The Paramedian Supracerebellar Infratentorial Approach: 2-Dimensional Operative Video

The supracerebellar-infratentorial approach uses the plane between the tentorium and the superior surface of the cerebellum to expose the pineal region.

The bone opening is just underneath the level of the transverse sinus, and so its position must be noted preoperatively. The anatomy of the internal cerebral veins and the veins of Galen and Rosenthal should be examined as well.

The sitting position allows gravity-assisted expansion of the supracerebellar corridor, and a paramedian approach provides the biggest working space in the TIGER triangle, delineated by the tentorial surface of the cerebellum, the internal cerebral vein/Galen complex, and the vein of Rosenthal. The veil of arachnoid beyond the triangle must be carefully opened to expose the pineal region.

For the sitting position, the operative team must be careful about air emboli. A patent foramen ovale is a contraindication for the position. The deep veins must be handled delicately to avoid complications.

Several variations are shown in this video. For visualization, augmented reality is helpful, but since current augmented reality technology is microscope-based, its use can be ergonomically challenging if the tentorium is steep. 1 Our current preference is to use the exoscope for the major portion of the procedure until most of the tumor is out and then switch to hand-held endoscopes with various angles to finish the operation.The patients consented to the surgery, and all relevant participants consented to publication of their images.