Purpose: To demonstrate the usefulness of color Doppler ultrasound (CDU) in identifying perforators, the survival rate of flaps with perforators that were solely inspected by CDU was studied while evaluating data obtained by CDU.
Methods: Twenty one patients scheduled for perforator flap surgery from 2004 to 2012 were examined preoperatively by the author solely by CDU to detect perforators. From the penetrating point to the skin end, the entire length was included in the design. Studying the survival rate of the flaps, data including peak systolic velocity (PSV), resistance index (RI), acceleration time (AT), and diameter of perforators were evaluated. Horizontal length of the perforator was calculated by dividing the depth by the tangent of angle at which the perforator intersected with the horizontal plane.
Result: All of the flaps survived completely. The perforators detected by CDU coincided with the actual perforators. The lowest PSV was 7.2cm/sec and all the results of AT were normal. The values of RI were more than 0.7 in 13/16 cases, which indicates that modification of normal values is needed. The longest horizontal length was 5.7cm leaving a possibility of false positive by Doppler flowmetry in detecting the penetrating point of the deep fascia.
Conclusions: Color Doppler ultrasound is very useful in designing perforator flaps and provides an opportunity to rate the perforators. It might be safe to choose a perforator with a PSV is more than 8cm/sec and AT less than 0.1s. The normal value of RI needs to be modified.
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