Dra. Daniela Barba Castelo | Ophthalmologist
Ametropia
Dra. Daniela Barba Castelo | Ophthalmologist
What is myopia?
Myopia is the most common refractive error, where the patient perceives distant objects blurry because the image is formed in front of the retina, either because the cornea, the lens or both are very powerful or because the eye is longer than normal.
Once the measurements of the eye are extreme (very long eye) it can lead the eye to a pathological state (pathological myopia) or the extreme measurements in the corneal curvature by making an extreme lens prescription.
Myopia can manifest itself from childhood and increase over the years, it is expected that myopia will stabilize at approximately 18 years of age, however there are cases in which it can continue to advance.
What is Astigmatism?
Astigmatism is a refractive error that is produced by irregularities in the curvature of the cornea, that is, it does not present the same curvature in all its areas.
When an eye has astigmatism, light from objects that enters the eye is focused on more than one point on the retina, causing blurred and distorted vision, since when an eye does not have refractive errors the image is focused on a single point of the retina.
Symptoms
The symptoms will manifest depending on the astigmatism that is suffered or the degree that it presents.
What is hyperopia?
Hyperopia is a refractive error where the patient perceives objects blurry both far and near, and this is due to the fact that the image is formed behind the retina. After a certain age these symptoms of blurred vision are exacerbated.
Hyperopia occurs in children because the size of the eyes are smaller but as the eye grows the graduation begins to stabilize, it is very important to detect these refractive errors at an early age to avoid amblyopia also known as lazy eye.
What is Presbyopia?
Presbyopia, which literally means "aging eye," is an age-related eye condition that makes it difficult to see things up close. It is a refractive problem that occurs when our natural lens called crystalline loses the ability to focus on nearby objects.
When you are young, the lens of the eye is soft and flexible. Over the years, it changes its shape so that it can focus on near and far objects.
After 40 years of age, the lens loses its elasticity and little by little it becomes more rigid.
This form that the lens takes, it can no longer change so easily and activities such as reading, reading the cell phone or nearby work become uncomfortable. This is what is called "presbyopia."
This elasticity is not lost suddenly, it is a process that is progressive and in a period of approximately 10 years, this elasticity is already lost; this is when the patient will need glasses for all nearby activities.
Since most people develop eyestrain in their 40s, it is important to know what other eye conditions such as myopia, hyperopia and astigmatism can be mixed with presbyopia. Patients who are myopia will have fewer problems with near vision from the eye condition.
If the patient does not want to wear lenses, this surgical treatment is the implantation of TRIFOCAL type intraocular lenses, this in order to make the patient independent of the lenses in a PERMANENT way.
It is a very effective and safe alternative, but the evaluation by the ophthalmologist is important to know if you are a candidate for it.
Among the most common symptoms are:
Blurry vision
Headache
Visual fatigue
Zoom in on objects to see
The characteristic symptom is blurred and distorted vision of both near and far objects; Difficulty with near vision may also occur.
Astigmatism can be genetically determined or it can be due to trauma or surgery. It can be presented:
Simple: that only affects one axis
Composite: associated with myopia or hyperopia
Mixed: one axis focuses in front of the retina and the other behind.
When the graduation is not very high, children have the ability to accommodate objects and may not show any symptoms, but the constant effort of accommodation can lead to headaches or visual fatigue.
In the case of adults over 40 years of age, presbyopia or also known as eyestrain occurs, in which it is a defect for near vision since the capacity for accommodation is lost.
Treatment
Currently there are various treatments to treat presbyopia, such as additive lenses, which will only be used exclusively for close tasks.
If the patient also suffers from ametropia (myopia, hyperopia or astigmatism) there are different types of lenses to correct 100% of the ocular condition either with bifocal or progressive lenses; it is important to know the patient's work activities to fit the correct lens.
If the patient does not want to wear lenses, there is the option of surgical treatment, which is the implantation of intraocular lenses of the TRIFOCAL type, this with the purpose of making the patient independent of the lenses in a PERMANENT way.
It is a very effective and safe alternative, but the evaluation by the ophthalmologist is important to know if you are a candidate for it.