A histological study of cerebral aqueduct

Cerebral (sylvian) aqueduct is a narrow channel in the mesencephalon. It lies between the tectum and the tegmentum of the mesencephalon and is surrounded by the periaqueductal gray matter. The aim of this study was to determine the shape of the aqueduct of sylvius and the structure of its walls in a series of transverse histological sections. Serial transverse sections of the mesencephalon were examined in twenty adult brains of both sexes. Six sections were stained by the hematoxylin-eosin method. The rostral part of the the aqueduct has a triangular shape with dorsal concavity caused by retrocommissural fossae. In the middle, its shape is oval to irregular, the rostral part has a T shape due to isthmic recess on the floor. Walls of the aqueduct are coated with a layer of prismatic cells. Determination of the morphological and histological features of the mesencephalic aqueduct is important for differentiation between physiological and pathological processes in this region.