Morgan,
You did not say what the Vet called your kitten’s condition but it sounds like “Water on the Brain”. Treatment for this conditon (if this is kitty’s problem and it is rare in cats) will prove very expensive and may still have a bad outcome. Most Vet’s will not even offer putting you in touch with a facility equipped to perform the delicate shunt surgery that would allow the fluid to drain. Even medication such as steroids would be an ongoing expense.
You need to ask your Vet more questions and research the options. I know you love your baby and euthanization is the most dreaded option we have but at least we have it for our pets.
If you find you have to take this path, we will be here to support and grieve with you.
MORE INFO HERE:
http://www.marvistavet.com/html/hydrocephalus.html
HOW DO ANIMALS GET HYDROCEPHALUS?
Most animals with hydrocephalus are puppies with congenital anomalies leading to hydrocephalus (they are not born with hydrocephalus but they are born with the anatomical problems that quickly lead to hydrocephalus). The most commonly affected breeds are those with a natural tendency towards the domed-head: Chihuahua, Pomeranian, Yorkshire terrier, English bulldog, Lhasa apso, Pug, Pekingese, Boston terrier, Maltese, toy poodle, and Cairn terrier)
What happens to these puppies is that parts of the brain called the “rostral colliculi†fuse together causing a narrowing of the aqueducts that carry the cerebrospinal fluid. In the cat, more common causes of narrowing of the aqueducts include maternal exposure to the drug griseofulvin (used to treat the ringworm fungus), and maternal exposure to the feline distemper virus during pregnancy. Inflammatory conditions in the brain can also cause swelling that narrows the aqueducts.
WHEN TO SUSPECT HYDROCEPHALUS
When a puppy or kitten is 8-12 weeks old, symptoms are usually evident. The skull looks especially round and there is an open fontanelle (“skull soft spotâ€) on the top of the head. The pet may show what is called the “setting sun†sign which means the eyes are directed downwards (and possibly outwards). The animal may suffer from seizures (less than 20% of affected puppies), blindness, pressing the head into corners, or extreme difficulty in house-training (over 75%).