Thank you for posting your query.
Based on the information you have provided, the most likely cause for the lesion in the cerebellum
would be a post-inflammatory or post-infective lesion.
An arachnoid cyst
is normally present from birth, so, if it was not seen in your earlier scans, it is unlikely to be an arachnoid cyst.
Similarly for glioma
or a cancer to be cystic is quite rare.
I would think you should wait and watch and repeat an MRI
after 6-8 weeks to see the resolution or progression of the lesion, to decide about any surgery.
Please get back if you require any additional information.
Dr Sudhir Kumar MD (Internal Medicine), DM (Neurology)
Senior Consultant Neurologist
Apollo Hospitals, Hyderabad,
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