Smartphone Thermal Imaging for Preoperative Perforator Mapping in Perforator Based Flaps.

Objective: To determine the diagnostic accuracy of smartphone thermal imaging for preoperative perforator mapping in perforator-based flaps, taking visual inspection as gold standard.

Methodology: It was a cross-validation study conducted at the Department of Plastic Surgery, Dr. Ruth K. Pfau Civil Hospital, Karachi, Pakistan, from August 2022 to January 2023. All adult patients aged 18 to 40 years of either gender undergoing perforator flap surgery were included. Each patient followed the same treatment regimen, which involved the preoperative identification of the perforator location using the FLIR One camera. Subsequently, confirmation was achieved during the surgical procedure through visual inspection. A two-by two table was used to calculate sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy.

Results: The mean age of the patients was 30.10±6.87 years, ranging from 18 to 40 years. Most of the patients were males (58.7%), and 41.3% were females. Almost 80.4% were pedicle flaps, and 19.6% were free flaps. The accuracy of thermal imaging was found to be 83.2%, with a sensitivity of 84.3%, a specificity of 80%, a PPV of 92.9%, and a NPV of 62.2%, respectively.

Conclusion: Smartphone-based thermal imaging is useful for the diagnosis of perforators and has high sensitivity and specificity.