Radiofrequency energy induced heating of bovine capsular tissue: in vitro assessment of newly developed, temperature‐controlled monopolar and bipolar radiofrequency electrodes

This in vitro investigation characterized temperature changes associated with radiofrequency (RF) energy induced heating of bovine capsular tissue using newly developed, temperature-controlled monopolar (Vulcan RF system and Vulcan, TAC-S Electrothermal Probe) and bipolar (VAPR II RF system and VAPR TC RF electrode) RF systems and electrodes. Bovine capsular tissue samples were placed in a saline bath maintained at room temperature. Both RF generators were used at settings of 75 degrees C and 40 W. The RF electrodes were placed in stationary positions on the tissue samples and activated for 1- to 10-s. A fluoroptic thermometry system was utilized to record temperatures at the RF electrode-tissue interface at 1-s intervals. The results indicated that the mean tissue temperatures for the monopolar RF electrode tended to be higher than those produced by the bipolar RF electrode, especially during the 2- to 10-s RF delivery time intervals (P<0.05). Notably, during the 2- to 10-s time intervals the monopolar RF electrode produced mean tissue temperatures that exceeded the set temperature of 75 degrees C (range of differences +1.2 to +15.7 degrees C highest mean temperature 90.7 degrees C). By comparison, the bipolar RF electrode maintained tissue temperatures relatively close to the set temperature(range of differences -3.2 to +2.7 degrees C; highest mean temperature 77.7 degrees C). These findings provide basic temperature profiles for the two new temperature-controlled RF devices.