Introduction: The perisellar region is the anatomical area which surrounds the sella and houses the highest concentration of neurovascular structures in the middle cranial fossa, including upper cavernous sinus, planum sphenoidale, and interpeduncular fossa. We analyze and compare surgical approaches to each defined anatomical compartment and discuss the relative advantages of the microsurgical approaches to the perisellar region.
Methods: Ten perisellar regions were evaluated in 5 cadaveric heads through supraorbital, bilateral subfrontal, unilateral subfrontal, modified orbitozygomatic, pterional, and subtemporal craniotomies. The adequacy of the extent of the various surgical approaches was evaluated in detail, with emphasis on the degree of perisellar exposure and brain retraction required. Additionally, we evaluated the exposure provided by 0°, 30°, and 45° endoscopes.
Results: We categorized the skull base approaches to the perisellar area by subdividing this region into anatomical quadrants according to 6 anatomical planes: 3 coronal (posterior, middle, and anterior), 3 sagittal (left, middle, right), and 1 axial. The anterior coronal plane passes through the tuberculum sellae and the posterior coronal plane passes through the posterior clinoid processes. The 2 sagittal planes pass on each side of the sella by the tuberculm anteriorly and the posterior clinoid process posteriorly. The axial plane passes through the diaprahma sellae. As a result, we divided the perisellar region into 2 anterior compartments (left and right), 2 lateral compartments on each side (anterior and posterior), and one posterior (left and right). These compartments were all subdivided into superior and inferior by an axial plane passing at the level of the diaphrama sellae. The anatomical relationships of each sub-compartment was studied and discussed in detail. We finally analyzed and compared available surgical approaches to each single sub-compartment.
Conclusions: A clear understanding of the anatomy of the perisellar region is essential in the planning and safe execution of the various microsurgical approaches.
Patient Care: We anticipate the impact of this anatomical and microsurgical study of the perisellar region to be far-reaching. This in-depth study is the first of it’s kind to clearly delineate the perisellar anatomy and correlate this with microsurgical approaches, and the use of endoscopic visualization as an adjunct.
The perisellar region houses the highest density of neuro-vascular structures with critical neural, osteological and vascular relationships, and hence has a myriad of associated pathologies and neurological deficits.
We have aimed to clarify the complex anatomy of the perisellar region by further dividing this into sub-compartments. We have further identified how the various approaches to the parasellar region must ensure maximum visualization of the perisellar subcompartment of interest, with minimal brain retraction thus minimizing patient morbidity.
Learning Objectives: By the conclusion of this session, participants should be able to
1) Describe the sub-compartments and anatomical relationships of the peri-sellar region
2) Discuss the various microsurgical approaches to the perisellar region, with discussion of the merits of each approach.
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