Infrared thermal imaging as a non-invasive predictive tool for early detection of flap necrosis after breast cancer surgery: A prospective cohort study.

[BACKGROUND] Skin flap necrosis is a common complication after breast cancer surgery, affecting postoperative recovery and subsequent treatment. Current assessment methods are often subjective or expensive. This study explored the use of infrared thermal imaging (IRT) for early, non-invasive, and real-time prediction of skin flap necrosis.

[METHOD] A total of 203 breast cancer patients were followed for five days after surgery. Skin temperature was measured daily using a portable infrared camera. The temperature difference (ΔT) between the skin flap and a control area was calculated. Receiver operating characteristic curves were used to evaluate the predictive performance of IRT. Kaplan-Meier analysis and Cox proportional hazards regression were applied to assess the association between skin temperature and the risk of skin flap necrosis. A joint prediction model incorporating clinical baseline variables and temperature indicators was visualized using nomograms.

[RESULTS] The incidence of skin flap necrosis was 10.84 %. ΔT was significantly associated with the risk of necrosis, with the strongest predictive value observed on postoperative day 5. A ΔT ≥ 0.7 °C was identified as a key indicator. The high-risk group had a 7.6 - fold higher risk of necrosis than the low-risk group. Age, nulliparity, smoking, and tumor pathology were independent risk factors. Incorporation of postoperative flap temperature indicators significantly improved the predictive performance of the model.

[CONCLUSION] IRT provides a non-contact method for assessing postoperative skin flap blood flow and metabolism. ΔT, particularly on postoperative days 4 and 5, is a significant predictor of skin flap necrosis risk.