my dog had a stroke when she was 15 years old and lived another three years after that. Strokes are caused when an obstruction (usually a blood clot) interferes with the blood supply to a part of the brain. It's usual for the head to be tilted, the dog to walk in circles and for the eyes to flicker. All these symptoms should decrease as the condition improves but in some cases they don't disappear completely. Strokes in dogs are not quite the same as strokes in humans. As your dog is already seeing a vet for his epilepsy, why not have a chat with him/her about it - the more you know the more you can help your dog. I hope he improves soon. Also, google in strokes in dogs and there are lots of sites to help you.