgery is not appropriate and the polyps are large they should be monitored radiologically, and removal is advised if they enlarge.

True adenomas do occur and they have a malignant potential. This is most likely to occur if they are larger than 10 mm in diameter and sessile. Such patients require cholecystectomy.

Papillomas of the bile duct occur most commonly at the ampulla and are usually small. They present with biliary tract obstruction or recurrent pancreatitis. ERCP reveals the lesion unfolding into the duodenum as the sphincterotomy is made. These lesions are usually regarded as premalignant, and they should be removed either surgically or endoscopically. Papillomas are sometimes multiple and when crowded together look like a villous adenoma (Fig. 51) 1274. These lesions tend to recur and to become malignant. It is obviously important to remove them; depending on their site in the biliary tract and their extent, this may require an hepatic resection.

Admirand WH, Small DM. The physicochemical basis of cholesterol gallstone formation in man. J Clin Invest 1968; 47: 1043–52.

Aldridge MC, Bismuth H. Gallbladder cancer: the polyp-cancer sequence. Br J Surg 1990; 77: 363–4.

Armstrong CP, Taylor TV, Jeacock J, Lucas S. The biliary tract in patients with acute gallstone pancreatitis. Br J Surg 1985; 72: 551–5.

Ashby BS. Acute and recurrent torsion of the gallbladder. Br J Surg 1965; 52: 182–4.

Baron RL, et al. A prospective comparison of the evaluation of biliary obstruction using computed tomography and ultrasonography. Radiology 1982; 145: 91–8.

Belli L, Del Favero E, Marni A, Romani F. Resection versus pericystectomy in the treatment of hydatidosis of the liver. Am J Surg 1983; 145: 239–42.

Benbow EW. Xanthogranulomatous cholecystitis. Br J Surg 1990; 77: 255–6.

Blumgart LH, ed. Surgery of the Liver and Biliary Tract. Edinburgh: Churchill Livingstone, 1988.

Blumgart LH, Kelley CJ, Benjamin IS. Benign bile duct stricture following cholecystectomy: critical factors in management. Br J Surg 1984; 71: 836–43.

Bodvall B. The postcholecystectomy syndromes. Clin Gastroenterol 1973; 2: 103–26.

Bouchier IAD. Gall stones. Br Med J 1990; 300: 592–7.

Boyden EA. The anatomy of the choledochoduodenal junction in man. Surg Gynecol Obstet 1957; 104: 641–52.

Burhenne HJ. Percutaneous extraction of retained biliary tract stones: 661 patients. Am J Roentgenol 1980; 134: 888–98.

Chapman RW, et al. Primary sclerosing cholangitis—a review of its clinical features, cholangiography and hepatic histology. Gut 1980; 21: 870–7.

Chen HH, Zhang WH, Wang SS. Twenty-two year experience with the diagnosis and treatment of intrahepatic calculi. Surg Gynecol Obstet 1984; 159: 519–24.

Chiverton SG, Inglis JA, Hudd C, Kellet MJ, Russell RCG, Wickham JEA. Percutaneous cholecystolithotomy: the first 60 patients. Br Med J 1990; 300: 1310–2.

Cooperberg PL, Burhenne HJ. Real-time ultrasonography. Diagnostic technique of choice in calculous gallbladder disease. N Engl J Med 1980; 302: 1277–9.

Cotton PB. Progress Report ERCP. Gut 1977; 18: 316–41.

Couinaud C. Le Foie: Études Anatomiques et Chirurgicales. Paris: Masson & Cie, 1957: 9–12.

Csendes A, Carlos Diaz J, Burdiles P, Maluenda F, Nava O. Mirizzi syndrome and cholecystobiliary fistula: a unifing classification. Br J Surg 1989; 76: 1139–43.

Degenshein GA. Choledochoduodenostomy, an 18 year study of 175 consecutive cases. Surgery 1974; 76: 319–24.

DeMarco A, Nance FC, Cohn I. Chronic cholecystitis: experience in a large charity institution. Surgery 1968; 63: 750–6.

Doyle PJ, Ward-McQuaid JN, McEwen-Smith A. The value of routine peroperative cholangiography: a report of 4000 cholecystectomies. Br J Surg 1982; 69: 617–9.

Fox MS, Wilk PJ, Weissman HS, Freeman LM, Gliedman ML. Acute acalculous cholecystitis. Surg Gynecol Obstet 1984; 159: 13–16.

Glenn F. A 26 year experience in the surgical treatment of 5037 patients with non-malignant biliary tract disease. Surg Gynecol Obstet 1959; 109: 591–606.

Glenn F. Acute cholecystitis. Surg Gynecol Obstet 1976; 143: 56–60.

Glenn F, Reed C, Grafe WR. Biliary enteric fistula. Surg Gynecol Obstet 1981; 153: 527–31.

Gough MH. ‘The cholecystogram is normal’—but—. Br Med J 1977; 274: 960–2.

Gracie WA, Ransohoff DF. The natural history of silent gallstones. The innocent gallstone is not a myth. N Engl J Med 1982; 307: 798–800.

Hand BH. An anatomical study of the choledochoduodenal area. Br J Surg 1963; 50: 486–94.

Howard ER, Driver M, McClement JW, Mowat AP. Results of surgery in 88 consecutive cases of extrahepatic biliary atresia. J R Soc Med 1982; 75: 408–13.

Kameda H, the Tokyo Co-operative Gallstone Study Group. Efficacy and indications of ursodeoxycholic acid treatment for dissolving gallstones. A multi-centre double-blind trial. Gastroenterology 1980; 78: 542–8.

Keighley MRB. Micro-organisms in the bile. A preventable cause of sepsis after biliary surgery. Ann R Coll Surg Engl 1977; 59: 328–34.

Kune GA, Sali A. The Practice of Biliary Surgery. 2nd edn. Oxford: Blackwell Scientific Publications, 1980.

Leow CK, Thompson MH. Endoscopic papillotomy without cholecystectomy for bile duct stones. Ann R Coll Surg Engl 1986; 68: 300–1.

Le Quesne LP, Ranger I. Cholecystitis glandularis proliferans. Br J Surg 1957; 44: 447–58.

Levine SB, Lerner HJ, Leifer ED, Lindheim SR. Intraoperative cholangiography: a review of indications and analysis of age-sex groups. Ann Surg 1983; 198: 692–7.

Matolo NM, ed. Biliary Tract Disease. Surg Clin N Am 1981; 61: 763–994.

May RE, Strong R. Acute emphysematous cholecystitis. Br J Surg 1971; 58: 453–8.

McArthur P, Cuscheiri A, Sells RA, Shields R. Controlled clinical trial comparing early with interval cholecystectomy for acute cholecystitis. Br J Surg 1975; 62: 850–2.

McClement JW, Howard ER, Mowat AP. Results of surgical treatment for extrahepatic biliary atresia in the United Kingdom 1980–1982. Br Med J 1985; 290: 345–7.

Mentzer RM Jnr, Golden GT, Chandler JG. A comparative appraisal of emphysematous cholecystitis. Am J Surg 1975; 129: 10–15.

Mirizzi PL. Operative cholangiography. Surg Gynecol Obstet 1937; 65: 702–10.

Mitchell A, Morris PJ. Trends in the management of acute cholecystitis. Br Med J 1982; 284: 27–30.

Motson RW, Wetter LA. Operative choledochoscopy: common bile duct exploration is incomplete without it. Br J Surg 1990; 77: 975–82.

Mueller PR, Harbin WP, Ferrucci JT, Wittenberg J, Van Sonnenberg E. Fine needle transhepatic cholangiography: reflections after 450 cases. Am J Roentgenol 1981; 136: 85–90.

Nardi GL, Michelassi F, Zannini P. Transduodenal sphincteroplasty 5–25 year follow-up of 89 patients. Ann Surg 1983; 198: 453–61.

Neoptolemos JP, Carr-Lock DL, Fossard DP. Prospective randomised study of preoperative endoscopic sphincterotomy versus surgery alone for common bile duct stones. Br Med J 1987; 294: 470–4.

Neoptolemos JP, Carr-Locke DL, London N, Bailey I, Fossard DP. ERCP findings and the role of endoscopic sphincterotomy in acute gallstone pancreatitis. Br J Surg 1988; 75: 954–60.

Northover JMA, Terblanche J. A new look at the arterial supply of the bile duct in man and its surgical implications. Br J Surg 1979; 66: 379–84.

O'Connor MJ, Schwartz ML, McQuarrie DG, Sumner HW. Acute bacterial cholangitis. An analysis of clinical manifestation. Arch Surg 1982; 117: 437–41.

Porayko MK, et al. Patients with asymptomatic primary sclerosing cholangitis frequently have a progressive disease. Gastroenterology 1990; 98: 1594–602.

Robertson HE. Silent gallstones. Gastroenterology 1945; 5: 345–72.

Ruddell WSJ, Ashton MG, Lintott DJ, Axon ATR. Endoscopic retrograde cholangiography and pancreatography in investigation of post-cholecystectomy patients. Lancet 1980; i: 444–7.

Sackmann M, Delius M, Sauerbruch T. Shock-wave lithotripsy of gall bladder stones: the first 175 patients. N Engl J Med 1988; 318: 393–7.

Safrany L, Cotton PB. A preliminary report: urgent duodenoscopic sphincterotomy for acute gallstone pancreatitis. Surgery 1981; 89: 424–8.

Saharia PC, Zuidema GD, Cameron JL. Primary common duct stones. Ann Surg 1977; 185: 598–604.

Sarles H, Sahel J. Cholestasis and lesions of the biliary tract in chronic pancreatitis. Gut 1978; 19: 851–7.

Schein CJ, Gliedman ML. Choledochoduodenostomy as an adjunct to choledocholithotomy. Surg Gynecol Obstet 1981; 152: 797–804.

Schoenfeld LJ, Lachin JM. Chenodiol (chenodeoxycholic acid) for dissolution of gallstones: the National Cooperative Gallstone Study. A controlled trial of efficacy and safety. Ann Intern Med 1981; 95: 257–82.

Scragg RKR, McMichael AJ, Baghurst PA. Diet, alcohol, and relative weight in gall stone disease: a case-control study. Br Med J 1984; 288: 1113–9.

Scragg RKR, McMichael AJ, Seamark RF. Oral contraceptives, pregnancy, and endogenous oestrogen in gall stone disease—a case-control study. Br Med J 1984; 288: 1795–9.

Shanahan D, Lord PH, Grogono J, Wastell C. Clinical acute cholecystitis and the Curtis Fitz-Hugh syndrome. Ann R Coll Surg Engl 1988; 70: 44–6.

Smith EEJ, Bowley N, Allison DJ, Blumgart LH. The management of post-traumatic intrahepatic cutaneous biliary fistulas. Br J Surg 1982; 69: 317–8.

Smith L. Injuries of the liver, biliary tree and pancreas. Br J Surg 1978; 65: 673–7.

Soloway RD, Trotman BW, Ostrow JD. Pigment stones. Gastroenterology 1977; 72: 167–82.

Southern Surgeons Club. A prospective analysis of 1518 laparoscopic cholecystectomies. N Engl J Med 1991; 324: 1073–8.

Spitz L. Choledochal cyst. Surg Gynecol Obstet 1978; 147: 444–52.

Stanley RJ, Melson GL, Cubillo E, Hesker AE. A comparison of three cholecystographic agents. A double-blind study with and without a prior fatty meal. Radiology 1974; 112: 513–7.

Stubbs RS. Wound infection after cholecystectomy: a case for routine prophylaxis. Ann R Coll Surg Engl 1983; 65: 30–1.

Sykes D. The use of cholecystokinin in diagnosing biliary pain. Ann R Coll Surg Engl 1982; 64: 114–16.

Taylor TV, Armstrong CP. Migration of gall stones. Br Med J 1987; 294: 1320–2.

Thornton J, Heaton KW, Espiner HJ, Eltringham WK. Empyema of the gall bladder: reappraisal of a neglected disease. Gut 1983; 24: 1183–5.

Todani T, Watanabe Y, Narusue M, Tabuchi K, Okajima K. Congenital bile duct cysts: classification, operative procedures, and review of thirty-seven cases including cancer arising from choledochal cyst. Am J Surg 1977; 134: 263–8.

Toouli J. Sphincter of Oddi motility. Br J Surg 1984; 71: 251–6.

Vellacott KD, Powell PH. Exploration of the common bile duct: a comparative study. Br J Surg 1979; 66: 389–91.

Viceconte G, Viceconte GW, Pietropaolo V, Montori A. Endoscopic sphincterotomy: indications and results. Br J Surg 1981; 68: 376–80.

Warshaw AL, Simeone J, Schapiro RH, Hedberg SE, Mueller PE, Ferrucci JT. Objective evaluation of ampullary stenosis with ultrasonography and pancreatic stimulation. Am J Surg 1985; 149: 65–72.

Wenckert A, Robertson B. The natural course of gallstone disease. Gastroenterology 1966; 50: 376–81.