A corneal ulcer is a defect in the cornea, which is the clear, outer surface of the eye. The cornea is made of several layers of cells, and any erosion or damage to these cells creates an ulcer. Corneal ulcers are painful and require immediate veterinary attention.
Risk factors and detection
Corneal ulcers usually result from eye trauma. Other causes include
chemical burns, corneal infection, dry eye (a condition in which the tear
glands don’t produce enough tears), abnormal eyelashes rubbing on the
cornea, foreign bodies lodged behind the third eyelid, and certain diseases. Shampoos are a common cause of chemical burns.
Dogs with corneal ulcers may squint or keep the injured eye closed. The eye will appear watery, and your dog may rub or paw at it. You may also notice signs of conjunctivitis, such as redness of the normally white or pink inner eyelids and tissue surrounding the edge of the eye. Because a deep ulcer can cause the eye to rupture, take your dog to the veterinarian immediately if you notice any of these signs.
A large ulcer may appear as a flat or dull area on the corneal surface. Your veterinarian will use a special eye stain to detect smaller ulcers. The stain will adhere to damaged areas of the cornea, coloring them bright green. If the ulcer is near the inner corner of the eye, your veterinarian will check behind the third eyelid for a foreign body.
Treatment
For shallow ulcers, your veterinarian will prescribe a topical antibiotic
you can apply several times a day. You also may use topical atropine to dilate the eye and help control the pain. One caution: Never put eye drops containing steroids in an eye with an ulcer, because the steroid can make the ulcer worse. If your dog suffers from a condition known as dry eye, it’s important to treat that problem as well.
More severe or nonhealing ulcers may need surgery. Your veterinarian can create a “living bandage” by pulling the third eyelid or a piece of the conjunctiva over the cornea and suturing it in place. This creates a
protected healing environment. If your dog has abnormal eyelashes, the doctor will surgically correct them to prevent future ulcers.
Until the corneal ulcer heals, your dog will need frequent rechecks.
