Analysis of tissue margins of cone biopsy specimens obtained with "cold knife," CO2 and Nd:YAG lasers and a radiofrequency surgical unit.

Analysis of the tissue margins of cone biopsy specimens obtained from 40 patients showed varying degrees of thermal and mechanical artifact at the tissue margins. The least artifact was seen in the tissue margins of specimens obtained with the scalpel ("cold knife"). The amount of thermal damage to biopsies obtained via lasers and the radiofrequency unit varied with the instrument employed. However, the quality of the tissue margins of specimens obtained using a radiofrequency surgical unit equipped with a needle electrode on a "pure cut" setting approached the quality of those obtained with the cold knife in their lack of thermal and mechanical artifact.