The word “Cataract” means that the lens in the eye has become white. The lens in the eye allows light to travel through the eye and reach the retina (the light receptors of the eye).
Any opacity of the lens will decrease vision. The common presenting history includes gradual or sudden onset of visual problems. In most animals the onset is gradual, although some dogs affected by diabetes have a very sudden onset. Some dogs with a sudden onset also have marked inflammation (uveitis) in the eye; this type of inflammation is called lens-induced-uveitis and is due to protein leaking from the lens into the eye itself. If a pet has cataract and inflammation in the eye aggressive anti-inflammatory medications are necessary to control the inflammation.
Long standing intraocular inflammation may also result in cataract, this is especially the case in cats and horses.
Animals of all ages may develop a cataract. The general rule of thumb is that young dogs with cataract have inherited cataract, middle aged dogs with cataract may have cataract due to diabetes and older dogs with cataract typically have cataract due to age related lens changes. A few dogs develop cataract due to retinal disease such as retinal degeneration. If retinal disease is suspected, ultrasonography and/or ElectroRetinoGraphy (testing the function/electrical activity of the retina) may be required prior to scheduling cataract surgery.
If vision is decreased by cataract the only treatment is surgery. The surgical treatment involves removing the lens by phacoemulsification (ultrasound treatment). Depending on the case, surgery may be recommended in one or both eyes. In some patients a plastic lens (implant) may replace the lens we remove during surgery. Many dogs undergoing successful cataract surgery can be discharged with home care the same day as surgery is performed.
The possible complications after surgery include retinal detachment and glaucoma (high pressure in the eye) and these complications may lead to blindness. It is important, as an owner, that you realize cataract surgery is an elective (optional) procedure – something you elect to do for your pet – not something you must go ahead with. Should you have any further questions about cataract or cataract surgery please call our office and ask to speak to Dr. Clinton or Dr. Evans.