{'fraction_non_alphanumeric': 0.03201196709050112, 'fraction_numerical': 0.02393418100224383, 'mean_word_length': 5.185013876040703, 'pattern_counts': {'":': 0, '<': 2, '<?xml version=': 0, '>': 4, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
ANATOMICAL VARIATIONS OF EXTRA HEPATIC BILIARY SYSTEM IN PATIENTS UNDERGOING LAPAROSCOPIC CHOLECYSTECTOMY IN CMH & PEMH RAWALPINDI

Objective: To assess the frequency of anatomical variations of the extra-hepatic biliary tract in patients undergoing laparoscopic cholecystectomy in Combined Military Hospital & Pak Emirates Military Hospital Rawalpindi. Study Design: Comparative cross-sectional study. Place and Duration of Study: Department of General Surgery, Combined Military Hospital & Pak Emirates Military Hospital, Rawalpindi, from Mar to Aug 2017. Methodology: A total of 136 patients of either gender with cholelithiasis of more than one month were included. Participants were distributed into equal number of groups for both hospitals by lottery method. All the participants had under gone laparoscopic cholecystectomy by consultant general surgeon or senior registrar under direct supervision. Structures mainly assessed for variations were gall bladder, cystic duct, common hepatic duct, supraduodenal part of common bile duct, cystic artery, and hepatic artery which were characteristically encountered during laparoscopy. Results: Overall Extra hepatic biliary variations were 136 (23%), at Combined Military Hospital 68 (16%) and Pak Emirates Military Hospital 68 (29.4%). Gall bladder anomaly was seen in 3% patients, cystic duct anomaly 4.4%, supraduodenal part of common bile duct anomaly 0.7%, cystic artery anomaly 11% and hepatic artery anomaly was seen in 3.6% patients (p>0.05). Conclusion: Anatomic variations were found to be not uncommon in our set up. Thus, there is a need for doctors to continuously refresh knowledge of normal anatomy and the variants of biliary tract.


INTRODUCTION
Cholelithiasis is a worldwide surgical problem with anatomical, geographical, racial and ethnic variations 1 . Alexander trallianus first described gall stones within bile duct and it was first reported by Fallopius and Vesalius in gallbladder by 16th century during dissection 2 .
Its treatment is only surgical which is cholecystectomy. First cholecystectomy was performed in 1882 by Langenbuch 4 by a large right subcostal incision. Humanity had to wait for a decade for smaller incision cholecystectomy i.e., laparoscopic. First cholecystectomy via laparoscopy was performed in 1987 5 .
Laparoscopic cholecystectomy (LC) has supplanted open cholecystectomy and now is the operation of choice for biliary tractailments. More than 90% elective and 70% of emergency cholecystectomy is carried out via laparoscopic approach making LC as one of the frequently perform surgery globally 6 .
Biliary injury is a commonly encountered complication after LC, increases to 0.8% with the advent of laparoscopy while open cholecystectomy remains 0.2-0.3% mostly from inability to outline Calot's triangle anatomy. Typical biliary tract anatomy is found in only 20-40% of cases 7 .
Extra hepatic biliary tract (EHBT) comprises of four parts. Cystic duct and gall bladder, right and left hepatic ducts, common hepatic and bile duct and the pancreatic and intraduodenal parts 8 .
Variation in the anatomy of EHBT is significant, as failure to identify these will lead to accidentalduct ligation, biliary leaks and stricture after LC [8][9][10] .
LC is a routine procedure in our setup for cholelithiasis which involves a standard four ports access with two 5mm right side ports, 12mm epigastric port whereas umbilical port remains a surgeon choice either 5mm or 12mm. Inability to identify them and their various variations in extra hepatic biliary system may result in accidental duct ligation, biliary leakage and strictures after LC, which may cause aftermath drastic suffer to patient as well as markedly reduce the cost effectiveness of laparoscopic surgery and surgeon in public. With these results in mind the operating surgeons will be more meticulous while performing LC.

METHODOLOGY
This comparative cross-sectional study was carried out at department of General Surgery of Combined Military Hospital and Pak Emirates Military Hospital Rawalpindi. Sample size of 136 was calculated using Open Epi version 2.3 Software with following assumptions confidence interval; 95% anatomical variations present: 9.6% 12 . Desired precision: 5% Total sample size (n): 136.
After approval from ethical review board, a total of 136 patients of both gender and age limits >18 years and <65 years with cholelithiasis of >1 month with informed consent were included in the study. Participants with ASA III & IV, empyema gallbladder, acute pancreatitis, obstructive jaundice and carcinoma gallbladder were excluded.
All eligible patients fulfilling inclusion criteria admitted through outpatient department (OPD) after completing full workup for surgery and anesthetic fitness. In the morning before operation, participants took bath. Surgical site was made ready under aseptic standard protocol.
All the patients undergone laparoscopic cholecystectomy by a consultant general surgeon or senior registrar as per both hospital protocols having >2 years of postfellowship experience. Gall bladder, cystic duct, common hepatic duct, supraduodenal part of common bile duct, cystic artery, and hepatic artery were assessed for variations. However, assessment of variations of hepatic ducts, portal vein, retro duodenal and pancreatic parts of CBD was not be possible because of iatrogenic injuries.
Data entered and analyzed using SPSS-23. Mean ± SD computed for quantitative variable. Frequency and percentage were calculated for all the qualitative variables. Chi-square test was used for assessment of Statistically significant. A p-value <0.05 considered significant.

RESULTS
A total of 136 patients were enrolled in this study. Mean Age was 39.592 ± 7.78 years. Majority of the patients were females 136 (79.4%). More patients belonged to ASA-I score 136 (70.5%). Variations of extra hepatic biliary tract were seen in 31 (23%) patients.
Gall bladder anomaly was seen in 3% patients, cystic duct anomaly 4.4%, supraduodenal part of common bile duct anomaly 0.7%, cystic artery anomaly 11% and hepatic artery anomaly was seen in 3.6% patients as shown in table.

DISCUSSION
Laparoscopy allows exploration of biliary tract anatomy owing to high resolution and magnification. Therefore, extrahepatic biliary system can certainly be evaluated for its anatomical variants and congenital abnormalities during LC.
Talpur et al in 2010 reported that anatomical variations were observed in 20.3% patients. Of these, 52.5% had cystic artery anomalies, 21.3% had cystic duct anomalies, 13.1% had right hepatic artery anomalies, 9.8% had gall bladder anomalies and 3.3% had common hepatic artery 9 .