Findings
There are no areas of restricted diffusion to suggest an acute infarction.
There is diffuse enlargement of the lateral and third ventricles with small fourth ventricle and there is transependymal CSF flow identified as well. There is sulcal enlargement but the ventricular enlargement seems to be greater than expected for sulcal enlargement.
A few tiny foci of hemosiderin deposition are present in the subcortical white matter, age-appropriate.
Both vertebral arteries the basilar artery and both carotid arteries are patent. There is mild sinus inflammatory change in the ethmoid and maxillary sinuses. Sylvian fissure enlargement is present bilaterally.
Impressions
Given the pattern of disproportionately dilated sylvian fissures and disproportionately enlarged subarachnoid spaces, one should consider adult normal pressure hydrocephalus.
Alternatively, since the hydrocephalus is predominantly affecting lateral and third ventricles it raises the possibility of a functional obstruction at the cerebral aqueduct with evidence of transependymal CSF flow.