What it is
At the back of the eye lie the layers that make sight possible: the retina, which catches light, and beneath it the choroid, which feeds the retina with blood. In this condition these layers do not develop properly while the puppy is still in the womb. The changes range from a small, thin patch of choroid to a gap in the tissue around the optic nerve, where the eye connects to the brain.
The condition is inherited and present from birth, and the changes in the eye do not worsen with age the way a degenerative disease does. Even so, the more severe forms carry a risk of the retina detaching or of bleeding inside the eye, which can take away sight.
A dog with a mild form may never show anything you can notice. If sight is lost, a dog leans on its nose and hearing, and furniture left in its place and a predictable home help it find its way.
Signs you may notice
- Bumps into furniture
- Hesitates on stairs
- Misses a thrown toy
- Sudden loss of sight
- Blood visible inside the eye
Dogs with a mild form may show no noticeable signs at all, and the changes are seen only when a vet examines the back of the eye. With a more severe form the dog may see less well and bump into things, and a sudden loss of vision is a sign that it needs a vet immediately.
When to see a vet
Sudden loss of sight or blood inside the eye needs a vet immediately. If your dog seems to be seeing less well over time, book an eye examination.
This is general information, not veterinary advice. For your own dog's health, tests and treatment, see a vet.