Try this site for some basic information:
http://www.epilepsy.com/epilepsy/epi...oxgastaut.html
The jist of it is: multiple seizures of different types, specific EEG abnormality, and some degree of developmental delays. They may or may not have some type of brain abnormality.
Ketogenic diet-
http://www.stanford.edu/group/ketodiet/FAQ.html
Parents should have diet/menu already set up by a dietitian. Big thing with that is child cannot have any other foods, or different amounts-things tend to be measured down to the gram and are very specific in the amounts of protien and fat. You may have to occasionally test urine for ketones.
Hope this is a little help!