Eye problems are a common cause for visits to the vet.
People used to think that a dog's sight is dichromatic (see in black and white). But the latest research suggests that dogs may actually see some colour, though certainly not as much as people do. Depending on the dog breed, their field of vision can vary up to 270 degrees for sight hounds like greyhounds and whippets, and as low as 180 degrees for flat-faced breeds like the bulldog or Boston terrier. People also have a narrow field of vision of 180 degrees.
Dogs can see much better at night than people do. Their eyes are more sensitive to light and motion than ours. They have a structure, the tapetum lucidum that allows them to see in dim light.
Common signs of an eye problem:
- Partially or fully closed eye
- Rubbing at the eye
- Visible third eyelid
- Unequal pupils
Common eye conditions in dogs:
- Dry eye
- Retinal problems (atrophy and detachment)
- Lens luxation
The conjunctiva is the pink tissue surrounding the eyeballs and on the inner side of the eyelids. Eye discharge, redness and pawing at the eyes can indicate a problem such as conjunctivitis. In dogs, it is commonly caused by allergies.
Management of conjunctivitis is largely based on control rather than cure:
- Wipe eyes regularly with sterile saline
- Regular grooming to avoid hair irritating the eyes
- Management of allergies
A lack of tears can result in dry and inflamed eyes (particularly the conjunctiva and cornea).
Common signs of dry eye:
- Mucous eye discharge
- Changes in the cornea
- Vision impairment
Common causes of dry eye:
- Other eye diseases
Breeds commonly affected by dry eye:
- West highland white terrier
- Cavalier king charles spaniel
- Shih tzu
- Miniature schnauzer
- Bull terrier
- Cocker spaniel
Treatment is necessary with veterinary medications such as Cyclosporine and artificial tears.
An eye ulcer refers to a defect in the eye's cornea. There are different types of ulcers with many different causes.
Common causes of eye ulcers:
- Eyelid problem
- Extra eyelashes
- Dry eye
Depending on the cause, it is important that pets receive immediate care to prevent permanent scarring and loss of the eye.
Cataracts are an opacity of the lens.
Common causes of cataracts:
- Endocrine disease such as diabetes
- Other eye diseases
Breeds commonly affected by inherited cataracts:
- American Cocker Spaniel
- Bichon Frise
- German Shepherd
- Golden and Labrador Retrievers
- Siberian Husky
If the cataract is causing problems, surgery is often the only effective method to remove them. A referral to a veterinary eye specialist to determine the appropriate treatment regime, may be recommended.
This eye disorder is characterised by an increase in eye pressure and can result in blindness. Glaucoma is thought to affect approximately 2% of dogs.
Common signs of glaucoma:
- Enlarged eye
- Slightly dilated pupil
- Inflammation of conjunctiva
Breeds predisposed to glaucoma:
- Bouviers des Flandres
- Dandie Dinmont Terriers
- Welsh Terriers
- Basset Hounds
Any eye condition that suddenly appears and is associated with redness, requires immediate veterinary attention.
How to administer eye medication
- Start by cleaning any eye discharge with a cotton ball and sterile saline
- Follow the instructions on the medication and the veterinary label with regard to dosage and frequency
- Place the drops or ointment into the open bottom eyelid. But avoid contact with the eyeball
- Gently close the eye and massage the eyelids over the eyes surface to disperse the medication
Tips to help prevent eye problems:
- Regular cleaning of the eyes with sterile saline
- Regular grooming of the facial hair to avoid irritation to the eyes
- Regular cleaning of the bedding and avoiding dusty environments