Background: No papers have heretofore documented histological studies of cases involving the inflammation of resected gallbladder or examined surgical difficulties on the basis of pathological findings.

Methods: On the basis of the histological inflammation findings on the resected gallbladders of 437 patients who underwent laparoscopic cholecystectomy (LC), the factors affecting the technical difficulty of the operation were examined through preoperative clinical findings (13 items), diagnostic imaging (22 items), and blood test findings (6 items), using multivariate analysis.

Results: In accordance with the four-stage classification of inflammation findings for the resected gallbladder, the inflammation findings on the resected gallbladder indicated a higher correlation with the time required for gallbladder dissection (30.2 ± 16.3 minutes) than with the operation time (77.6 ± 32.7 minutes). Thus, the technical difficulty of the operation was judged according to the time required for gallbladder dissection. For the preoperative findings on 418 patients who underwent successful LC, the most influential factors on the time required for gallbladder dissection were the presence of abnormal findings on computed tomography, the degree of fever, obesity index, nonvisualized gallbladder cholangiography, and cystic duct length. According to the multiple regression equation of these five factors, the gallbladder dissection for the 19 patients who underwent conversion to open cholecystectomy (OC) due to extreme inflammation was calculated to require 61.9 ± 12.3 minutes, and the patients who showed a gallbladder dissection time longer than 49.6 minutes were judged to have high technical difficulty predicted from the preoperative evaluation. In the preoperative evaluation, sensitivity was 79.6%, specificity was 97.6%, accuracy was 95.0%, positive predictive value was 85.0%, and negative predictive value was 96.6%. Next, each finding was scored on the basis of a multiple regression equation of five factors, and the technical difficulty of the operation was quantified using these scores. The score of the patients who underwent conversion to OC was 8.0 ± 2.0, and the patients who showed a score higher than 6 were judged to have high technical difficulty. Almost the same results as in the aforementioned preoperative evaluation were obtained using these scores.

Conclusion: The judgment using the scores was satisfactory in terms of the simplicity of evaluating the technical difficulties associated with each patient and the ease of obtaining information for each factor. The quantification of technical difficulty using the scores is useful for preoperative prediction of which patients will have difficulties in gallbladder dissection and the conversion to OC in LC. Our results suggest that the consideration of technical difficulties is important for conducting safe operations with avoiding intraoperative complications.