The Color Duplex Ultrasound: The Reconstructive Surgeon's Stethoscope
Joon Pio Hong
Abstract
Over the years of reconstruction, the tools for diagnosis were limited for reconstructive microsurgeons. For decades, the main tools were the knowledge of anatomy, anecdotal experience, and good judgement. In the modern era, the angiogram and computed tomography (CT) angiograms played a key role in proving critical information of the vascular status.[1] With the introduction of handheld Doppler, it further brought understanding of small vessels like perforators, and the simplicity allowed it to be used not only preoperatively but help intraoperative decision-making and postoperative monitoring.[2] The handheld Doppler opened the doors to freestyle flaps where the flap can be designed around any perforator.[3] [4] Now the success rate for free flaps can be from 90 to 99%.[4] [5] Despite the high success rate, microsurgeons continues the endeavor to make flap reconstruction easier, replicable, reliable, and efficient. Thus new diagnostic evaluation tools are constantly being introduced to this field. The thermography and indocyanine green angiography are newly introduced tools that allow us to have better understanding for flap surgery. However, all tools have their pros and cons. When considering the cost, imaging speed, learning curve, perforator imaging, flow physiology, and depth of tissue information, one must determine which imaging modalities are able to provide the best information.[6] In my opinion, color duplex ultrasound (CDU) is a tool that is able to provide the most information with the highest efficiency. Early reports of using CDU have shown its efficacy and precision in identifying various anatomical structures including perforators.[7] [8] [9] Unfortunately, despite early reports, the CDU did not gain wide usage among reconstructive surgeons due to the lack of accessibility.