fig 3.

Fixed brain. A, Coronal section shows elevation of the fornices and obstruction of the interventricular foramina of Monro by the colloid cyst (arrows). Bilateral multifocal acute hemorrhages are seen in the periventricular white matter. A hemorrhagic infarction in the left basal ganglia is seen.

B, Cut surface of colloid cyst displays turbid, gelatinous material. The fornices are lifted and the third ventricle is expanded.

C, Drawing of coronal view shows forniceal columns stradding the colloid cyst wedged in the roof of the third venticle. Note herniation of the left uncus and compression of the contralateral cerebral peduncle against the free edge of the tentorium, causing hemorrhage in the right midbrain.