Presentation
Left sided weakness.
Patient Data
There is a well defined, CSF density, unilocular cystic lesion within the right frontal lobe. There is no surrounding edema or calcifications associated with the cyst.
There is a cystic lesion in the right frontal lobe measures approximately 4.3 x 2.9 cm which shows CSF signal intensity on T1, T2 and diffusion imaging. No associated edema. No evidence of restricted diffusion. Cyst does not communicate with the ventricles or the subarachnoid space. The wall of the cyst measures no more than 2 mm.
Case Discussion
The MRI and CT demonstrate the classic findings of a neuroglial cyst. The lesion is basically a cyst within the white matter that appears simple, with CSF density on all imaging modalities and is without any associated edema.
Differentials would include porencephalic cyst (note absence of any volume loss or gliosis) or less likely cystic glioma / metastasis (absence of any edema or enhancing / solid component basically excludes these) or cyst from prior infection.
Presence of weakness is a little concerning however and follow-up would be required.