Inferior Turbinate Pedicle Flap for Endoscopic Skull Base Defect Repair

Abstract

Endoscopic skull base reconstruction (ESBR) is an important advance in the management of skull base defects. Large dural defects usually require the use of pedicled mucosal flaps for successful repair and prevention of cerebral spinal fluid leak. Planning for pedicled flaps is important because raising the flap is often required before tumor removal or initial surgical access. The potential utility of the inferior turbinate pedicled flap (ITPF) in ESBR is assessed. The ITPF was raised in nine cadaver heads. The most anterior extent reached on the anterior cranial fossa (ACF) and inferior limit on the posterior cranial fossa (PCF) were recorded with image-guided surgery. Measurements were calculated as a percentage of ACF or PCF length from easily reproducible measurements from preoperative radiology. The width was defined as the widest measurement in the distal third. The length-to-height ratio of the skull base was also assessed as a confounding factor. Mean length for the ITPF was 54.0+/-4.9 mm with a width of 22.1+/-3.7 mm. The mean reach was 112+/-21% (range, 90-150%) of the PCF. The ACF was less accessible with a mean reach of 67+/-9.9% (range, 52-84%). The skull base proportions did not have a strong association on utility (p=0.74 and 0.29). ITPF presents one option for ESBR of larger skull base defects. It has several limitations with access to the anterior ACF. The ITPF may be an excellent salvage flap when previous septectomy has been performed or with septal involvement by tumor. Careful preoperative assessment of potential defect can estimate the reach of the ITPF.