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Choledochal cysts: Experience with radical excision
Choledochal Cysts : Experience with Radical Excision By PETER G. JONES,E. DURHAMSMITH,A. MURRAYCLARKE,ANDMAXWELLKENT
A
CHOLEDOCHAL CYST is still to some extent an enigma; the etiology is uncertain, the clinical history is episodic, appropriate investigations may yield negative results during remissions, and the operative procedures usually employed are not always entirely successful in relieving symptoms completely. The cystic dilatation of the bile ducts appears to be congenital, and causes symptoms during childhood although the progress of the pathologic changes does not appear to be necessarily related to age. At the Royal Children’s Hospital, Melbourne, a choledochal cyst has been successfully excised in five consecutive cases in the last 2 years, and these are the basis for this report. CASE REPORTS Care 1: J. M., a 3-year-old girl, was admitted in December 1967, with a history of intermittent vomiting for 6 we&s, accompanied by diarrhea, listlessness, pallor, and irritability. Her general health had been good, but she had “always been inclined to biliousness since infancy.” For 4 weeks before admission she had pruritis, pale stools, and dark urine, although there was no icterus of the skin. A diffuse, nontender mass was palpable in the epigastrium. A choledochal cyst or hydatid of the liver was suspected, the latter because of a high eosinophil count and positive Casoni and hydatid complement fixation tests. Liver function tests and radiographs of the chest and abdomen were normal. Operation: At laparotomy (E.D.S.) a large tense choledochal cyst 11 cm in diameter
presented above the duodenum. The gallbladder and the cystic duct were very distended. The cystic dilation of the common bile duct extended downwards from the junction of the right and left hepatic ducts as far as its junction with the duodenum, which was displaced forward (Fig. 1A). An easily dissected plane of areolar tissue was found between the peritoneum and the anterior wall of the cyst and it was decided that the cyst should be excised. The plane was developed by blunt dissection, opening a space between the adjacent walls of cyst and duodenum, but sharp dissection was finally required at the junction of the cyst with the duodenal wall. After disconnecting the cyst, there was a very small opening in the duodenum at the point of entry of the common bile duct, and this opening was oversewn with one
stitch. The cyst was then lifted forward and dissected away from the hepatic artery and the portal vein, The excision was completed by dividing the enlarged common hepatic duct, leaving a segment 2 cm in diameter and 1 cm long (Fig. 1B). The dilated cystic duct had become incorporated in the wall of the cyst and so cholecystectomy was also performed. The proximal end of the common hepatic duct was then anastomosed end-to-end to a loop
From the Royal Children’s Hospital, Melbourne, Australia. PETER G. JONES, M.S., F.R.C.S., F.R.A.C.S.: Surgeon, the Royal Children’s Hospital, Melbourne, Australia. E. DVRHAM SMITH, M.D., F.R.A.C.S.: Surgeon, the Royal Children’s Hospital, Melbourne, Australia. A. MVRRAY CLARKE, F.R.C.S., F.R.A.C.S., D.C.H.: Senior Surgeon, the Royal Children’s Hospital, Melbourne, Australia. MAXWELL KENT, F.R.A.C.S.: Surgeon, the Royal Children’s Hospital, Melbourne, Australia.
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Fig. l.-(A) Diagram of the anatomy in Cases 1, 2, and 3. GB: gallbladder; L: liver; CHD: common hepatic duct; P: pylorus C: colon. (B) Case 1. The proximal end of the divided common hepatic duct. (C) Cases 1, 2, 3. The Roux-en-Y choledochojejunostomy created after excision of the choledochal cyst. of jejunum (en-Y) (Fig. 1C) and the anastomosis was facilitated by the almost equal dimensions of the duct and the bowel. The abdomen was closed leaving a drain tube down to the site of the anastomosis. There WRS no biliary drainage and no rise of temperature. The color of the stools and urine returned to normal on the fourth day and she left hospital on the tenth day after operation. She remains perfectly well 3 years later. Histology: The wall of the cyst was composed mostly of dense fibrous tissue, but there were quite well developed bundles of smooth muscle still identifiable in places. The cyst was lined by columnar epithelium resembling that of the normal bile duct, and there were large areas of ulceration and patchy inflammatory infiltration. The gallbladder showed some fibrosis and chronic inflammatory changes. Case 2: A. S., a healthy I-year-old boy, was admitted in January 1966, with peri-umbilical colic and an indefinite mass palpable beneath the right costal margin. He had vomited once, and tenderness without guarding was present in the epigastrium. All symptoms and signs subsided within 2 to 3 hrs. Similar attacks lasting 2 to 3 hrs. had occurred in the preceding 3 months. The results of the following investigations were normal: full blood examination, radiographs of the chest and abdomen, pyelography, urinalysis, and a barium meal. In the absence of any positive findings, no exploration was performed. In 1968 he returned, aged 4 years, with another attack, the second in the 2 years since the previous admission. On this occasion a firm cystic mass was palpable extending 5 cm below the right costal margin. Next morning the mass was no longer palpable and all symptoms and signs had disappeared. A choledochal cyst was suspected and this was confirmed by ( 1) a barium meal, which showed that the pylonrs, the duodenal cap, and the whole duodenal loop were displaced to the left and slightly downward (Fig. 2A) and (B) and intravenous cholangiogram, which showed “incomplete filling suggestive of obstruction somewhere in the extrahepatic biliary system.” Operation: At exploration (P.G.J.) in February 1988, a large cyst, roughly circular and 9 cm in diameter occupied the space between the duodenum and the undersurface of the liver (Fig. 1A). The gallbladder and to a lesser extent the cystic and common hepatic ducts were slightly distended. The cyst extended behind the second part of the duodenum which was displaced forwards and to the left. The cyst also extended upwards behind the right and left hepatic ducts; the common hepatic duct, 2 cm in diameter and length, entered the anterior surface of the cyst obliquely.
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Fig. 2.-C&e 2. (A) Barium meal showing displacement of the pylorus and fist part of the duodenum downwards and to the left in the AP view. (B) Lateral view showing forward displacement of the first part of the duodenum, and the choledochal cyst outlined by all segments of the duodenum.
Fig. 3.-Case 2. Operative specimen showing the absorption of the cystic duct into the wall of the cyst. CHD: Site of connection with the common hepatic duct, and D: the attachment of the cyst to the second part of the duodenum. There was again a dissectable areolar plane around the cyst, which was then totally mobilized and excised without difficulty (Fig. 3). Particular care was taken in detaching the lower pole, which narrowed sharply to enter the wall of the duodenum in the center of an annulus of flattened pancreatic tissue. The small deficiency in the wall of the duodenum was readily closed with two layers of fine atraumatic silk sutures. The proximal end of the common hepatic duct was then anastomosed to a standard Roux-en-Y loop of jejunum brought through the base of the transverse mesocolon (Fig. 1B). The abdomen was closed with a drain tube to the site of the biliary anastomosis. The dram tube was removed on the third day, after the escape of a small amount of slightly bile-tinged serous fluid. On the fifth day there was a rise in puke rate and some upper abdominal tenderness, but the serum amylase and urinary diastase were within normal limits and the further convalescence was unintermpted. He left hospital on the tenth day and has been in perfect health for 2 years.
CHOLEDOCHAL
Histology:
115
CYSTS
The wall of the cyst was mainly fibrous with some scattered
fibers. The lining was partly ulcerated and partly composed of flattened lium. There were also a few areas of patchy inflammatory infiltration.
bundles biliary
of muscle
duet epithe-
Case 3: K. W., a girl, presented in 1966 at the age of 7 years with upper abdominal pain and swelling, present for 3 weeks, and occasional bouts of abdominal pain for some years, but she had never been jaundiced. On examination
she was pale, thin, and afebrile.
The abdomen
was generally
protruberant,
and tenderness with guarding precluded accurate palpation of the upper abdomen. A firm liver edge was palpable 6 cm below both costal margins. Under anesthesia a cystic swelling about the size of an orange was palpable, separate from the liver edge and extending beneath the right rectus. She was not jaundiced clinically; serum bilirubin was 1.0 mg/lOO ml, and transaminase levels were elevated. First Operation: At laparotomy ( M. K.) there was a large choledochal cyst 14 cm in diameter; the gallbladder was distended and connected to the mass by an enlarged cystic duct. Dissection in the porta hepatis revealed a dilated common hepatic duct 4 cm in diameter and continuous with the cyst. On opening the cyst, clear golden bile escaped. The wall was fibrous and there were many pigment concretions, some free, and many attached to the lining of the cyst. An anastomosis of the cyst to the adjacent second part of the duodenum was performed, creating a wide stoma. A liver biopsy was obtained and showed mild biliary fibrosis. The subsequent course was uneventful for 2 weeks, but then an attack of cholangitis occurred accompanied by fever, pain, and jaundice. This resolved in response to antibiotics. In the next 2% years there were five further episodes of cholangitis with fever, pain, repeated vomiting, and mild jaundice. In June 1969, she was admitted for reexploration. There were no abnormal clinical findings, the transaminase levels were normal, and radiographic investigations (barium meal, cholangiography ) failed to outline the choledochal cyst. Second Operation: The original cyst was represented by a dense mass of fibrous tissue 5 X 5 cm surrounding an irregular cavity containing biliary concretions. The anastomosis with the duodenum was taken down and the cyst was excised, together with the distended cystic duct and gallbladder. Careful dissection was necessary to preserve the hepatic artery and portal vein. The upper pole of the cyst was freed by transecting the common bile duct just below the confluence of the right and left hepatic ducts, leaving a segment 2 cm long with a lumen 3 cm in diameter which was anastomosed end-to-end with a Roux-en-Y loop of jejunum. Postoperative recovery was uneventful and there have been no symptoms in the 12 months since operation. Histology: The wall of the cyst was composed of dense fibrous tissue with scattered of chronic’inflammatory infiltration and was devoid of a recognisable epithelial lining. Biopsy
of the liver showed
a mild biliary
areas
fibrosis.
Case 4: J. J. was thought to have had hepatitis at the age of 18 months. One year later symptoms recurred, accompanied by intermittent jaundice. At the age of 5% years she again became anorexic; the urine was dark, and the stools pale. Progressive distension of her abdomen was noted and a firm mass, thought to be the liver, extended 6 cm below the right costal margin, A provisional diagnosis of chronic hepatitis was contraindicated by a total serum bilirubin of 2.3 mg/lOO ml, bilirubin 0.9 mg/lOO ml, thymol turbidity: 2 units, serum transaminase: normal. First Operation: At laparotomy ( A.M.C.) a choledochal cyst 12 cm in diameter was found and confirmed by an operative cholangiogram via the gallbladder. An anastomosis between the cyst and the adjacent duodenum was made. In the following 7 years she suffered six attacks of colicky abdominal pain and associated nausea, vomiting and sweating, in spite of long-term broad spectrum antibiotics. Some were
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mild and her general health was good. Very little schooling was lost, but admission to hospital was required on three occasions. Tests of liver function and liver biopsy were consistent with mild cholangitis, and barium meals showed widely dilated biliary passages containing barium, and, at other times, gas. Second Operation: At the age of 13 years, 8 years after the anastomosis, the abdomen was re-opened (A.M.C.). There were dense adhesions between the bowel and the liver and surrounding the cyst, now shrunken and thick-walled. Dissection around the cyst was difficult because of vascularity caused by chronic infection. The common bile duct, 2 cm in diameter, was divided as the final step excising the cyst which was removed with considerable difficulty. The small opening ( 0.5 cm) into the duodenum was Ased, and reinforced with a cuff of
the adjacent cyst wall. The common hepatfc duct was then anastomosed end-to-end to a loop of jejunum (Roux-en-Y) and a drain tube was placed down to the site of the anastomosis.
Convalescence
hospital
2 weeks
was
after
somewhat
stormy
with
partial
ileus
and
fever,
but
she
left
operation.
Case 5: C. J., a baby girl of birth weight 4.41 kg, was admitted at the age of ‘7 weeks in June 1969, with jaundice since birth and subject to minor variations in intensity. The stools were almost white and the urine was dark. Under the right costal margin and below the liver edge there was a firm, nontender mass which extended to below the umbilicus. A needle biopsy of the liver indicated obstruction in the biliary tract, a barium meal showed a large rounded posterior mass expanding the C-shaped curve of the duodenum (a~ in Fig. 2), and a diagnosis of choledochal cyst was made. Operation: At 11 weeks of age, laparotomy ( A.M.C. ) revealed a large tense cyst 10 X 8 cm with the duodenum covering the medial third. The cystic duct was dilated, but the gallbladder was normal in size. The common hepatic duct was 1.25 cm in diameter, and an operative cholangiogram showed ducts of normal size and pattern in the liver. The gallbladder and the cystic duct were mobilized, and the common hepatic duct was transected 1 cm below the junction of the right and left hepatic ducts. The extension of the cyst behind the duodenum was then easily freed by blunt dissection, assisted by pledgets soaked in hyaluronidase. The opening of the cyst into the duodenum could not be found, even by probing from inside the cyst, although the cholangiogram showed that there was a small communicating channel. A small segment of the cyst wall attached to the duodenum was left in place and oversewn in several layers to seal the site of the opening. An end-to-end anastomosis of the common hepatic duct to the end of a loop of jejunum (Roux-en-Y) was then performed, the vertical arm passing lateral to the hepatic flexure. abdomen was closed, leaving a drain tube down to the site of the anastomosis. Convalescence was uneventful and she left hospital 15 days and has thrived throughout the 12 months since operation. Histology: The wall of the cyst was composed of fibrous tissue; no muscle fibers could be
The
identified,
and there was no recognizable
epithelial
lining.
The wall of the gallbladder
was
hypoplastic. hXUSSION This
series has yielded
firms the preponderance
no
new evidence
of the type
( Fig.
concerning 1)
all five cases belonged. Histologic examination
of four of the specimens
of the mucosa
degrees
ing scattered distance
apart,
of various bundles
of smooth
of severity muscle
the etiology,
classified
but con-
as Group I1 to which
excised
showed
ulceration
and dense fibrous tissue contain-
fibers. The muscle
but this could have been spatial separation
expansion of the wall of the duct. Three extensive reviews of the literature a-4 have brought
fibers were
some
due to considerable the total number
CHOLEDOCHAL
CYSTS
117
of reported cases to 500 and, except where stated, the percentages quoted below are based on this number. The incidence in pediatric hospitals has been estimated as approximately 1 per 13,000 admissions,5 and the cases in our series represent a figure of approximately 1 per 15,000 total admissions. The incidence is apparently four times higher in Japan5 and approximately one-third of all the 500 reported cases occurred in Orientals.4 A female preponderance of about 4:I has been consistently noted in the literature and this was the figure in our small series. The age group affected is primarily infants and young children, and approximately 50 to 60% of patients are less than 10 years old when the final diagnosis is made. The clinical presentation varies, and in pediatric practice falls into two groups: 1. Infants with jaundice, who present with features similar to neonatal hepatitis and atresia of the bile ducts. 2. Older children with intermittent attacks of pain, nausea, vomiting and/or fever, jaundice, or a palpable mass in the upper part of the abdomen. The typical triad of jaundice ( 67%)) pain ( 60%)) and a palpable mass (50%) is well known, but only about 20% of patients have all three symptoms or signs. The attacks are usually of short duration and the symptoms often indefinite. When jaundice is not present to draw attention to the biliary tract, the diagnosis is quite commonly not made during the first few episodes. It is further handicapped in some cases by the early and rapid disappearance of symptoms and signs, and by the fact that the diagnostic investigations largely depend upon the cyst being large and tense, and this may be intermittent, of short duration, and occur at long intervals. Investigations that have proved most helpful are chiefly radiologic. A barium meal is diagnostic when the duodenum is displaced to the left and downward (Fig. 2). Oral or intravenous cholangiography is on the whole rather disappointing; it is not worthwhile when the patient has jaundice, and even when there is no obstruction, dilution of the dye in a cyst with a large capacity (for example, up to 8 liters) prevents a clear picture of the duct system. However, failure to delineate the biliary tract in a cholangiogram is itself an indication that there is some abnormality. Aortography or selective arteriography, now established as a means of investigating abdominal masses in childhood, may contribute to the diagnosis of choledochal cysts, but due to the relative lack of large vessels in the cyst wall, there is little to see except displacement of viscera, which can be demonstrated without angiography. In several subsequently proven cases, thorough investigation has yielded negative results, and the tests should be repeated if further attacks occur. Tests of liver function usually show no abnormality, but are helpful in excluding hepatitis. The surgical treatment has greatly improved since 1935 when the operative
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mortality was quoted8 as 80 to 90%. In 91 cases treated between 1959 and 1969 the operative mortality was 5Z.4 Repeated aspiration or external drainage are as unacceptable as a definitive procedure today as they were lethal in the past-83 to 100% mortality.7 An exception may be temporary external drainage as an emergency procedure in a severely toxic or jaundiced patient too ill to tolerate a definitive operation. Cystoduodenostomy, the technique requiring the least dissection, has been favored by some, s-r0 but there is a significant incidence of later complications, perhaps as high as 30 to 60%.r,rr-ra A small stoma may become stenotic and lead to recurrent obstruction, while a wide anastomosis tends to cause free reflux of duodenal contents into the proximal bile ducts and recurring attacks of cholangitis (Cases 3 and 4). Cystojejunostomy (Roux-en-Y) has become the most widely adopted procedure,s-sF7*14-1s but even when the anastomosis is constructed so as to promote free dependent drainage, early or late complications can occur,a,s, 15, la chiefly recurrent attacks of ascending cholangitis. Excision of the cyst has only recently become more popular, having been condemned in the past 8, rs,sO+sr because of “sudden death,” during operation or following prolonged “postoperative shock.” It has been suggested3 that the mortality may arise not so much from the excision itself as from inadvisable attempts to reconstruct the common bile duct. The operative mortality has also been related3715 to whether the correct diagnosis had been made before operation ( 30%, as opposed to 56% when incorrect). In an emergency situation, that is, without adequate investigations and in inexperienced hands, an attempt to excise a choledochal cyst, without recognizing the nature of the condition, could well lead to disaster. Excision was suggested as early as 1924,22 by others in the past1+r2 and again more recently.23-26 Difficulty in mobilizing the cyst probably varies with the severity of fibrosis around it. In some cases the fibrosis or the configuration of the cyst might well would then be the better choice. prohibit excision, and cystojejunostomy Nevertheless, a trial dissection, commencing on the anterior or right lateral aspect of the cyst, is feasible and if a plane of dissection cannot be developed, the attempt could be abandoned without prejudice to an alternative procedure. This was the plan in all five cases reported here. Dissection around the cyst was comparatively easy in the first two patients. When a secondary procedure became necessary in two other cases, because of recurrent symptoms following cystoduodenostomy, it was found that in these, too, the cyst could be dissected from the surrounding tissues and excised, though with more difficulty than when performed as a primary procedure. Some of the technical points may be worth mentioning: 1. The pancreatic duct was not identified in any of the five cases despite careful dissection. It may have opened into the duodenum separately, but more probably it was preserved in its intramural course to the ampulla of Vater; 2. The anterior and right lateral aspects of the cyst were freed first, then
CHOLEDOCHAL
119
CYSTS
the attachment to the duodenum, preceded by partial decompression of the cyst by aspiration. When freed from the duodenum and drawn upward to the right, the cyst was dissected from the hepatic artery and portal vein. 3. The common hepatic duct was left until last, after mobilizing the gallbladder and cystic duct. A favorable aspect of all of our cases was the moderate enlargement in diameter and thickness of the wall of the common hepatic duct. In each case these dimensions were almost exactly the same as the cut end of the jejunum and this simplified the anastomosis. 4. Choledochojejunostomy was performed first, having divided the jejunum and brought the distal end through the base of the transverse mesocolon. The jejunojejunostomy was then made, at the most appropriate point below the mesocolon, so as to avoid any laxity or kinking in either arm of the Y (Fig. 1C). Re-establishment of biliary drainage after excision is probably most suitably provided in this way. Alternatives such as choledochoduodenostomy or choledochodochostomy are probably undesirable, and rarely possible, although there is a reports3 of a case in which the common hepatic duct was successfully joined to the distal segment of common bile duct. When the necessary skills and facilities are available, that is, competent pediatric anesthesia, operative cholangiography, accurate estimates of blood lost, and careful maintenance of circulating volume, fluids, and electrolytes, excision should probably be attempted in most cases. The lack of any or all of these facilities could account for the occasional deaths which have been reported following excision. Excision, when feasible, is recommended because: 1. It is in accord with the basic surgical principle of removing a dilated channel with an inflamed mucosa and ineffectual musculature, factors which favor stasis, infection, and the formation of calculi. 2. It can be combined with a jejunal Roux loop as a primary procedure which, it is hoped, will prove to be more effective in preventing late complications and recurrent symptoms in the long-term view, which is essential in childhood. 3. It can be performed in early infancy when the diagnosis is made in this age group. 4. It is still possible as a secondary procedure when an anastomosis of the cyst to the alimentary tract has failed to prevent stasis, stenosis or reflux. Experience in these five cases has shown that it can be safely performed in each of these situations. If a long-term followup of our patients and in others treated in the same way indicates that there is a low incidence of late complications, excision may become the operation of choice in the treatment of choledochal cysts. However, it may not be possible in all cases, and cholecystojejunostomy would then be the next best choice. ACKNOWLEDGMENT We are indebted to Dr. H. G. Hiller, Director of Radiology, for his assistance in diagnosis, Dr. P. E. Campbell for reports on the histolbgy and the Department of Photography for the illustrations.
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JONES ET AL.
REFERENCES 1. Alonso-Lej, F., Rever, W. B., Jr., and Pessagno, D. J.: Congenital choledochal cyst with a report of 2 and an analysis of 94 cases. Int. Abstr. Surg. 108:1, 1959. 2. Shallow, T. A., Eger, S. A., and Wagner, F. B., Jr.: Congenital cystic dilatation of the common bile duct: case report and review of the literature. Ann. Surg. 1117:355, 1943. 3. Tsardakas, E. and Robnett, A. H.: Congenital cystic dilatation of the common bile duct: Report of three cases, analysis of 57 cases and review of the literature. Arch. Surg. 72:311, 1956. 4. Lee, S. S., Min, P. C., Kim, G. S., and Hong, P. W.: Choledochal cyst: A report of nine cases and review of the literature. Arch. Surg. 99:19, 1969. 5. Hays, D. M., Goodman, G. N., Snyder, W. H., and Woolley, M. W.: Congenital cystic dilatation of the common bile duct. Arch. Surg. 98:457, 1969. 6. Dickson Wright, A.: Xray appearances produced by congenital dilatation of the common bile duct. Brit. J. Radiol. 8:227, 1935. 7. Attar, S. and Obeid, S.: Congenital cyst of the common bile duct: A review of the literature and a report of two cases. Ann. Surg. 142:289, 1955. 8. Gross, R. E.: Surgery of Infancy and Chikdhood. Philadelphia, Saunders 1955. 9. Daniel, D. S.: Choledochal cyst. Report of a case. Ann. Surg. 155:902, 1962. 10. Fonkalsrud, E. W. and Boles, E. T., Jr.: Choledochal cysts in infancy and childhood. Surg. Gynec. Obst. 121:733, 1965. 11. Hertxler, J. H. and Maguire, C. E.: Congenital dilatation of the common bile duct. AMA Arch. Surg. 62:275, 1951. 12. Arthur, G. W. and Stewart, J.O.R.: Biliary cysts. Brit. J. Surg. 51:671, 1964. 13. Ferris, D. 0. and YaDeau, R. E.: Choledochal cyst. Mayo CIin. Proc. 39:332, 1964.
14. Maingot, R.: Abdominal Operations. London, Saunders, 1955. 15. Ravitch, M. M. and Snyder, G. B.: Cystic dilatation of the common bile duct. Surgery 44 ~752, 1958. 16. Farrell, W. J.: Giant choledochal cyst. Report of a case successfully treated by a Roux-en-Y choledochal cyst-jejunostomy. Ann. Surg. 150:313,1959. 17. Warren, K. W. and Polk, R. C.: Benign cysts of the liver and bihary tract. Surg. Clin. N. Amer. 38:707, 1958. 18. Mahour, G. H. and Lynn, H. B.: Choledochal cyst in children. Surgery 65: 967, 1969. 19. Gilliland, M. B., Holloway, C. E. and Lange, J. H.: Congenital choledochal cyst. J. Pediat. 37:387, 1950. 20. Gillis, D. A. and Sergeant, C. K.: Prolonged biliary obstruction and massive gastrointestinal bleeding secondary to choledochal cysts. Surgery 52:391, 1962. 21. Keith, L. M. Jr., Rini, J. M., and Martin, L. H.: Congenital cystic dilatation of the common duct (choledochal cyst): report of two cases. Arch. Surg. 75:143, 1964. 22. McWhorter, G. L.: Congenital cystic dilatation of the common bile duct. Arch. Surg. 8:604, 1924. 23. Scharli, A. and Bettex, M.: Congenital choledochal cyst: Reconstruction of the normal anatomy. J. Pediat. Surg. 3:604, 1968. 24. Warren, K. W., Kune, G. A., and Hardy, K. J.: Bihary duct cysts. Surg. Clin. N. Amer. 48:567, 1968. 25. Suruga, Keijiro: Paper delivered before the Annual Meeting of the British Association of Paediatric Surgeons, Liverpool, 1968. 26. Kasai, M.: Fihn shown at Annual Meeting of the Pacific Association of Pediatric Surgeons, Melbourne, 1970.
A
CHOLEDOCHAL CYST is still to some extent an enigma; the etiology is uncertain, the clinical history is episodic, appropriate investigations may yield negative results during remissions, and the operative procedures usually employed are not always entirely successful in relieving symptoms completely. The cystic dilatation of the bile ducts appears to be congenital, and causes symptoms during childhood although the progress of the pathologic changes does not appear to be necessarily related to age. At the Royal Children’s Hospital, Melbourne, a choledochal cyst has been successfully excised in five consecutive cases in the last 2 years, and these are the basis for this report. CASE REPORTS Care 1: J. M., a 3-year-old girl, was admitted in December 1967, with a history of intermittent vomiting for 6 we&s, accompanied by diarrhea, listlessness, pallor, and irritability. Her general health had been good, but she had “always been inclined to biliousness since infancy.” For 4 weeks before admission she had pruritis, pale stools, and dark urine, although there was no icterus of the skin. A diffuse, nontender mass was palpable in the epigastrium. A choledochal cyst or hydatid of the liver was suspected, the latter because of a high eosinophil count and positive Casoni and hydatid complement fixation tests. Liver function tests and radiographs of the chest and abdomen were normal. Operation: At laparotomy (E.D.S.) a large tense choledochal cyst 11 cm in diameter
presented above the duodenum. The gallbladder and the cystic duct were very distended. The cystic dilation of the common bile duct extended downwards from the junction of the right and left hepatic ducts as far as its junction with the duodenum, which was displaced forward (Fig. 1A). An easily dissected plane of areolar tissue was found between the peritoneum and the anterior wall of the cyst and it was decided that the cyst should be excised. The plane was developed by blunt dissection, opening a space between the adjacent walls of cyst and duodenum, but sharp dissection was finally required at the junction of the cyst with the duodenal wall. After disconnecting the cyst, there was a very small opening in the duodenum at the point of entry of the common bile duct, and this opening was oversewn with one
stitch. The cyst was then lifted forward and dissected away from the hepatic artery and the portal vein, The excision was completed by dividing the enlarged common hepatic duct, leaving a segment 2 cm in diameter and 1 cm long (Fig. 1B). The dilated cystic duct had become incorporated in the wall of the cyst and so cholecystectomy was also performed. The proximal end of the common hepatic duct was then anastomosed end-to-end to a loop
From the Royal Children’s Hospital, Melbourne, Australia. PETER G. JONES, M.S., F.R.C.S., F.R.A.C.S.: Surgeon, the Royal Children’s Hospital, Melbourne, Australia. E. DVRHAM SMITH, M.D., F.R.A.C.S.: Surgeon, the Royal Children’s Hospital, Melbourne, Australia. A. MVRRAY CLARKE, F.R.C.S., F.R.A.C.S., D.C.H.: Senior Surgeon, the Royal Children’s Hospital, Melbourne, Australia. MAXWELL KENT, F.R.A.C.S.: Surgeon, the Royal Children’s Hospital, Melbourne, Australia.
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CHOLEDOCHAL CYSTS
113
Fig. l.-(A) Diagram of the anatomy in Cases 1, 2, and 3. GB: gallbladder; L: liver; CHD: common hepatic duct; P: pylorus C: colon. (B) Case 1. The proximal end of the divided common hepatic duct. (C) Cases 1, 2, 3. The Roux-en-Y choledochojejunostomy created after excision of the choledochal cyst. of jejunum (en-Y) (Fig. 1C) and the anastomosis was facilitated by the almost equal dimensions of the duct and the bowel. The abdomen was closed leaving a drain tube down to the site of the anastomosis. There WRS no biliary drainage and no rise of temperature. The color of the stools and urine returned to normal on the fourth day and she left hospital on the tenth day after operation. She remains perfectly well 3 years later. Histology: The wall of the cyst was composed mostly of dense fibrous tissue, but there were quite well developed bundles of smooth muscle still identifiable in places. The cyst was lined by columnar epithelium resembling that of the normal bile duct, and there were large areas of ulceration and patchy inflammatory infiltration. The gallbladder showed some fibrosis and chronic inflammatory changes. Case 2: A. S., a healthy I-year-old boy, was admitted in January 1966, with peri-umbilical colic and an indefinite mass palpable beneath the right costal margin. He had vomited once, and tenderness without guarding was present in the epigastrium. All symptoms and signs subsided within 2 to 3 hrs. Similar attacks lasting 2 to 3 hrs. had occurred in the preceding 3 months. The results of the following investigations were normal: full blood examination, radiographs of the chest and abdomen, pyelography, urinalysis, and a barium meal. In the absence of any positive findings, no exploration was performed. In 1968 he returned, aged 4 years, with another attack, the second in the 2 years since the previous admission. On this occasion a firm cystic mass was palpable extending 5 cm below the right costal margin. Next morning the mass was no longer palpable and all symptoms and signs had disappeared. A choledochal cyst was suspected and this was confirmed by ( 1) a barium meal, which showed that the pylonrs, the duodenal cap, and the whole duodenal loop were displaced to the left and slightly downward (Fig. 2A) and (B) and intravenous cholangiogram, which showed “incomplete filling suggestive of obstruction somewhere in the extrahepatic biliary system.” Operation: At exploration (P.G.J.) in February 1988, a large cyst, roughly circular and 9 cm in diameter occupied the space between the duodenum and the undersurface of the liver (Fig. 1A). The gallbladder and to a lesser extent the cystic and common hepatic ducts were slightly distended. The cyst extended behind the second part of the duodenum which was displaced forwards and to the left. The cyst also extended upwards behind the right and left hepatic ducts; the common hepatic duct, 2 cm in diameter and length, entered the anterior surface of the cyst obliquely.
114
JONES ET AL.
Fig. 2.-C&e 2. (A) Barium meal showing displacement of the pylorus and fist part of the duodenum downwards and to the left in the AP view. (B) Lateral view showing forward displacement of the first part of the duodenum, and the choledochal cyst outlined by all segments of the duodenum.
Fig. 3.-Case 2. Operative specimen showing the absorption of the cystic duct into the wall of the cyst. CHD: Site of connection with the common hepatic duct, and D: the attachment of the cyst to the second part of the duodenum. There was again a dissectable areolar plane around the cyst, which was then totally mobilized and excised without difficulty (Fig. 3). Particular care was taken in detaching the lower pole, which narrowed sharply to enter the wall of the duodenum in the center of an annulus of flattened pancreatic tissue. The small deficiency in the wall of the duodenum was readily closed with two layers of fine atraumatic silk sutures. The proximal end of the common hepatic duct was then anastomosed to a standard Roux-en-Y loop of jejunum brought through the base of the transverse mesocolon (Fig. 1B). The abdomen was closed with a drain tube to the site of the biliary anastomosis. The dram tube was removed on the third day, after the escape of a small amount of slightly bile-tinged serous fluid. On the fifth day there was a rise in puke rate and some upper abdominal tenderness, but the serum amylase and urinary diastase were within normal limits and the further convalescence was unintermpted. He left hospital on the tenth day and has been in perfect health for 2 years.
CHOLEDOCHAL
Histology:
115
CYSTS
The wall of the cyst was mainly fibrous with some scattered
fibers. The lining was partly ulcerated and partly composed of flattened lium. There were also a few areas of patchy inflammatory infiltration.
bundles biliary
of muscle
duet epithe-
Case 3: K. W., a girl, presented in 1966 at the age of 7 years with upper abdominal pain and swelling, present for 3 weeks, and occasional bouts of abdominal pain for some years, but she had never been jaundiced. On examination
she was pale, thin, and afebrile.
The abdomen
was generally
protruberant,
and tenderness with guarding precluded accurate palpation of the upper abdomen. A firm liver edge was palpable 6 cm below both costal margins. Under anesthesia a cystic swelling about the size of an orange was palpable, separate from the liver edge and extending beneath the right rectus. She was not jaundiced clinically; serum bilirubin was 1.0 mg/lOO ml, and transaminase levels were elevated. First Operation: At laparotomy ( M. K.) there was a large choledochal cyst 14 cm in diameter; the gallbladder was distended and connected to the mass by an enlarged cystic duct. Dissection in the porta hepatis revealed a dilated common hepatic duct 4 cm in diameter and continuous with the cyst. On opening the cyst, clear golden bile escaped. The wall was fibrous and there were many pigment concretions, some free, and many attached to the lining of the cyst. An anastomosis of the cyst to the adjacent second part of the duodenum was performed, creating a wide stoma. A liver biopsy was obtained and showed mild biliary fibrosis. The subsequent course was uneventful for 2 weeks, but then an attack of cholangitis occurred accompanied by fever, pain, and jaundice. This resolved in response to antibiotics. In the next 2% years there were five further episodes of cholangitis with fever, pain, repeated vomiting, and mild jaundice. In June 1969, she was admitted for reexploration. There were no abnormal clinical findings, the transaminase levels were normal, and radiographic investigations (barium meal, cholangiography ) failed to outline the choledochal cyst. Second Operation: The original cyst was represented by a dense mass of fibrous tissue 5 X 5 cm surrounding an irregular cavity containing biliary concretions. The anastomosis with the duodenum was taken down and the cyst was excised, together with the distended cystic duct and gallbladder. Careful dissection was necessary to preserve the hepatic artery and portal vein. The upper pole of the cyst was freed by transecting the common bile duct just below the confluence of the right and left hepatic ducts, leaving a segment 2 cm long with a lumen 3 cm in diameter which was anastomosed end-to-end with a Roux-en-Y loop of jejunum. Postoperative recovery was uneventful and there have been no symptoms in the 12 months since operation. Histology: The wall of the cyst was composed of dense fibrous tissue with scattered of chronic’inflammatory infiltration and was devoid of a recognisable epithelial lining. Biopsy
of the liver showed
a mild biliary
areas
fibrosis.
Case 4: J. J. was thought to have had hepatitis at the age of 18 months. One year later symptoms recurred, accompanied by intermittent jaundice. At the age of 5% years she again became anorexic; the urine was dark, and the stools pale. Progressive distension of her abdomen was noted and a firm mass, thought to be the liver, extended 6 cm below the right costal margin, A provisional diagnosis of chronic hepatitis was contraindicated by a total serum bilirubin of 2.3 mg/lOO ml, bilirubin 0.9 mg/lOO ml, thymol turbidity: 2 units, serum transaminase: normal. First Operation: At laparotomy ( A.M.C.) a choledochal cyst 12 cm in diameter was found and confirmed by an operative cholangiogram via the gallbladder. An anastomosis between the cyst and the adjacent duodenum was made. In the following 7 years she suffered six attacks of colicky abdominal pain and associated nausea, vomiting and sweating, in spite of long-term broad spectrum antibiotics. Some were
116
JONES ET AL.
mild and her general health was good. Very little schooling was lost, but admission to hospital was required on three occasions. Tests of liver function and liver biopsy were consistent with mild cholangitis, and barium meals showed widely dilated biliary passages containing barium, and, at other times, gas. Second Operation: At the age of 13 years, 8 years after the anastomosis, the abdomen was re-opened (A.M.C.). There were dense adhesions between the bowel and the liver and surrounding the cyst, now shrunken and thick-walled. Dissection around the cyst was difficult because of vascularity caused by chronic infection. The common bile duct, 2 cm in diameter, was divided as the final step excising the cyst which was removed with considerable difficulty. The small opening ( 0.5 cm) into the duodenum was Ased, and reinforced with a cuff of
the adjacent cyst wall. The common hepatfc duct was then anastomosed end-to-end to a loop of jejunum (Roux-en-Y) and a drain tube was placed down to the site of the anastomosis.
Convalescence
hospital
2 weeks
was
after
somewhat
stormy
with
partial
ileus
and
fever,
but
she
left
operation.
Case 5: C. J., a baby girl of birth weight 4.41 kg, was admitted at the age of ‘7 weeks in June 1969, with jaundice since birth and subject to minor variations in intensity. The stools were almost white and the urine was dark. Under the right costal margin and below the liver edge there was a firm, nontender mass which extended to below the umbilicus. A needle biopsy of the liver indicated obstruction in the biliary tract, a barium meal showed a large rounded posterior mass expanding the C-shaped curve of the duodenum (a~ in Fig. 2), and a diagnosis of choledochal cyst was made. Operation: At 11 weeks of age, laparotomy ( A.M.C. ) revealed a large tense cyst 10 X 8 cm with the duodenum covering the medial third. The cystic duct was dilated, but the gallbladder was normal in size. The common hepatic duct was 1.25 cm in diameter, and an operative cholangiogram showed ducts of normal size and pattern in the liver. The gallbladder and the cystic duct were mobilized, and the common hepatic duct was transected 1 cm below the junction of the right and left hepatic ducts. The extension of the cyst behind the duodenum was then easily freed by blunt dissection, assisted by pledgets soaked in hyaluronidase. The opening of the cyst into the duodenum could not be found, even by probing from inside the cyst, although the cholangiogram showed that there was a small communicating channel. A small segment of the cyst wall attached to the duodenum was left in place and oversewn in several layers to seal the site of the opening. An end-to-end anastomosis of the common hepatic duct to the end of a loop of jejunum (Roux-en-Y) was then performed, the vertical arm passing lateral to the hepatic flexure. abdomen was closed, leaving a drain tube down to the site of the anastomosis. Convalescence was uneventful and she left hospital 15 days and has thrived throughout the 12 months since operation. Histology: The wall of the cyst was composed of fibrous tissue; no muscle fibers could be
The
identified,
and there was no recognizable
epithelial
lining.
The wall of the gallbladder
was
hypoplastic. hXUSSION This
series has yielded
firms the preponderance
no
new evidence
of the type
( Fig.
concerning 1)
all five cases belonged. Histologic examination
of four of the specimens
of the mucosa
degrees
ing scattered distance
apart,
of various bundles
of smooth
of severity muscle
the etiology,
classified
but con-
as Group I1 to which
excised
showed
ulceration
and dense fibrous tissue contain-
fibers. The muscle
but this could have been spatial separation
expansion of the wall of the duct. Three extensive reviews of the literature a-4 have brought
fibers were
some
due to considerable the total number
CHOLEDOCHAL
CYSTS
117
of reported cases to 500 and, except where stated, the percentages quoted below are based on this number. The incidence in pediatric hospitals has been estimated as approximately 1 per 13,000 admissions,5 and the cases in our series represent a figure of approximately 1 per 15,000 total admissions. The incidence is apparently four times higher in Japan5 and approximately one-third of all the 500 reported cases occurred in Orientals.4 A female preponderance of about 4:I has been consistently noted in the literature and this was the figure in our small series. The age group affected is primarily infants and young children, and approximately 50 to 60% of patients are less than 10 years old when the final diagnosis is made. The clinical presentation varies, and in pediatric practice falls into two groups: 1. Infants with jaundice, who present with features similar to neonatal hepatitis and atresia of the bile ducts. 2. Older children with intermittent attacks of pain, nausea, vomiting and/or fever, jaundice, or a palpable mass in the upper part of the abdomen. The typical triad of jaundice ( 67%)) pain ( 60%)) and a palpable mass (50%) is well known, but only about 20% of patients have all three symptoms or signs. The attacks are usually of short duration and the symptoms often indefinite. When jaundice is not present to draw attention to the biliary tract, the diagnosis is quite commonly not made during the first few episodes. It is further handicapped in some cases by the early and rapid disappearance of symptoms and signs, and by the fact that the diagnostic investigations largely depend upon the cyst being large and tense, and this may be intermittent, of short duration, and occur at long intervals. Investigations that have proved most helpful are chiefly radiologic. A barium meal is diagnostic when the duodenum is displaced to the left and downward (Fig. 2). Oral or intravenous cholangiography is on the whole rather disappointing; it is not worthwhile when the patient has jaundice, and even when there is no obstruction, dilution of the dye in a cyst with a large capacity (for example, up to 8 liters) prevents a clear picture of the duct system. However, failure to delineate the biliary tract in a cholangiogram is itself an indication that there is some abnormality. Aortography or selective arteriography, now established as a means of investigating abdominal masses in childhood, may contribute to the diagnosis of choledochal cysts, but due to the relative lack of large vessels in the cyst wall, there is little to see except displacement of viscera, which can be demonstrated without angiography. In several subsequently proven cases, thorough investigation has yielded negative results, and the tests should be repeated if further attacks occur. Tests of liver function usually show no abnormality, but are helpful in excluding hepatitis. The surgical treatment has greatly improved since 1935 when the operative
118
JONES ET AL.
mortality was quoted8 as 80 to 90%. In 91 cases treated between 1959 and 1969 the operative mortality was 5Z.4 Repeated aspiration or external drainage are as unacceptable as a definitive procedure today as they were lethal in the past-83 to 100% mortality.7 An exception may be temporary external drainage as an emergency procedure in a severely toxic or jaundiced patient too ill to tolerate a definitive operation. Cystoduodenostomy, the technique requiring the least dissection, has been favored by some, s-r0 but there is a significant incidence of later complications, perhaps as high as 30 to 60%.r,rr-ra A small stoma may become stenotic and lead to recurrent obstruction, while a wide anastomosis tends to cause free reflux of duodenal contents into the proximal bile ducts and recurring attacks of cholangitis (Cases 3 and 4). Cystojejunostomy (Roux-en-Y) has become the most widely adopted procedure,s-sF7*14-1s but even when the anastomosis is constructed so as to promote free dependent drainage, early or late complications can occur,a,s, 15, la chiefly recurrent attacks of ascending cholangitis. Excision of the cyst has only recently become more popular, having been condemned in the past 8, rs,sO+sr because of “sudden death,” during operation or following prolonged “postoperative shock.” It has been suggested3 that the mortality may arise not so much from the excision itself as from inadvisable attempts to reconstruct the common bile duct. The operative mortality has also been related3715 to whether the correct diagnosis had been made before operation ( 30%, as opposed to 56% when incorrect). In an emergency situation, that is, without adequate investigations and in inexperienced hands, an attempt to excise a choledochal cyst, without recognizing the nature of the condition, could well lead to disaster. Excision was suggested as early as 1924,22 by others in the past1+r2 and again more recently.23-26 Difficulty in mobilizing the cyst probably varies with the severity of fibrosis around it. In some cases the fibrosis or the configuration of the cyst might well would then be the better choice. prohibit excision, and cystojejunostomy Nevertheless, a trial dissection, commencing on the anterior or right lateral aspect of the cyst, is feasible and if a plane of dissection cannot be developed, the attempt could be abandoned without prejudice to an alternative procedure. This was the plan in all five cases reported here. Dissection around the cyst was comparatively easy in the first two patients. When a secondary procedure became necessary in two other cases, because of recurrent symptoms following cystoduodenostomy, it was found that in these, too, the cyst could be dissected from the surrounding tissues and excised, though with more difficulty than when performed as a primary procedure. Some of the technical points may be worth mentioning: 1. The pancreatic duct was not identified in any of the five cases despite careful dissection. It may have opened into the duodenum separately, but more probably it was preserved in its intramural course to the ampulla of Vater; 2. The anterior and right lateral aspects of the cyst were freed first, then
CHOLEDOCHAL
119
CYSTS
the attachment to the duodenum, preceded by partial decompression of the cyst by aspiration. When freed from the duodenum and drawn upward to the right, the cyst was dissected from the hepatic artery and portal vein. 3. The common hepatic duct was left until last, after mobilizing the gallbladder and cystic duct. A favorable aspect of all of our cases was the moderate enlargement in diameter and thickness of the wall of the common hepatic duct. In each case these dimensions were almost exactly the same as the cut end of the jejunum and this simplified the anastomosis. 4. Choledochojejunostomy was performed first, having divided the jejunum and brought the distal end through the base of the transverse mesocolon. The jejunojejunostomy was then made, at the most appropriate point below the mesocolon, so as to avoid any laxity or kinking in either arm of the Y (Fig. 1C). Re-establishment of biliary drainage after excision is probably most suitably provided in this way. Alternatives such as choledochoduodenostomy or choledochodochostomy are probably undesirable, and rarely possible, although there is a reports3 of a case in which the common hepatic duct was successfully joined to the distal segment of common bile duct. When the necessary skills and facilities are available, that is, competent pediatric anesthesia, operative cholangiography, accurate estimates of blood lost, and careful maintenance of circulating volume, fluids, and electrolytes, excision should probably be attempted in most cases. The lack of any or all of these facilities could account for the occasional deaths which have been reported following excision. Excision, when feasible, is recommended because: 1. It is in accord with the basic surgical principle of removing a dilated channel with an inflamed mucosa and ineffectual musculature, factors which favor stasis, infection, and the formation of calculi. 2. It can be combined with a jejunal Roux loop as a primary procedure which, it is hoped, will prove to be more effective in preventing late complications and recurrent symptoms in the long-term view, which is essential in childhood. 3. It can be performed in early infancy when the diagnosis is made in this age group. 4. It is still possible as a secondary procedure when an anastomosis of the cyst to the alimentary tract has failed to prevent stasis, stenosis or reflux. Experience in these five cases has shown that it can be safely performed in each of these situations. If a long-term followup of our patients and in others treated in the same way indicates that there is a low incidence of late complications, excision may become the operation of choice in the treatment of choledochal cysts. However, it may not be possible in all cases, and cholecystojejunostomy would then be the next best choice. ACKNOWLEDGMENT We are indebted to Dr. H. G. Hiller, Director of Radiology, for his assistance in diagnosis, Dr. P. E. Campbell for reports on the histolbgy and the Department of Photography for the illustrations.
120
JONES ET AL.
REFERENCES 1. Alonso-Lej, F., Rever, W. B., Jr., and Pessagno, D. J.: Congenital choledochal cyst with a report of 2 and an analysis of 94 cases. Int. Abstr. Surg. 108:1, 1959. 2. Shallow, T. A., Eger, S. A., and Wagner, F. B., Jr.: Congenital cystic dilatation of the common bile duct: case report and review of the literature. Ann. Surg. 1117:355, 1943. 3. Tsardakas, E. and Robnett, A. H.: Congenital cystic dilatation of the common bile duct: Report of three cases, analysis of 57 cases and review of the literature. Arch. Surg. 72:311, 1956. 4. Lee, S. S., Min, P. C., Kim, G. S., and Hong, P. W.: Choledochal cyst: A report of nine cases and review of the literature. Arch. Surg. 99:19, 1969. 5. Hays, D. M., Goodman, G. N., Snyder, W. H., and Woolley, M. W.: Congenital cystic dilatation of the common bile duct. Arch. Surg. 98:457, 1969. 6. Dickson Wright, A.: Xray appearances produced by congenital dilatation of the common bile duct. Brit. J. Radiol. 8:227, 1935. 7. Attar, S. and Obeid, S.: Congenital cyst of the common bile duct: A review of the literature and a report of two cases. Ann. Surg. 142:289, 1955. 8. Gross, R. E.: Surgery of Infancy and Chikdhood. Philadelphia, Saunders 1955. 9. Daniel, D. S.: Choledochal cyst. Report of a case. Ann. Surg. 155:902, 1962. 10. Fonkalsrud, E. W. and Boles, E. T., Jr.: Choledochal cysts in infancy and childhood. Surg. Gynec. Obst. 121:733, 1965. 11. Hertxler, J. H. and Maguire, C. E.: Congenital dilatation of the common bile duct. AMA Arch. Surg. 62:275, 1951. 12. Arthur, G. W. and Stewart, J.O.R.: Biliary cysts. Brit. J. Surg. 51:671, 1964. 13. Ferris, D. 0. and YaDeau, R. E.: Choledochal cyst. Mayo CIin. Proc. 39:332, 1964.
14. Maingot, R.: Abdominal Operations. London, Saunders, 1955. 15. Ravitch, M. M. and Snyder, G. B.: Cystic dilatation of the common bile duct. Surgery 44 ~752, 1958. 16. Farrell, W. J.: Giant choledochal cyst. Report of a case successfully treated by a Roux-en-Y choledochal cyst-jejunostomy. Ann. Surg. 150:313,1959. 17. Warren, K. W. and Polk, R. C.: Benign cysts of the liver and bihary tract. Surg. Clin. N. Amer. 38:707, 1958. 18. Mahour, G. H. and Lynn, H. B.: Choledochal cyst in children. Surgery 65: 967, 1969. 19. Gilliland, M. B., Holloway, C. E. and Lange, J. H.: Congenital choledochal cyst. J. Pediat. 37:387, 1950. 20. Gillis, D. A. and Sergeant, C. K.: Prolonged biliary obstruction and massive gastrointestinal bleeding secondary to choledochal cysts. Surgery 52:391, 1962. 21. Keith, L. M. Jr., Rini, J. M., and Martin, L. H.: Congenital cystic dilatation of the common duct (choledochal cyst): report of two cases. Arch. Surg. 75:143, 1964. 22. McWhorter, G. L.: Congenital cystic dilatation of the common bile duct. Arch. Surg. 8:604, 1924. 23. Scharli, A. and Bettex, M.: Congenital choledochal cyst: Reconstruction of the normal anatomy. J. Pediat. Surg. 3:604, 1968. 24. Warren, K. W., Kune, G. A., and Hardy, K. J.: Bihary duct cysts. Surg. Clin. N. Amer. 48:567, 1968. 25. Suruga, Keijiro: Paper delivered before the Annual Meeting of the British Association of Paediatric Surgeons, Liverpool, 1968. 26. Kasai, M.: Fihn shown at Annual Meeting of the Pacific Association of Pediatric Surgeons, Melbourne, 1970.