Viability of the temporoparietal fascia flap in closure of skull base defects. a radioanatomical study.

Purpose: The aim of this study is to evaluate the feasibility of using the temporopartietal fascia flap (TPFF) to close defects in the skull base through a radioanatomical study in cadaver.

Methods: A radioanatomical study was performed, bilaterally, in 5 cryopreserved human heads. Transposition of the TPFF was also performed via the infratemporal fossa after an endoscopic approach.

Results: The measurements of the flap resulted on an average of 124.2 mm in length and 51.8 mm in width at its distal end. The average area was 4323 mm². The study of the correlation between these measurements and skull base defects demonstrated that the flap is valid for the reconstruction of both cribriform plates, ethmoidal roof, sphenoidal planum and posterior wall of the frontal in all the samples. However, for the reconstruction of defects in approaches to the sellar region, only an 88.8% coverage has been achieved. In the closure of posterior fossa defects, such as clivus, we have managed to cover 55.5% of the defect in our samples.

Conclusions: The transposition of the TPFF is viable for the closure of defects in the skull base. Its main indication would be to cover anterior defects. In the case of approaches that aim to cover posterior defects, it may be necessary to increase the length of the flap with the pericranium or even with the contralateral temporoparietal fascia. The use of the temporoparietal flap without total resection of the pterygoid process is feasible.