enlargement of the fourth brain ventricle, 3d

fourth ventricle hydrocephalus ventricular 3d cerebrospinal dilated enlarged enlargement ependymal aqueductal stenosis cyst head hypothalamic intraventricular malformations neurocytoma obstruct obstructive hamartoma congenital isolated illustration brain black background body disorders trapped diseases neurology tumor skeleton fluid size neurological anatomy cerebral pathology lateral hydrocephalic