Reason: focal abnormalities History: new onset seizure, focal onset on EEG There is no evidence of intracranial hemorrhage or acute infarct. The brain parenchyma and pituitary gland appear unremarkable. The ventricles are normal in size and configuration. There is a cystic lesion which follows CSF signal which appears to originate in the quadrigeminal plate cistern measuring 2.2 x 2.0 cm. This lesion causes leftward displacement of the pineal gland and internal cerebral veins. A small cavum vergae is noted. The hippocampi are symmetric without evidence of atrophy or abnormal signal. No heterotopic gray matter. Midline structures are intact. The major cerebral flow voids are intact. The orbits, skull and scalp soft tissues are grossly unremarkable. The paranasal sinuses are unremarkable.
1.Cystic lesion in the region of the quadrigeminal plate cistern likely represents an arachnoid cyst. The relevance of this finding to the patient's presenting clinical symptoms is uncertain.2.Normal appearing hippocampi without abnormal signal or atrophy. No other specific lesions are seen which would account for seizures.