Abstract:
Purpose: To analyse the feasibility of directional ablation using a multi-tine electrode.
Methods: A multi-tine electrode capable of operating in multipolar mode has been used to study the directional
ablation. In addition to the basic design, similar to commercially available FDA approved multi-tine electrode,
tines have been insulated from each other inside the probe base and tip using a thin insulating material of
thickness 0.25 mm. A cylindrical single-compartment model of size 6 cm × 6 cm has been used to model normal
liver tissue. The temperature-controlled radiofrequency ablation has been employed to maintain the tine-tips at
different temperatures. Electro-thermal simulations have been performed by using a commercial multi-physics
software package based on finite element methods. To make this study feasible a new approach to predict the
ablations have been proposed and used in this study.
Results: Asymmetric ablation zone with up to 5 mm difference in ablation boundary between the intended and
non-intended direction has been observed along the transverse direction. Reduction in ablation up to 5 mm along
the axial direction in comparison to the monopolar mode has also been observed.
Conclusion: Multi-tine electrode modified to operate in multipolar mode can create directional ablations of
different shapes and can be used to target position and shape specific tumours.
