Fig. 12

Midsagittal 3D-DRIVE showing the aqueduct of Sylvius and third ventricular anatomy in a normal infant (a) and patients with aqueduct stenosis (b–d). a A normal third ventricle of a 1-year-old girl. The lamina terminalis and tuber cinereum are concave centrally which may suggest that the mean pressure in the third ventricle may be lower than that in the cisterns. Note the signal void within the patent aqueduct of Sylvius. b MRI of a 3-month-old with mild hydrocephalus showing dilatation of the third ventricle recesses with bulge of the lamina terminalis secondary to multifocal aqueduct stenosis. c An 8-month-old girl with hydrocephalus secondary to congenital aqueduct stenosis (note the proximal funneling) showing more dilatation of the third ventricle recesses and more bulge of the lamina terminalis and third ventricle floor. d A 5-year-old boy with severe hydrocephalus with effacement of the chiasmatic and suprasellar recesses of the third ventricle. Note dilatation of the pineal recesses