Cataract is the clouding of the eye lens (the crystalline lens), a normally clear and powerful lens inside the eye. In France, approximately 570,000 people undergo cataract surgery each year. Surgery is currently the only effective treatment to improve vision once cataract has developed.
There are no alternative treatments: neither eye drops nor laser can cure an existing cataract. In advanced cases, cataract can even lead to blindness.
Cataracts are the leading cause of blindness worldwide, especially in developing countries where access to surgery is lacking. Tens of millions of people are waiting for surgery, but due to a lack of resources and medical personnel, many end up losing their sight permanently. That is why humanitarian missions are regularly organized, especially in Africa.
Surgery is considered when the clouding of the lens begins to interfere with daily life. The deterioration of vision is usually gradual, often starting with blurred distance vision, sometimes paradoxically followed by a temporary improvement in near vision without glasses.
The degree of discomfort varies from person to person. The decision to operate is therefore always taken in consultation between the ophthalmologist and the patient. Without surgery, the cataract gradually becomes denser, vision deteriorates further and can eventually even complicate the examination of the retina.
The operation itself is now very safe, with a success rate of over 99.5%.
The procedure:
Cataract surgery is usually performed under local anesthesia, by administering strong anesthetic eye drops.
Once the eye is numbed, a micro-incision of approximately 2.2 mm is made at the edge of the cornea. Through this opening, an ultrasound probe is used to crush the lens without damaging the posterior lens capsule — this is called phacoemulsification. The lens material is then removed and replaced with a flexible artificial lens (implant). This is folded and unfolded in place of the original lens. There are different types of implant lenses, depending on the patient's needs.
Nowadays, the femtosecond laser can also be used during the procedure. This laser makes extremely precise incisions, cuts open the capsule and fragments the lens, which requires less ultrasound energy. The use of this laser increases the precision of the procedure, although its importance is still being investigated.
Cataract secundair
In approximately 1 in 3 patients, a so-called secondary cataract develops after surgery, in which the remaining posterior lens capsule becomes cloudy. This is done deliberately to keep the implant in place, but can later lead to reduced vision or a hazy feeling.
This secondary cataract is easily treated with a YAG laser, during a consultation. After administering pupil-dilating drops, the cloudy capsule is burned open in a few seconds. The treatment is fast, painless and very safe.