Towards realistic radiofrequency ablation of hepatic tumors 3D simulation and planning

摘要

Radiofrequency ablation (RFA) has become an increasingly used technique in the treatment of patients with unresectable hepatic tumors. Evaluation of vascular architecture, post-RFA tissue necrosis prediction, and the choice of a suitable needle placement strategy using conventional radiological techniques remain difficult. In an attempt to enhance the safety of RFA, a 3D simulator and treatment planning tool, that simulates the necrosis of the treated area, and proposes an optimal placement for the needle, has been developed. From enhanced spiral CT scans with 2 mm cuts, 3D reconstructions of patients with liver metastases are automatically generated. Virtual needles can be added to the 3D scene, together with their corresponding zones of necrosis that are displayed as a meshed spheroids representing the 60℃ isosurface. The simulator takes into account the cooling effect of local vessels greater than 3mm in diameter, making necrosis shapes more realistic. Planned needle positioning can also be automatically generated by the software to produce complete destruction of the tumor, with maximum respect of the healthy liver and of all major structures to avoid. If he wishes, the radiologist can select on the skin an insertion window for the needle, focusing the research of the trajectory.