Presentation
Incidental finding on CT. MRI requested to further evaluate.
Patient Data
A very well circumscribed CSF intensity cystic spaces at the inferior margin of the lentiform nucleus on right is demonstrated. It follows CSF on all sequences including diffusion-weighted imaging, demonstrates no peripheral edema or gliosis, and has a perforator traversing it, best seen on post-contrast studies. No solid enhancing component. It is an isolated abnormality. The remainder of the brain is unremarkable with no intra- or extra-axial abnormality.
Conclusion:
Appearances are characteristic of a large perivascular space and requires no further imaging or followup.