Safe Use of Adrenaline in Cryosurgery for Eyelid Basal Cell Carcinoma Evaluated With Infrared Thermography.

The efficacy of cryosurgery for skin cancers is believed to depend on thaw time, which may be influenced by the presence of adrenaline in local anaesthetics due to its vasoconstrictive effects. This is the first study to perform detailed, non-invasive temperature measurements using infrared (IR) thermography during cryosurgery for basal cell carcinomas (BCCs), evaluating the impact of adrenaline on thaw time. A total of 15 patients with eyelid BCCs underwent cryosurgery with local anaesthetics both with and without adrenaline. Thawing was continuously monitored using a high-resolution IR camera and compared with the surgeon's visual assessment. No significant difference in thaw time was observed between anaesthetics with and without adrenaline. Thermographic mapping revealed a triphasic thawing curve. The surgeon's visual assessment of thawing corresponded well with the point at which tissue temperatures rose above 0°C, likely indicating the onset of reperfusion, thus providing a clinical margin beyond the actual phase transition. This is the first study to use IR thermography to monitor cryosurgery of BCCs, demonstrating that adrenaline in local anaesthetics does not affect thaw time. The findings suggest that deeper tissue perfusion during BCC treatment may counteract superficial vasoconstriction, supporting the effective use of cryosurgery regardless of adrenaline use.