Dear Mr Gouda,
Mega cisterna magnoa basically means that there is a larger than normal fluid cavity in the back of the brain. This does not specifically require any treatment. Cerebral atrophy
means that there is a shrinkage of the brain volume for some reason.
As far as the symptoms you report, these will need to be assessed by a neurologist
who deals with epilepsies (Epileptologist) and probably undergo other tests depending on what the clinical findings are. With this you should get a better control of the epilepsy
Hope this helps.