Role of MRCP to determine the etiological spectrum, level and degree of biliary obstruction in obstructive jaundice
Authors: Patel Viral B. , Musa Raish K. , Patel Nikhil , Patel Shreya D. 
Published: August 2022

Context:
Obstructive jaundice as a result of hepatocellular disease many a times is indistinguishable from jaundice due to extrahepatic biliary obstruction based on just clinical and biochemical examinations. It is one of the most frequent and grave form of hepatobiliary disease which may lead to complications like ascending cholangitis, malabsorption and hepatorenal syndrome, thus demanding urgent surgical intervention. Thus not only early diagnosis but also accurate identification of level and cause of obstruction is crucial in managing these patients.

Aims:
The aim of this study is to evaluate the role of MRCP in the determination of the etiological spectrum, to evaluate level and degree of biliary obstruction in cases of obstructive jaundice, and to correlate MRCP findings with surgical/histopathology/ERCP findings where possible.

Methods and Material:
It is an observational study done after the Institutional Ethics Committee (I.E.C.)- 2 approval. (IEC no: IEC/HMPCMCE/122/Faculty/8/186/20) Outdoor and indoor patients referred to radiodiagnosis department of Shree Krishna Hospital, Karamsad, for MRCP with clinical and laboratory parameters suggesting obstructive jaundice were included in the study. Patients less than 10 years of age, those with contraindications to MRI and patients with clinico-laboratory evidence of perihepatic/hepatic jaundice were excluded.

Methodology:
A total of 50 patients were included after taking an informed consent from each patient. Demographic data, clinical details were recorded and collated along with MRI findings. Descriptive statistics was used to explore MRI findings and findings were correlated with surgical/histopathology/ERCP findings whichever applicable. The MRI scan was performed with 5 mm thick axial T1W, T2W and STIR, 5 mm thick coronal T1W, T2W and STIR TRUFIS, Thin coronal T2 FS, Thick coronal T2 FS, T2W coronal respiratory trigger sequences, 3-5 mm thick T2 weighted Haste and 3D sequence.

Statistical Analysis Used:
Analysis was performed using STATA (14.2). Descriptive statistics was used of study population. Sensitivity and specificity value was used to compare the modality and individually calculated for various causative factors of jaundice.

Results:
Of the 50 patients, 9 had CBD stones, it is observed that MRCP has sensitivity and specificity of 100% and 100%, respectively, in detecting Bile duct stones, whereas sensitivity and specificity of ERCP was 87.5% each.
About 11 patients had CBD strictures, which were seen as narrowing of CBD with upstream dilatation. It was observed in our study that the sensitivity of MRCP was 93% and specificity was 95% in detecting CBD strictures while ERCP had 100% sensitivity and specificity. About 12 patients had CBD tumor for sensitivity and specificity of MRCP and ERCP was 100%. Out of 50 patients, 36% had gall bladder stones in whom MRCP sensitivity and specificity was 88.89% and 100% and was found to comparable with ERCP. Only three patients in our study had ampullary carcinoma out of which the sensitivity and specificity came 100% for MRCP. One patient, in whom MRCP and HPE detected ampullary carcinoma, ERCP detected no ampullary carcinoma thus favoring MRCP. However, owing to inadequate study population results are inconclusive. There is significant difference between MRCP and ERCP accuracy rate in detection of ampullary carcinoma. Therefore, our study which is more in favor of MRCP. There were 78% patients who were detected with biliary duct dilatation in ERCP, which was equally detected in MRCP. Thus MRCP had 100% sensitivity and specificity in detecting biliary duct dilatation compared to ERCP. Pancreatic dilatation was detected in four patients and there were two patients who were detected with ampullary stones and its sensitivity, specificity came up to 100% compared to ERCP. Conclusion: Thus to conclude, MRCP has high sensitivity for CBD such as stones, strictures and malignancies therefore to avoid unnecessary diagnostic ERCP; in cases with suspicion (clinical/CBD-IHBR dilatation on USG) of choledocholithiasis/ampullary stone, MRCP is recommended.