Lengthening the nasoseptal flap pedicle with extended dissection into the pterygopalatine fossa.

Objectives/hypothesis: Releasing the nasoseptal flap (NSF) pedicle from the sphenopalatine artery (SPA) foramen may considerably improve flap reach and surface area. Our objectives were quantify increases in pedicle length and NSF reach through extended pedicle dissection into the pterygopalatine fossa (PPF) through cadaveric dissections and present clinical applications.

Study Design: Anatomical study and retrospective clinical cohort study.

Methods: Twelve cadaveric dissections were performed. Following standard NSF harvest, the distance from the anterior edge of the flap to the anterior nasal spine while pulling the flap anteriorly was measured. As dissection into the SPA foramen and PPF continued, similar interval measurements were completed in four stages after release from the SPA foramen, release of the internal maxillary artery (IMAX), and transection of the descending palatine artery (DPA). The extended pedicle dissection technique was performed in seven consecutive patients for a variety of different pathologies.

Results: The mean length of the NSF from the anterior nasal spine and maximum flap reach were 1.91 ± 0.40 cm/9.3 ± 0.39 cm following standard harvest, 2.52 ± 0.61 cm/9.75±1.06 cm following SPA foramen release, 4.93 ± 0.89 cm/12.16 ± 0.54 cm following full IMAX dissection, and 6.18 ± 0.68 cm/13.41 ± 0.75 cm following DPA transection. No flap dehiscence or necrosis was observed in all seven surgical patients.

Conclusions: Extended pedicle dissection of the NSF to the SPA/IMAX markedly improves the potential length and reach of the flap. This technique may provide a feasible option for reconstruction of large anterior skull base and craniocervical junction defects. Seven successful cases are presented here, but further studies with larger series are warranted to validate findings in a clinical setting.

Level Of Evidence: 4 Laryngoscope, 130:18-24, 2020.