Presentation
Headache and blurring of vision
Patient Data
Age: 8 years
Gender: Male
From the case:
Arachnoid cyst
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Small right middle cranial fossa extra-axial cystic lesion that is filled with CSF with no visible wall. No enhancement of the lesion or its wall and no diffusion restriction on DWI. No extension through the Sylvian fissure.
Diagnosis - type I arachnoid cyst.
Case Discussion
Usually, arachnoid cysts are accidentally discovered on routine MRI or CT. A simple arachnoid cyst displays no enhancement or mass effect. DWI can help differentiation between arachnoid and epidermoid cysts.