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Fictitious pancreatitis in choledochal cyst
Fictitious Pancreatitis in Choledochal Cyst By Gustavo Stringel and Robert M. Filler Toronto, Ontario, Canada 9 The classical presentation of choledocal cyst has been regarded as a triad of abdominal pain. jaundice and a palpable abdominal mass; unusual presentations include rupture of the choledocal cyst with bile peritonitis, pancreatitis and bleeding esophageal varices. W e are reporting 3 children presenting clinically as recurrent acute pancreatitis with elevated serum amylase and found to have type I choledocal cyst. Despite elevated serum amylase there was no evidence of pancreatic inflammation at laparotomy. High amylase concentration was found in fluid contained within the cyst, This was probably responsible for the elevated serum amylase and also the inflammatory reaction seen in the wall of the choledocal cyst. These cases support the hypothesis that pancreatic reflux into the bile ducts is the etiological factor in the development of choledocal cyst, Our 3 cases were treated by cyst excision and have remained asymptomatic. The presence of hyperamylasemia should not delay appropriate surgical management. The treatment of choice is cyst excision, since it will eliminate factors contributing to the development of cholangitis and hyperamylasernia.
INDEX WORDS: Pancreatitis; choledochal cyst.
Y S T I C D I L A T A T I O N o f t h e b i l i a r y d u c t is r a r e a n d f a s c i n a t i n g e n t i t y w i t h 955 c a s e s r e p o r t e d in t h e w o r l d l i t e r a t u r e u p to 1975.1 T h e first d e s c r i p t i o n o f c h o l e d o c h a l cyst is a t t r i b u t e d to V a t e r in 1723; 2 in 1959 A l o n s o - L e j p u b l i s h e d an e x c e l l e n t r e v i e w o f c a s e s w i t h a s i m p l e c l a s s i f i c a t i o n ? H i s classification i n c l u d e d t h r e e t y p e s of cyst, all e x t r a h e p a t i c : T y p e I, t h e m o s t c o m m o n f o r m , also c a l l e d c o n g e n i t a l c y s t i c d i l a t a t i o n of t h e c o m m o n bile d u c t ; t y p e II or c o n g e n i t a l d i v e r t i c u l u m of t h e c o m m o n bile d u c t ; type III, congenital choledochocele. Subsequently other types of multiple and intrahepatic c y s t i c d i l a t a t i o n s h a v e b e e n a d d e d to A l o n s o L e j ' s o r i g i n a l c l a s s i f i c a t i o n 4'5'6 T h e classic p r e s e n t a t i o n of c h o l e d o c h a l cyst has b e e n r e g a r d e d as a t r i a d o f r i g h t u p p e r q u a d r a n t a b d o m i n a l pain, j a u n d i c e a n d a p a l p a ble a b d o m i n a l m a s s ; a b d o m i n a l p a i n b e i n g t h e m o s t f r e q u e n t finding. 3"7'8O t h e r u n u s u a l t y p e s o f presentation reported with increasing frequency include: r u p t u r e of t h e c h o l e d o c h a l cyst w i t h b i l e peritonitis, 9 p a n c r e a t i t i s , a n d s'l~ b l e e d i n g esop h a g e a l v a r i c e s d u e to b i l i a r y cirrhosis.
C
Journal of Pediatric Surgery, Vol. 17, No. 4 (August), 1982
CASE REPORTS
Case I LT., a 9 year old Japanese girl, had recurrent bouts of severe epigastric pain and vomiting since she was 3 yr old. She was admitted to another hospital on several occasions and found to have elevated serum amylase and she was treated as having acute pancreatitis. She was never jaundiced and liver function tests were normal; there was no palpable mass on physical examination. Type I choledochal cyst w a s diagnosed by intravenous cholangiogram which was obtained to see if the patient had gallstones. The cyst was successfully treated by excision and Roux en u choledocho-jejunost0my. The amylase content of the bile in the choledochal cyst was found to be over 32,000 somogyi units. She did very well after the procedure and was discharged home 18 days after the operation and in follow up after three years she was doing very well with no recurrence of the abdominal pain. Case 2 B.M., a 15 year old Caucasian girl, presented with a 3 mo history of recurrent upper abdominal pain. She was admitted to another hospital with a diagnosis of acute pancreatitis after she was found to have elevated serum amylase. On physical examination after admission a 5-7 cm mass was felt intermittently in the right upper quadrant. Liver function tests were normal and she was never jaundiced. Bile flow scan and ultrasound demonstrated a type I choledochal cyst. The cyst was successfully treated by excision with Roux en Y choledocho jejunostomy. The amylase content in the bile of the choledochal cyst was 4,730 somogyi units. She was discharged home eight days after the surgical procedure and in follow up two yr after the operation she is doing very well and has not had recurrence of the pain. Case 3 D.R., a 7 yr old North American Indian girl, presented with 18 mo history of intermittent episodes of anorexia, epigastric abdominal pain and vomiting. She was admitted to the hospital on several occasions; initially she was treated for Salmonelosis; subsequently she developed mild jaundice with bilirubin of 4.1 and normal SGOT and alkaline phosphatase; serum amylase was not done. From the Children's Hospital of Eastern Ontario Ottawa, Canada, and The Hospital for Sick Children Toronto, Canada. Presented at the 13th Annual Meeting of the Canadian Association of Paediatric Surgeons, Toronto, September 15, 1981. Address reprint requests to Gustavo Stringel, M.D., Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, Ontario. CANADA. K I H 8LI. 9 1982 by Grune & Stratton, Inc. 0022-3468/82/1704~005501.00/0
359
360
STRINGEL A N D FILLER
Case Summary 15 Yr Old Female
9 Yr Old Female
7 Yr Old Female
Episodic abdominal pain-duration
3 mo
6 yr
18 mo
Vomiting
Occasional
Yes
Yes
Jaundice Palpable mass
Nil Late RUQ not constant
Nil Nil
4.1 BIL Late Nil
Serum amylase (N = 7 0 - 3 0 0 IU)
> 1,000
Amylase content in choledocal cyst (IU per litre)
4,700
The diagnosis of chronic hepatitis was entertained. However, liver biopsy was normal. During the third admission following an episode of abdominal pain serum amylase was found to be markedly elevated with values up to 7400 IU per liter (N = 70-300) and urinary amylase of 6160 IU per liter (N - 100-2000). The diagnosis of acute pancreatitis was made. Ultrasound of the abdomen suggested the diagnosis of choledochal cyst. This was confirmed by HIDA bile flow scan and combined intravenous cholangiogram with computerized tomography of the biliary system (CAT Scan). A type I choledochal cyst was successfully treated by cyst excision and Roux en Y choledocho-jejunostomy.The amylase content of bile from the cyst was 121,000 IU; cultures were negative. Pathology showed choledochal cyst with acute inflamatory infiltrate and ulceration. She was discharged home 2 wk after surgical intervention. She has been completely asymptomatic 6 mo after discharge. DISCUSSION
Type l choledochal cyst presenting as acute pancreatitis has been described in the literature on three separate occasions. Andrews ~ described a 44 yr old woman with m a n y years of upper abdominal pain who was diagnosed as having cholecystitis and pancreatitis when a markedly elevated serum amylase was eventually noted. At laparotomy, a type I choledochal cyst was found. She has been well following partial excision of the cyst, cholecystectomy, sphincterotomy and Cattell tube drainage of the c o m m o n bile duct. Cuschieri ~~noted a 27 yr old pregnant woman who presented with severe abdominal pain and elevated serum amylase. S y m p t o m s subsided with conservative management. She had a laparotomy five yr before for suspected acute appendicitis but the operative diagnosis was pancreatitis. In the puerperium, a mass was felt in the upper abdomen. With a preoperative diagnosis of pancreatic pseudocyst, laparotomy was performed and she was found to have a type I choledochal cyst. This was treated by choledoc h o - c y s t o d u o d e n o s t o m y . T h e p a n c r e a s was thought to be inflamed. She recovered well except for one bout of cholangitis. The third case 8
4,900
7,400
32,000
121,000
was a four yr old girl with recurrent epigastric pain for 21/2 yr associated with fever, nausea and vomiting. These episodes occurred approximately once a month. She was found to have an elevated serum amylase and a diagnosis of recurrent pancreatitis was made. During evaluation of the biliary tree, a choledochal cyst was diagnosed by IV cholangiogram. She was treated by choledocho-jejunostomy with satisfactory results. The pancreas was found to be normal at surgery and she had no recurrence of pain or hyperamylasemia during a one year follow up. O f the three cases reported in the literature, two had some evidence of pancreatic inflammation at the time of operation, l~ In the other case, the pancreas was found to be normal despite the elevated serum amylase. 8 In our three cases which were initially diagnosed as acute pancreatitis, there was no anatomic evidence of pancreatic inflammation at the time of surgery. The abnormal a n a t o m y of the pancreatic and c o m m o n bile ducts in patients with choledochal cyst probably explains the high serum amylase concentration in the absence of pancreatic inflammation. Babbit was the first to show that, in patients with choledochal cyst, the pancreatic duct joins the c o m m o n duct proximal to the joint where the bile duct is surrounded by a sphincter. 13-~4 These findings have been confirmed by others, t5 This abnormal anatomic relationship allows retrograde reflux of pancreatic juice into the proximal c o m m o n bile duct. The current theory of pathogenesis of choledochal cyst holds that the action of the pancreatic enzymes within the biliary tree leads to chronic cholangitis, destruction of the biliary tract mucosa, weakness of the bile duct wall, and eventually cystic dilatation. 13"14J5 Presumably, amylase, which has been shown to be present in high concentrations within the c y s t , 3'16'19 h a s ready access to the blood stream through the inflamed denuded wall of the bile duct cyst.
FICTITIOUS PANCREATITIS IN CHOLEDOCHAL CYST
361
It is important to recognize that the classical presentation of choledochal cyst often is not seen) 7 A high suspicion of this entity, especially in patients with elevated serum amylase, will lead to an early diagnosis before complications such as cholangitis, hepatic abscess, biliary cirrhosis and portal hypertension appear. 3'8 When suspected, the diagnosis can be confirmed by ultrasound, bile flow scan and cholangiography alone or combined with computerized tomography. Although choledochal cyst has been treated most often by choledochocyst-jejunostomy or choledochocystduodenostomy,3'~8 recent reports in the literature indicate that the current treatment of choice is cyst excision, cholecystectomy and Roux en Y choledocho-jejunostomy) 9 We have now treated ten patients successfully with
this technique. In addition to providing adequate drainage of bile, cyst excision interrupts the abnormal pathway which allows pancreatic reflux and thereby prevents inflammation of the biliary tree. It is difficult to decide whether a degree of pancreatitis is also present in patients with choledochal cyst and elevated serum amylase. However, our experience indicates that the presence of hyperamylasemia should not delay appropriate surgical management of the cyst. None of our ten patients with choledochal cyst treated by excision had recurrence of their symptoms. In the three who presented clinically with elevated serum amylase, no further suggestion of pancreatitis has been noted clinically or by laboratory study after excision of the choledochal cyst.
REFERENCES
1. Flanigan DP: Biliary cysts. Ann Surg 182:635-643, 1975 2. Vatero, A: Dissertation in Auguralis Medica Proes. Diss qua scirrhris viscerum disseret CS Exlerus 70:19, 1723 (University library, Edinburg) 3. Alonso-Lej F, Rever WB, Pessagno D J: Congenital choledochal cyst, with a report of 2 and an analysis of 94 cases: Internation Abstracts of Surgery. Surg Gynecol Obstet 108:1-30, 1959 4. Caroli J: Diseases of intrahepatic bile ducts. Israel J Med Sci 4:21, 1968 5. Tsuchida Y, Ishida M: Dilatation of the intrahepatic bile ducts in congenital cystic dilatation of the common bile duct. Surgery 69:776, 1971 6. Saito S, lshida M: Congenital choledochal cyst (cystic dilatation of common bile ducts). Prog Pediatr Surg 6:63-90, 1974 7. Archambault H, Archambault R, and Lasker, GW: Choledocus cyst a case treated by Roux type anastomosis of jejunum to the cyst. Ann Surg, 1950, 132:1144 8. Karjoo M, Bishop HC, Borns P, Holtzapple PG: Choledochal cyst presenting as recurrent pancreatitis. Pediatrics 51:289-291, 1973 9. Tagart RE: Perforation of a congenital cyst of the common bile duct. Br J Surg 44:18 21, 1956
10. Cuschieri A, Davies RS: Acute pancreatitis complicating a choledochal cyst. Br Med J, 3:698, 1969 11. Andrews CE, Ande WF: Choledochal cyst treated by sphincterotomy. Arch Surg 79:170-174 12. Valayer J, Alasille D: Experience with choledochal cyst. J Pediatr Surg 10:65-68, 1975 13. Babbit DP, Starshak R J, Clemett AR: Choledochal cyst: A concept of etiology. Am J Roentgenol 119:57-62, 1973 14. Babbitt DP: Congenital choledochal cyst: New etiological concept based on anomalous relationships of common bile duct and pancreatic bulb. Ann Radio 12:231, 1969 15. Miyano T, Suruga K, Suda K: Abnormal choledochopancreatico junction related to the etiology of infantile obstructive jaundice diseases. J Pediatr Surg 14:16-26, 1979 16. Kimura K, Tsugawa C, Ogawa K, Matsumoto Y, Yamamoto T, Kubo M, Asada S, Nishiyama S, Ito H: Choledochal cyst. Arch Surg 113:159-163, 1978 17. Lilly JR and Altman RP: The biliary tree, in Ravitch MM, Welch K J, Benson CD, Aberdeen E, Randolph JG: Pediatric Surgery (Chapter 81). Year book Medical Publishers Inc., 1979, Third ed, p 833 834 18. Fonkalsrud EW, Boles ET: Choledochal cysts in infancy and childhood. Surg Gynecol Obstet 121:733, 1965 19. Filler RM, Stringel G: Treatment of choledochal cyst by excision. J Pediatr Surg 15:437-442, 1980
INDEX WORDS: Pancreatitis; choledochal cyst.
Y S T I C D I L A T A T I O N o f t h e b i l i a r y d u c t is r a r e a n d f a s c i n a t i n g e n t i t y w i t h 955 c a s e s r e p o r t e d in t h e w o r l d l i t e r a t u r e u p to 1975.1 T h e first d e s c r i p t i o n o f c h o l e d o c h a l cyst is a t t r i b u t e d to V a t e r in 1723; 2 in 1959 A l o n s o - L e j p u b l i s h e d an e x c e l l e n t r e v i e w o f c a s e s w i t h a s i m p l e c l a s s i f i c a t i o n ? H i s classification i n c l u d e d t h r e e t y p e s of cyst, all e x t r a h e p a t i c : T y p e I, t h e m o s t c o m m o n f o r m , also c a l l e d c o n g e n i t a l c y s t i c d i l a t a t i o n of t h e c o m m o n bile d u c t ; t y p e II or c o n g e n i t a l d i v e r t i c u l u m of t h e c o m m o n bile d u c t ; type III, congenital choledochocele. Subsequently other types of multiple and intrahepatic c y s t i c d i l a t a t i o n s h a v e b e e n a d d e d to A l o n s o L e j ' s o r i g i n a l c l a s s i f i c a t i o n 4'5'6 T h e classic p r e s e n t a t i o n of c h o l e d o c h a l cyst has b e e n r e g a r d e d as a t r i a d o f r i g h t u p p e r q u a d r a n t a b d o m i n a l pain, j a u n d i c e a n d a p a l p a ble a b d o m i n a l m a s s ; a b d o m i n a l p a i n b e i n g t h e m o s t f r e q u e n t finding. 3"7'8O t h e r u n u s u a l t y p e s o f presentation reported with increasing frequency include: r u p t u r e of t h e c h o l e d o c h a l cyst w i t h b i l e peritonitis, 9 p a n c r e a t i t i s , a n d s'l~ b l e e d i n g esop h a g e a l v a r i c e s d u e to b i l i a r y cirrhosis.
C
Journal of Pediatric Surgery, Vol. 17, No. 4 (August), 1982
CASE REPORTS
Case I LT., a 9 year old Japanese girl, had recurrent bouts of severe epigastric pain and vomiting since she was 3 yr old. She was admitted to another hospital on several occasions and found to have elevated serum amylase and she was treated as having acute pancreatitis. She was never jaundiced and liver function tests were normal; there was no palpable mass on physical examination. Type I choledochal cyst w a s diagnosed by intravenous cholangiogram which was obtained to see if the patient had gallstones. The cyst was successfully treated by excision and Roux en u choledocho-jejunost0my. The amylase content of the bile in the choledochal cyst was found to be over 32,000 somogyi units. She did very well after the procedure and was discharged home 18 days after the operation and in follow up after three years she was doing very well with no recurrence of the abdominal pain. Case 2 B.M., a 15 year old Caucasian girl, presented with a 3 mo history of recurrent upper abdominal pain. She was admitted to another hospital with a diagnosis of acute pancreatitis after she was found to have elevated serum amylase. On physical examination after admission a 5-7 cm mass was felt intermittently in the right upper quadrant. Liver function tests were normal and she was never jaundiced. Bile flow scan and ultrasound demonstrated a type I choledochal cyst. The cyst was successfully treated by excision with Roux en Y choledocho jejunostomy. The amylase content in the bile of the choledochal cyst was 4,730 somogyi units. She was discharged home eight days after the surgical procedure and in follow up two yr after the operation she is doing very well and has not had recurrence of the pain. Case 3 D.R., a 7 yr old North American Indian girl, presented with 18 mo history of intermittent episodes of anorexia, epigastric abdominal pain and vomiting. She was admitted to the hospital on several occasions; initially she was treated for Salmonelosis; subsequently she developed mild jaundice with bilirubin of 4.1 and normal SGOT and alkaline phosphatase; serum amylase was not done. From the Children's Hospital of Eastern Ontario Ottawa, Canada, and The Hospital for Sick Children Toronto, Canada. Presented at the 13th Annual Meeting of the Canadian Association of Paediatric Surgeons, Toronto, September 15, 1981. Address reprint requests to Gustavo Stringel, M.D., Children's Hospital of Eastern Ontario, 401 Smyth Road, Ottawa, Ontario. CANADA. K I H 8LI. 9 1982 by Grune & Stratton, Inc. 0022-3468/82/1704~005501.00/0
359
360
STRINGEL A N D FILLER
Case Summary 15 Yr Old Female
9 Yr Old Female
7 Yr Old Female
Episodic abdominal pain-duration
3 mo
6 yr
18 mo
Vomiting
Occasional
Yes
Yes
Jaundice Palpable mass
Nil Late RUQ not constant
Nil Nil
4.1 BIL Late Nil
Serum amylase (N = 7 0 - 3 0 0 IU)
> 1,000
Amylase content in choledocal cyst (IU per litre)
4,700
The diagnosis of chronic hepatitis was entertained. However, liver biopsy was normal. During the third admission following an episode of abdominal pain serum amylase was found to be markedly elevated with values up to 7400 IU per liter (N = 70-300) and urinary amylase of 6160 IU per liter (N - 100-2000). The diagnosis of acute pancreatitis was made. Ultrasound of the abdomen suggested the diagnosis of choledochal cyst. This was confirmed by HIDA bile flow scan and combined intravenous cholangiogram with computerized tomography of the biliary system (CAT Scan). A type I choledochal cyst was successfully treated by cyst excision and Roux en Y choledocho-jejunostomy.The amylase content of bile from the cyst was 121,000 IU; cultures were negative. Pathology showed choledochal cyst with acute inflamatory infiltrate and ulceration. She was discharged home 2 wk after surgical intervention. She has been completely asymptomatic 6 mo after discharge. DISCUSSION
Type l choledochal cyst presenting as acute pancreatitis has been described in the literature on three separate occasions. Andrews ~ described a 44 yr old woman with m a n y years of upper abdominal pain who was diagnosed as having cholecystitis and pancreatitis when a markedly elevated serum amylase was eventually noted. At laparotomy, a type I choledochal cyst was found. She has been well following partial excision of the cyst, cholecystectomy, sphincterotomy and Cattell tube drainage of the c o m m o n bile duct. Cuschieri ~~noted a 27 yr old pregnant woman who presented with severe abdominal pain and elevated serum amylase. S y m p t o m s subsided with conservative management. She had a laparotomy five yr before for suspected acute appendicitis but the operative diagnosis was pancreatitis. In the puerperium, a mass was felt in the upper abdomen. With a preoperative diagnosis of pancreatic pseudocyst, laparotomy was performed and she was found to have a type I choledochal cyst. This was treated by choledoc h o - c y s t o d u o d e n o s t o m y . T h e p a n c r e a s was thought to be inflamed. She recovered well except for one bout of cholangitis. The third case 8
4,900
7,400
32,000
121,000
was a four yr old girl with recurrent epigastric pain for 21/2 yr associated with fever, nausea and vomiting. These episodes occurred approximately once a month. She was found to have an elevated serum amylase and a diagnosis of recurrent pancreatitis was made. During evaluation of the biliary tree, a choledochal cyst was diagnosed by IV cholangiogram. She was treated by choledocho-jejunostomy with satisfactory results. The pancreas was found to be normal at surgery and she had no recurrence of pain or hyperamylasemia during a one year follow up. O f the three cases reported in the literature, two had some evidence of pancreatic inflammation at the time of operation, l~ In the other case, the pancreas was found to be normal despite the elevated serum amylase. 8 In our three cases which were initially diagnosed as acute pancreatitis, there was no anatomic evidence of pancreatic inflammation at the time of surgery. The abnormal a n a t o m y of the pancreatic and c o m m o n bile ducts in patients with choledochal cyst probably explains the high serum amylase concentration in the absence of pancreatic inflammation. Babbit was the first to show that, in patients with choledochal cyst, the pancreatic duct joins the c o m m o n duct proximal to the joint where the bile duct is surrounded by a sphincter. 13-~4 These findings have been confirmed by others, t5 This abnormal anatomic relationship allows retrograde reflux of pancreatic juice into the proximal c o m m o n bile duct. The current theory of pathogenesis of choledochal cyst holds that the action of the pancreatic enzymes within the biliary tree leads to chronic cholangitis, destruction of the biliary tract mucosa, weakness of the bile duct wall, and eventually cystic dilatation. 13"14J5 Presumably, amylase, which has been shown to be present in high concentrations within the c y s t , 3'16'19 h a s ready access to the blood stream through the inflamed denuded wall of the bile duct cyst.
FICTITIOUS PANCREATITIS IN CHOLEDOCHAL CYST
361
It is important to recognize that the classical presentation of choledochal cyst often is not seen) 7 A high suspicion of this entity, especially in patients with elevated serum amylase, will lead to an early diagnosis before complications such as cholangitis, hepatic abscess, biliary cirrhosis and portal hypertension appear. 3'8 When suspected, the diagnosis can be confirmed by ultrasound, bile flow scan and cholangiography alone or combined with computerized tomography. Although choledochal cyst has been treated most often by choledochocyst-jejunostomy or choledochocystduodenostomy,3'~8 recent reports in the literature indicate that the current treatment of choice is cyst excision, cholecystectomy and Roux en Y choledocho-jejunostomy) 9 We have now treated ten patients successfully with
this technique. In addition to providing adequate drainage of bile, cyst excision interrupts the abnormal pathway which allows pancreatic reflux and thereby prevents inflammation of the biliary tree. It is difficult to decide whether a degree of pancreatitis is also present in patients with choledochal cyst and elevated serum amylase. However, our experience indicates that the presence of hyperamylasemia should not delay appropriate surgical management of the cyst. None of our ten patients with choledochal cyst treated by excision had recurrence of their symptoms. In the three who presented clinically with elevated serum amylase, no further suggestion of pancreatitis has been noted clinically or by laboratory study after excision of the choledochal cyst.
REFERENCES
1. Flanigan DP: Biliary cysts. Ann Surg 182:635-643, 1975 2. Vatero, A: Dissertation in Auguralis Medica Proes. Diss qua scirrhris viscerum disseret CS Exlerus 70:19, 1723 (University library, Edinburg) 3. Alonso-Lej F, Rever WB, Pessagno D J: Congenital choledochal cyst, with a report of 2 and an analysis of 94 cases: Internation Abstracts of Surgery. Surg Gynecol Obstet 108:1-30, 1959 4. Caroli J: Diseases of intrahepatic bile ducts. Israel J Med Sci 4:21, 1968 5. Tsuchida Y, Ishida M: Dilatation of the intrahepatic bile ducts in congenital cystic dilatation of the common bile duct. Surgery 69:776, 1971 6. Saito S, lshida M: Congenital choledochal cyst (cystic dilatation of common bile ducts). Prog Pediatr Surg 6:63-90, 1974 7. Archambault H, Archambault R, and Lasker, GW: Choledocus cyst a case treated by Roux type anastomosis of jejunum to the cyst. Ann Surg, 1950, 132:1144 8. Karjoo M, Bishop HC, Borns P, Holtzapple PG: Choledochal cyst presenting as recurrent pancreatitis. Pediatrics 51:289-291, 1973 9. Tagart RE: Perforation of a congenital cyst of the common bile duct. Br J Surg 44:18 21, 1956
10. Cuschieri A, Davies RS: Acute pancreatitis complicating a choledochal cyst. Br Med J, 3:698, 1969 11. Andrews CE, Ande WF: Choledochal cyst treated by sphincterotomy. Arch Surg 79:170-174 12. Valayer J, Alasille D: Experience with choledochal cyst. J Pediatr Surg 10:65-68, 1975 13. Babbit DP, Starshak R J, Clemett AR: Choledochal cyst: A concept of etiology. Am J Roentgenol 119:57-62, 1973 14. Babbitt DP: Congenital choledochal cyst: New etiological concept based on anomalous relationships of common bile duct and pancreatic bulb. Ann Radio 12:231, 1969 15. Miyano T, Suruga K, Suda K: Abnormal choledochopancreatico junction related to the etiology of infantile obstructive jaundice diseases. J Pediatr Surg 14:16-26, 1979 16. Kimura K, Tsugawa C, Ogawa K, Matsumoto Y, Yamamoto T, Kubo M, Asada S, Nishiyama S, Ito H: Choledochal cyst. Arch Surg 113:159-163, 1978 17. Lilly JR and Altman RP: The biliary tree, in Ravitch MM, Welch K J, Benson CD, Aberdeen E, Randolph JG: Pediatric Surgery (Chapter 81). Year book Medical Publishers Inc., 1979, Third ed, p 833 834 18. Fonkalsrud EW, Boles ET: Choledochal cysts in infancy and childhood. Surg Gynecol Obstet 121:733, 1965 19. Filler RM, Stringel G: Treatment of choledochal cyst by excision. J Pediatr Surg 15:437-442, 1980