Cadaveric comparison of two facial flap-harvesting techniques for alloplastic facial transplantation.

摘要

BACKGROUND: Functional and aesthetic reconstruction of severe facial deformities presents a major challenge, and the results are rarely satisfactory. Recent clinical success of composite tissue allograft transplantation and improvements in autoimmune regulation have initiated efforts to reconstruct severe facial deformities with alloplastic tissue. Few reports address the full facial flap dissection approach, where lengthy procedural times remain a limiting factor in achieving optimal graft survival. Extensive vascular anastomoses within facial tissues provide a unique opportunity to explore alternative graft harvesting strategies to optimise operative ischaemia. OBJECTIVE: The aim of the study was to shorten donor-graft harvesting time and reduce warm ischaemia. We evaluated alternative facial harvesting strategies through mock cadaveric facial transplantations. METHODS: Cadaveric dissections were performed to explore facial-scalp reconstruction alternatives. Six paired sub-superficial muscloaponeurotic system (SMAS) plane composite facial-scalp flaps were harvested using either a superficial temporal artery (STA) or a facial artery (FA) pedicle technique (Group I) or an external carotid artery (ECA) pedicle technique. Total harvesting times and lengths of vascular pedicles were measured. RESULTS: Harvesting time for a STA and FA pedicle total facial flap (mean=113min, range=105-120min, SD=6min) was shorter than that for an ECA pedicle flap (mean=232min, range=225-240min, SD=6min) (P<0.01). Mean pedicle lengths for the STA, the FA, the ECA, the external jugular vein, and the facial vein were 37+/-2.1, 35+/-1.8, 26+/-1.4, 52+/-3.0 and 42+/-2.6mm, respectively. Mean pedicle lengths for the supraorbital, supratrochlear, infraorbital, mental, and facial nerve were 15+/-1.5, 14+/-1.4, 24+/-1.2, 30+/-1.6 and 32+/-1.8mm, respectively. CONCLUSION: Compared with previously reported ECA pedicle total facial allograft harvesting techniques, an STA and FA pedicle flap provides a shorter harvesting timeand potentially safer dissection method for facial transplantation by avoiding interference with the complicated anatomy of the carotid and submental triangle. Early graft ischaemic damage can be minimised by this harvesting technique, which significantly shortens harvesting time compared with previously described approaches, while maintaining adequate full facial perfusion.