Microphthalmia in Cavaliers:
Genetically Caused, Abnormally Small Eyeball

Microphthalmia is an inherited defect which is particularly common in the Cavalier King Charles Spaniel. One or both of the dog's eyes is smaller than normal, resulting in restricted vision and possible blindness.
There is no treatment for microphthalmia.
All CKCSs should be examined at least annually by a board certified veterinary ophthalmologist. They are listed on this webpage of the American College of Veterinary Ophthalmologists website.
Breeders' Responsibilities
The Genetics Committee of the ACVO recommends that CKCSs affected with microphthalmia not be bred. The Canine Inherited Disorders Database also recommends that Cavaliers suffering from microphthalmia not be bred, nor should the dog's parents and any of its siblings. All Cavalier King Charles Spaniel breeding stock should be examined by board certified veterinary ophthalmologists and cleared by the veterinarians for microphthalmia.
Related Links
Eye Disorders
American College of
Veterinary Ophthalmologists (ACVO)
Veterinary Resources
Posterior Lenticonus, Cataracts, and Microphthalmia: Congenital Defects in the Cavalier King Charles Spaniel. Narfstrom K, Dubielzig R, J Small Animal Practice 25:669 1984.
Control of Canine Genetic Diseases. Padgett, G.A., Howell Book House 1998, pp. 198-199, 241.
Ocular Disorders Presumed to be Inherited in Purebred Dogs. Genetics Committee, A.C.V.O. 1999.
Guide to Congenital and Heritable Disorders in Dogs. Dodds WJ, Hall S, Inks K, A.V.A.R., Jan 2004, Section II(199).
Breed Predispositions to Disease in Dogs & Cats. Alex Gough, Alison Thomas. 2004; Blackwell Publ. 44-45.
Ophthalmic Disease in Veterinary Medicine. Martin C.L. Manson Publ. 2005.

