1989 Volume 66 Issue 2-3 Pages 81-97
The distribution and structure of the arachnoid granulations and villi in the region of the sella turcica in human adult brains were observed under light microscopy. In order to study the interrelationships between the arachnoid projections, hypophysis, cavernous sinus, and sella turcica, we performed a three-dimensional reconstruction and analysis of the region with the use of a digital image-processing method. Arachnoid projections penetrating the dura were villous when they were few in number, but more frequently granular when they were numerous. No relationship was observed between the type of projections and the age or the underlying disease of the subjects. Brains which showed no or few arachnoid granulations or villi had a small and deep hypophyseal fossa with a poorly-developed intercavernous sinus or venous plexus. Three-dimensional image analysis revealed that arachnoid granulations and villi form a maze in the dura or connective tissue between the venous plexuses.