Endoscope-Assisted Transmaxillosphenoidal Approach to the Sellar and Parasellar Regions: An Anatomic Study

Background Anterolateral skull base surgery in the sellar and parasellar regions has always represented a technical challenge for neurosurgeons. The microscopic endoscope-assisted transmaxillosphenoidal approach (MEMSA) affords a direct surgical corridor free from critical skull base structures. Here we describe and critically evaluate the use of MEMSA to access the sellar and parasellar areas, in terms of surgical exposure and operability. Methods Six cadaveric heads were examined. A stepwise dissection using MEMSA was performed. Relevant anatomy and surgical technique were critically described and comparatively reviewed. The operability score was applied for quantitative analysis of surgical operability. Results MEMSA provides wide bilateral surgical exposure and vascular control of the sellar, suprasellar, and parasellar regions, achieving the highest operability on the midline and in the parasellar region. The approach can be tailored to the lesion, with the surgical corridor easily widened toward the contralateral pterygopalatine fossa. Anatomic knowledge of maxillary sinus landmarks is key to the use of this approach. Favorable sphenoidal anatomy is the main limiting factor, making MEMSA a surgical alternative to endoscopic endonasal routes in situations where those routes are not feasible, and the approach of choice in selected cases of primarily sellar lesions widely extending contralaterally to the approached maxillary sinus. Conclusions MEMSA is a safe and effective technique that provides access to the sellar, suprasellar, and contralateral parasellar areas via a direct, minimally disruptive surgical corridor. The preservation of nasal anatomy ensures the availability of mucosal flaps for use in further reconstruction.