Preoperative MRI Assessment for Predicting Surgical Difficulty during Laparoscopic Cholecystectomy for Acute Cholecystitis

Abstract

Introduction: The thickening of the gallbladder wall with low signal intensity on MRI in acute cholecystitis (AC) is associated with severe inflammation with necrosis and fibrosis. However, the associations between MRI findings and operative outcomes are unknown. This study aimed to assess the utility of MRI to predict surgical difficulty during laparoscopic cholecystectomy (LC) for AC. Methods: We retrospectively identified patients who underwent both preoperative MRI and early LC for AC between 2012 and 2018. Based on the signal intensity of the gallbladder wall on MRI, we classified the patients into High Signal Intensity (HSI) group and Low Signal Intensity (LSI) group. Conversion rates to open cholecystectomy and operative time were compared between the two groups. Results: Of 608 LCs performed for AC, 203 cases were eligible. Conversion rates were 5.3% (8 of 150 cases) and 26.4% (14 of 53 cases), and operative time were 100.5 min and 121 min in the HSI and LSI group, respectively (both P < 0.001). On multivariate analysis, the low signal intensity of the gallbladder wall on MRI was an independent predictor of both higher conversion rate (odds ratio 5.87, 95% confidence interval (CI) 1.72-20.00, P = 0.0047) and prolonged operative time (regression coefficient 19.99, 95% CI 6.26-33.73, P = 0.0046). Conclusions: The low signal intensity of the gallbladder wall on MRI was significantly associated with a higher conversion rate and prolonged operative time of LC for AC. Preoperative MRI could be a novel method for predicting surgical difficulty during LC for AC.