“It looks like I have my cataract back, is that possible?” This question was posed to me at the start of clinic one day. The answer was simple. No. Cataracts, once removed never return. This is because the man-made lens that replaces the eye’s natural lens will not cloud. Without injury or unforeseen cause, the new intraocular lens will remain centered and clear in the eye.
So why did the patient complain about her vision looking as if the cataract had come back? The answer is a bit more complicated, but not uncommon. The cloudy vision is due to a posterior capsular opacity, more commonly known as a secondary cataract.
What Is A Secondary Cataract?
It is called a secondary cataract for a reason. The symptoms mimic a natural cataract in that the vision will become blurry, hazy, and/or cloudy. In addition glare becomes as much of a problem, if not more, than it was before cataract surgery.
In the eye, the natural lens is housed in a small, clear bag call the posterior capsule. When a cataract surgery is preformed, the ophthalmic surgeon will remove the eye’s hardened, natural lens, leaving the capsular bag in the eye. The new man-made lens is then secured in front of the capsular bag. The posterior capsular bag is a lot like the human appendix in that it won’t hurt to remain in the body even though there is no longer a function for it. Like the appendix there is no reason for the surgeon to remove it at the time of the cataract surgery.
As time goes by the empty capsular bag tends to scar over. Since it is located behind the new lens, the now cloudy bag blocks some of the vision making it hazy and/or clouded. A secondary cataract may develop as early as a few months, to several years after cataract surgery. Each patient is different and often the rate of development can not be predicted.
Can A Secondary Cataract Be Removed?
Absolutely. The treatment of a secondary cataract is a quick, simple and painless procedure called a YAG laser capsulotomy. The laser is focused directly at the opacity, and with just a few applications of the laser the cloudy area is dispersed.
The idea of the dispersal into the eye worries a lot of patients, but remember that the capsular bag is harmless to the eye. The most common complaint of patients who have undergone the YAG laser treatment is the appearance of floaters. These floaters usually number between one and ten and typically settle out of sight within two weeks time.
As with all medical procedures there is a slight risk of complications, and the YAG laser is no different. While considered to be extremely safe, the YAG laser carries about a 1% risk of retinal detachment in the procedure eye. Even with such a small percentage of risk, it is important to get all information from the physician before committing to the treatment.
Will Everyone Who Undergoes Cataract Surgery Get a Secondary Cataract?
No. Not everyone who has cataract surgery will develop a posterior capsular opacity, and even some of those who do may not be bothered by it. Only about 20% of all post-operative cataract patients will develop a secondary cataract that will require a YAG laser as treatment.
It is important to remember that any change in vision could potentially be devastating to eyesight. Any changes or visual problems need to be addressed by a medical ophthalmologist as soon as possible. The good news for people who have had cataract surgery is that if a posterior capsular opacity, or secondary cataract, develops it can be treated and restore the clear vision the patient experienced right after the initial surgery.