Laparoscopic cholecystectomy in double gallbladder with dual pathology.

Double gallbladder is a rare embryological anomaly of clinical significance. Despite availability of modern imaging, only 50% of recently reported cases had preoperative diagnosis, which is desirable in every case to avoid serious operative complications. Double pathology in double gallbladder is extremely rare with only 3 reporting's available till date to the best of author's knowledge. With a preoperative diagnosis of double gallbladder, laparoscopic cholecystectomy can be safely and successfully performed with meticulous dissection, aided by operative cholangiogram. However in all such attempts a lower threshold should be kept for conversion to open surgery. Awareness about this anomaly amongst radiologists and surgeons is of crucial importance. Double gallbladder does not present with any specific symptom, neither it increases disease possibility in either lobe. Prophylactic cholecystectomy has no role in asymptomatic cases diagnosed accidentally. Author reports a case of a symptomatic young male with double gallbladder who presented with short history of dyspepsia, abdominal pain and fever. Definite preoperative diagnosis was reached with ultrasound scan and magnetic resonance cholangio pancreatography and subsequently dealt with laparoscopically. Calculous cholecystitis affected one lobe and acalculous empyema the other. While the 1st lobe drained though a cystic duct into common bile duct (CBD), the 2nd was without any communication with either CBD or its counterpart, thus remained as a blind vesicle.

INTRODUCTION

Double gallbladder is an embryological abnormality of relative rarity (1:4000 human autopsies). This anomaly adds to the complexity of commoner anatomical variations of cysto-hepatic triangle with serious implications on surgical outcome. Modern imaging's like computerised tomogram, magnetic resonance cholangio pancreatography (MRCP) endoscopic retrograde cholangio pancreatography (ERCP) and ultrasound (US) accounts for higher incidences of pre-operative diagnosis of this anomaly than ever before. Awareness among surgeons and radiologists is of crucial importance for successful outcome, as one moiety may be missed and left behind during surgery or major biliary damage with serious consequences may happen during attempted removal.[1] Laparoscopy is the preferred choice for type-1 and open surgery for the type-2 variant.

CASE REPORT

This was a case report of a 21-year-old male patient who presented with a history of dyspepsia and occasional right upper quadrant (RUQ) pain of 1 month duration. During that period he had two episodes of pyrexia of 100F accompanying RUQ pain that lasted for couple of days and promptly responded to oral antibiotics prescribed by family physician. An abdominal US-scan was requested on relapse of fever and pain, which showed a thick walled gallbladder with stones but no other signs of acute cholecystitis. An interesting finding of the scan was an abnormal cystic structure near porta hepatis. Common bile duct (CBD) was of normal calibre without dilatation of intrahepatic biliary radicles. Two possibilities were suggested - a double gallbladder or a choledochal cyst. On the basis of the US-scan, MRCP was requested along with liver function test (LFT) and haemogram. Though afebrile at that time, his TC was 14,000 with 84% neutrophil. His LFT was normal in all its parameters. MRCP confirmed the cystic structure at porta to be the partially intrahepatic second lobe of a double gallbladder [Figure 1]. It also suggested that one stone of 2 cm is in the 1st lobe and another stone at the junction of the two lobes joined at their necks, both being drained by a short cystic duct (CD) into CBD. MRCP classifies this to type-1 V-shaped double gallbladder.

Figure 1

Magnetic resonance cholangio pancreatography showing double gallbladder with normal calibre common bile duct

A laparoscopic exploration was performed with standard 4 port technique. The 2nd moiety was immediately visible near porta, being overlapped by the 1st and occupying the cystohepatic triangle of the first moiety and found to be partially intrahepatic and in close proximity to the right hepatic duct. Dissection started on the callots triangle of 1st moiety and a rather long CD, a solitary cystic artery (CA) of significant size was dissected free [Figure 2].

Figure 2

Anatomy after initial dissection with traction on fundus (black arrow) and Hartman's pouch (white arrow) of 1st lobe, showing partially intrahepatic 2nd lobe (yellow arrow) and solitary cystic duct (green arrow) and artery (red arrow)

Operative cholangiogram (OC) was performed by direct puncture of the 1st lobe and a normal calibre CBD was delineated where the CD was draining in normal position. 2nd lobe of the gallbladder was not visualised and both the stones were demonstrated in the 1st lobe as filling defects. OC was then performed by direct puncture of the 2nd lobe using 28F spinal needle. The 2nd lobe was found to be blind with no flow of dye into CBD or its counterpart and no stone was in it. Both the lobes were adjacent and the infundibulum of 1st lobe was overlapping the second. There was a common serous coat for both the lobes with a branch of the main CA supplying the second lobe, which was partly intrahepatic. After division of the CD and CA the serous coat between the lobes were divided with control of the arterial branch supplying the 2nd lobe. This manoeuvre exposed the second lobe of gallbladder, which was dissected of the liver bed with careful and gentle blunt dissection with suction canula tip [Figure 3]. No further biliary or vascular structure was identified during this dissection. On completion of the procedure, there was no bile leak from either gall bladder fossa which was adjacent but separate. Both lobes were found to be attached only at their neck [Figure 4].

Figure 3

After division of cystic duct (CD) (black arrow) and artery the partially intrahepatic 2nd lobe is dissected off its fossa (red arrow). The slipped clip from gallbladder end of CD is shown by white arrow

Figure 4

Two lobes of gallbladder attached at their neck

Post-extraction examination of the specimen revealed that the 1st lobe contained both the stones and had thick inspissated green bile and the second lobe did not decompress on applying manual pressure. Once a nick was made into this lobe frank pus came out without a tinge of bile. Histological report showed chronic cholecystitis in the 1st lobe and features consistent with empyema in the second. Bacteriological culture of the pus did not reveal any growth of organism.

Post-operative recovery was excellent and the patient is doing well in the follow-up of over a year.

DISCUSSION

Though initially classified by Boyden, Harlaftis classification is surgically more relevant and universally accepted. Commoner variety of type-1occurs in split primordium and type-2 (often called accessory gallbladder) from double primordium during 5th and early 6th week of embryogenesis.[23] In most cases, both the gallbladders remain adjacent and invariably shares the same serous coat, however they may be apart with one component partially or completely intrahepatic. They may have independent or shared arterial supply. US have high sensitivity in detecting this condition, but lacks in specificity when compared with MRCP.[24] ERCP is the gold standard for pre-operative diagnosis.[5] Phrygian cap, choledochal cyst, folded gallbladder and diverticulum of gallbladder have similar US appearance. Pre-operative detection is only 50%,[5] leaving chance for accidental detection during surgery. Surgeons not aware of this anomaly can miss the 2nd lobe with subsequent recurrence of symptoms requiring reoperation.[16]

Unless diseased, this anomaly is of no clinical significance. Neither it has any specific symptom, nor increases the chance of occurrence of disease in either lobe.[7] Thus there is no role of prophylactic cholecystectomy in accidentally diagnosed cases. Disease process occurs in equal frequency and nature as in single gallbladder, making gallstone disease the commonest affection. Both moieties may be affected or one may be spared, however both lobes should be removed during surgery even if disease is present only in one. Though about 250 cases of double gallbladder have been reported in the literature, co-existence of two different pathologies in two lobes is extremely rare and only three reported cases available until date. Though there are similarities with an earlier reported case of dual pathologies in double gallbladder[8] with solitary CD and artery for both the lobes which shared a common infundibulum classifies this anomaly as bilobate V gallbladder unlike true duplication described in previous reporting. Between the two types, bilobate gallbladder is rarer. Like other septate variants the lobes of bilobate gallbladder usually communicate through an opening of variable size. Inflammation in the 1st lobe from calculus cholecystitis may have blocked the small opening draining the 2nd lobe causing pyocele in it, which at the time of surgery was a blind vesicle as demonstrated on OC.

The importance should be on the pre-operative diagnosis and awareness on part of surgeons about this anomaly, to successfully deal with any abnormal cystic structure around porta hepatis when first encountered during surgery. With a pre-operative diagnosis of double gallbladder, general rule is to proceed with laparoscopic cholecystectomy in type-1 variety and open procedure for type-2, as the later variant increases the possibility of biliary and vascular injury. This explains small number of successful laparoscopic procedures with type-2 variant. However, successful laparoscopic cholecystectomies have been reported in type-2 double gallbladder. Though MRCP is reasonably accurate in diagnosing the presence of this anomaly, it is not infallible in its description of the ductular anatomy and should always be supplemented by OC during surgery in every case of double gallbladder.

CONCLUSION

Double gallbladder is a rare embryological abnormality which on even rarer occasion may be associated with double pathology. Awareness of this condition amongst surgeons and radiologists is crucial as pre-operative diagnosis is desirable. Operative cholangiogram provides a real time roadmap for adjacent biliary structures and helps in reducing catastrophic complications. Meticulous dissection of cysto-hepatic triangle is mandatory in all cholecystectomies, especially so in a patient with double gallbladder. Trial laparoscopy aided by operative cholangiogram should be considered in all cases of pre-operatively diagnosed double gallbladder, keeping a low threshold of conversion to open surgery when structure identification becomes anything less than definite.