High myopia

Myopia is a condition that occurs when, in eyes that are larger than normal, images are focused in front of the retina and not on it. This results in blurred vision at far distances and a significant decrease in visual acuity.

We speak of high myopia when a patient has more than 6 diopters. This type of myopia is associated with even longer eyes, that is, with a very long axial length. It is also considered high myopia if the patient has an anteroposterior axis greater than 26mm.

This type of myopia currently affects 2% of the population and continues to increase in developed countries, although the causes have not been determined. High myopia, which usually appears during childhood and stabilizes between 20 and 30 years of age, can cause legal blindness in the most severe cases.

This refractive defect poses a risk to vision as it can lead to more severe visual pathologies.

What is high myopia?

In this type of disorder, the more diopters increase, the more the eye lengthens (axial length) and the greater the risk of associated visual disorders.

Some of these disorders may include:

• Retinal detachment; patients with myopia greater than 5 diopters have a 10 times higher risk of this type of detachment. When this occurs, the patient usually presents luminous flashes, flying flies, visual field defects such as seeing a black curtain and even total loss of vision.
• Glaucoma; myopia is not a direct cause of glaucoma, but it can be a risk factor for developing this pathology. Myopic patients should be aware that, even if they have undergone refractive surgery, the risk of glaucoma still exists.
• High myopia can favor progressive retinal and choroidal atrophy, vitreous degeneration, optic nerve alterations, retinal hemorrhages and even macular holes.
• Cataract; this type of disorder tends to develop earlier in patients who present high myopia.

Treatment

In principle, there is no specific treatment for high myopia and, in any case, an individual assessment of each patient should be made to establish the guidelines to be followed.

Blurred vision, or refractive error, can be corrected by the use of contact lenses and/or correction with glasses. Also, vision correction can be performed by undergoing refractive surgery for myopia with LASIK laser.

There is also the possibility of implanting intraocular lenses (ICL type phakic lenses), which consists of implanting a lens between the iris and the crystalline lens. This technique is reversible and preserves the cornea in its natural state.

Myopia surgery is performed on an outpatient basis, meaning that the patient is not hospitalized.

Prevention

Until recently, there was no effective method to slow the progression of myopia. Recently, studies in children have shown that orthokeratology and treatment with low-dose atropine eye drops are the only treatments that succeed in slowing its progression.

On the other hand, the resulting complications can also be treated. Good ophthalmologic follow-up is of vital importance.

That is to say, vision controls should be performed periodically to facilitate the diagnosis and treatment of visual disorders associated with high myopia. Early diagnosis of these complications will allow us to minimize vision loss.

Likewise, it is important to remember that refractive surgery corrects vision, but does not prevent the disorders associated with this pathology from developing.