This is an example of chronic small vessel disease, which also includes small unruptured aneurysms and a colloid cyst.

The colloid cyst has remained unchanged on serial CTs over a decade. MPR views in this case were degraded but show it in a position above the foramen of Monro.

Although MRI would be a better modality to determine if there have been any new lesions, particularly in the posterior fossa, the patient was already on stroke preventative medication and this was all attributed to pre-existant small vessel disease.