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Hyperthermia and ablation 261

Figure 8.5 The electric field and the hemodynamic flow in the general heat transfer analysis:
(A) electric current density and electric potential (max. 22 V ); (B) the pressure field (); (C) the veloc-
ity field (inlet velocity, 0.19 m/s).

The volume-averaged temperature of the tumor rise to the critical plateau is predicted
by both models, Fig. 8.7, but the BHT model tends to overestimate the RF heating effect
(Morega et al., 2020). This finding is important because if the numerical simulation is used
to aid the planning of this RF procedure then the bioheat model may be overestimating the
RFA success. Joule heating (duration, power level, not to enter into the details of the elec-
trodes and their positioning) that seems to be required for the success of the planned proto-
col would be, in fact, highly underestimated. This would mean undersizing the input power
level. Heating has to be maintained long enough, and the power level should be properly
adjusted (increased) because larger vessels are identified as significant enthalpy paths that drain
part of the power delivered by the electrode.