Intraoperative Use of Indocyanine Green Fluorescence Angiography during Distally Based Radial Artery Perforator Flap for Squamous Cell Carcinoma of the Thumb

Distally based radial artery perforator flap (DBRAPF) is useful for hand defects; however, the location of the perforator varies among individuals. Preoperative evaluation has been a problematic issue when performing this flap. A 64-year-old man developed squamous cell carcinoma on an old burn scar at the dorsal thumb and was referred to our clinic for further treatment. After wide resection of the tumor, including the long and short extensors of the thumb, we reconstructed the defect with DBRAPF. At that time, near-infrared fluorescence angiography with indocyanine green (ICG) was used to identify the position of the perforator. After injecting ICG intravenously, we could observe its uptake at approximately 5 cm proximal to the styloid process. We designed a 10 × 6 cm island flap with that uptake as pivot point. During flap elevation, the perforator could be confirmed at the point of uptake; the flap was then transferred to the defect by rotating the pedicle at the identified point. The vascularity of the flap could also be checked intraoperatively through ICG angiography. The tip of the flap that showed weak ICG fluorescence indicated epidermal necrosis. Nevertheless, the entire flap was viable and enabled good functionality without tumor recurrence and metastasis after 5 years. Using ICG angiography, DBRAPF could be performed smoothly, easily, and safely.