An after-cataract is the most common complication of modern cataract surgery, occurring in about 20 to 25% of cases. It is also known as posterior capsule opacification. However, it is not a real cataract because once a cataract has been removed, it does not recur. Unlike most other complications, an after-cataract occurs months to years following cataract surgery.
An after-cataract occurs when the back portion of the lens capsule becomes cloudy. This layer, also known as the posterior lens capsule, is normally retained during cataract surgery to support an artificial lens implant and to prevent the vitreous gel in the back part of the eye from entering the front part of the eye.
During cataract surgery, your eye surgeon makes every attempt to maintain the integrity of the posterior lens capsule while removing as many lens cells as possible from the lens capsule. However, it is impossible for any surgeon to completely remove all the lens cells from the lens capsule. As part of the healing response, residual lens cells left behind after the surgery migrate to the posterior lens capsule and multiply on the capsule. Over time, proliferation of these lens cells on the posterior lens capsule causes the capsule to become cloudy, leading to blurring of vision.
An after-cataract occurs more commonly in younger individuals. Improvements in artificial lens implant design and materials as well as surgical techniques have reduced the risk of after-cataract development over the last few decades.
After-cataract has similar symptoms to cataract
- Gradual decrease in vision
- Difficulty with bright light
The usual treatment for after-cataract is a laser procedure known as ytrrium-aluminium-garnet (YAG) laser posterior capsulotomy. In YAG laser posterior capsulotomy, a special intense beam of light is used to create an opening in the centre of the cloudy posterior capsule. This clears an area for light to enter the eye.
YAG laser posterior capsulotomy is mostly performed as an outpatient or day surgery procedure. A special contact lens is placed on the eye to focus the laser beam after numbing eyedrops (topical anaesthesia) have been instilled onto the eye. The procedure is painless and no incision is made in the eyewall. No special preoperative preparation or fasting is necessary.
YAG laser posterior capsulotomy is relatively safe, quick and simple. Patients may resume normal activities almost immediately after the procedure. In addition, most patients notice improvement in their vision within a day. In patients who are uncooperative, such as children or mentally disabled adults, incisional surgery under general anesthesia may be required to treat after-cataract.
Although YAG laser posterior capsulotomy is a relatively safe procedure, it is associated with a small risk of complications. These complications include increased eye pressure, retinal tear, retinal detachment, swelling of the macula, pitting of the artificial lens implant and lens implant dislocation. Some patients may also report seeing floaters after YAG laser posterior capsulotomy.
Your eye doctor may prescribe anti-inflammatory and/or anti-infective eyedrops following the procedure to reduce the risk of complications. In addition, anti-glaucoma eyedrops may be prescribed to reduce the pressure in the eye.