Cataracts can affect the eyes of dogs and many other animals, often associated with old age but sometimes developing earlier due to hereditary or environmental factors. They appear as cloudiness or opacity on the lens of the eye and can lead to vision impairment or blindness if untreated. This article focuses on posterior polar subcapsular cataracts (PPSC), also known as star cataracts, a specific hereditary type often affecting young dogs.
Cataracts cause clouding of the eye's lens, affecting one or both eyes. While painless, they compromise vision significantly over time. Posterior polar subcapsular cataracts have a unique irregular white or light opacity on the back surface of the lens, resembling a distant galaxy or star, unlike the even opacity seen in other cataracts.
This type tends to be slow-growing but can more acutely impact vision once fully developed. Despite this, vision deterioration may take considerable time.
Posterior polar subcapsular cataracts are hereditary and tend to appear earlier than typical cataracts, often between 6 to 18 months of age. In some cases, puppies as young as 6 to 8 weeks old can develop them. Generally, these cataracts affect both eyes simultaneously.
This condition is more common in certain breeds due to genetic predisposition. Notably, Rottweilers, Labrador retrievers, and golden retrievers are more prone to developing PPSC. Responsible dog ownership includes being aware of breed-specific conditions and choosing reputable breeders who perform health screenings.
PPSC is believed to be caused by a dominant hereditary gene with incomplete penetrance. This means a dog needs to inherit the gene from just one parent to be at high risk, although not every dog with the gene will express the cataracts.
Currently, there are no specific health tests for PPSC, but generalised DNA testing for eye health is advisable for breeding dogs. Avoid breeding affected dogs to reduce the risk of passing the condition to puppies.
Owners may notice:
If these signs are observed, prompt veterinary examination is recommended.
A veterinary ophthalmologist will assess the eyes using specialised examination techniques to detect cataracts and rule out other eye disorders. They may perform additional tests to evaluate the dog's overall eye health and underlying conditions such as diabetes.
Surgical removal of cataracts, typically through phacoemulsification, can successfully restore vision. Early intervention improves outcomes, but surgery may not be suitable for all dogs, especially older ones with health risks.
Post-surgery, dogs require careful monitoring for potential cataract recurrence and ongoing eye care.
Medical treatments cannot reverse cataracts but managing underlying health conditions can help slow progression. Regular veterinary check-ups are essential.
Dogs diagnosed with PPSC should not be bred to prevent passing hereditary cataracts to future generations. Always seek puppies from reputable breeders who conduct comprehensive health screening.
Ensuring early veterinary examination and treatment when symptoms arise is key to maintaining a good quality of life for affected dogs.
While PPSC is a distinct form of cataract common in certain breeds, other hereditary cataracts affect different breeds, and environmental factors like diabetes, injury, or age also contribute to cataract development widely.
Comprehensive resources recommend early diagnosis, appropriate veterinary care, and a combination of surgical and medical management to sustain vision health.