Insight into microvascular adaptive alterations in the Glisson system of biliary atresia after Kasai portoenterostomy using X-ray phase-contrast CT.

Objectives: To investigate microvascular alterations in the Glisson system of biliary atresia (BA) patients after Kasai portoenterostomy (KP) using three-dimensional (3D) virtual histopathology based on X-ray phase-contrast CT (PCCT).

Methods: Liver explants from BA patients were imaged using PCCT, and 32 subjects were included and divided into two groups: KP (n = 16) and non-KP (n = 16). Combined with histological analysis and 3D visualization technology, 3D virtual histopathological assessment of the biliary, arterial, and portal venous systems was performed. According to loop volume ratio, 3D spatial density, relative surface area, tortuosity, and other parameters, pathological changes of microvasculature in the Glisson system were investigated.

Results: In the non-KP group, bile ducts mostly manifested as radial multifurcated hyperplasia and twisted into loops. In the KP group, the bile duct hyperplasia was less, and the loop volume ratio of bile ducts decreased by 13.89%. Simultaneously, the arterial and portal venous systems presented adaptive alterations in response to degrees of bile duct hyperplasia. Compared with the non-KP group, the 3D spatial density of arteries in the KP group decreased by 3.53%, and the relative surface area decreased from 0.088 ± 0.035 to 0.039 ± 0.015 (p < .01). Deformed portal branches gradually recovered after KP, with a 2.93% increase in 3D spatial density and a decrease in tortuosity from 1.17 ± 0.06 to 1.14 ± 0.04 (p < .01) compared to the non-KP group.

Conclusion: 3D virtual histopathology via PCCT clearly reveals the microvascular structures in the Glisson system of BA patients and provides key insights into the morphological mechanism of microvascular adaptation induced by biliary tract dredging after KP in BA disease.

Key Points: • 3D virtual histopathology via X-ray phase-contrast computed tomography clearly presented the morphological structures and pathological changes of microvasculature in the Glisson system of biliary atresia patients. • The morphological alterations of microvasculature in the Glisson system followed the competitive occupancy mechanism in the process of biliary atresia.