Presentation
Increasingly odd behavior. Previous CT suggested an intracranial cystic lesion
Patient Data
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Large ovoid cystic mass, 70 mm in diameter located within the lateral ventricle, located near the trigone, results in contralateral midline shift of 15 mm and prominent left temporal horn dilatation. There is moderate periventricular edema (transependemal CSF spread) due to obstruction to CSF outflow.
Multiple foci of small microangiopathy and a microbleed within the right parietal lobe.
Case Discussion
This patient was referred for MRI investigation of a suspected intracranial cystic mass, after initially presenting with bizarre behavior. MRI demonstrates a large simple intraventricular cyst compressing the left hippocampus, which may be the cause of the patient's symptomatology.
The origin of these cysts is uncertain and can arise from a number of structures. Some are arachnoid cysts whereas others ependymal cysts, neuroepithelial cysts or very large choroid plexus cysts. Distinguishing between them on imaging is impossible.