Accessing the Third Ventricle Using a Novel 3D Endoscope-Assisted Transtubular Transcallosal Approach

Objective: In certain cases, the transcallosal approach remains the best option for targeting lesions of the third ventricle, though retraction of the fornices and wall of the third ventricle have been associated with neuropsychological and hypothalamic deficits. We investigate the feasibility of an interhemispheric 3D endoscope-assisted transcallosal approach through a minimally invasive tubular retractor for accessing third ventricular lesions. Study Design, Material, and Methods: Transtubular transcallosal approaches were performed in five preserved cadaveric heads (10 sides). A ViewSite Brain Access System (Vycor Medical, Inc., Boca Raton, Florida, United States) of tubular retractors was used. A parasagittal burr hole was placed and a tubular retractor was introduced. Fenestration of the corpus callosum was performed and the retractor was advanced through the opening. Transforaminal, interforniceal, and trasnchoroidal modifications were all performed and qualitatively evaluated and scored. Results: This approach provided enhanced visualization of third ventricle and more stable and rigid retraction of corpus callosum and fornices. The tubular retractors applied rigid, constant, and equally distributed pressure. This technique may also allow for the splitting of white matter tracts rather than their transection. Conclusion: This is a feasible approach for the management of intraventricular pathologies and provides an added degree of safety by limiting the free range of instrumental movement.