By Dr. Becker
Anterior uveitis is a technical term to describe inflammation of the front of the eye.
There are actually three layers to your dog's eye. The outer layer is composed of the clear cornea and the white sclera. The innermost layer is the retina. And the layer in between is the uveal tract or uvea, which is rich in blood vessels. The uvea is composed of the iris at the front, the ciliary body that produces fluid inside the eye, and the choroid, which nourishes the retina in the back of the eye.
If your dog has anterior uveitis, it means there is inflammation of the iris and ciliary body within the uvea of the eye. The disease is also known as iridocyclitis, and it is a quite painful condition that can ultimately threaten a dog's vision.
Because of the uvea's rich blood supply, it's a natural target for problems that originate in other parts of a dog's body. Uveitis is a common secondary condition that results from a disease process elsewhere in the body.
Causes and Symptoms of Anterior Uveitis
Anterior uveitis can have a variety of causes, including autoimmune disease; local tumors or cancers of the eye; trauma or injury; metabolic disease; lens protein entering into the eye fluid (which is usually the result of cataracts); a parasitic, fungal or bacterial infection such as leptospirosis, a heartworm, leishmania, Lyme or Rocky Mountain spotted fever infection; or a viral disease like canine herpes, distemper, or adenovirus.
Sometimes, anterior uveitis is idiopathic, meaning no underlying cause can be determined.
A dog with anterior uveitis will have pain in the eyes. There may also be squinting, pawing at the eyes, eye redness, excessive tearing or discharge from the eye, change in the appearance of the pupil (it may look smaller or take on an odd shape), change in the shape or color of the iris, swelling of the eyeball, or a dull or cloudy-looking eye.
Diagnosis and Treatment Options
Your veterinarian will take a complete medical history and conduct a physical exam, including the use of an ophthalmoscope to look into your dog's eye, and a tonometer to measure the pressure within the eye.
A complete blood count and biochemical profile will also be done to look for the presence of an autoimmune disease, an infectious organism, or another potential cause of the eye problem. Other tests can include x-rays and ultrasound imaging, as well as drawing fluid from the eye for microscopic examination.
Treatment options for anterior uveitis will depend on the diagnosis. The condition should be treated aggressively to prevent further damage to the eye, including ocular infections, corneal scarring or ulcers, corneal vascularization, corneal mineralization, cataracts, glaucoma, lens luxation, retinal detachment, keratoconjunctivitis sicca (KCS) or dry eye, and potentially, blindness.
In every case, regardless of the cause of uveitis, eye drops and ointments are prescribed, along with medications to manage pain and inflammation. If an infection is present, the appropriate medication will be prescribed. Very rarely, surgery to remove the eye is necessary to resolve an underlying tumor that's causing secondary disease like glaucoma.
As difficult as it can be to put drops or ointments into your dog's eye, it's tremendously important to follow your veterinarian's instructions in order to preserve your dog's vision. It's also important to follow up with your vet as necessary.
It's a good idea to get in the habit of looking carefully at your dog's eyes each day to note any changes, and make sure to keep regular follow-up appointments with your veterinarian to have your pet's eyes professionally examined.