Presbyopia

• Presbyopia or eyestrain is characterized by the difficulty of the lens to focus on objects.
• Loss of the ability to adapt occurs in everyone around the age of 45-50.
• Presbyopia can be corrected with the use of corrective lenses or, currently, by surgical methods.

The lens is a biconvex lens located in the front part of the eye that allows people to focus on objects so that they can see them clearly, regardless of their distance; the lens accommodates itself to be able to see near and far objects correctly. With age, the adaptive capacity of the lens decreases and makes people have less adaptive power to focus on nearby objects. When this happens it is said that the person suffers from presbyopia or tired eyesight.

How is it produced?

The ciliary muscles are responsible for stretching the lens or relaxing it so that the lens better adapts to the objects it focuses on depending on the distance. With age, the lens, which has a liquid component, dries out, thus losing its ability to adapt to precise focus to see objects, which is known as accommodation.

This process of loss of adaptability happens to all people around the age of 45-50 and causes them to not be able to focus well on nearby objects. The loss of capacity occurs progressively throughout life, but it is not until the fifth decade of life that this decrease in the adaptation of the lens is translated into symptoms.

Symptoms

The main symptom of presbyopia is the inability of the person to focus on nearby objects when before he could do so perfectly. There are difficulties in reading or looking at a screen, having to move the object to be observed away so that the eye can focus it correctly. At a greater distance, logically, the more difficult it is to be able to appreciate the objects in all their detail.

The fact of having to strain the eyes to focus on nearby objects can cause eye fatigue - hence the name tired eyesight - with a feeling of dizziness, or sometimes even watery eyes or an itchy sensation.

Patients with myopia and presbyopia may take longer to notice symptoms, since both pathologies compensate, making near vision not so affected in myopic patients. On the contrary, hyperopic patients will see worse due to the additional effect of their pathologies to focus on nearby objects.

Diagnosis

The initial diagnosis will be based on the complaint that the patient will report about the inability to focus on nearby objects when before he could do so normally.

When this clinic appears, the patient must go to his ophthalmologist, who will evaluate the refraction, the and will do an examination with the, all this to evaluate the loss of accommodation capacity of the lens and rule out other possible pathologies.

Treatment

The correction of presbyopia or eyestrain has been classically based on the use of corrective lenses to be able to focus properly on objects. In the case of myopia patients, bifocal or progressive lenses are often chosen, which allow a good focus from far and near depending on the point to which the view is directed through the lens.

There are also surgical methods to treat presbyopia, such as laser intervention or replacement of the lens by an intraocular lens (IOL).

There is no age limit for these interventions, which are performed on an outpatient basis with local anesthesia applied to the eye using eye drops and with a quick and painless postoperative period. Both eyes can be intervened in the same surgical act and it is not painful. In general, the correction of presbyopia does not compromise distant vision, although each patient should be evaluated for concomitant hyperopia, myopia or astigmatism.

The use of one technique or another will depend on each patient, assessing the age, the degree of presbyopia, the concomitant visual defects and the state of the lens. The main ones are the following:

• LASIK technique: it is the most common of those with lasers. The objective of the intervention is to achieve a multifocal corneal surface in such a way that the central part of the cornea allows near vision while the periphery of the same takes care of the vision at medium and long distance. The intervention lasts less than five minutes for each eye, the postoperative period can be somewhat annoying and vision recovers in 24-48 hours.
• Conductive keratoplasty: seeks to correct hyperopia caused by presbyopia. It is based on the use of radio microwaves that collide with precise points on the cornea, modeling its shape to restore near vision. The postoperative is quick and painless.
• INTRACOR technique: based on the use of a femtosecond laser that through micro-pulses creates a series of concentric intracorneal rings that give it shape and redistribute the forces that act to correct presbyopia. No superficial injury is caused, the postoperative period is painless and fast, and in 24 hours the patient can read closely again.
• Use of IOLs: as for the correction of cataracts, it has been extended in the treatment of presbyopia. The lens is replaced by an IOL that supplies its function. There are different types of lenses, monofocal, multifocal or accommodative. The multifocals allow the patient to see well both from near and far, while the accommodative ones allow small accommodating movements when performing near vision. In patients with monofocal IOLs, the INTRACOR technique can be applied to improve presbyopia. In the case of very large myopia or hyperopia, IOLs can be implanted without removing the lens.

Precautionary measures

Presbyopia or eyestrain is a degenerative process, so there are no preventive measures to avoid it. Given the difficulty to see objects up close in people in the fifth decade of life, it is important that they go to their ophthalmologist to have them evaluated.