Preoperative detection of perforating vessels in autologous abdominal flap-based breast reconstruction using a smartphone-based thermography device

Abdominal-based microvascular perforator flaps remain the technique of choice in autologous breast reconstruction. Preoperative identification of the morphology, localization, and course of perforating vessels is of utmost importance. Various imaging modalities are currently used, including duplex sonography, computed tomography angiography, and magnetic resonance angiography. Thermography displays temperature variations on the skin surface and may help identify hotspots using a smartphone-based, handheld, low-cost device. This cross-sectional observational study evaluated such a thermography device and compared its accuracy with computed tomography and magnetic resonance angiography. Sixty patients undergoing abdominal tissue-based breast reconstruction between 2019 and 2022 were included. Preoperative skin perfusion was assessed using the device after cooling the abdominal skin with soaked towels at approximately 17 °C for five minutes, followed by spontaneous rewarming to room temperature. Thermographic images were taken at defined intervals. Hotspots were defined as the hottest 1 cm diameter areas on the skin surface. In patients with subcutaneous tissue thickness below 30 mm, hotspots at 3 min after cooling correlated with radiologically identified perforators in 42 percent of cases. In patients with thickness above 30 mm, the highest correlation (43 percent) was observed at 30 min. Across all timepoints, correlation ranged from 0 to 75 percent. Smartphone-based thermography provides a quick, non-invasive method to identify hotspots on the skin surface. However, correlation with computed tomography or magnetic resonance angiography was below 50 percent and highly dependent on subcutaneous thickness. As it does not show vessel caliber or intramuscular course, thermography cannot replace standard imaging but may serve as an adjunct.