The human eye has a clear crystalline lens designed to allow light rays entering the eye to focus on a point on the retina called macula. From the information, visual information is sent to the brain where it is processed, enabling us the see the image. The lens is located behind the pupil, the black central circle of all human eyes. Because it is clear, the crystalline lens can only be seen with a type of microscope called slit lamp.
When this natural lens begins to opacify, it is called “cataract”. Cataracts usually start in people over 60 years of age because, with aging, the core of the lens hardens, losing transparency. However, there are certain diseases or conditions that may promote early cataract development such as radiation, diabetes, trauma, and certain medications like steroids. Cataracts may also be congenital, meaning that the person is born with them.

Cataract surgery implies an incision, the opaque lens extraction and the insertion in its place of an artificial Lens. The actual and most efficient surgical technique is known as Phacoemulsification.

Cataracts are the primary cause of poor vision in adults. It is believed that there are 25 million blind people, and 110 visually impaired in the world as a result of cataracts. Close to two thirds of the world’s population over 60 suffer from cataracts. Today, cataracts may be readily removed by modern methods, improving low vision in 90 per cent of cases. There are no medical or nutritional treatments that may promote the recovery of the crystalline lens. This means to say that there are no eye drops, vitamins or special diets considered effective to improve the transparency of the lens. The only solution is surgery.

Before performing surgery, a complete examination of the eye is required, including special tests to determine the power of the artificial lens required in each individual case. Retinal examination is required in order to make sure that the retina, found in the posterior part of the eye and which, as explained before, is responsible for transmitting visual information to the brain, is healthy. If the retina is not well, even if the cataract surgery is successful, vision will not be good. Other general tests are required in order to make sure that the patient is in the best possible condition for surgery. For example, blood sugar levels need to be very well controlled in order for a diabetic patient to undergo surgery.

Most cataract surgeries are performed under local or topical (eye drops only) anesthesia. The surgeon and the anesthesiologist select the type of anesthesia, with the patient’s approval.

Cataract surgery results are excellent: the recovery of vision is fast and there is no pain during the post-operative period. After surgery, the patient is required to use anti-inflammatory and antibiotic eye drops, and eye protection at night in order to avoid involuntary trauma. Rubbing of the eyes must be avoided at all times. In the event of a residual refractive defect, Eyeglasses for reading will have to be prescribed even if multifocal intraocular lenses have been used. Multifocal intraocular lenses are used in special circumstances depending on the surgeon’s evaluation.

As with all procedures, unforeseen events or complications may arise during or after surgery. Physicians that perform cataract surgery are trained ophthalmologists whose main concern is to look after the wellbeing of their patients. However, there may be situations where the intraocular lens cannot be inserted because the supporting cataract capsule breaks, although such an event is rare. It may also happen that there is a loss of vitreous humor – the gelatin-type substance found in the posterior portion of the eye – leading to retinal inflammation that affects visual recovery. Complications such as bleeding or intraocular infections are very dangerous and compromise the fate of the eye, although their incidence is very low with the modern techniques used. Other complications such as corneal edema or inflammation are usually transient and may improve with medical treatment. Sometimes, certain complications may require one or more additional operations.