DynaCT biliary reconstruction via a 3D C-arm cholangiography system: clinical application in hepatolithiasis.

Objective: Dyna computed tomography (DynaCT) is an innovative clinical imaging tool used to obtain three-dimensional (3D) images of biliary structures via the Artis Zee DSA system (SIEMENS Company, Germany). DynaCT is a type of 3D cone beam computed tomography (CBCT) reconstruction produced from a two-dimensional (2D) cholangiography system by rotating the C-arm without moving the patient. The aim of this study was to evaluate the technical approach and application value of DynaCT to diagnosis hepatolithiasis and biliary stenosis.

Methods: This was a retrospective single-centre series of 37 hepatolithiasis patients with tubes receiving one-step percutaneous transhepatic cholangioscopic lithotripsy (one-step PTCSL) between October 2021 and October 2022: twenty-one patients were guided by CT (CT group) and sixteen by DynaCT biliary reconstruction (DynaCT group). We compared DynaCT biliary reconstruction technology with computed tomography (CT) in the application of bile ducts.

Results: DynaCT biliary reconstruction was successfully performed in 37 patients. Biliary stenosis, including anatomy, morphology, and size, was visualized via DynaCT. Compared with the CT group, the DynaCT group was characterized by significantly more target biliary branches with stones (92 vs. 48, P < 0.05), a higher percentage of secondary stenosis (75.76% vs. 24.24%, p < 0.05), a greater percentage of biliary infection (37.5% vs. 9.5%, P = 0.041), a shorter overall stone clearance time (26.38 ± 13.49 vs. 52.67 ± 30.10, P = 0.001), and a lower rate of reoperation for residual stones (25.00% vs. 66.67%, P = 0.012). DynaCT had a lower contrast agent (25.61 ± 5.13 vs. 42.69 ± 11.15, p < 0.05). However, DynaCT increased radiation exposure (38.12 ± 10.59 vs. 25.79 ± 4.76, p < 0.05). There were no significant differences between the two groups regarding the clearance ratio of the calculus or several postoperative complications.

Conclusion: DynaCT for biliary reconstruction has the potential to be a powerful evaluation tool for one-step PTCSL surgery and could lead to new possibilities for hepatobiliary surgery.

Advances in knowledge: DynaCT was used for the first time in patients with hepatolithiasis and biliary stenosis. Compared with CT, DynaCT for biliary reconstruction results in higher-quality 3D biliary, blood vessel and liver images. On the basis of the DynaCT biliary model, one-step PTCSL has the potential to improve the stone clearance ratio and shorten the stone clearance time and reoperation ratio.