Last Updated: March 25, 2020
The tentorial incisura provides the only communication between the supratentorial and infratentorial spaces (17) (Fig. 5.1). The area between the upper brainstem and the incisural edges is divided into the anterior, middle, and posterior incisural spaces (Fig. 5.2). The anterior incisural space is located anterior to the brainstem and extends upward around the optic chiasm to the subcallosal area; the middle incisural space is located lateral to th...