WHAT IS A CATARACT?
Cataract is an eye disease in which the natural lens (crystalline lens) of the eye loses transparency. This natural lens is located immediately behind the pupil.
In a healthy young person, the lens is clear and elastic. Its transparency allows light rays to pass through it, forming images onto the retina. The elasticity turns the lens into a multifocal lens capable of focusing objects according to the distance that we are looking at them, similar to the function of a camera's objective.
Over the years the crystalline lens loses elasticity and a disorder, called presbyopia or "aging eye" that is usually corrected with reading glasses, appears.
The clouding of the crystalline (cataract), does not allow the light reach fully the retina and vision is gradually lost. This process cannot be corrected with reading glasses and eye drops that supposedly slow the evolution, have not proven effective.
The only final treatment for cataracts is surgery: the cloudy crystalline lens must be removed and replaced with an artificial lens (intraocular lens).
WHAT ARE THE SYMPTOMS OF CATARACTS?
When a cataract is forming, blurred vision and double vision may appear. Some cataracts cause a paradoxical situation like seeing better on cloudy days than on sunny days or making reading glasses redundant. In most cases, it is difficult to drive at night and often patients need repeated changes in the graduation of their eyeglasses.
As time goes by, the vision decreases and may even cause blindness if it is not treated at the right time. It can even affect the contralateral eye if breakage of the cataract with intrasacular release of its content occurs. In these cases, a serious pathology called "sympathetic ophthalmia" may appear.
WHAT IS THE BEST TIME FOR CATARACT SURGERY?
When decreased vision interferes with the patient's normal activities, it is time to have surgery. The other situation that requires surgery is when the eye has an increase of intraocular pressure or other complications associated with the progression of cataract; in these cases, even if the patient has some degree of vision that allows him/her to perform normal activities, we suggest to remove the cataract. Formerly, cataracts were not removed until the patient was practically blind.
Currently this attitude not only makes no sense, but also it can be hazardous. Surgery of a very advanced cataract is, in general, more complicated, increasing the risks of surgery.
Sometimes, we recommend surgery for merely refractive reasons: in high presbyopic, myopic or hyperopic patients, the implantation of an intraocular lens in place of their crystalline lens, not only allows them to improve their vision, but also to see without eyeglasses or contact lenses.
IS THERE A RISK DURING SURGERY?
All surgeries have some risk, especially when they are of intraocular nature. Currently the results of cataract surgery are excellent and the visual recovery is usually fast and satisfactory in the most of the cases. However, it is important to know that it is not possible to guarantee 100 per cent success; but we can take a maximum of preventive measures so that the probability of risk is very low, and if there is a complication, this can be solved without major consequences.
HOW IS SURGERY CARRIED OUT?
The current technique is called cataract phacoemulsification using ultrasonic energy to fragment it.
This technique removes the cataract through an incision of 2 or 3 mm, although in our Eye Clinic we have succeed to reduce the incision to 1 mm, thus surgical impact will significantly be less traumatic (video).
The opaque content of the cataract will be pulverized and vacuumed through an ultrasonic device, then the capsule will be transparent, empty and ready for placing inside an intraocular lens that replaces the natural lens (crystalline). Currently, there are intraocular lenses made of flexible materials, which allow inserting them through the small incision made at the start of surgery. The lens is deployed inside the transparent capsule replacing the natural lens. There are different types of lenses: monofocal lenses like crystal glasses for far vision and multifocal lenses for far and near vision. In recent years, a new type of lenses that try to emulate the physiological mechanism of the crystalline lens have appeared, they are called "pseudo-accommodative lenses," which offer better optical quality.
Surgery itself takes about ten minutes and is usually performed under topical anesthesia (anesthetic drops) and a soft sedation so that the patient is relaxed. In most cases it is not necessary to occlude the eye at the end of surgery and the patient can see with the operated eye upon leaving the operating room.
Visual recovery is very fast in any case. Patients may be able to obtain useful vision within few hours after surgery. However, during the days following surgery, visual capacity will improve gradually up to a maximum, usually 2 or 3 weeks after surgery.
WHAT ACTIVITIES CAN DEVELOP A PATIENT AFTER CATARACT SURGERY?
Patients can almost make normal life, even if their vision is not perfect yet. During the first few days, they should avoid exercises that involve sudden movements of the head. It is very important to avoid rubbing the eyes.
Patients can sleep in the position they like, only avoiding the first few days sleeping on their stomach.
Especially during the first few weeks, they should use sunglasses to stay outdoors; this not only will serve to protect the eye, but it will also prevent the eye's glare that normally appears after surgery.
REGARDING THE TREATMENT
- Wash hands thoroughly before putting any drops or ointment in the eye.
- If two types of eye drops or ointments are matched at the same time, it is sufficient to wait 3 minutes between both applications and put ointments at the end.
- Some eye drops should be stored in a refrigerator (it will be indicated on the product instructions).
HOW ARE EYE DROPS INSTILLED?
Tilt your head back, pull the lower lid down and apply a drop without touching the eye.
HOW IS AN OINTMENT APPLIED?
Tilt your head back, pull the lower lid down and place a little ointment "as a grain of rice." The first portion should be discarded each time the tube is opened.