Location was analyzed with respect to outcome (GOS) by dividing the patients into 3 groups according to the level of technical difficulty posed by the tumor location (based on a review of 800 operative cases, personal series):
Simple: Convexity, lateral sphenoid wing, cerebellar convexity, posterior petrous, posterolateral foramen magnum
Moderate: Falx, parasagittal, middle sphenoid wing, olfactory groove, lateral tentorial, Transverse/sigmoid sinus
Complex: Anterior clinoid, tuberculum sella, cavernous sinus, petroclival, ventral petrous, medial tentorial, dorsal clinoid, pineal, ventral foramen magnum
No death was encountered in the “Simple” location group, and the overall incidence of excellent outcome (GOS 4 & 5) can be seen to be decreasing in a step-wise fashion going from the “Simple” to “Moderate” locations, then going from the “Moderate” locations to the “Complex” locations.
In summary, patients with meningiomas in “simple” locations do very well following surgery compared to those with tumors in more difficult or “complex” locations. Location does matter in determining the outcome following meningioma surgery.