Imaging findings associated with AS
| Direct Findings | Findings Secondary to Obstructive Hydrocephalus | Findings of Associated Malformations |
|---|---|---|
| Aqueduct funneling | Enlarged third ventricular recesses | Abnormal sulcation |
| Blood in the aqueduct | Enlarged ventricular temporal horns | Brain stem abnormality |
| Tectal thickening | Perforated septum pellucidum | Cerebellar hypoplasia |
| Lateral ventricular diverticulum | Cerebellar dysplasia | |
| Callosal thinning and/or dysgenesis | Rhombencephalosynapsis | |
| Macrocephaly | Fourth ventricular dilation | |
| Vermian hypoplasia |
Note:—AS indicates aqueductal stenosis.