Reconstruction with an Endoscopic Temporalis Muscle Flap following Transorbital Endoscopic Skull Base Surgery Defects: Keeping It Minimally Invasive

Introduction: Transorbital endoscopic skull base surgery (TOES) has gained popularity in the preceding years and is being used more frequently as a minimally invasive approach for the management of intracranial and extracranial skull base lesions. With its expanding indications, TOES has the potential to create considerable skull base defects. In light of this, given the inability to use routine reconstructive options available during endonasal surgery (e.g., nasoseptal flap), readily available alternatives must be sought for these types of defects. The temporalis muscle flap (TMF) has been used for the reconstruction of various areas of the skull base including orbital and middle fossa floor defects given its proximity to these areas. Although useful, it requires a large skin incision for harvest which presents a limitation to its use during minimally invasive TOES. The objective of this study is to present a minimally invasive technique for the harvest of a TMF for the reconstruction of skull base defects following TOES.

Methods: Following transorbital exposure of the infratemporal fossa performed through a lateral canthal incision a TMF was harvested.

Results: Taking advantage of the lateral canthal incision, the lateral orbital rim was exposed and the temporalis fascia adhering to its posterior border was identified and transected to identify the temporalis muscle. Endoscopic dissection was performed deep to the temporalis fascia along the entirety of the muscle posteriorly to the root of the zygoma and superiorly to the superior temporal line. Once the temporalis fascia was separated from the muscle, subperiosteal dissection was performed over the zygoma to subsequently transect the deep temporalis fascia and release the temporalis muscle laterally. Subperiosteal dissection was performed to release the cranial attachments of the temporalis muscle. The muscle was released along its superior insertion to the superior temporal line and was transposed into infratemporal fossa trough the lateral orbital defect created with the transorbital approach. In a similar fashion the same was done for reconstruction of a middle fossa floor defect following Meckel's cave exposure. The temporalis flap was inset appropriately with no tension and no difficulty.

Conclusion: Endoscopic harvest of a TMF provides a useful and novel approach for reconstruction of skull base defects following TOES.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
12 February 2021