BACKGROUND: The current gold standard for preoperative perforator mapping in breast reconstruction with a DIEP flap is CT angiography (CTA). Dynamic infrared thermography (DIRT) is an imaging method that does not require ionizing radiation or contrast injection. We evaluated if DIRT could be an alternative to CTA in perforator mapping. METHODS: Twenty-five patients scheduled for secondary breast reconstruction with a DIEP flap were included. Preoperatively, the lower abdomen was examined with hand-held Doppler, DIRT and CTA. Arterial Doppler sound locations were marked on the skin. DIRT examination involved rewarming of the abdominal skin after a mild cold challenge. The locations of hot spots on DIRT were compared with the arterial Doppler sound locations. The rate and pattern of rewarming of the hot spots were analyzed. Multiplanar CT reconstructions were used to see if hot spots were related to perforators on CTA. All flaps were based on the perforator selected with DIRT and the surgical outcome was analyzed. RESULTS: First appearing hot spots were always associated with arterial Doppler sounds and clearly visible perforators on CTA. The hot spots on DIRT images were always slightly laterally located in relation to the exit points of the associated perforators through the rectus abdominis fascia on CTA. Some periumbilical perforators were not associated with hot spots and showed communication with the superficial inferior epigastric vein on CTA. The selected perforators adequately perfused all flaps. CONCLUSION: This study confirms that perforators selected with DIRT have arterial Doppler sound, are clearly visible on CTA and provide adequate perfusion for DIEP breast reconstruction. TRIAL REGISTRATION: Retrospectively registered at ClinicalTrials.gov with identifier NCT02806518 .