PURPOSE: To evaluate the accuracy of multidetector computed tomographic (CT) angiography versus color Doppler ultrasonography (US) for perforating artery identification, intramuscular course of perforator vessel assessment, and superficial venous communication detection before a deep inferior epigastric perforator (DIEP) procedure for breast reconstruction. MATERIALS AND METHODS: Informed consent and institutional review board approval were obtained. Forty-five patients underwent multidetector CT angiography and color Doppler US to identify the DIEP vessel prior to breast reconstruction surgery. Findings at surgery were used as a reference for accuracy evaluations. RESULTS: The accuracy for identifying dominant perforator arteries was 97% for color Doppler US and 91% for CT angiography. Perforator arteries suitable for surgery were identified in 90% of cases with color Doppler US and in 95% of cases with CT angiography. For measurement of perforator calibers, surgical findings were similar to color Doppler US measurements (P = .33) but were significantly different than CT measurements (P < .0001). The accuracies for intramuscular course of perforator vessel assessment and superficial venous communication detection were 95% and 97% for CT and 84% and 80% for color Doppler US, respectively. In our population, the absence of superficial venous communication was associated with a risk for flap morbidity (P = .009). CONCLUSION: Both color Doppler US and CT angiography resulted in accurate DIEP mapping. Color Doppler US was superior for measuring perforator artery calibers, and CT angiography was superior for estimating the intramuscular course of the perforator vessel and identifying superficial venous communications. Considering x-ray exposure and results of this study, employing multidetector CT angiography is suggested only in selected cases.