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Converting a previous fasciocutaneous free flap into a flow‐through flap for scalp reconstruction

A 76-year-old male, diagnosed with a poorly differentiated scalp squamous cell carcinoma, was managed with excision, splitthickness skin graft (SSG) reconstruction and adjuvant radiotherapy. Subsequent development of an atypical fibroxanthoma in the grafted region within the irradiated field was excised and re-grafted. A scalp rotation flap was employed following graft failure, however, distal flap necrosis ensued. Bone burring and biodegradable temporizing matrix with subsequent SSG failed, leaving exposed osteoradionecrotic calvarium. Craniectomy and titanium mesh cranioplasty with latissimus dorsi (LD) free flap reconstruction anastomosed to the left superficial temporal artery were performed. Histopathology revealed no residual tumour. Three weeks post procedure, partial necrosis at the distal aspect of the LD flap was identified. Debridement was undertaken with further local transposition flap coverage. Again, serial debridement was required and a left radial forearm free flap (RFFF) was required to cover the exposed bone and metalware, with recipient artery being the right superficial temporal artery. The post-operative course was complicated with a clear sterile discharge from the wound and progressive shrinkage and nonadherence of the RFFF. The cranioplasty was removed, leaving a 5 × 5 cm defect with exposed dura. Dissection of the intra-flap pedicle of the RFFF as a recipient was undertaken 3 months after it was placed because local reconstructive flap options were unavailable and suitable recipient native donor pedicles absent. A free vertical rectus abdominus muscle flap was selected. End-to-end arterial coaptation was performed, as well venous coupled deep inferior epigastric artery venae comitantes to both the cephalic vein and a large superficial tributary in the RFFF, 2.5 and 1.5 mm calibre, respectively. The anterior aspect of the flap was inset to native scalp skin, with SSG used to cover the posterior myofascial component. The reconstruction healed well, with no compromise to the vascularity of the remaining portions of his prior free tissue reconstructions (Fig. 1). Microvascular recipient vessel selection can be a complex problem faced by the reconstructive microsurgeon. This case describes a complex serially reconstructed irradiated scalp defect where a previous fasciocutaneous free flap pedicle was converted into a flowthrough flap to provide an additional recipient vascular pedicle. Complex scalp reconstructions requiring multiple free tissue transfers have been reported. Hussussian and Reece describe their experience, highlighting that almost one-third of their free flap reconstructions were undertaken after failed reconstructive endeavours, and that some patients required a second free flap. They described high complication and reoperation rates, especially following radiotherapy. Various recipient blood vessels, including the original flap vessels in an end-to-end fashion were described. We are unable to determine if they dissected out an intra-flap pedicle in the manner that we have performed, or simply used the previous recipient vessel. Multiple free flaps and chimeric flaps may be used in a single stage, such as the use of bilateral anterolateral thigh (ALT) free flaps, bilateral LD flaps or combined LD and serratus anterior flaps. Published complex reconstructive cases describe the need for dual free flap reconstructions, or even three sequential microvascular transfers. Ikander and Sørensen present a patient with radiorecurrent squamous cell carcinoma of the scalp requiring three separate free flap reconstructions. Two LD flaps and an ALT flap were used serially, resulting in partial flap loss and tumour recurrence. Similarly, Wang et al. describe the complex management of a patient with serial free flaps including two RFFF and an ALT flap. In these examples, flaps were able to be anastomosed to native vessels, rather than the added challenge of a tertiary reconstruction with no available local recipient. Flow-through flaps in head and neck surgery is not a new concept, with the merits first described in 1983. There are accounts of utilizing free flaps with flow through for scalp reconstruction;