Ultrasound-MR fusion imaging combined with intraductal cooling via PTCD during microwave ablation of perihilar liver tumors: a retrospective pilot study.

Purpose: To explore the feasibility and safety of a microwave ablation (MWA) strategy involving intraductal chilled saline perfusion (ICSP) via percutaneous transhepatic cholangial drainage (PTCD) combined with ultrasound-magnetic resonance (US-MR) fusion imaging for liver tumors proximal to the hilar bile ducts (HBDs).

Methods: Patients with liver tumors proximal to the HBDs (≤5 mm) who underwent MWA at our hospital between June 2020 and April 2023 were retrospectively analyzed. The strategy of US-MR fusion imaging combined with PTCD-ICSP was used to assist the MWA procedures. The technical success, technique efficacy, local tumor progression, intrahepatic distant recurrence and complications were recorded and analyzed.

Results: In total, 12 patients with 12 liver tumors were retrospectively enrolled in this study. US-MR fusion imaging was utilized in all patients, and PTCD-ICSP assistance was successfully used for 4 nodules abutting HBDs (0 mm). The rates of technical success, technique efficacy, local tumor progression and intrahepatic distant recurrence were 91.7%, 83.3%, 0% and 8.3%, respectively. The major complication of biliary infection occurred in only one patient who had previously undergone left hemihepatectomy and bile-intestinal anastomosis.

Conclusions: MWA for liver tumors proximal to HBDs assisted by US-MR fusion imaging combined with PTCD-ICSP was feasible and safe. This strategy made MWA of liver tumors abutting HBDs possible.