3D Microsurgical and Endoscopic Anatomy of Different Surgical Approaches to the Interpeduncular Fossa and Dorsum Sellae: A Cadaveric Study

Introduction: The interpeduncular fossa region remains one of the most difficult areas to access surgically. Here, we objectively evaluate the exposure of the anatomic areas of the interpeduncular fossa and dorsum sellae, exposed by different surgical approaches, and assess the benefits of using a 3D endoscope.

Methods: The pterional approach (with and without anterior and posterior clinoidectomies), subtemporal approach, orbitozygomatic approach (with and without removal of the anterior and posterior clinoid processes and with the pericavernous modification), and the frontal transbasal approach were each performed three times on a total of 20 preserved cadaveric heads. Each anatomic compartment was explored using both a microscope and a 3D endoscope. A thorough assessment of surgical exposure was performed by multiple surgeons. The relationships between the different anatomical structures were carefully noted and their exposure assessed by approach.

Results: Use of the 3D endoscope allowed for a better understanding of the depth of the surgical field and of the relationships between the neurovascular complexes. The use of the 3D endoscope enhanced the subtemporal, frontal transbasal, and orbitozygomatic with pericavernous modification approaches. Conversely, the narrow surgical corridors provided by the pterional and orbitozygomatic approach without pericavernous work didn’t offer the same surgical maneuverability. The 3D endoscope also afforded better circumferential visualization of the neurovascular structures at the uppermost aspect of the fossa and at the region immediately above the dorsum sellae, as well as good contralateral control of the area.

Conclusion: We objectively evaluated the exposure of the interpeduncular fossa and dorsum sellae region afforded by each of the most suitable surgical avenues to access this region, using the microscope and the 3D endoscope, highlighting the differences among the multiple approaches. Although use of the 3D endoscope improves visualization, surgical maneuverability is still limited due to the size of the probe in relation to the constricted surgical corridors.