CATARACT SURGERY INFORMATION
What are cataracts?
A cataract is an opacity or cloudiness that develops within the lens of the eye. The lens is a normally clear structure in the center of the eye that helps to focus light on the retina and allow for fine detail in vision. Therefore, when a cataract develops, it results in cloudy or blurred vision, and up to complete loss of vision.
Click on the questions below to learn more about cataracts and the issues that surround treatment.
Most cataracts in dogs form due to genetics (inherited cataracts). Cataracts can also result from systemic disease (diabetes mellitus), inflammation within the eye (uveitis), trauma, toxic or nutritional causes, and with advanced age (senile cataracts). Genetic cataracts are more common in certain breeds of dogs, including Boston Terriers, Poodles, American Cocker Spaniels, Schnauzers, and Siberian Huskies, as well as Labrador, Chesapeake Bay and Golden Retrievers, among others.
It is a common misconception that cataracts in older dogs should not undergo treatment. While some dogs can adapt to the blindness caused by their cataracts, many older dogs will benefit greatly from cataract removal, and are oftentimes reported to seem “younger” or “spunkier” after their vision is restored with surgery. It is also a common misconception that older dogs cannot undergo anesthesia. While we certainly have to be mindful to fully evaluate the dog for concurrent or age-related medical conditions, healthy older animals tend to tolerate anesthesia very well with only minor modifications in the anesthetic protocol. Therefore, there is no true age limit for cataract surgery in dogs.
If your pet has been diagnosed with cataracts and you would like to consider restoring his or her vision with cataract surgery, the next step is to have an evaluation performed by a board-certified veterinary ophthalmologist. During this examination, your pet will be evaluated for concurrent ocular disease that could prohibit him or her from having a successful cataract surgery, such as corneal disease, severe inflammation within the eyes (uveitis), or retinal disease (degeneration or detachment). We will use a combination of findings from the ocular examination, as well as additional diagnostics, including functional testing of the retinal (electroretinogram) and ocular ultrasound, to make this determination. Your pet’s total body health will also be assessed with a physical examination and with blood and urine screening tests (complete blood count, biochemical profile, urinalysis). If your pet is found to be a good ocular candidate for surgery, and in sufficient overall health to undergo anesthesia, surgery will be recommended.
Any of the following changes could be an indication of a possible complication, and warrant evaluation.
- Increased redness or swelling of the eye(s)
- Increased discharge (especially green or yellow discharge)
- Increased cloudiness of the eye(s)
- Increased squinting or holding the eye(s) closed
- Scratching or pawing at the eye(s)
- Decreased vision
Please call if any of these changes are noted and we will schedule your pet for an evaluation as soon as possible.
Cataract surgery in dogs is actually very similar to cataract surgery in people. First, a small incision is made at the top part of the eye between the clear cornea and the white sclera. Then, the eye is entered and a small circular hole is made within the capsule of the lens. (Think of the lens like an M&M with an outer candy coating/capsule and an inner chocolate filling/lens protein). Ultrasound energy (or phacoemulsification) is then used to break up and suck out all of the abnormal cloudy lens proteins. The capsule is then polished, and an artificial acrylic lens is implanted within the natural lens capsule. Finally, the incision at the top of the eye is closed with very small suture material (approximately the thickness of a piece of human hair). Because the suture is so small and fragile, we ask the dog to wear an Elizabethan collar (E-collar, plastic cone) to prevent inadvertent trauma to the surgical site for the first 7-10 days following surgery.
The success rate for cataract surgery in dogs is quite high, with greater than 90% of cases undergoing a successful procedure and seeing better following surgery. This success rate is mildly reduced in some instances, such as hypermature cataracts, and more dramatically reduced in other instances, such as phacoclastic uveitis.
The main complications following cataract surgery include the development of glaucoma (or increased pressure in the eye), infection within the eye (endophthalmitis), or retinal detachment. Glaucoma occurs in roughly 5% of cases following surgery, and is typically managed with a short course of additional medical therapy to control pressure in the eye. Rarely, medications are ineffective to control the pressure, and an additional procedure (endolaser) will be recommended to control pressure on a more long term basis. The development of an infection within the eye or a retinal detachment can both be severe, vision-threatening complications, however we take every precaution to avoid these outcomes, and fortunately these possibilities occur in less than 1% of cases.
There is a fairly rigorous follow up routine after cataract surgery in dogs. The reason for this routine is to allow the best chance of detecting any potential complication at an early stage when treatment interventions can be effective to reverse the problem. In general, we will see the patient back the day following surgery, 1 week after surgery, then 2 weeks, 1 month, 3 months, and 6 months later, and then annually for life. We want the procedure to be a success for your pet just as much as you do, therefore, we include all recheck evaluations for the first month in the cost of the surgery, and ask that you call/bring in you pet for evaluation if there is ever any question as to how he or she is doing at home.
Informational brochure by Animal Vision Center of Virginia: