Preliminary exploration of animal models of congenital choledochal cysts

BACKGROUND Various animal models have been used to explore the pathogenesis of choledochal cysts(CCs),but with little convincing results.Current surgical techniques can achieve satisfactory outcomes for treatment of CCs.Consequently,recent studies have focused more on clinical issues rather than basic research.Therefore,we need appropriate animal models to further basic research.AIM To establish an appropriate animal model that may contribute to the investigation of the pathogenesis of CCs.METHODS Eighty-four specific pathogen-free female Sprague-Dawley rats were randomly allocated to a surgical group,sham surgical group,or control group.A rat model of CC was established by partial ligation of the bile duct.The reliability of the model was confirmed by measurements of serum biochemical indices,morpho-logy of common bile ducts of the rats as well as molecular biology experiments in rat and human tissues.RESULTS Dilation classified as mild(diameter,≥1 mm to<3 mm),moderate(≥3 mm to<10 mm),and severe(≥10 mm)was observed in 17,17,and 2 rats in the surgical group,respectively,while no dilation was observed in the control and sham surgical groups.Serum levels of alanine aminotransferase,aspartate aminotrans-ferase,total bilirubin,direct bilirubin,and total bile acids were significantly elevated in the surgical group as compared to the control group 7 d after surgery,while direct bilirubin,total bilirubin,and gamma-glutamyltransferase were further increased 14 d after surgery.Most of the biochemical indices gradually decreased to normal ranges 28 d after surgery.The protein expression trend of signal transducer and activator of transcription 3 in rat model was consistent with the human CC tissues.CONCLUSION The model of partial ligation of the bile duct of juvenile rats could morphologically simulate the cystic or fusiform CC,which may contribute to investigating the pathogenesis of CC.

Maternal choledochal cysts in pregnancy:A systematic review of case reports and case series

BACKGROUND Choledochal cysts(CC)are cystic dilatations of the biliary tract,usually diagnosed during childhood,with an estimated incidence in the general population of 1:100000.Complications related to CC include rupture,biliary obstruction,and cholangitis.Maternal CC in pregnancy are rarely reported,and there are no guidelines on optimal management.AIM To systematically review maternal CC diagnosed during pregnancy or postpartum with regard to the clinical presentation of CC,the mode of treatment and delivery,and maternal outcomes.METHODS A literature search of cases and case series of maternal CC in pregnancy and postpartum was conducted using MEDLINE/PubMed,Web of Science,Google Scholar,and Embase.There were no restrictions on language or publication year.Databases were lastly accessed on September 1,2022.RESULTS Overall,71 publications met the inclusion criteria,reporting 97 cases.Eighty-eight cases were diagnosed during pregnancy and nine in the puerperium.The most common symptoms were abdominal pain(81.2%)and jaundice(60.4%).Interventions for CC complications were required in 52.5%of the cases,and 34%of pregnancies were induced.Urgent cesarean section(CS)was done in 24.7%.The maternal mortality was 7.2%,while fetal mortality was inconsistently reported.Cholangitis,CC>15 cm,and bilirubin levels>80 mmol/L were associated with a higher likelihood of urgent CS and surgical intervention for CC.Bilirubin levels positively correlated with CC size.There was no correlation between age and cyst dimension,gestational age at cyst discovery,and CC size.CONCLUSION Although rare,maternal CC in pregnancy should be included in the evaluation of jaundice with upper abdominal pain.Symptomatology and clinical course are variable,and treatment may range from an expectative approach to emergent surgical CC treatment and urgent CS.While most cases were managed by conservative measures or drainage procedures,CC>15 cm and progressive cholangitis carry the risk of CC rupture and septic complications,which may increase the rates of unfavorable maternal and fetal outcomes.Therefore,such cases require specific surgical and obstetric interventions.

Role of magnetic resonance cholangiopancreatography in diagnosing choledochal cysts: Case series and review

AIM:To determine the merits of magnetic resonance cholangiopancreatography(MRCP) as the primary diagnostic test for choledochal cysts(CC’s).METHODS:Between 2009 and 2012,patients who underwent MRCP for perioperative diagnosis were identified.Demographic information,clinical characteristics,and radiographic findings were recorded.MRCP results were compared with intraoperative findings.A PubMed search identified studies published between 1996-2012,employing MRCP as the primary preoperative imaging and comparing results with either endoscopic retrograde cholangiopancreatography(ERCP) or operative findings.Detection rates for CC’s and abnormal pancreaticobiliary junction(APBJ) were calculated.In addition detection rates for clinically related biliary pathology like choledocholithiasis and cholangiocarcinomas in patients diagnosed with CC’s were also evaluated.RESULTS:Eight patients were identified with CC’s.Six patients out of them had typeⅣCC’s,1 had type I and 1 had a new variant of choledochal cyst with confluent dilatation of the common bile duct(CBD) and cystic duct.Seven patients had an APBJ and 3 of those had a long common-channel.Gallstones were found in 2 patients,1 had a CBD stone,and 1 pancreatic-duct stone was also detected.In all cases,MRCP successfully identified the type of CC’s,as well as APBJ with ductal stones.From analyzing the literature,we found that MRCP has 96%-100% detection rate for CC’s.Additionally,we found that the range for sensitivity,specificity,and diagnostic accuracy was 53%-100%,90%-100% and 56%-100% in diagnosing APBJ.MRCP’s detection rate was 100% for choledocholithiasis and 87% for cholangiocarcinomas with concurrent CC’s.CONCLUSION:After initial ultrasound and computed tomography scan,MRCP should be the next diagnostic test in both adult and pediatric patients.ERCP should be reserved for patients where therapeutic intervention is needed.

Robotic-assisted surgery for pediatric choledochal cyst: Case report and literature review

Our paper describes the key surgical points of pediatric choledochocystectomy performed completely by Da Vinci robotic system. A choledochocystectomy was safely carried out for a girl at our hospital, and without any complication. Then systematic literature review was done to discuss the methods of intestine surgery and intestinal anastomosis, the use of 3 rd robotic arm, the surgical safety and advantages comparing open and laparoscopic surgery. We systematically reviewed choledochocystectomy for children performed by robotic surgery. We included a total of eight domestic and foreign reports and included a total of 86 patients, whose average age was 6.3(0.3-15.9) years; the maleto-female ratio was 1:3.5(19:67). Seven patients experienced conversion to open surgery, and the surgery success rate was 91.9%(79/86). The average total operation time was 426(180-520) min, the operation time on the machine was 302(120-418) min, 11 cases used the number 3 arm, and the remaining mainly used the hitch-stitch technique to suspend the stomach wall and liver. Forty-seven patients underwent pull-through intestine and intestinal anastomosis, and 39 patients underwent complete robotic intestine surgery and intestinal anastomosis. The hospitalization time of roboticassisted choledochocystectomy was 8.8 d. Eight patientshad biliary fistula and were all cured by conservative treatment and continuous observation. One patient had anastomotic stenosis, and one patient had wound dehiscence, both cured by surgery. Choledochocystectomy for children performed by completely robotic surgery and Roux-en-Y hepaticojejunostomy is safe and feasible. The initial experience shows that this surgical approach has a clearer field than the traditional endoscopy, and its operation is more flexible, the surgery is more accurate, and the injury is smaller. With the advancement of technology and the accumulation of surgeons' experience, robotic surgery may become a new trend in this surgical procedure.

Narrow portion of the terminal choledochus is a cause of upstream biliary dilatation in patients with anomalous union of the pancreatic and biliary ducts

AIM: To clarify the pathogenesis of biliary dilatation associated with anomalous union of the pancreatic and biliary ducts (AUPBD).METHODS: Direct cholangiopancreatograms of 350 adult patients with or with suspicion of hepatobiliary or pancreatic disorders were reviewed. AUPBD was diagnosed cholangiopancreatographically, when the pancreaticobiliary ductal union was located above the narrow distal segment of the bile duct, which represents the action of the sphincter of Oddi. The narrow portion of the terminal choledochus was defined as symmetrical stricture of the common bile duct just above the pancreaticobiliary ductal union.RESULTS: AUPBD was found in 36 patients. Among cholangiopancreatographic features, the narrow portion of the terminal choledochus was the most pathognomonic for AUPBD (accuracy, 98%); it was present in 29 (81%)patients with AUPBD, but was not found in any patients without AUPBD. Among patients with AUPBD, biliary dilatation (＞10 mm) was more frequent in those with the narrow portion of the terminal choledochus (23/29)than in those without (2/7; P = 0.018) AUPBD. Among the patients with both AUPBD and the narrow portion of the terminal choledochus, there was a strong negative correlation between the minimum diameter of the narrow portion and the maximum diameter of the choledochus (r = -0.78, P＜0.001), suggesting that the degree of biliary narrowing at the narrow portion correlates with that of upstream biliary dilatation.CONCLUSION: The narrow portion of the terminal choledochus, a pathognomonic radiologic feature of AUPBD, may be a cause of biliary dilatation in patients with AUPBD.

Open surgical treatment of choledochocele: A case report and review of literature

Choledochocele （also known as type？Ⅲ？ choledochal cyst according to Todani’s classifcation） is a cystic dilation of the distal segment of the common bile duct protru-ding into the duodenal lumen. Cases are rare and the etiology remains unclear. It is usually misdiagnosed as peptic ulcer, as in the patient whose case is described here. Multislice spiral computed tomography and magnetic resonance cholangiopancreatography may be comparable to endoscopic retrograde cholangiogra-phy for diagnosis of choledochocele. Both endoscopic therapy and open surgical management are safe options, and size of the cyst plays a role in the decision-making for which approach to apply. A 50-year-old woman admitted to our hospital with upper abdominal pain caused by choledochocele with large size was successfully treated by open surgical management. We present the details of her case in this case report and discuss the recent literature on such cases and their therapeutic management.

Diagnosis and treatment of congenital choledochal cyst: 20 years' experience in China

AIM: To summarize the experience of diagnosis and treatment of congenital choledochal cyst in the past 20 years (1980-2000). METHODS: The clinical data of 108 patients admitted from 1980 to 2000 were analyzed retrospectively. RESULTS: Abdominal pain,jaundice and abdominal mass were presented in most child cases. Clinical symptoms in adult cases were non-specific, resulting in delayed diagnosis frequently. Fifty-seven patients (52.7%) had coexistent pancreatiobiliary disease. Carcinoma of the biliary duct occurred in 18 patients (16.6%).Ultrasonic examination was undertaken in 94 cases, ERCP performed in 46 cases and CT in 71 cases. All of the cases were correctly diagnosed before operation. Abnormal pancreatobiliary duct junction was found in 39 patients. Before 1985 the diagnosis and classification of congenital choledochal cyst were established by ultrasonography preoperatively and confirmed during operation, the main procedures were internal drainage by cyst enterostomy. After 1985, the diagnosis was established by ERCP and CT, and cystectomy with Roux-en-Y hepaticojejunostomy was the conventional procedures.In 1994, we reported a new and simplified operative procedure in order to reduce the risk of choledochal cyst malignancy. Postoperative complication was mainly retrograde infection of biliary tract, which could be controlled by the administration of antibiotics, there was no perioperative mortality. CONCLUSION: The concept in diagnosis and treatment of congenital choledochal cyst has obviously been changed greatly.CT and ERCP were of great help in the classification of the disease.Currently, cystectomy with Roux-en-Y hepaticojejunostomy is strongly recommended as the choice for patients with type I and type IV cysts. Piggyback orthotopic liver transplantation is indicated in type V cysts (Caroli's disease) with frequently recurrent cholangitis.

Choledochal cysts: Similarities and differences between Asian and Western countries

Choledochal cysts(CCs)are rare bile duct dilatations,intra-and/or extrahepatic,and have higher prevalence in the Asian population compared to Western populations.Most of the current literature on CC disease originates from Asia where these entities are most prevalent.They are thought to arise from an anomalous pancreaticobiliary junction,which are congenital anomalies between pancreatic and bile ducts.Some similarities in presentation between Eastern and Western patients exist such as female predominance,however,contemporary studies suggest that Asian patients may be more symptomatic on presentation.Even though CC disease presents with an increased malignant risk reported to be more than 10%after the second decade of life in Asian patients,this risk may be overstated in Western populations.Despite this difference in cancer risk,management guidelines for all patients with CC are based predominantly on observations reported from Asia where it is recommended that all CCs should be excised out of concern for the presence or development of biliary tract cancer.

Diagnosis and management of choledochal cyst: 20 years of single center experience

We report the first case series from Africa and the Middle East on choledochal cyst, a disease which shows significant geographical distribution with high incidence in the Asian population. In this study, the epidemiological data of the patients are presented and analyzed. Attention was paid to diagnostic imaging and its accuracy in the diagnosis and classification of choledochal cyst. Most cases of choledochal cyst disease have type&#x02005;I&#x02005;and IV-A cysts according to the Todani classification system, which support the etiological theories of choledochal cyst, especially Babbitt&#x02019;s theory of the anomalous pancreaticobiliary duct junction, which are clearly stated. The difficulties and hazards of surgical management and methods used to avoid operative complications are clarified. Early and late postoperative complications are also included. This study should be followed by multicenter studies throughout Egypt to help assess the incidence of choledochal cysts in one of the largest populations in Africa and the Middle East.

Coagulopathy in a subtype of choledochal cyst and management strategy

AIM: To evaluated our management algorithm of the coagulopathy. We evaluated our management algorithm of the coagulopathy.

Early complications after excision with hepaticoenterostomy for infants and children with choledochal cysts

Objective: To retrospectively study the early compli- cations of excision with hepaticoenterostomy for in- fants and children with choledochal cysts. Methods: We analyzed 16 patients with early posto- perative complications out of 173 patients with con- genital choledochal cysts aged 27 days to 14 years (mean 2.4 years) who had undergone excisional pro- cedures and biliary tract reconstruction. Results: The early complications included bile leak- age (10 patients), abdominal wall dehiscence (3), and hepatic failure, pancreatic juice leakage and postoperative intussusception (each in 1) respective- ly. Three patients died from bile leakage and 1 from postoperative hepatic failure. No statistical differen- ces were observed between the procedures of biliary tract reconstruction with jejunal segment interposi- tion hepaticoduodenostomy and Roux-en-Y hepatico- jejunostomy (P>0.75). The morbidity was signifi- cantly higher in infants below 1 year than in children (P<0.005). Prevention and treatment of the com- plications were discussed. Conclusion: Bile leakage and abdominal wall dehis- cence are major early postoperative complications. The morbidity of cholechal cysts is higher in infants than in children. Exploratory laparotomy should not be delayed when biliary leakage with diffuse peritoni- tis appears. The 'tension suture in the fascial space of the abdominal wall' is useful to prevent and treat wound dehiscence.

Outcomes of laparoscopic bile duct exploration for choledocholithiasis with small common bile duct

BACKGROUND Laparoscopic cholecystectomy(LC)combined with laparoscopic common bile duct(CBD)exploration(LCBDE)is one of the main treatments for choledocholithiasis with CBD diameter of larger than 10 mm.However,for patients with small CBD(CBD diameter≤8 mm),endoscopic sphincterotomy remains the preferred treatment at present,but it also has some drawbacks associated with a series of complications,such as pancreatitis,hemorrhage,cholangitis,and duodenal perforation.To date,few studies have been reported that support the feasibility and safety of LCBDE for choledocholithiasis with small CBD.AIM To investigate the feasibility and safety of LCBDE for choledocholithiasis with small CBD.METHODS A total of 257 patients without acute cholangitis who underwent LC+LCBDE for cholecystolithiasis from January 2013 to December 2018 in one institution were reviewed.The clinical data were retrospectively collected and analyzed.According to whether the diameter of CBD was larger than 8 mm,257 patients were divided into large CBD group(n=146)and small CBD group(n=111).Propensity score matching(1:1)was performed to adjust for clinical differences.The demographics,intraoperative data,short-term outcomes,and long-term follow-up outcomes for the patients were recorded and compared.RESULTS In total,257 patients who underwent successful LC+LCBDE were enrolled in the study,146 had large CBD and 111 had small CBD.The median follow-up period was 39(14-86)mo.For small CBD patients,the median CBD diameter was 0.6 cm(0.2-2.0 cm),the mean operating time was 107.2±28.3 min,and the postoperative bile leak rate,rate of residual CBD stones(CBDS),CBDS recurrence rate,and CBD stenosis rate were 5.41%(6/111),3.60%(4/111),1.80%(2/111),and 0%(0/111),respectively;the mean postoperative hospital stay was 7.4±3.6 d.For large CBD patients,the median common bile duct diameter was 1.0 cm(0.3-3.0 cm),the mean operating time was 115.7±32.0 min,and the postoperative bile leak rate,rate of residual CBDS,CBDS recurrence rate,and CBD stenosis rate were 5.41%(9/146),1.37%(2/146),6.85%(10/146),and 0%(0/146),respectively;the mean postoperative hospital stay was 7.7±2.7 d.After propensity score matching,184 patients remained,and all preoperative covariates except diameter of CBD stones were balanced.Postoperative bile leak occurred in 11 patients overall(5.98%),and no difference was found between the small CBD group(4.35%,4/92)and the large CBD group(7.61%,7/92).The incidence of CBDS recurrence did not differ significantly between the small CBD group(2.17%,2/92)and the large CBD group(6.52%,6/92).CONCLUSION LC+LCBDE is safe and feasible for choledocholithiasis patients with small CBD and did not increase the postoperative bile leak rate compared with choledocholithiasis patients with large CBD.

Amylase level in extra hepatic bile duct in adult patients with choledochal cyst plus anomalous pancreatico-biliary ductal union

AIM: To investigate the relationship between pancreatic amylase in bile duct and the clinico-pathological features in adult patients with choledochal cyst and anomalous pancreatico-biliary ductal union (APBDU).METHODS: From 39 patients who underwent surgery for choledochal cyst between March 1995 and March 2003,we selected 15 adult patients who had some symptoms and were radiologically diagnosed as APBDU, and their clinico-pathological features were subsequently evaluated retrospectively. However, we could not obtain biliary amylase in all the patients because of the surgeon's slip.Therefore, we measured the amylase level in gall bladder of 10 patients and in common bile duct of 11 patients.RESULTS: Levels of amylase in common bile duct and gall bladder ranged from 11 500 to 212 000 IU/L, and the younger the patients, the higher the biliary amylase level (r= -0.982, P＜0.01). Pathologically, significant correlation was found between the size of choledochal cyst and the grade of inflammation (r= 0.798,P＜0.01). And, significant correlation was found between the level of amylase in gall bladder and the grade of hyperplasia. On the other hand, there was no correlation to the age of symptomatic onset or inflammatory grade (r = 0.743, P＜0.05). Level of lipase was elevated from 6 000 to 159 000 IU/L in bile duct and from 14 400 to 117 000 IU/L in the gall bladder;however, there was no significant correlation with age or clinico-pathological features.CONCLUSION: The results support the notion that amylase has a particular role in the onset of symptoms, and suggest that a large amount of biliary amylase induces early onset of symptom, thereby making early diagnosis possible.

Procedures for congenital choledochal cysts and curative effect analysis in adults

Objective: To evaluate the procedures and timing of operation as well as long-term postoperative effect of congenital choledochal cysts (CCC) in adults. Methods: The procedures and timing of operation, effective rate, re-operation rate and incidence of car- cinoma after operation for 70 adult patients with CCC from January 1980 to June 1999 were analyzed retrospectively. Results: The re-operation rate of external drainage was 86% (6/7). The effective rate of internal drain- age was significantly lower than that of cyst resection (3/10 vs 45/49, X^2=20. 94, P<0.001). The re-op- eration rate and incidence of carcinoma of internal drainage were higher than those of cyst resection (5/ 10 vs 3/49, X^2=13. 64, P<0. 001 and 3/10 vs 3/49, X^2=5. 18, P<0. 025). The reoperation rate of e- mergency surgery was higher than that of selective operation (8/10 vs 6/56, X^2=24. 37, P<0.001). Conclusions: External drainage should be the first- aid measure and the therapy of choice on emergency basis. Internal drainage should never be attempted. Cyst resection with Roux-en-Y hepaticojejunostomy is recommended as the treatment of choice in selective operation.

Choledochal cyst with large stone cast and portal hypertension

BACKGROUND:Choledochal cysts in adults are more commonly associated with complications such as cystolithiasis,recurrent cholangitis,portal hypertension and malignancy,than in the pediatric age group.METHOD:We report a case of adult choledochal cyst with long-term complication of large stone cast and portal hypertension due to secondary biliary cirrhosis.RESULTS:A 50-year-old patient presented with obstructive jaundice and hepatosplenomegaly.On investigation,she was diagnosed as having a choledochal cyst with large stone cast and portal hypertension.Single stage resection of the choledochal cyst with Roux-en-Y hepaticojejunostomy was done by meticulous dissection and ligation of collaterals.CONCLUSION:Single stage resection of a choledochal cyst is possible in spite of associated portal hypertension,if the portal vein is patent.

Expressions of p53 and inducible nitric oxid synthase in congenital choledochal cysts

BACKGROUND: Choledochal cyst, an isolated defect un- restricted to the bile duct, is more appropriately regarded as the sentinel feature of a constellation of anomalies affect- ing the pancreatobiliary system. This study was to assess the relationship between the expression of inducible nitric oxide synthase (iNOS) and the p53 gene as well as the pathoge- nesis of choledochal cysts. METHODS: iNOS and p53 were detected by immunohisto- chemistry staining in 26 patients with congenital choledo- chal cysts. Histopathologically, hyperplasia of the mucosa of the cysts and the amylase level in the bile were also inve- stigated. RESULTS: Patients with a high level of amylase in the bile had higher expression of iNOS than those with a low level of amylase. p53 protein was expressed neither in fusiform type nor in cystic type. The incidence of mucosal hyperpla- sia was significantly higher in the fusiform type than that in the cystic type. CONCLUSIONS: Higher expression of iNOS may partici- pate in hyperplasia and carcinogenesis of the mucosa of choledochal cysts. The regurgitation of pancreatic juice in- to the biliary system might induce mucosal hyperplasia of the biliary tract and inflammatory reaction. In preventing regurgitation-caused hyperplasia and malignancy of the bi- liary tract, early surgery is important for children with con- genital choledochal cysts.

Technical note on complete excision of choledochal cysts

BACKGROUND: Choledochal cysts are congenital cystic dilatations of the extrahepatic or intrahepatic portion of the biliary tree. Complete excision of choledochal cysts is currently regarded as the gold standard treatment, while less extensive procedures including cystoduodenostomy have become obsolete due to the potential for malignant change in the remnant cyst. For type-1 choledochal cysts, which sometimes extend to the main pancreatic duct closely, some surgeons may adopt a less aggressive approach in order to avoid damage to the main pancreatic duct as such damage can lead to serious consequences. However, incomplete excision of choledocha cysts may also cause problems. METHOD: Here we report on a reoperation treating incomplete excision of a choledochal cyst with focus on the technical aspect. RESULTS: In the reoperation, meticulous dissection of the live hilum which had been previously operated on was performed The hepaticojejunostomy was left intact. With the assistance o intraoperative cholangiography, the residual pancreatic portion of the choledochal cyst was completely excised. The pancreatic opening and the lower end of the common bile duct were reconstructed. Whipple operation was avoided. CONCLUSION: Careful planning with the aid of precise imaging before and during the operation largely enhanced the accuracy of the excision of the choledochal cyst.

Traumatic rupture of a type Ⅳ a choledochal cyst in an adult male

Choledochal cyst (CC) is a rare, congenital anomaly of the bile ducts. We describe a 26-year-old male patient who was transferred to our hospital with a reported traumatic rupture of cystic liver lesions following a fall. At the time of injury, the patient experienced severe abdominal pain. He was found to have peritonitis and abdominal hemorrhage, which is quite rare. Laparot-omy revealed 3000 mL fluid consisting of a mixture of blood, bile and inflammatory effusion in the peritoneal cavity. The liver, gallbladder, spleen, stomach, duo-denum, small intestine, and colon appeared normal. A large cystic mass was discovered near the porta hepatis. This mass, which connected to the hepatic bifurcation and gallbladder had a 5 cm rupture in the right wall with active arterial bleeding. Abdominal com-puted tomography (CT) and emergency laparotomy revealed rupture of a huge type Ⅳa CC. The patient was successfully managed by primary cyst excision, cholecystectomy, and Roux-en-Y end-to-side hepatico-jejunostomy reconstruction. The postoperative course was uneventful and the patient was discharged on the 12 th day of hospitalization. Four weeks after surgery,abdominal CT scan showed pneumatosis in the intra-hepatic bile duct, and intrahepatic dilatation which decreased following adequate biliary drainage. The patient has remained well in the close follow-up period for 9 mo.

Prenatal diagnosis of choledochal cyst using magnetic resonance imaging: A case report

Choledochal cysts are congenital anomalies of the biliary ducts, characterized by cystic dilatation of the ducts.Prenatal diagnosis of this anomaly using ultrasonography (US) has been well documented. Magnetic resonance imaging (MRI) has recently become an important complement to US in prenatal diagnosis of fetal anomalies. We herein report a patient in whom at 24 wk' gestation US suggested a right upper quadrant abdominal cyst and in whom at 26 wk' gestation MRI more clearly delineated the cyst and its surrounding structures and suggested a choledochal cyst, which was confirmed at postnatal surgery and histopathology.

Recent advances in choledochal cysts

Choledochal cysts are a congenital anomaly, and they show dilatation of the intra- or extrahepatic biliary tree. These cysts are uncommon in Western countries, but are not rare in Asian countries. Choledochal cysts are classified into five groups based on location or shape of the cysts. Types I and IV-A cysts are the most common types, which are associated with anomalous pancreaticobiliary junction (APBJ), but other cysts are not associated with APBJ. Types I and IV-A cysts appear to belong to a different category from other cysts embryologically. Type I and IV-A cysts accompany anomalies of the pancreas. Type I and IV-A cysts might occur when left ventral anlage persists, and with disturbed recanalization of the common bile duct. Endoscopic retrograde cholangiopancreatography is the gold standard for detecting APBJ, but it is an invasive procedure. Magnetic resonance cholangiopancreatography (MRCP) is a non-invasive imaging tool for detecting pancreatic and biliary trees. MRCP is the first-choice modality for diagnosing choledochal cysts and APBJ in pediatric patients. Cystoenterostomy is been performed because of high complication and mortality rates. Complete excision of the cysts with Roux-en-Y hepatojejunostomy is a standard procedure for choledochal cysts to prevent postoperative complications, including development of cancer. In this study, we review classification, pathogenesis, diagnosis, and treatment of types I and IV-A choledochal cysts.