The extended supracerebellar transtentorial approach for resection of medial tentorial meningiomas
A 43-year-old male presented with several months of progressive dysarthria and gait imbalance. Imaging work-up including magnetic resonance imaging (MRI) demonstrated a large left medial tentorial meningioma extending along the posteromedial aspect of the temporal lobe and medial aspect of the brainstem, causing significant mass effect on these structures with early signs of hydrocephalus []. Large flow-voids within the tumor emphasized its rich vascularity [].\nFollowing modest embolization of the tumor's large feeding meningeal vessels, resection was attempted. A staged procedure for the infratentorial and supratentorial components of this tumor was considered. We decided that a SCTT route would avoid a staged operation and minimize the risk to the dominant temporal lobe. Using a paramedian incision [], we attempted a SCTT approach with skeletonization of the transverse and sigmoid sinuses. After devascularization of the tumor's base along the tentorium, the tumor's infratentorial component was removed while preserving the trochlear nerve and surrounding vasculature [].\nUsing the technique mentioned above, we incised a section of the tentorium affected by the tumor and removed the supratentorial extension of the tumor as well as the piece attached to the petrous apex. This operative corridor allowed microsurgical dissection of the tumor wall away from the cortex and adjacent distal PCA branches. A small portion of the tumor lateral and superior to the petrous apex was left behind due to its inaccessibility []. This case underlines the supratentorial limits of this approach, unless petrous apex bony drilling is attempted through the posterior fossa. Pathological examination found a World Health Organization (WHO) grade I meningioma. The patient recovered from surgery with no deficits. All his preoperative symptoms had resolved at 3-month follow-up. At the 4-year follow-up, MRI did not demonstrate any growth of the residual tumor.