Can surgery be performed for presbyopia

After reaching middle age or old age, people's vision begins to decline and they are more likely to develop presbyopia. The best way to treat presbyopia is to wear glasses, and the same is true for myopia. However, myopia can now be solved through surgery, which saves the trouble of wearing glasses. When facing presbyopia, many people also hope to undergo surgical treatment. So, can surgery be performed on presbyopia? Let’s take a look below.

Currently, there are three main types of presbyopia surgery:

1. Subjectively shaping mild "myopia":

The myopia treatment procedure using excimer laser is to perform "under-correction" surgery on patients who already have myopia and presbyopia, that is, retain mild myopia so that the patient has a certain near vision.

The hyperopia treatment procedure using excimer laser is to combine the original hyperopia with presbyopia and perform "overcorrection" surgery, so that the patient retains mild myopia and has a certain near vision.

The disadvantages of this surgical method: Although it improves the patient's near vision, because the refractive state is myopia, the visual effect for distance vision is sacrificed. For those patients with long-term, high-degree myopia, or those who do not have high requirements for distance vision, it is relatively acceptable. The vast majority of patients are still quite resistant to the decline in their ability to see far.

2. Monovision surgery:

This surgery is designed for patients who require both far and near vision. This type of surgery is generally only used for patients with both myopia and presbyopia.

Principle of surgical design: Before the operation, the patient's "dominant eye" and "non-dominant eye" need to be determined first. During the operation, the myopia of the dominant eye will be completely corrected so that the dominant eye can be used to see far away. Then the myopia of the non-dominant eye is "under-corrected", leaving a small amount of myopia for close vision. Normally, after a period of adaptation, the visual center of the brain can adjust itself to use both eyes to see objects at different distances.

Points to note: Not everyone can adapt to this imbalanced state after surgery. Some people will experience obvious visual interference symptoms such as dizziness and eye swelling once the refractive states of their eyes are different (anisometropia). Therefore, patients who are preparing to undergo this surgical method need to wear frame glasses or contact lenses for a week before the operation to make one eye "adequately corrected" and the other eye "undercorrected" to determine whether the patient can adapt to this "unbalanced" state.

Disadvantages of this surgical method: How much myopia should the "non-dominant eye" retain to be most appropriate for the patient's near vision ability? The general principle is: retain 100 degrees at the age of 45, 200 degrees at the age of 50, and 300 degrees at the age of 55. However, this is not suitable for all patients because the degree of decline in accommodation ability after presbyopia is not the same for each person.

Another point is that the eyes cannot work together after the operation, especially in dim light or when the work done requires a high degree of balanced vision.

Third, because of the unbalanced vision of both eyes, it is more likely to have visual quality problems such as glare, poor contrast sensitivity, decreased sense of spatial distance, phantoms, double vision, etc. when driving or using the eyes at night.

3. Wavefront-guided multifocal cutting method:

Excimer laser multifocal ablation surgery is suitable for patients with both hyperopia and presbyopia. It is currently considered the best binocular presbyopia correction surgery. It can reasonably solve the patient's visual problems in looking at near, far, and intermediate-distance objects, while preserving the patient's binocular vision.

Limitations of this surgical method: Multifocal ablation must be performed under the guidance of wavefront aberration. Although wavefront-guided multifocal ablation presbyopia surgery is currently the best method and has been approved by the US FDA and has been carried out smoothly abroad, this type of surgery still has some problems. If these problems are not properly resolved, it will have a certain impact on patients' expectations and surgical results.

1. Sacrificing the patient's visual quality for long and medium distance vision: Presbyopia surgery uses laser to cut multiple focal points on the cornea to create an aspherical curve to widen the focal depth (depth of field) of the field of vision. This surgical method also requires the patient to make necessary sacrifices in far and medium distance vision. Therefore, while the near vision is significantly improved after the operation, the far and medium distance vision will inevitably be slightly lower than before the operation.

2. Stability of surgical results: Myopia is basically in a stable state at a certain age (after 18 years old), while presbyopia is in a state of continuous development. Therefore, it is very difficult to require the stability of presbyopia after surgery to be the same as that of myopia. Presbyopia surgery is not a one-time operation. It can only reduce or delay the need and time for patients over 45 years old to use reading glasses. The patient's near vision can be significantly improved in the short term after surgery, but as the patient continues to age, presbyopia will reappear.

In addition, according to doctors who perform multifocal ablation surgery: Generally speaking, for patients with simple presbyopia or hyperopia combined with presbyopia, if they have been wearing reading glasses of appropriate degrees, this type of patient will benefit best from multifocal ablation surgery. However, for patients with myopia and presbyopia who have never worn reading glasses, the improvement in near vision after surgery is not as great as that of the previous group of patients.

3. Impact on cataract surgery: As patients undergoing presbyopia surgery, due to their age, they need to consider the problem of cataracts in old age. If cataract surgery is needed in the future, special care must be taken when implanting an artificial lens. Multifocal artificial lenses cannot be implanted, otherwise there will be an overlap and conflict between the multifocals on the cornea and the multifocals of the artificial lens.

4. Side effects of multifocals: Multifocal cutting technology itself has certain side effects, including a slight decrease in contrast sensitivity, night vision syndrome, and the generation of spherical aberration.