here is the info
Hydrocephalus in Dogs
how old is he? I think a neurologist is best to check him out with seizure issues and liver shunt ruled out - if he is over 3 then could be epilepsy but if under three then neurological exam is a great start. Sounds like you have a good new vet that is on top of things
if having seizures make sure NO ROSEMARY in any treats or food that triggers seizures in dogs prone to them
also join a yahoogroups.com group called congenital dogs the owner had a hydrocephalus puppy