There are correlative differences in the anterior third: the veins vary in importance, sometimes forming an anterior collateral pathway draining into the Sylvian fissure; the prefrontal cortex may be considered less eloquent than other areas; a safer resectable sinus lying at the beginning of the venous system. Also, there are differences in the middle third: important and florid bridging veins, in addition to the sinus and the presence of the motor strip.

see Parasagittal sinus meningioma of the posterior third