Pet ophthalmologists can treat cataracts

ByMartha R. Camara

Aug 31, 2020

Q The vet said my 10 year old dog, Addie, had small cataracts in both eyes. Due to the pandemic, I haven’t been able to speak with the vet in person, so I don’t know how much of an issue that is. Please educate me on cataracts.

A A cataract is an opaque area of ​​the lens that blocks the transmission of light to the retina and impairs vision. Addie’s cataracts are small, so she’s probably doing fine.

Your vet will monitor Addie’s cataracts at each exam, noting if they are growing and “mature”. A mature cataract encompasses the entire lens and blinds the eye. It can also cause two painful conditions: uveitis, or inflammation of the eye, and glaucoma, increased pressure inside the eye.

Addie’s cataracts may or may not progress to this point. If so, your vet might suggest seeing a licensed veterinary ophthalmologist, who can remove them and insert an artificial lens into each eye to restore vision, as is done for humans.

Cataracts have many causes. Most of those that occur in purebred dogs are hereditary. In dogs with poorly controlled diabetes, cataracts can form very quickly. Those that develop in older dogs as a result of sun exposure usually grow slowly and do not become a problem.

Toxins and trauma can also cause cataracts, as can an electric shock from gnawing on a power cord. Nutritional imbalances can also precipitate cataracts.

Each time your vet examines Addie, ask if her cataracts have changed and if it’s time for a veterinary ophthalmologist to examine her.

Q Hobie, my middle aged indoor/outdoor cat, woke up this morning with a very abnormal eye. Her upper eyelid droops and a white film covers the inner corner of her eye. What caused this? Will this resolve itself or should I take Hobie to his vet?

A I would recommend a visit to the vet. It seems that Hobie has Horner’s syndrome, which is not a specific disease but the name of a group of clinical signs.

Horner’s syndrome, which usually occurs in one eye, is characterized by an abrupt onset of drooping of the upper eyelid; raised nictitans, or third eyelid, the white film you see in the inner corner of Hobie’s eye; retraction of the eyeball deeper into its socket; and the constriction of the pupil so that it remains small.

These changes result from damage to the nerves of the sympathetic nervous system in the head or neck. The sympathetic nervous system is responsible for the fight or flight response.

These nerves open the eyelids wider, retract the nictitans, hold the eyeball forward in the socket, and dilate the pupil, thereby improving vision and giving the cat a fierce stare.

When the body is at rest, the sympathetic nervous system is balanced by the parasympathetic nervous system. His nerves have the opposite effects.

So when the sympathetic nerves are damaged, only the parasympathetic nerves exert an effect – and Hobie exhibits Horner’s syndrome.

The causes are many and include trauma, middle ear infection, tumor growing on a nerve, or eye problem. Often a cause cannot be found.

Horner’s syndrome itself does not require treatment, but whatever the cause, it should be evaluated. For example, Hobie may have a bite on his neck which is not obvious because the cat’s skin is elastic and closes over wounds. However, bacteria deposited under the skin can cause a painful abscess.

So take Hobie to his vet, who can determine what treatment, if any, is needed.

Lee Pickett, VMD, practices companion animal medicine in North Carolina. Contact her at

[email protected]