# Comparative Diagnostic Accuracy of Ultrasonography and Magnetic Resonance Cholangiopancreatography (MRCP) in the Evaluation of Obstructive Jaundice: A Prospective Study in Western India

## TL;DR

This study compares ultrasound and MRCP for diagnosing obstructive jaundice and finds that MRCP is more accurate in detecting biliary and pancreatic issues.

## Contribution

The study provides empirical evidence that MRCP outperforms USG in diagnosing obstructive jaundice in a specific regional context.

## Key findings

- MRCP detected biliary dilatation and obstruction more accurately than USG.
- MRCP showed higher sensitivity and specificity for CBD stones and benign biliary pathologies.
- MRCP had a higher concordance with reference standards (κ = 0.92) compared to USG (κ = 0.56).

## Abstract

Background: Obstructive jaundice is a common clinical condition requiring accurate imaging for prompt diagnosis and management. Ultrasonography (USG) is often the first-line modality, whereas magnetic resonance cholangiopancreatography (MRCP) offers non-invasive high-resolution visualization of the biliary and pancreatic ducts. This study aimed to compare the diagnostic accuracy of USG and MRCP in obstructive jaundice and assess the efficacy of MRCP in detecting ancillary biliary and pancreatic abnormalities.

Methods: A hospital-based prospective study was conducted on 30 adult patients (age 18-75 years) with obstructive jaundice at P.D.U. Government Medical College, Rajkot, India, between November 2020 and November 2022. All participants underwent both USG and MRCP. Diagnostic performance was evaluated against the reference standard of intraoperative, histopathological, or endoscopic retrograde cholangiopancreatography findings. Sensitivity, specificity, positive and negative predictive values, accuracy, and Cohen’s kappa coefficient (κ) were calculated. Chi-square test and receiver operating characteristic curve analysis were used to compare modalities.

Results: MRCP demonstrated superior diagnostic performance compared with USG in detecting intrahepatic biliary dilatation (14 (46.7%) vs. 6 (20%), p < 0.05), common bile duct (CBD) dilatation (25 (83.3%) vs. 18 (60%), p < 0.05), and level of obstruction ((26 (86.7%) vs. 19 (63.3%), p = 0.04). For benign biliary pathologies, MRCP achieved higher sensitivity (95.6% vs. 92.3%), specificity (78.9% vs. 50%), and overall accuracy (87.2% vs. 71.1%) compared to USG. In CBD stones, MRCP outperformed USG in sensitivity (96.8% vs. 91.6%), specificity (84.9% vs. 55%), and accuracy (90.8% vs. 73.3%). MRCP demonstrated perfect diagnostic performance in bile duct dilatation, benign strictures, and tumors, with higher concordance to reference standards (κ = 0.92) than USG (κ = 0.56). Overall, MRCP provided more precise detection and characterization of biliary pathology across all parameters.

Conclusion: MRCP significantly outperforms USG in the evaluation of obstructive jaundice, particularly in detecting biliary strictures, ductal dilatation, and tumors. MRCP should be considered the preferred non-invasive diagnostic modality for comprehensive assessment of patients with obstructive jaundice, complementing USG in clinical decision-making.