Exploring Alternative Flaps in Endoscopic Skull Base Repair: A Comparative Cadaveric Study between Inferior Turbinate and Nasoseptal Flaps

Abstract

Introduction Over the past several decades expanded endonasal approaches have advanced significantly, paralleling the increasing importance of skull base defect reconstruction. The nasoseptal flap (NSF) is first line for most skull base reconstruction but may fail for complex or recurrent cerebrospinal fluid (CSF) leaks in central skull base. The inferior turbinate flap (ITF) presents an alternative due to proximity and robust vascular supply. This cadaveric study compares the NSF and ITF in central skull base repairs, detailing indications, limitations, and dimensions.

Methods We analyzed five cadaveric head specimens provided by the Medical College of Georgia Department of Anatomy. The NSF and ITF were raised bilaterally on each head, yielding 20 flaps in total. Length and width of each flap were measured, and total coverage area was calculated. SPSS (ver.20.0) was used for statistical analysis. Differences in mean width, length, and coverage area between the NSF and ITF were analyzed using Student's two-independent sample t-test, with p-values <0.05 considered statistically significant.

Results The NSF was significantly longer (64.6 mm) than ITF (42.8 mm), but the ITF was wider (46.6 mm) than NSF (36.5 mm). NSF had a larger mean coverage area (23.6 cm²) than ITF (19.9 cm²) (p = 0.053).

Conclusion While the NSF provides superior coverage, the ITF is a viable option in the reconstruction ladder for central skull base defects when NSF fails, offering advantages in terms of proximity, vascular supply, and lower morbidity over other rescue flaps. Surgical technique in harvesting this flap should be known to any skull base surgeon over other more complex reconstruction flaps.

Keywords

skull base reconstruction - nasoseptal - inferior turbinate - flaps - grafts - cerebrospinal fluid leak

Publikationsverlauf

Eingereicht: 23. Juli 2024

Angenommen: 05. Januar 2025

Artikel online veröffentlicht:
11. Februar 2025

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