Computer-aided design and evaluation of novel catheters for conductive interstitial hyperthermia.

Conductive interstitial heating is a modality in which heating elements are implanted directly into the treated tissue. One implementation of such therapy employs electrically heated catheters that are implanted in staggered, parallel rows. To explore strategies for maximising the uniformity of tissue temperature distributions achieved with heated catheters, a two-dimensional computer model with cylindrical co-ordinates was used to evaluate radially and longitudinally the temperature distributions produced by a typical interior catheter surrounded by other similar catheters. Insights from the computer model led to new designs for catheters containing multiple heating elements that produced more uniform thermal distributions, eliminating previous 'cold spots' within the treatment volume located near the ends of the catheter. The new catheter designs also include compartments for the optional placement of radioactive seeds for simultaneous thermoradiotherapy.