Prevalence of Biliary Dilatation in Patients with Pancreatitis on MDCT and Its Correlation with CT Severity Index

ABSTRACT OBJECTIVES This study aimed to determine the prevalence of biliary dilatation in patients with pancreatitis on multidetector computed tomography (MDCT) and to evaluate its association with the CT Severity Index (CTSI). METHODOLOGY Analytical cross-sectional study. Department of Radiology, Rehman Medical Institute, Peshawar, from 1st August 2022 to 31st July 2023. A total of 146 adult patients with clinically suspected or confirmed pancreatitis who underwent contrast-enhanced MDCT were included through non-probability consecutive sampling. Patients with prior hepatobiliary surgery, pancreatic or hepatobiliary malignancy, or incomplete imaging were excluded. Biliary dilatation was defined as a common bile duct diameter >7 mm in patients <60 years and >8 mm in those ≥60 years. The CT Severity Index (CTSI) was calculated using the Balthazar grading system. Image interpretation was performed independently by two experienced radiologists, and interobserver agreement was assessed using Cohen’s kappa statistic. The association between biliary dilatation and CTSI categories was analyzed using the Chi-square test for trend. Prevalence estimates were reported with 95% confidence intervals (CI). Statistical analysis was performed using SPSS version 26.0, with p < 0.05 considered significant. RESULTSThe mean age of patients was 43.68 ± 11.20 years, and 79 (54.1%) were females. Biliary dilatation was observed in 54 patients (37.0%; 95% CI: 29.30-44.9). According to CTSI classification, 47 (32.2%) patients had mild, 45 (30.8%) moderate, and 54 (37.0%) severe pancreatitis. The proportion of biliary dilatation increased with disease severity, occurring in 13 (27.7%) mild, 15 (33.3%) moderate, and 26 (48.1%) severe cases. Although this trend suggested increasing biliary involvement with greater disease severity, the association did not reach statistical significance (p = 0.086). Interobserver agreement for CT interpretation demonstrated substantial reliability (κ = 0.82). CONCLUSION Biliary dilatation is a relatively common MDCT finding in patients with pancreatitis and shows an increasing trend with higher CTSI categories. Although the association was not statistically significant, careful CT evaluation of the biliary system may help identify patients who may benefit from further biliary assessment or targeted clinical management.