The Chimeric Gracilis and Profunda Artery Perforator Flap: Characterizing This Novel Flap Configuration with Angiography and a Cadaveric Model.

BACKGROUND: A chimerically configured gracilis and profunda artery perforator (PAP) flap is highly prevalent based on recent computed tomography (CT)-imaging data. The purpose of this study is to further characterize the vascular anatomy of this novel flap configuration and determine the feasibility of flap dissection. METHODS: To characterize flap arterial anatomy, lower extremity CT angiograms performed from 2011 to 2018 were retrospectively reviewed. To characterize venous anatomy and determine the feasibility of flap harvest, the lower extremities of cadavers were evaluated. RESULTS: A total of 974 lower extremity CT angiograms and 32 cadavers were included for the assessment. Of the 974 CT angiograms, majority (966, 99%) were bilateral studies, yielding a total of 1,940 lower extremities (right-lower-extremity = 970 and left-lower-extremity = 970) for radiographic evaluation. On CT angiography, a chimerically configured gracilis and PAP flap was found in 51% of patients (n = 494/974). By laterality, chimeric anatomy was present in 26% of right lower extremities (n = 254/970) and 25% of left lower extremities (n = 240/970); bilateral chimeric anatomy was found in 12% (n = 112/966) of patients. Average length of the common arterial pedicle feeding both gracilis and PAP flap perforasomes was 31.1 ± 16.5 mm (range = 2.0-95.0 mm) with an average diameter of 2.8 ± 0.7 mm (range = 1.3-8.8 mm).A total of 15 cadavers exhibited chimeric anatomy with intact, conjoined arteries and veins allowing for anatomical tracing from the profunda femoris to the distal branches within the tissues of the medial thigh. Dissection and isolation of the common pedicle and distal vessels was feasible with minimal disruption of adjacent tissues. Chimeric flap venous anatomy was favorable, with vena commitante adjacent to the common pedicle in all specimens. CONCLUSION: Dissection of a chimeric medial thigh flap consisting of both gracilis and PAP flap tissues is feasible in a cadaveric model. The vascular anatomy of this potential flap appears suitable for future utilization in a clinical setting.

Vismodegib Therapy for Basal Cell Carcinoma in an 8-Year-Old Chinese Boy with Xeroderma Pigmentosum.

Vismodegib is an oral inhibitor of the Hedgehog signaling pathway and has been used to treat basal cell carcinoma (BCC) in adults. This article reports clearance of a nodular BCC of the nasal tip in an 8-year-old boy with xeroderma pigmentosum (XP). BCC can pose therapeutic challenges when located in areas that are not amenable to traditional therapies such as Mohs micrographic surgery or topical agents. Vismodegib was used at a dose of 150 mg/day to treat the boy's BCC. After 4 months of therapy, we achieved complete clinical clearance. During 21 months of follow-up, the patient's nose remained clinically clear of tumor. Vismodegib was successfully used to treat a child with XP and nodular BCC. Our goal in using vismodegib was tumor regression while avoiding cosmetic and functional disfigurement. Vismodegib was effective in clinically clearing the tumor, and the patient has shown no signs of recurrence. Further studies are warranted.