Thermal Ablation of Hypervascular Liver Tumors After Selective Intra-Arterial Lipiodol Injection (SIALI): A Technical Narrative Review of Technique, Institutional Variations, and Published Evidence

PURPOSE: Percutaneous thermal ablation of hypervascular liver tumors is limited by lesion conspicuity on conventional imaging, challenges with ablative margin assessment, and unequal global access to advanced technologies such as ablation confirmation software and radioembolization. This review describes the selective intra-arterial lipiodol injection (SIALI) technique, its technical variations across institutions, and summarizes published clinical outcomes for SIALI-guided thermal ablation of hepatic malignancies.

METHODS: A narrative review was conducted through structured searches of the PubMed, Embase, and Cochrane databases using terms including "selective intra-arterial lipiodol injection," "lipiodol-guided ablation," "SIALI," and "hepatic arterial lipiodol." Studies were selected based on relevance to SIALI technique, clinical outcomes, and comparator techniques, including hepatic arteriography with C-arm CT-guided ablation (hepACAGA) and ablation confirmation software. Full-text peer-reviewed articles were included; conference abstracts and letters were excluded. No formal PRISMA-compliant inclusion or exclusion criteria were applied, consistent with the narrative review format.

RESULTS: Seven studies were identified, encompassing six retrospective cohort studies and one prospective randomized controlled trial, collectively comprising over 900 patients treated across institutions in Asia, Europe, and the United States. Across heterogeneous patient populations and technical approaches, SIALI-guided thermal ablation was associated with improved local tumor recurrence rates, local recurrence-free survival, and overall survival compared with conventional ultrasound- or CT-guided ablation alone in selected studies where comparator data were available, with favorable technical success rates in lesions otherwise occult on standard imaging.

CONCLUSION: SIALI appears to be a technically feasible and potentially useful adjunct technique that may improve lesion conspicuity and enable real-time ablative margin assessment in the treatment of hypervascular liver tumors, particularly in settings without access to ablation confirmation software. The available evidence is predominantly retrospective, and prospective validation is needed before broad conclusions regarding oncologic outcomes can be drawn.