Although cataract surgery is the process of cleaning the patient’s cloudy lens (cataract) and replacing it with an artificial lens, it is possible to completely or partially get rid of glasses after cataract surgery with developing technologies. Artificial lenses placed in the eye can be produced in a way that corrects the refractive errors of the patient, thanks to today’s technology. In fact, cataract surgery is recommended even for people who do not have cataracts after a certain age but do not want to use near or far glasses. (clear lens extraction).
refractive errors of the eye MIOPY, HYPERMETROPY and ASTIGMATISM. In precise measurements made before cataract surgery, the number of the artificial lens to be placed in the eye is determined. The aim of this is to get the number as close to zero as possible after the surgery and to reduce the addiction to glasses or to get rid of glasses if possible. Myopia and hyperopia of the patient can be eliminated to a great extent with the standard artificial lens placed in the eye according to precise measurements.
Standard lenses are single vision (monofocal) and usually focus only on distance vision. These lenses do not have the ability to see near. Although the patient can see at a distance clearly without glasses, his near vision is impaired and he must use close glasses. This is an extremely natural result of surgery. However, if full information is not given by the doctor before the operation, it may be perceived as an incomplete intervention by the patient. However, the patient has become a healthy individual who does not use remote glasses at the end of this surgery. Every healthy individual starts to use close glasses from the age of 40-45. This is not a disease condition, it is a natural consequence of aging. (like white hair). In summary, this is the result to be obtained with standard single vision lenses.
However, thanks to the technologies developed in recent years, it is possible for the patient to see both far and near without the need for glasses after cataract surgery. There are different methods for this purpose. One of them MONOVISION technique. For this reason, the dominant eye of the patient is reset by cataract surgery, while the non-dominant eye is mildly removed. (up to 1.0-1.5D) is left myopic. In this way, the patient’s dominant eye sees the distance clearly, while the non-dominant eye sees the near better. With this technique, the patient can do most of his daily work without the need for glasses. (use of mobile phone, reading labels in the market). However, there will still be a need for glasses for very clear and sharp vision both far and near.
Another method is into the eye during cataract surgery. MULTIFOCAL INTRA Ocular LENS is placed. Multifocal intraocular lenses consist of interlocking rings of different refraction, focused at close range such as reading distance, medium distance such as computer distance, and far away such as television distance. It is aimed to see all distances with the same lens. The cataract surgery technique is the same for multifocal lenses, just like standard lenses. Only the type of lens placed in the eye is different.
Which patients are suitable for multifocal lens?
Although multifocal lenses seem very advantageous in theory, they may not be suitable for every patient. Post-surgical spot lights (like lamp), halo formations around, compatibility problems at intermediate distances, scattering and glare in lights such as sunlight or car headlights. These complaints are mostly temporary and are expected to regress within 3 to 6 months. In some patients, these complaints may be permanent. developed in recent years trifocal lenses, it is reported that these complaints are alleviated, and especially distance problems are reduced.
The most important issue with multifocal lenses is patient selection.
Eligible patient criteria for the multifocal lens (although there is no definite indication, patients with better results):
- People who have a strong desire to get rid of glasses
- Not too critical, more ‘carefree’contacts
- Those who do not expect to see very sharp near and far
- Those with hyperopia or very high myopic refractive error
Patient criteria that can be considered negative for the multifocal lens (patients who may be dissatisfied, although not certain)
- Patients who do not worry much about using glasses after surgery and do not aim to get rid of glasses
- People who are too critical and have unrealistic expectations
- Those who expect very sharp near and far vision
- People who were previously nearsighted (these patients’ near vision is usually extremely good and the quality of vision with a multifocal lens may be below expectation)
- Those who have to drive at night and those who work in jobs that require a lot of work with computers
- Patients with problems in the visual center (yellow spot disease, macular edema due to diabetes)
Cataract surgery with a multifocal/trifocal lens is an extremely useful method with high patient satisfaction if the appropriate patient is selected. However, patient selection is an important factor here.
Cataract and astigmatism
The clear glass part of the eye called the cornea (like a watch glass) is the most important refractive medium of the eye. It is global in structure (similar to the surface of a soccer ball). If one axis is flatter than the other, astigmatism occurs. (similar to an American football). In fact, almost every eye has varying degrees of astigmatism, no cornea is like a perfectly spherical surface. It may be necessary to use glasses for astigmatism above a certain degree.
Roughly 0.75D (diopter)
In a cataract patient with astigmatism above , standard intraocular lenses placed during surgery do not provide a complete astigmatism correction. A certain amount of astigmatism remains after the surgery. If the patient does not want to use distance glasses, the standard lens fitted may not satisfy the patient. For this, it is necessary to use an astigmatic lens called a toric lens. These lenses are specially produced considering the patient’s eye measurements. For this, the doctor needs to discuss all possible alternatives with the patient.
A cataract patient fitted with a toric lens should know that he or she will be exempt from distance glasses, but will use near glasses.
The issue of astigmatism is also a problem for multifocal lenses. If there is an astigmatism above 0.75D, the visual performance will not be good with flat multifocal lenses. Both multifocal and toric (with astigmatism) lens should be preferred.
As you can see, it is possible to live without glasses after cataract surgery, but there are many different conditions and methods. First of all, the patient should have realistic expectations and know what he wants. The doctor should also inform the patient about the possible results and expectations.