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Preoperative vascular planning of free-based flaps. Comparative study between Computed Tomographic Angiography, Color Doppler Ultrasonography and Hand-Held Doppler.

BACKGROUND
Preoperative planning of microsurgical perforator free flaps continues to be a discussion topic between microsurgeons. The purpose of this study was to compare the ability of three methods of preoperative vascular mapping: Hand-held Doppler (HD), Color Doppler ultrasonography (US) and Computed Tomographic Angiography (CTA) to detect perforators and their concordance with surgical findings METHODS:: A prospective study was performed to evaluate the sensitivity, specificity, and accuracy of HD, US and CTA to detect free flap perforators. Each patient undergoing a free flap reconstruction was studied preoperatively with the three methods and the results were compared to the intra-operative findings.


RESULTS
Fifty-three patients undergoing autologous tissue reconstruction were included. Most reconstructions (71.7%) were performed with anterolateral thigh flaps. The positive predictive value (US 100%, CTA 100%, HD 88.6%) and negative predictive value (US 100%, CTA 94.3%, HD 90.5%) rates were significantly different between the three methods.The high resolution of the US probe provided a direct vision of the vasculature arborization and efficiently detected vessels with diameters of less than 0.5 mm efficiently. The sensitivity, specificity, and accuracy of the US were greater than those of both the CTA and HD. There was 100% concordance between US perforators and the surgical findings CONCLUSION:: US provides a reproducible, harmless and accurate way to visualize vascular anatomy. It has a high correlation with the surgical findings, signifying advantages over HD and CTA in sensitivity, specificity, and accuracy.