Cerebral cavernous malformations: spectrum of neuroradiological findings.

Cavernous malformations (cavernomas) are hamartomatous lesions formed by sinusoidal vascular spaces, with no cerebral parenchyma between them. Seizures are the most usual clinical presentation. They are dynamic lesions, producing changes throughout their evolution. The majority are located in the supratentorial region, but up to 20% of cases they are found in the posterior fossa. In computed tomography (CT) and in magnetic resonance (MR) their typical presentation is as a well defined round or oval lesion, with or without a minimal mass effect or oedema, with little or no contrast enhancement. Their appearance in MRI will depend on the stage of the haemorrhage, a T2 echo gradient being the most sensitive sequence. Angiography do not usually detect cavernomas. However, it may demonstrate a venous developmental anomaly. Cavernomas may present with atypical characteristics, as regards their size, appearance, location and number.