Gallbladder perforation: Diagnostic accuracy of new CT difficulty score in predicting complicated laparoscopic cholecystectomy.

Purpose: To formulate and evaluate the diagnostic performance and utility of a new CT difficulty score in predicting difficult laparoscopic surgery in cases of gallbladder (GB) perforation.

Methods: This prospective single centre study included a total of 48 diagnosed cases of GB perforation on CT between December 2021 and June 2023, out of which 24 patients were operated. A new 6-point CT difficulty scoring system was devised to predict difficult laparoscopic approach, based on patterns of inflammation around the perforated GB that were found to be surgically relevant. The pre-operative imaging findings on CT were studied in detail and correlation coefficients of various imaging findings were calculated to predict difficult surgery.

Results: On CECT, the type of perforation, according to the revised Niemeier's classification could be exactly delineated in all 48 patients. A CT difficulty score of ≥ 3 was found to a good predictor difficult laparoscopic approach, with statistical significance (p = 0.001), sensitivity of 94.44%, specificity of 83.33%, PPV of 94.44% and NPV of 83.33%. Inflammatory changes around duodenum showed maximum correlation coefficient of 0.744 (p = 0.0001), around colon showed a correlation coefficient of 0.657 (p = 0.0005), and in the omentum had a correlation coefficient of 0.5 (p = 0.013)). Inter-observer agreement was also calculated for various findings and it was found to have moderate to strong agreement (κ value 0.5-1.0).

Conclusion: The CT difficulty scoring system can be an effective tool in predicting difficult laparoscopic surgery in cases of GB perforation in an emergency setting which can help in decision making and improved patient outcome.