Abstract: Objective The aim of this study was to summarize Bismuth-Corlette typing of patients with hilar cholangiocarcinoma (HCCA) by CT multimodal reconstruction. Methods 37 patients with HCCA were admitted to our hospital between January 2023 and January 2025, all underwent multi-slice spiral CT scan and multiplanar reconstruction (MPR), three-dimensional volume rendering (VR) and maximum intensity projection (MIP) were reconstructed. Taking Results of surgical tissue pathological examination as the golden standard, diagnostic efficacy for Bismuth-Corlette classifications and lymph node metastasis by CT scan was evaluated. Results Of the 37 patients with HCCA, surgical tissue histopathological examination found Bismuth-Corlette type I in 5 cases, type II in 9 cases, type IIIa in 7 cases, type IIIb in 7 cases and type IV in 9 cases, and the overall diagnostic accuracy rate by CT multimodal reconstruction for Bismuth-Corlette classifications was 83.8% (31/37), with Kappa of 0.795 (P<0.001), and especially, the diagnostic accuracy for type Ⅱ and Ⅲa were 88.9% (8/9) and 85.7% (6/7), respectively; liver histopathological examination found lymph node metastasis in 17 cases (45.9%), and CT multimodal reconstruction diagnosed in 14 cases, with sensitivity of 82.4%, specificity of 80.0%, accuracy of 81.1%, positive predictive value of 77.8%, negative predictive value of 84.2% and Kappa of 0.621, suggesting good consistency(P<0.001). Conclusion CT multimodal reconstruction could clearly depict lesion boundary, involved vessels and lymph node metastasis in patients with HCCA, with perfect evaluation of tumor staging and lymph node metastasis, which might help make subsequent surgical planning and predict prognosis.

Key words: Hilar cholangiocarcinoma, CT multimodal reconstruction, Bismuth-Corlette classification, Lymph node metastasis, Diagnosis