Fig. (7).
Lesion Volume with 100% Normal Tissue Perfusion (6.4 x 10-3 mb3/mt3/s) for a 15 Minute Ablation with a Constant 22.5 Volt Source. Graph shows the total volume of tissue necroses calculated for a 15 minute ablation using a constant 22.5 volt source, using cell damage thresholds (D), isothermal temperatures (IT), and thermal dosing (C) with 100% normal tissue perfusion (6.4 x 10-3 mb3/mt3/s). The data demonstrate that volumes calculated using traditional isothermal temperatures of 42°C and 47°C grossly overestimate the rate of lesion growth. Likewise, the volume calculated using cumulative equivalent minutes at 43°C also overestimates the rate of lesion growth. The graph shows that the IT60 curve is a better approximation of cell damage calculated using either the 63% or 100% iso-damage contours methods.