Presentation
Work up for headache.
Patient Data
Age: 60 years
Gender: Female
From the case:
Mega cisterna magna
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Focal enlargement of the CSF-filled subarachnoid space is seen in the posteroinferior portion of the posterior cranial fossa, consistent with mega cisterna magna, an anatomical variant.
Case Discussion
Mega cisterna magna is usually an incidental neuroimaging finding, and no imaging follow up is needed. Arachnoid cyst and epidermoid cyst of the posterior fossa can be challenging to distinguish from a mega cisterna manga on CT images.