Neuroglial cysts (also known as glioependymal cysts) are rare, benign epithelial-lined cystic lesions that can potentially occur anywhere in the neuraxis. On imaging they are characterised as CSF-like parenchymal cysts with smooth, rounded borders and minimal-to-no surrounding signal intensity abnormality.
They are rare and represent <1% of intracranial cysts.
Neuroglial cysts are congenital lesions that develop a sequestration of neural tube embryonic elements that develop into a glial cell lined, fluid filled cavity, located within the white matter 4. Location
They can be intra- or extra-parenchymal with the former being more common. The frontal lobe is thought to be the most typical location 1,3.
Typically seen as a well defined, non enhancing, hypodense (CSF density) unilocular cystic lesion with no surrounding oedema. They do not calcify. MRI
Neuroglial cysts usually follow CSF signal. Hence they are hypointense on T1 and hyperintense on T2. They do not enhance with gadolinium. They are usually suppressed on T2 FLAIR sequences. Differential diagnosis
General imaging differential considerations include:
Porencephalic cyst: communicates with the lateral ventricle, usually shows surrounding gliosis
Arachnoid cyst: typically extra-axial, enlarged perivascular space, typically multiple cluster around the basal ganglia
Neurocysticercosis: usually <1 cm, partially enhance
cerebral hydatid cyst: usually spherical, may be indistinguishable
Ependymal cyst: periventricular, may be indistinguishable
Epidermoid cyst: usually do not follow CSF signal in all sequences restricted diffusion