Anatomical Step-by-Step Dissection of Complex Skull Base Approaches for Trainees: Surgical Anatomy of the Frontotemporal and Orbitozygomatic Craniotomies

Introduction: Numerous neuroanatomic atlases and visual texts have been published highlighting the complex neurovascular anatomy of the skull base; however, few detailed step-wise surgical approach anatomy and considerations compiled for the resident level and beyond.

Methods: Five sides of formalin-fixed latex-injected specimens were dissected under microscopic magnification. The frontotemporal and orbitozygomatic approaches were performed by neurosurgical residents and fellows at different training levels with limited previous experience in anatomical dissection mentored by the senior authors (Maria Peria-Celda, MD, PhD, and Michael J. Link, MD). Meticulous surgical anatomic dissections were performed until sufficient visual and technical completion was attained, with parameters of effectively demonstrating key surgical steps for educational training purposes. Following completion of dissection and three-dimensional photography, representative pertinent cases were selected that underscored the suitability of the two approaches and nuances discussion was entertained.

Results: The frontotemporal and orbitozygomatic approaches afford excellent access to a myriad of anterior skull base pathology. Key steps and important surgical nuances and approach distinctions related to head positioning, skin incision and scalp retraction, fat pad dissection and facial nerve protection, true or false MacCarty key hole, sphenoid wing drilling and anterior clinoidectomy, completion of the craniotomy and accessory orbital osteotomy cuts, dural opening, and intradural neurovascular access.

Conclusion: The frontotemporal and orbitozygomatic approach provide distinct approaches for numerous complex neurovascular, with important approach-specific considerations that are important for trainees to complete these techniques safety and efficiently. The orbitozygomatic approach is a challenging approach; thorough operative-style laboratory dissection is essential to provide trainees with a suitable guide. We describe these approaches, and highlight their differences, with thorough three-dimensional images to provide unique surgical views that are accessible for neurosurgical trainees and advanced practitioners.

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Publication History

Article published online:
15 February 2022