Introduction: The anterior interhemispheric approach and its variants provide access to the anterior circulation, the suprasellar area, and/or the anterior third ventricle. We investigate the feasibility of a 3D-endoscope assisted anterior interhemispheric approach through a minimally invasive tubular retractor system for the management of anterior third ventricular lesions, anterior communicating artery aneurysms, and planum sphenoidale lesions.
Methods: Anterior interhemispheric approaches with superior, middle, and inferior variants were performed on 5 preserved cadaveric heads (10 sides) injected with colored latex. A ViewSite™ Brain Access System (Vycor Medical, Inc., Boca Raton, FL, USA) of tubular retractors was used. 2 to 3 cm burr holes were fashioned for each specimen with the aid of neuronavigation (Brainlab AG, Feldkirchen, Germany). The tubular retractor was introduced under direct 3D endoscopic visualization. Following observation of crucial neurovascular structures, dissection through the retractor was performed using bayonetted micro-instruments. Surgical exposure and maneuverability were qualitatively evaluated for each approach by 3 surgeons using a scoring system.
Results: This approach provided full exposure of the anterior circle of Willis and the anterior third ventricle with minimal retraction of the frontal lobes and anterior cerebral arteries. The tubular retractor enabled adequate anatomical visualization and provided stable frontal lobe retraction. Byonetted instruments and bipolar cautery were passed through the tubular retractor without difficulty, and the tubular retractor applied rigid, constant, and equally distributed pressure onto the impacted surfaces. The technique facilitated dissection of the anterior circulation and would permit clipping of anterior communicating artery aneurysms and adequate control of the planum sphenoidale.
Conclusions: An endoscope-assisted transtubular approach to this region is both safe and effective for the management of anterior communicating artery aneurysms and lesions of the anterior third ventricles and planum sphenoidale. Further clinical studies are necessary to determine potential clinical complications.
Patient Care: This approach provides full exposure of the anterior circle of Willis and the anterior third ventricle with reduced retraction of the frontal lobes and anterior cerebral arteries and may decrease the possibility of retraction injury.
Learning Objectives: By the conclusion of this session, participants should be able to describe the transtubular anterior interhemispheric approach.