Son with seizures

My son is twenty three and autistic. He had an MRI a while back, probably two years ago, with a finding that a part of the brain, (The gangli something or other?) that is supposed to be wrinkly is smoother than its supposed to be, other wise it was normal. Did anyone else get a report like that? His EEG I think was OK, but his seizures are tonic-clonic and according to the school nurse who has seen them, they are very hard seizures, that last about 5 minutes. He usually bites his tongue or cheek and turns pale. He has only had five seizures, the last one was last Sunday. The first one he was taking wellbutrin and changing over to remaron. The second one was after we raised the dose of remaron. The next two were after he had been off the depakote for a while ( he had taken depakote for years for behaviors, then he started having high ammonia in his blood tests, which made him kind of "drunk").The Neurologist then said he had a seizure disorder and put him on topamax. He hadn't had a seizure in 15 months so I asked about taking him off the topamax and the doctor agreed, because I was concerned about the side effects of a kidney stone ( topamax can cause kidney stones). He had a seizure after 4 days of weaning him off the med.