The inquisitive and vocal Siamese has plenty of positive traits that make it a unique and lovable breed. Unfortunately, good eyesight isn't one of them. Siamese kitties are often born slightly cross-eyed, but they are also predisposed to severe vision problems that can make them eventually go blind.
Siamese have a notably higher risk of inheriting traits that lead to vision loss than most other cats. Breeds closely related to the Siamese, including Javanese, Ocicat and Balinese, suffer from some of the same genetic weaknesses. That doesn't mean your cat's eyes are a lost cause, though. Even if your Siamese shows signs of retinal degeneration, abrasion or a birth defect, it doesn't mean he will be completely blind. Talk to your vet and ask him about treatment options for your kitty.
Progressive Retinal Atrophy
Research has shown that the mutation of a single gene in the Siamese genome is related to progressive retinal atrophy (PRA). A survey of cats in the Siamese group showed about one-third of them had the mutated gene, according to University of California–Davis Veterinary Genetics Laboratory. Cats with PRA slowly lose their vision as their retinal lens deteriorates. While there is no cure or treatment for it, the atrophy does not show many visible signs and isn't a painful experience. Affected cats eventually become completely blind, although this may not occur until your pet is well into old age.
You've probably heard of feline glaucoma before. It's actually a pretty common health problem in cats of all breeds, but most cats that have it aren't genetically predisposed. Siamese are one of the few breeds that can be born with primary glaucoma, which is strictly hereditary, according to Cornell University College of Veterinary Medicine. Cats of other breeds may develop secondary glaucoma, which is associated with aging. Glaucomas are small sacs of fluid stuck between the lenses of your cat's eye. The liquid pressures your cat's ocular nerves and steadily dims his vision over time. There is no cure for glaucoma, but your vet can prescribe anti-inflammatory compounds or eyedrops to ease your cat's discomfort.
If your Siamese's eyes dart back and forth constantly, it's probably not because he's been watching cars go by though the window all day. Convergent squint is caused by a mixup in the nerve wiring behind your kitty's eyes. Some nerves from each eye connect to the vision center of the other, which prompts cats to squint and look back and forth frequently, according to the Feline Advisory Bureau. Himalayan and relatives of the Siamese breed are also prone to this problem. There is no way to treat convergent squint, but you'll be glad to know that your cat won't become completely blind from it.
Quentin Coleman has written for various publications, including All Pet News and Safe to Work Australia. He spent more tan 10 years nursing kittens, treating sick animals and domesticating semi-feral cats for a local animal shelter. He graduated from the University of Delaware with a bachelor's degree in journalism.