Cataracts can develop in dogs' eyes and many other animals, often linked to aging but sometimes appearing earlier due to genetics or environmental influences. They manifest as clouded or opaque areas on the eye's lens, potentially causing vision problems or blindness if left untreated. This article highlights posterior polar subcapsular cataracts (PPSC), sometimes called star cataracts, a hereditary type frequently affecting younger dogs in the United States.
Cataracts cause the lens of the eye to become cloudy, which can involve one or both eyes. While they don’t cause pain, cataracts can progressively impair a dog's vision. Posterior polar subcapsular cataracts have a distinctive irregular white or light spot on the back portion of the lens that resembles a star or distant galaxy, differing from the generally uniform clouding seen with other cataracts.
This form of cataract typically grows slowly but may more dramatically affect vision once fully formed. Vision loss associated with PPSC usually develops over an extended period.
PPSC is inherited and often emerges earlier than common cataracts, usually between 6 to 18 months old, but sometimes puppies as young as 6 to 8 weeks can show signs. Both eyes are generally affected simultaneously.
In the U.S., this condition is notably more prevalent in specific breeds due to genetic factors. Popular breeds such as Rottweiler puppies, Labrador Retriever puppies, and Golden Retriever puppies are among those prone to developing PPSC. Ethical dog ownership involves understanding breed-related health issues and obtaining dogs from reputable breeders who conduct thorough health screenings.
PPSC is believed to result from a dominant hereditary gene with incomplete penetrance, meaning a dog needs to receive the gene from only one parent to be at risk. However, not every dog carrying the gene will develop cataracts.
While there are currently no specific diagnostic tests for PPSC, broad DNA testing aimed at evaluating eye health is recommended for breeding dogs. Avoiding breeding affected dogs is critical in decreasing the spread of this condition to future litters.
Dog owners should watch for:
If you observe these indicators, prompt evaluation by a licensed veterinarian or veterinary ophthalmologist is essential.
A veterinary ophthalmologist will perform specialized exams, often involving magnification and bright light, to confirm cataracts and exclude other eye conditions. Additional tests may be necessary to assess general eye health and detect underlying issues such as diabetes mellitus, a common cause of cataracts in dogs.
Surgery, typically phacoemulsification to remove the cataract and restore eyesight, is the most effective treatment. Early diagnosis and intervention improve the chances of a successful outcome. However, surgery may not be recommended for all dogs, particularly older pets with other health concerns.
Postoperative care includes close monitoring for any cataract recurrence and continuous eye health management.
Although medical therapies cannot reverse cataracts, managing systemic health conditions like diabetes can help slow cataract progression. Regular veterinary check-ups are vital for maintaining eye health.
Dogs diagnosed with PPSC should not be bred to prevent hereditary transmission. It's important to acquire puppies from reputable breeders who follow comprehensive health screening protocols, including eye examinations approved by veterinary ophthalmologists.
Early veterinary assessment and treatment when symptoms appear are important steps to preserve quality of life for affected dogs.
Beyond PPSC, other hereditary cataracts affect different breeds, and environmental factors including diabetes, trauma, inflammation, aging, and poor nutrition also contribute to cataract development in dogs across the U.S.
Reliable sources recommend routine eye checks, prompt diagnosis, and a tailored combination of surgical and medical management to maintain optimal eye health and vision in dogs.