Unilateral Cataracts in Canines

Trauma is a common cause of a unilateral cataract.
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A unilateral cataract affects one eye only, causing a clouding of the lens, located behind the colored iris. A mature cataract will cause vision impairment like that of looking through a pane of white-painted glass. Cataracts will progress when left untreated, eventually causing blindness in the effected eye.

Causes and Symptoms

Unilateral cataracts are related to isolated incidents and can be associated with ocular abnormalities such as persistent hyperplastic primary vitreous, posterior lenticonus, posterior pole tumors and anterior segment dysgenesis. Interauterine infection, specifically rubella, can occur in the affected eye. A cloudy, discolored, bluish-white color in the eye; rubbing and squinting of one eye; bumping into walls; and general clumsiness are signs your dog has a cataract.

Risk Factors

Unilateral cataracts that develop due to trauma are more common in younger dogs due to their playful nature within the litter and exposure to multiple playmates at one time. Congenital unilateral cataracts are present at birth, juvenile unilateral cataracts develop up to 2 years after birth and adult unilateral cataracts develop between 2 to 10 years of age. German shepherd, French bulldog, Irish setter, Akita, beagle and Yorkshire terrier breeds are prone to genetic cataracts.

Diagnosis and Treatment

Veterinarians will look closely at the outer parts of the eye and the retina, plus conduct a complete ophthalmic exam, urinalysis and biochemical profile to determine the type and severity of the cataract. At times, veterinarians will recommend a licensed ophthalmic veterinarian for further treatment. Cataracts that are not approved candidates for surgical removal are secondary to radiation therapy and anterior uveitis, plus cataracts that are accompanied by retinal degeneration or detachment. Topical treatment such as topical and systematic anti-glaucoma and topical corticosteroids are used.

Surgical Removal

Surgery is a common treatment recommended by veterinarians. However, your dog's health and the status of certain criteria are what make your dog a suitable candidate for unilateral cataract surgery. Surgeries are conducted by a licensed ophthalmic veterinarian. Three potential surgical techniques are considered for removal of the cataract. Techniques include phacoemulsification, extracapsular and intracapsular. The veterinarian will discuss the most suitable surgical procedure. The success rate for cataract surgery is high, about 90 percent to 95 percent. However, short-term complications such as glaucoma and post-operative inflammation can occur.