Nuclear Sclerosis

Nuclear/Lenticular Sclerosis

By Dr. Karen Burgess

Why do dogs develop nuclear sclerosis?
Nuclear or lenticular sclerosis is a normal aging process of the eyes.

What does a nuclear sclerosis look like?
Most owners will notice a symmetrical gray blue haze to the eyes often easier to see from the side than the front. Sometimes nuclear sclerosis can be confused with cataracts which are more opaque and white in nature. Cataracts represent a more serious condition that affects vision.

Does nuclear sclerosis affect vision?
Typically nuclear sclerosis does not significantly impact vision. Some owners may notice change in depth perception or seeing items close up. Additionally as the normal retina ages, night vision may become more difficult.

What are treatment options for nuclear sclerosis?
There is no treatment for nuclear sclerosis indicated or necessary.

Dry Eye (KCS)

KCS (Kertaoconjunctivitis Sicca)

By Dr. Karen Burgess

Why do dogs develop KCS?
The most common cause of KCS in dogs is an autoimmune related disease. With immune system disease, the body starts inappropriately attacking something that is normal, in this case the tear producing cells. There may be a genetic predisposition to the development of KCS and many breeds are thus predisposed. Other potential causes of dry eye include a reaction to particular medications or hypothyroidism. Sometimes tear production will appear decreased due to inflammation in other parts of the eye; once the underlying disease is addressed the tear production may return to normal in these cases. Lastly there is a neurologic cause that typically causes a very dry nose on the associated side of the face with the diseased eye.

What does a KCS look like?
Owners may first notice increased ocular discharge with KCS. The eyes may be painful demonstrated as squinting, holding the eyes shut, or excessive blinking. Over time, dogs with KCS are more prone to developing corneal ulcers and scarring which often appears as black pigment on the cornea.

How is KCS diagnosed?
A Schirmer Tear Test (STT) is used to diagnose dry eye. This test involves placing a small strip of test paper under the eyelid and quantifying the amount of tears produced over a minute time. Previous application of any eye medication or drop can affect results of the STT. Additional testing may be done to evaluate the cornea for damage (fluorescein staining), to evaluated intraocular pressure (looking for associated glaucoma), and to evaluate the quality of tears being produced.

What are treatment options for KCS?
The first goal of treatment for dry eye is to replace tears artificially allowing protection of the delicate cornea. This is done by administering a topical tear replacer that is often applied every few hours throughout the day (the more the better). The second goal of treatment is to stimulate the body’s natural production of tears. Tacrolimus and cyclosporine are the most commonly used medications for this and are applied topically at least twice daily. These medications are often compounded or specifically made by the pharmacist for a specific pet. General hygiene is also important, gently wiping the face and eye area to help prevent buildup of debris. Ultimately there is surgery available to treat dry eye if topicals are not an option, but this is not without the possibility of complications.

What is the prognosis with KCS?
With the medications currently available dogs with KCS have a good prognosis for returning to a normal comfortable eye. It is important to understand that treatment is life-long and cure is not expected.

Corneal Ulcer

Corneal Ulcer/Erosion

By Dr. Karen Burgess

What causes corneal ulcers?
Corneal ulcers are typically caused by external trauma, foreign bodies, chemical irritants such as shampoo, or self-inflicted trauma (example pet scratching or rubbing eye). Some breeds are also predisposed to decreased tear production which can dry out the cornea leading to erosions.

What are symptoms of corneal erosions/ulcers?
Corneal lesions are usually very painful. In an effort to relieve associated itchiness and discomfort, pets will often rub the affected eye against the ground, against furniture, or with their paws. The eye will often be held closed, be more sensitive to light, and appear red. Drainage may also be present.

How do you test for a corneal ulcer?
Your veterinarian will apply a fluorescein stain (eye drop) that will effectively highlight any damage to the cornea. Testing for adequate tear production may also be performed.

What is the treatment for corneal ulcers?
The severity of the corneal lesion will determine treatment. In severe cases referral to an ophthalmologist may be necessary for surgery in an attempt to save vision. In milder cases topical eye medications, lubricants, and pain medicine may be prescribed. Atropine drops may also be used to dilate the eye thus helping with discomfort. If atropine is prescribed the dilation will last for several days beyond treatment and will cause light sensitivity. An Elizabethean collar will also be necessary to help prevent any further self-trauma to the eye. In uncomplicated cases the cornea will tend to heal in just a few days. A recheck of the eye should be performed two to three days after initiation of treatment to ensure improvement. Be aware that pets may taste any medications applied to the eye due to tear ducts which drain into the mouth. This may cause drooling or pawing at the mouth after eye medication application. Topical anesthetics are not recommended to treat ulcers as they can hinder healing. If your pet is more uncomfortable after application of eye meds, contact your veterinarian; in some situations a pet may be sensitive to a particular product.

Cherry Eye, Canine

Conjunctivitis (Cherry Eye)

By Dr. Karen Burgess

Why do dogs develop cherry eye?
The third eyelid gland is normally firmly attached to the lower portion of the eye. For unknown reasons, in particular in some breeds, there is weakening of this attachment causing it to pop out. Over time, the now malpositioned gland becomes inflamed and swollen, making it more difficult for it to stay in its proper position.

What does a cherry eye look like?
What most owners notice with a cherry eye is a red swollen mass like appearance protruding from on the nose side of the eye. Cherry eye is typically not painful. They can vary in size and in some cases will come and go.

What are treatment options for cherry eye?
Definitive treatment involves surgically tacking the prolapsed third eyelid gland back in place. This surgery involves a high degree of technical skill for best chances of success and should be performed by and ophthalmologist (veterinarian that has received advanced training in ocular disease and surgery). There is another surgical procedure that involves removing or amputating the third eyelid gland. This is not recommended and can lead to lifelong complications with tear production and thus a potentially painful and non-visual eye. In some cases, use of a topical steroid and gentle external massage can pop the proptosed gland back in place. In some milder cases this can be done at home by owners as needed for temporary control.

What is cherry eye’s prognosis?
With surgical treatment performed by an ophthalmologist the prognosis is good. In some cases (up to 20%) additional surgery may be required, thus making it that much more important to have a skilled person doing the surgery from the beginning. Untreated cherry eye can eventually damage the cornea, affect vision, and become painful for the pet.