Keywords
choledochal cyst type VI - cystic duct cyst - cholecystectomy
Case Report
A 40-year-old female presented with complaints of pain in the right side of upper
abdomen which was aggravated by fatty meals for 6 months of duration. Clinical examination
of abdomen and laboratory tests were normal. Ultrasound of the abdomen revealed a
hypoechoic lesion of approximately 3 cm in size in close proximity to a thickened
gall bladder (GB) with few stones in fundus .There was no intrahepatic biliary radicle
dilatation (IHBRD). Magnetic resonance cholangiopancreatography (MRCP) revealed a
3 cm × 4 cm cyst interposed between the GB and the common hepatic duct (CHD), with
no IHBRD, CHD, or common bile duct (CBD) dilation ([Fig. 1]). A provisional diagnosis of type II/type VI choledochal cyst was made. Patient
also had an incidental congenital anomaly involving the uterus (bicornuate uterus)
seen on magnetic resonance imaging (MRI; [Fig. 2]).
Fig. 1 MRCP showing the contracted distal gall bladder (GB) with proximal cystic duct cyst
or type VI choledochal cyst extending upto the undilated common bile. CDC, choledochal
cyst; MRCP, magnetic resonance cholangiopancreatography.
Fig. 2 MRCP showing bicornuate uterus in same patient. (arrows) MRCP, Magnetic resonance
cholangiopancreaticography.
Due to concerns of adhesions and difficult dissection between the cystic duct cyst
and CHD, which may result in incomplete cyst excision, open mini-cholecystectomy with
cyst excision was planned instead of laparoscopic cyst excision and cholecystectomy.
Intraoperatively, the GB and cystic duct cyst were dissected free from the surrounding
structures and the plane between the cystic duct cyst and CHD was clearly defined.
As the communication between the cyst and CHD was small, cholecystectomy and complete
cyst excision was done.
The postoperative course was uneventful and patient was discharged on postoperative
day (POD) 3 after surgery. The specimen revealed a distal contracted GB with minute
stones in fundus with cyst proximally ([Figs. 3] and [4]). Microscopy of the GB showed features suggestive of chronic cholecystitis.
Fig. 3 Post cholecystectomy specimen with opened proximal cystic duct cyst (forceps).
Fig. 4 Post cholecystectomy specimen-longitudinal section showing proximal dilated cystic
duct cyst and distal thickened gall bladder (GB) with small stones. CDC, choledochal
cyst.
Discussion
Choledochal cysts (CDC) commonly cause dilations in the extrahepatic bile ducts. They
are classified by Todani et al[1] into five subtypes where type I CDC is the most common, (60%) causing fusiform dilation
of the common biliary duct apparatus. Type II involves saccular diverticulum of the
CBD, type III involves perivaterian part of CBD, type IV involves multiple focal dilations
of the bile ducts which are further subdivided into extrahepatic with intrahepatic
involvement (4a) and extra hepatic involvement only (4b). Type V involves the intrahepatic
bile ducts only (Caroli's disease).
Serena Serradel et al[2] modified the widely accepted and used classification of Alonso–Lej which was previously
modified by Todani et al[1] to include cystic duct cysts as a separate entity. Though the first such case was
described by Bode and Aust in 1983,[3] these lesions are very rare and only a few cases have been described in literature
([Table 1]).
Table 1
List of cases of type 6 choledochal cysts reported in literature
|
Author
|
No of cases
|
Year
|
Finding
|
Associated biliary anomalies
|
Diagnosis: intraoperative/preoperative (I/P)
|
Management
|
|
Bode and Aust[3]
|
1
|
1983
|
Dilated cystic duct cyst with narrow neck
|
Cholangitis
|
I
|
Cholecystectomy, cyst excision, choledochoduodenostomy
|
|
Champetier et al[4]
|
2
|
1987
|
Not known
|
Case 1: CBD cyst, case 2: cholelithiasis
|
P
|
Case 1: excision of cyst with bile duct cyst and cholecystectomy; case 2: excision
of cyst with cholecystectomy
|
|
Serena Serradel et al[2]
|
1
|
1991
|
Cystic dilatation of cystic duct
|
Cystolithiasis
|
I
|
Cholecystectomy, cystic duct excision
|
|
Loke et al[5]
|
1
|
1999
|
Dilated cystic duct with wide opening into the CBD
|
Cystolithiasis
|
I
|
Cholecystectomy, cyst excision with RYHJ
|
|
Bresciani et al[7]
|
1
|
1998
|
Cyst of cystic duct
|
Anomalous duct joining the cyst to right hepatic duct
|
I
|
Video laparoscopic en bloc resection of cyst and GB with ligature with a clip of the
cystic duct and anomalous duct
|
|
Baj et al[8]
|
1
|
2002
|
Fusiform dilatation, wide opening
|
NA
|
P
|
Patient refused surgery
|
|
Weiler et al[9]
|
1
|
2003
|
Not known
|
APBDJ
|
P
|
Excision of cyst, CBD with cholecystectomy and RYHJ
|
|
Manickam et al[10]
|
1
|
2004
|
Not known
|
APBDJ
|
NA
|
Excision of cyst with cholecystectomy
|
|
Yoon[11]
|
3
|
2011
|
Case 1: fusiform dilatation of cystic duct; case 2: fusiform dilatation joining by
a wide opening; case 3: fusiform dilatation with wide opening in the CBD
|
Case 1: advanced carcinoma GB with lymphadenopathy; case 2: fusiform dilatation of
CBD; case 3: CBD dilatation, GB polyps
|
P
|
Case 1: not known; case 2: refused surgery; case 3: cyst excision, RYHJ
|
|
Chan et al[12]
|
1
|
2009
|
Fusiform dilatation with narrow opening in CBD
|
Cholelithiasis, chronic Intraoperative
|
I
|
Laparoscopic excision of the cyst with cholecystectomy
|
|
Conway et al[13]
|
1
|
2009
|
Fusiform dilatation with narrow opening in CBD
|
Intraoperative
|
I
|
Excision of cystic duct cyst with cholecystectomy
|
|
Ghatak[14]
|
1
|
2010
|
Saccular dilatation
|
Fusiform dilatation of CBD Not known
|
NA
|
Excision of cyst, CBD, RYHJl
|
|
Khanna et al[15]
|
1
|
2010
|
Cystic dilatation with wide opening into the common bile duct
|
–Dilation of CHD, CBD
–Carcinoma gall bladder
|
P
|
Excision of cyst, gall bladder, and common hepatic duct with hepaticojeunostomy
|
|
De et al[16]
|
1
|
2011
|
Cystic duct cyst with wide opening into CBD and normal distal CBD
|
Cholecystitis Intraoperative
|
I
|
Excision of cyst, gall bladder, and distal CBD, hepaticoenterostomy
|
|
Maheshwari[17]
|
10
|
2012
|
Fusiform dilatation in six, saccular dilatation in four
|
1 case-fusiform CBD dilation
1 case-cystic duct calculi and malignancy
|
P
|
Surgical management of cyst: five cases, details of surgery not known Surgery for
other indications, no of intervention for cystic duct cyst: 1 case; expectant management:
3 cases; refused follow-up: 1 case
|
|
Shah et al[18]
|
1
|
2013
|
Cystic dilatation with wide opening
|
Cholecystitis
|
P
|
Excision of cystic duct and part of CBD with RYHJ
|
|
Mishra et al[19]
|
2
|
2013
|
Case 1: fusiform dilatation with wide opening; case 2: fusiform dilatation of CBD
with a wide opening
|
Case 1: CBD, diverticulum, Preoperative choledochocele, cholelithiasis; case 2: dilated
CBD, right and left hepatic ducts, cholelithiasis
|
P
|
Case 1: excision of CDC with RYHJl, deroofing of the choledochocele; case 2: CDC excision with RYHJ
|
|
Kesici et al[20]
|
1
|
2013
|
Fusiform dilatation of cystic duct
|
Cholelithiasis
|
P
|
Elective excision of GB and cystic duct cyst
|
|
Sethi et al[21]
|
3
|
2015
|
Case 1: cystic dilatation of cystic duct with wide opening; case 2: fusiform dilatation
of cystic duct with wide opening; case 3: cystic dilatation of cystic duct with narrow
opening
|
Case 1: carcinoma gall bladder; case 2: fusiform dilatation of hepatic duct; case
3: fusiform dilatation of both hepatic dust and common hepatic duct
|
P
|
Case 1: cholecystectomy with cystic duct cyst excision, removal of CBD with RYHJ;
case 2: cholecystectomy with cystic duct excision, and CBD excision with RYHJ; case
3: open cholecystectomy with complete excision of extra hepatic biliary ducts with
RYHJ with right and left hepatic ducts separately
|
|
Çamlıdağ et al[22]
|
1
|
2015
|
Fusiform dilatation of the cystic duct with the CBD; cholangiocarcinoma in distal
part of both cystic duct and CBD
|
|
P
|
Whipple's operation
|
|
Nambiar et al[23]
|
1
|
2016
|
Fusiform dilatation of the cystic duct with GB with distal CBD including intrapancreatic
portion
|
|
P
|
Lap converted to open cyst excision with cholecystectomy with hepaticojejunostomy
|
|
Ray et al[24]
|
1
|
2017
|
Fusiform dilation of cystic duct with no IHBR
|
|
P
|
Laparoscopic cholecystectomy
|
|
UpadhyayaVD[28]
|
3
|
2018
|
dilated cystic duct (3)
|
dilated CBD(3)
|
I(3)
|
Cyst excision with RYHJ(3)
|
|
This case
|
|
2019
|
Fusiform dilation of cystic duct with no IHBR
|
|
P
|
Open cholecystectomy
|
Abbreviations: APBDJ, abnormal pancreaticobiliary duct junction; CBD, common bile
duct; CDC, choledochal cysts; GB, gall bladder; IHBR, intrahepatic biliary radicle;
N/A, not available; RYHJ, Roux-en-Y Hepaticojejunostomy.
Most of these cystic duct lesions are symptomatic with most common symptom being epigastric
and/or right upper quadrant pain aggravated by a fatty meal (as in this case). Although
the exact etiology of these cysts is unknown, type VI CDC is thought to occur due
to ectasia at the cystic duct caused by an abnormal pancreaticobiliary duct junction
(APBDJ).[3]
[7]
[13]
[16] An abnormal APBDJ is, however, not seen in all cases and a focal aganglionosis of
the cystic duct, such as seen in Hirschsprung's disease, is thought to play a role.[25]
Abdominal ultrasonography is commonly the initial investigation and an MRCP is ideal
to delineate the entire biliary system including the course of the cystic duct, presence
or absence of ABBDJ, GB thickening, presence of gall stones, IHBRD, and CBD involvement.
Endoscopic retrograde cholangiopancreatography (ERCP) is invasive, though providing
the same information and detail regarding the biliary system as MRCP. ERCP and Tc-99m
Hydroxy Imino Diacetic Acid (HIDA) scan can be used for diagnosis but are not commonly
used.
Typical radiologic abnormalities that are specific to type VI CDC includes dilatation
and squaring of the cystic duct, acute angulation of the CHD, and cystic duct junction
with a distinct plane present between the dilated cystic duct and CHD, a normal or
wide (Mirrizi's syndrome) opening of the cystic duct to the CBD, a normal CBD, and
associated APBDJ.[26] Most common differential diagnosis is a type II or type I CDC due to similarities
in appearance of cyst in close proximity to CBD. Type VI choledochal cysts can further
be described based on morphology as fusiform (more common) and saccular.
As the epithelium of these cysts are prone to develop biliary intraepithelial neoplasia
(BIN), onus must be placed on complete surgical excision and multiple cut sections
of the histopathology specimen must be analyzed.[6] This is the rationale for complete surgical excision of the cyst along with cholecystectomy.[27]
Hence, the treatment for symptomatic cystic duct cysts is cholecystectomy with complete
excision of the cystic duct cyst.[1]
[5] For cysts with narrow opening of the cystic duct cyst into CHD, cholecystectomy
with complete cystic duct excision alone would suffice and it can be done through
laparoscopy by clipping the cyst opening into the CHD.[7]
[16] However, if the communication between the cystic duct cyst and CHD is wide, with
adhesions precluding safe clipping, an open cyst excision along with Roux-en-Y hepaticojejunostomy
as reconstruction may be performed.[7]
[16]
Bresciani et al,[7] Chan et al,[12] and Ray et al[24] have reported on the laparoscopic management of the cystic duct cysts where the
most common surgery is a laparoscopic cholecystectomy with cystic duct cyst excision.
Laparoscopic cholecystectomy with cyst excision can be done with low threshold for
conversion to open cholecystectomy in case of anatomical difficulty and associated
biliary anomalies which are seen in most reported cases in literature. ([Table 1])
Conclusion
The increasing use of MRCP to diagnose hepatobiliary problems will result in an increasing
number of such cystic duct dilations in the near future. In today’s laparoscopic era,
many surgeons may also be faced with such cysts intraoperatively when they are operating
on cases of acute cholecystitis or symptomatic biliary cholelithiasis. Hence, knowledge
of type VI CDC, its diagnosis by MRCP, and treatment options are the need of the hour
for effective treatment and management of this rare entity.
