Features are more suggestive of an intra-axial cyst, mostly porencephalic cyst. Features that suggest intra-axial location are:

• normal appearance of Sylvian fissure and nearby extra-axial space with no extrinsic mass effect upon the brain surface
• surrounding white matter and lateral ventricle wall around the inner surface of the lesion
• the outer wall, delineated by superficial cortical veins, looks continuous with brain surface
• it is not lined by a grey matter and is associated with a small amount of adjacent FLAIR hyperintensity