Cataracts in Dogs

The most common cause of cataracts is genetics. Poodles, Cocker Spaniels and Huskies are some of the breeds that are more likely to develop cataracts. In other cases, cataracts are congenital, meaning that dogs are born with them. Veterinarians suggest that the way to avoid this possibility is not to breed dogs that develop cataracts at a young age. 

Some owners will notice that as their dogs age, their eyes become cloudy. While this may be evidence of cataracts it is not necessarily the case. The lens is made of tissue fibre that become more compact and fibrous with time and look cloudy. This is called nuclear sclerosis and is not the same as cataracts.

Cataracts occur when the functioning of the capsule holding the lens is disrupted. An inflammatory reaction is triggered as the body picks up on the abnormality causing cataracts and other conditions like uveitis. 

Diabetes mellitus can often lead to cataracts. The excessive sugar cannot be absorbed fully by the solution in the eyes. Instead, the sugar is turned into a substance called sorbitol which has the tendency to draw water towards it. The excessive water leads to cloudiness and causes cataracts to form.

As suggested above, what appears to be a cataract may not necessarily be so. It is a good idea to go to your vet if you suspect a cataract, but do not come to the conclusion yourself.

Luckily with cataracts - unless they progress and become larger - your dog will not feel its effects. In more advanced cases the following symptoms will be present:

• Blindness: This will manifest in your dog walking into furniture, having trouble with stairs and being startled by noises.
• Cloudy eyes: This is the signature symptom of cataracts but it can also be misinterpreted. 
• Red, inflamed eyes: Uveitis is a complication/accompanying condition with cataracts and causes the eye to redden. 
• Increased thirst and panting: These symptoms are seen in diabetic dogs which is commonly associated with cataracts.
• Heightened confusion and aggression: Cataracts brought on by diabetes or trauma can suddenly diminish vision. Some dogs may react to this with fear and react aggressively.

While the cloudy appearance of the eyes is indicative of cataracts, it is not conclusive. Your vet may ask behavioural questions about your dog such as if there has been a tendency lately to walk into furniture, to sniff for food rather than looking at it, issues playing games and if the dog appears lost in darker conditions. 

If your dog has a history of diabetes or you suspect that it is a possibility, tell your vet. Your vet will likely conduct a thorough physical exam, take blood samples and order imaging tests if he suspects that an underlying cause is responsible for your dog’s vision loss. 

An electroretinogram, which looks at the functionality of the retina, may be conducted to check the severity and nature of the cataract. Further, if there is retinal damage then surgery to fix the cataract will rendered pointless as well. 

If the vet is able to see the retina on observation it is unlikely to be a cataract and nuclear sclerosis is the more likely explanation for the cloudiness.

Surgery is the treatment of choice if you and your vet decide to go ahead with it. If there is no retinal damage, the capsule holding the lens is soft and there isn’t much inflammation in the eye then surgery can be an option. Also, the health condition of your dog is an important consideration. In the case of diabetic dogs, it is important to ensure that the dog will be able to sustain the trauma of surgery and anaesthesia. 

• If the dog’s vision is not impaired and the cataract(s) is small enough, then no surgical intervention will be required either. 
• Phacoemulsification is a new technique wherein cataracts are dissolved using sound waves. The damaged parts of the lens are then sucked out and a replacement lens is put in. 
• Post surgery, the dog has to be monitored for bleeds and inflammation. An Elizabethan collar or a cone is necessary as it prevents scratching of the area. Further, anti-inflammatory eyedrops will be prescribed for at least three months to reduce the likelihood of glaucoma and uveitis. 
• If you decide not to choose surgery, the vet may prescribe anti-inflammatory eye drops. While no eye drops can get rid of cataracts, they can help the spread of infection within. Cataracts can dissolve and trigger an inflammatory reaction; anti-inflammatory eye drops can prevent this to an extent.

Diabetes often causes cataracts, so lifestyle changes such as a healthier diet and exercise can be preventative. If you do suspect cataracts, you must take your dog to the vet at the earliest since those that are detected earlier have a better prognosis.

Deciding against surgery is in many situations the right choice. If your dog gradually loses vision - which is not a given - it is important to remain supportive and put in a little extra effort to make life a little more comfortable for your furry friend. Move away furniture that your dog may run into and put protective barriers on stairs. Since a dog relies more on smell and hearing, it may not be as affected as you may think. Blind dogs can still live happy lives with support.