Laparoscopic excision of a Type II choledochal cyst with cystolithiasis.

Choledochal cysts can present with abdominal pain, jaundice and stones.MRI is the standard imaging tool and the type of biliary enteric anastomosis depends on the cyst type.

INTRODUCTION

Choledochal cyst (CDC) is a rare congenital dilatation of the bile ducts. The estimated incidence varies between 1 in 100,000 and 1 in 150,000. The incidence is higher in women, with a male-to-female ratio of 1:3.

CASE REPORT

A 22 year old female presented with the complaints of right hypochondria pain, fever and loose stools for 2 weeks. The patient had no jaundice, clay-coloured stools or pruritus. Liver function tests and total leucocyte counts were normal, and ultrasound showed the presence of stones in the gall bladder and hence a differential diagnosis of a double gall bladder was made. Magnetic resonance cholangiopancreatography (MRCP) of the biliary system showed a saccular dilatation in the region of the hepatic duct with multiple calculi [Figure 1]. The patient was taken for laparoscopy where a type 2 presents as a diverticulum—consistent CDC was identified.

Figure 1

Magnetic resonance cholangiopancreatography showing two saccular dilatations

On laparoscopy, the gall bladder fossa showed two saccular swellings and a CDC was identified [Figure 2]. It was an outpouching (lateral diverticulum) from the common hepatic duct, just proximal to the insertion of the cystic duct. The CDC was carefully dissected and the mouth of the diverticulum was clipped and divided [Figure 3]. The cyst was dissected free, and cholecystectomy and complete excision of the cyst was done. Histopathology showed a normal gall bladder, and the CDC showed a fibrocollagenous stroma with multiple stones.

Figure 2

The gall bladder and the choledochal cyst at the start of dissection

Figure 3

The clips after excision of cyst and the gall bladder

DISCUSSION

CDCs represent a congenital, non-familial, anomalous dilatation of the biliary system.[1] The widely accepted theory is that cystic dilatation is related to an anomalous pancreaticobiliary ductal union (APBDU) leading to biliary reflux, causing inflammation and dilatation. In a study conducted by Song et al.,[2] APBDU accounted for 56%–95% of the cases of CDCs. Abnormal function and spasm of the sphincter of Oddi may result in pancreatic juice reflux into the biliary tree, resulting in a cyst formation. Obstruction of the common bile duct is another aetiological theory for CDCs.

CDCs are classified as Type I to Type V, as shown in Figure 4. They are classified by Todani et al. into five subtypes.[3] The classic triad of jaundice, right upper quadrant mass and abdominal pain is a rare presentation, with two of the symptoms seen most commonly in children (85%) than in adults (15%). Often, CDCs present with biliary dyskinesia, stones, pancreatitis, hepatic abscess and cholangitis.[45] Ultrasound shows a characteristic cystic or fusiform dilatation of the common hepatic duct or the intrahepatic duct, distinct from the gall bladder.[6] MRCP is the diagnostic method of choice for biliary ductal pathologies and is a safe, non-invasive pre-operative investigation.

Figure 4

The type of choledochal cysts

Cystolithiasis (soft, earthy and pigmented) is seen in 70% of CDCs. Pancreatitis is another complication caused by activation of enzymes due to reflux caused by the anomalous union of the ducts. Portal hypertension may arise due to secondary hepatic fibrosis with a higher association with Caroli's disease. Cholangitis is a common complication and may be the only presenting feature. In older patients with repeated cholangitis and marked pericystic inflammation, this disease may be best managed with resection of the anterolateral part of the cyst followed by an endocystic resection of the lining, leaving the back wall adjacent to the portal vein in place, as reported by Lilly.[7] The most common malignancies are cholangiocarcinoma and adenocarcinoma. The prognosis for cholangiocarcinoma arising from the cyst is grim, with survival in the range of 6–20 months.

TYPE II CHOLEDOCHAL CYST WITH CYSTOLITHIASIS

The mainstay of management in CDC is complete excision followed by a biliary-enteric anastomosis as there is a concern of malignant transformation in these cysts. There is a high incidence of cholangitis secondary to stricture (10%–25%) following the anastomosis.[8] The clinical results of total cystectomy and Roux-en-Y hepaticojejunostomy have been excellent. Studies have found the cumulative incidence of subsequent biliary malignancy to be 1.6% at 15 years, 3.9% at 20 years and 11.3% at 25 years after cyst excision, suggesting that the risk of biliary malignancy in the remnant bile duct increases more than 15 years after cyst excision[910] and there is a need for lifelong follow-up.[11]

The treatment of choice for Type II cysts arising as a lateral diverticulum of the common bile duct is surgical excision. Depending on the size of the neck of the cyst at the junction with the common bile duct, the neck may be closed primarily or with T-tube decompression of the common bile duct.

Laparoscopic excision and biliary-enteric anastomosis have been reported in literature, and more than 200 cases have been documented predominantly from the Far East.[1213] Increasing familiarity with intracorporeal suturing and better optics have advanced procedures on the biliary tree. Robotic-assisted laparoscopic surgery has also been documented.[14]

This is a rare clipping of a diverticulum-like, Type II CDC.

Declaration of patient consent

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Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.