Intraocular Lens Implants in Dogs

Cataract surgery has become very commonplace in humans to remove cataracts and restore eyesight in the affected eye(s), with the first successful implant occurring in 1949.  Today over 6 million humans undergo this surgery every year. However, the first intraocular lens implants (IOL) in dogs did not occur until 1991.  

Veterinary surgeons use intraocular lens implant surgery to successfully treat thousands of dogs for cataracts every year. Success rates have improved significantly and are now approximately 85 to 90 percent. Veterinary ophthalmologists typically use this type of surgery in dogs whose own lenses have hardened.

The procedure for replacing the lens in dogs is virtually identical to that used in humans. The process is completed in two stages. 

Phacoemulsification

During this phase of the surgery, the surgeon will use an ultrasonic handpiece that has a needle attached to it. The surgeon will insert a needle into the lens that vibrates at approximately 40,000 vibrations per second. The vibrations cause the cataract material to break up and the lens removed from the lens capsule via a tiny incision made by the surgeon at the top of the cornea. 

Intraocular Lens Implant 

Once the surgeon has been able to successfully remove the cataract, he will then replace it with an intraocular lens implant. The type of replacement lens, soft or hard, is determined by the ophthalmologist at the time of diagnosis based on certain criteria. Once the new lens is in place the incision will be closed using tiny absorbable stitches. Following completion, normal vision should be restored to the eye.  

It is important to note that this type of surgery is extremely delicate as the slightest amount of damage to the dog's eye structure can have disastrous results. The surgeon uses a general anesthesia to ensure the dog does not move and a high-power surgical microscope is used to perform the surgery to reduce the risk of complications. In the event that both eyes have cataracts, it is best to have both undergo surgery at the same time, especially in dogs who have diabetes. 

Once the IOL surgery is complete and the dog has fully recovered, their eyesight should be very close to normal. Bear in mind that since the dog's natural lens is being replaced with an artificial one, it is not possible to  restore their vision 100 percent. On top of this, dogs tend to suffer from more inflammation than humans and as such are prone to heavier scarring that can also affect how much of their vision they regain. 

This scarring, referred to as lens capsular opacification, can be significantly reduced through the use of an oral antioxidant supplement and anti-inflammatory medications. While laser treatment can reduce capsular opacity in humans, it does not work in dogs. Any opacity that develops in dogs cannot be medically treated or reversed. 

Once the surgery is performed, it is not possible for a cataract to form in the eye again, but some dogs may suffer from loss of vision as they age due to glaucoma, the formation of scar tissue, and/or retinal detachment. 

After the surgery is complete, the dog will remain under observation for several hours to allow the doctor to monitor their intraocular eye pressure. After a thorough examination of the dog's eyes, the owner will be able to take him or her home. The owner is given topical eye medications along with an oral antibiotic to aid in safe healing and a full recovery. 

The average cost of intraocular lens implants for dogs ranges from approximately $1,500 to $3,000 per eye. The final cost includes the entire surgical procedure including the anesthesia, surgery, and post-surgery recovery time. Like most medical procedures, the price can vary significantly from one veterinary ophthalmologist to another. 

Intraocular lens implant surgery is considered to be a relatively safe and straightforward surgical procedure, but as with any type of surgery, it is not without risk. However, if the dog's quality of life is being significantly affected by the loss of vision resulting from cataracts, this procedure may be recommended. 

However, veterinary ophthalmologists agree that it is better to have the surgery done in the early stages of the condition, as this offers a much higher chance of success with a full recovery. The reason for this is that the older the cataract is, the harder it is to remove using phacoemulsification. Older cataracts can also cause significant intraocular inflammation, increasing the risk of complications that can cause loss of visual acuity. Finally, as the cataract ages, it can lead to calcification of the outer lens capsule which makes the surgery more difficult and also may result in decreased vision following the surgery. 

There are a few things that can be done to reduce the risk of degenerative eye disorders such as cataracts in dogs. The most important of these is to keep the dog at a healthy weight to ensure they do not develop diabetes. While it is important for the dog to receive the required medication, over-medication can cause complications including the formation of cataracts. 

Feeding the dog a diet rich in antioxidants including vitamins C and E have also been found to help reduce the risk of cataracts and nuclear sclerosis. 

Regular check-ups by a qualified veterinarian may not help to prevent cataracts, but early detection and treatment, including intraocular lens implants, offers the highest potential for success.