Eyelid Coloboma in Cats
Coloboma is by definition “a piece of missing tissue from birth”. Most commonly the lateral upper eyelid is affected/missing in cats. Often intraocular birth defects are identified in these kittens/cats and may include: anterior segment dysgenesis/persistent pupillary membrane (PPM), iris defects, lens defects and chorioretinal defects. Eyelid Coloboma is seen in stray kittens, and the status of the mother (queen) is often not known. There are a few reports of eyelid Coloboma in purebred cats. The development of this birth defect is poorly understood in cats and has so far not been proven to be and inherited disorder.
Some cats have marked changes of the cornea due to trichiasis (hairs rubbing on the eye), while others have minimal discomfort/changes. Surgical options generally consist of reconstructive surgery of the upper eyelid, to provide the cat with a functional upper lid of normal length. Pros and cons of surg