Seizures

[Melody]

I have a TBI as a result of a serious car accident in 2005 after being hit at high speed by a drunk driver. I started experiencing seizures a few times a month, which have now increased to up to 4 - 6 times a day, lasting 10 minutes to one hour. The seizures include staring, unresponsiveness, inability to move physically. I am aware during the episode. I can hear and feel but not respond. I had one recently while in the neurologists office for 12 minutes, which he observed. During my recent EEG test I had a seizure that lasted for one hour throughout the test. The EEG results, however, do not show any abnormal brain activity. The neurologist said the EEG was normal. I am being treated with Keppra, which has reduced the seizures and their duration to 2/day lasting ~ 15 minutes each. I'm only taking the initial dose of 250 mg/day of Keppra, and won't be on full strength until a few weeks.

Has anyone else experienced seizures that cannot be measured? There is a reluctance to give a diagnosis, because of the EEG. Are any other explanations for these symptoms?