Abstract
Introduction Although numerous anatomical and operative atlases have been published, those that
have focused on the skull base either have provided views that are quite difficult
to achieve in the operating room to better depict surgical anatomy or are written
at the level of an audience with considerable knowledge and experience.
Methods Five sides of three formalin-fixed latex-injected specimens were dissected under
microscopic magnification. A posterior petrosectomy approach was performed by three
neurosurgical residents at different training levels with limited previous experience
in anatomical dissection mentored by the senior authors (C. L. W. D. and M. J. L.)
and a clinical skull base fellow with additional anatomical dissection experience
(M. P. C.). Anatomical dissections were performed until the expected level of dissection
quality was achieved to demonstrate each important step of the surgical approach that
would be understandable to all trainees of all levels. Following dissection education,
representative case applications were reviewed.
Results The posterior petrosectomy (also known as presigmoid retrolabyrinthine approach)
affords excellent access to cranial nerves III to XI and a diverse array of pathologies.
Key steps include positioning and skin incision, scalp and muscle flaps, burr holes,
craniotomy flap elevation, superficial mastoidectomy, otic capsule exposure and presigmoid
dura decompression, primary presigmoid durotomy, inferior temporal durotomy, superior
petrosal sinus ligation, tentorium sectioning, and final exposure.
Conclusion The posterior petrosectomy is a challenging approach; thorough operative-style laboratory
dissection is essential to provide trainees with a suitable guide. We describe a comprehensive
approach to learning this technique, intended to be understandable and usable by a
resident audience.
Keywords
posterior petrosectomy - meningioma - brainstem - skull base - education