Punctate Cataracts, Significance Unknown
Vickie Halstead RN, CVNS, CCRN, CEN, CLNC
Seeing this statement on the CERF form for your Bichon Frise is alarming: ‘punctate cataracts, significance unknown’. The dog will pass the CERF exam but the CERF form will state ‘breeders option’. What does this mean to Bichon breeders?
Since 1991 the incidence of ‘punctate cataracts, significance unknown’, has ranged from 4% to 6%, but increased to 9% in 2007.
The definition of a cataract is an opacity (lacking transparency) that appears on the lens of the eye. For clear vision the lens must remain transparent in order to refract light to be focused on the retina. Any blemish or a tiny dot is defined as a cataract, which can only be visualized by an ophthalmologist with specialized equipment. Punctate is defined as a dot. In very rare situations a dog can be born with this blemish on the lens, or it can be caused by trauma, infection, inflammation, or exposure to toxins.
Because the outcome of this cataract is difficult to determine, it is called ‘significance unknown’. Therefore, a punctate cataract is a tiny dot on the lens that is unlikely to progress to a true genetic juvenile cataract, however the cataract must be monitored for progression. If in doubt, the prudent approach is to assume that the cataract is inherited. If it progresses (grows in size), it is diagnosed as a genetic cataract.
Three factors help determine the significance of punctate cataracts:
- If this dot is on the front of the lens, it is even more unlikely to progress to a genetic cataract because the Bichon genetic cataracts primarily develop on the back of the lens.
- If this dot does not progress in size over time, genetic cataracts can be ruled out.
- If this dot is only present in one eye, it is unlikely to be a genetic cataract, which most often develop in both eyes.
Breeding Advice:
‘Breeder option’ on the CERF form means caution is advised. If the punctate cataract has not grown in size over a period of at least one year and is present on the front of the lens, Bichon genetic cataracts can be ruled out and breeding is allowed after a discussion with the ophthalmologist.