What is hypermetropia? This, in simple terms, farsightedness. Surely many are familiar with this violation of visual function. It is quite common, and therefore now it is necessary to talk about the causes of its occurrence, pathogenesis, the first symptoms, as well as the principles of diagnosis and treatment.
About the disease in brief
Approximately 40% of people have he althy eyes - those that can correctly refract light and further focus the image on the retina. This is also called refraction.
What is hypermetropia? A condition in which the image is focused directly behind the retina. This disorder occurs in approximately 30% of the population under 20 years of age. Usually two eyes are affected, but often the diopters are different in each.
As a rule, no special visual disturbances are observed at the initial stage. Therefore, patients learn about their diagnosis only after undergoing an examination by an ophthalmologist.
Reasons
So, what is hypermetropia, clearly. Because of whatdoes it arise? The reason lies in the fact that the power of the refractive apparatus simply does not correspond to the anterior-posterior size of the eye.
Why is that? With farsightedness, this occurs either due to a shortened axis of the eyeball, or due to a too weak refractive apparatus. Be that as it may, the result is the same, regardless of the cause - the refracted rays are not focused as they should.
It is also important to mention that some people suffering from this disease have insufficient optical power of the lens and cornea. And the longitudinal axis of the eyeball is also shortened.
About prerequisites
Hypermetropia of the eyes occurs behind the retina due to weak refraction and insufficient refractive power. There are certain reasons for this. Predisposing factors can be listed as follows:
- Injuries.
- Surgical interventions.
- Disturbances in the development of the visual apparatus.
- Short longitudinal axis of the eye.
- Slight curvature of the cornea.
- Hereditary predisposition (the parameters of the eyeball are taken into account).
- Tumours.
- Problems with blood supply to the retina.
The severity of farsightedness also depends on these factors.
There are more risk factors. If a person has diabetes mellitus, is over 40 years old, does not comply with the regime of work and rest, and also eats irrationally, is physically overloaded and regularly overworks the eyes, he may develop farsightedness.
Features of the disease
Tellingabout what hypermetropia is, it must be noted that physiologically it is present in newborns (from +2 to +4 diopters). All due to the fact that they have a small longitudinal size of the eyeball. Its length is a maximum of 17 mm.
More pronounced farsightedness is diagnosed with microphthalmos. This is the name of the reduction of the eyeball in size. This anomaly is usually combined with other pathologies, including:
- Cataract.
- Coloboma of the choroid and optic disc (OND).
- Predisposition to glaucoma.
- Lenticonus.
- Aniridia.
Also, the condition can be combined with anomalies of the toes, hands, ears, cleft palate and cleft lip.
Classification
It should be noted that there are different degrees of hypermetropia in children and adults. Also, this disease is classified according to the mechanism of development. Allocate axial and axial farsightedness. It can also be hidden if a person compensates for his anomaly with the help of accommodation tension.
Also, farsightedness is classified into congenital, age and natural physiological. And according to the degree of hypermetropia is divided as follows:
- Weak (up to +2 diopters).
- Medium (up to +5).
- High (more than +5).
Symptoms
Until moderate hypermetropia occurs, no signs of a person will be particularly disturbing. It simply strains accommodation, and therefore good vision is preserved. Yes, even with moderatefarsightedness, it is practically not broken. Only when working at close range, such manifestations are observed:
- Eye fatigue too quickly.
- Discomfort in the area of the eyebrows, bridge of the nose and forehead.
- Pain in the eyeballs.
- Visual discomfort.
- Feeling of merging letters and lines, vagueness.
- Experienced need to move away a little to look at some object, desire to add lighting.
At a high degree, others are added to these manifestations. The situation gets worse:
- Vision is reduced, both far and near.
- Asthenopic symptoms appear. Fatigue occurs almost instantly, the head hurts inexpressibly strongly, and the eyes seem to be bursting.
- OND borders become fuzzy, hyperemia is formed.
Also, farsightedness is often accompanied by chalazion, conjunctivitis, blepharitis, barley. This is because many people reflexively rub their eyes to relieve discomfort. And this is fraught with infection. In elderly people, by the way, hypermetropia is a provoking factor of glaucoma.
From farsightedness to nearsightedness
The child is growing, and hypermetropia (according to ICD-10 code - H52.0) passes. Because the eyeball grows to a normal size (about 23-25 mm).
Because of this, farsightedness disappears. A proportional refraction is formed. And then, as the growth of the eye progresses, many develop the exact opposite.phenomenon is myopia. It is also called myopia. If the growth of the eyeball is delayed, then mild hypermetropia begins to progress.
By the time the body finishes growing, about 50% of people have farsightedness. Others have either nearsightedness or normal vision, called emmetropia.
What happens with age?
It is not known exactly what causes the eyeball to lag behind in growth. However, many farsighted people fully compensate for their inherent weakness of refraction. They constantly strain the ciliary muscle of the eye, thereby holding the lens in a convex state. So its refractive power increases.
But then the ability to accommodate decreases. Approximately by the age of 60, people who suffered from hypermetropia (see above for the ICD-10 code) exhaust their compensatory capabilities. Because of this, the clarity of vision steadily decreases. And both far and near.
There is a development of senile farsightedness, more correctly called presbyopia. It is characterized by the inability of a person to consider some small objects or read tiny letters at close range. With such a pathology, vision can be restored only through the use of glasses on which converging lenses are installed.
Diagnosis
Farsightedness is determined by an ophthalmologist during a routine visual acuity test. Everyone is familiar with visometry - a method that involves diagnosing a violation using special tables. In the case of farsighted patientscarry it out without correction. The use of plus lenses is not necessary in this case.
Also mandatory is the study of refraction. For this, there is a computer refractometry, as well as skiascopy.
To reveal latent hypermetropia, procedures should be carried out under conditions of mydriasis and cycloplegia. It's simple: atropine sulfate is instilled into a person's eyes.
But to examine the anterior-posterior axis of the eyeball, you will need echobiometry and ultrasound. It is imperative to identify whether any pathology accompanies farsightedness. Therefore, the patient will have to undergo such measures as biomicroscopy with a Goldman lens, perimetry, tonometry, ophthalmoscopy, gonioscopy, etc.
If a person has strabismus, a biometric study is performed.
Therapy
The most common treatment is conservative. It involves wearing contact lenses or glasses. Also, a person can be offered laser correction or surgery. Today, many operations are performed - hyperphakia, thermokeratoplasty, hyperartifakia, lensectomy, etc.
Treatment is not necessary if the person has no complaints and visual acuity does not deviate from +1 diopter.
Children of preschool age diagnosed with farsightedness greater than +3 are shown to wear glasses at all times. By the age of 6-7 they can be removed if there is no tendency to form amblyopia and strabismus.
Lenses and glasses are always selected, taking into account the accompanyingpathologies and individual characteristics of the organism. In some cases, if farsightedness does not exceed +3, so-called orthokeratological lenses are used for night wear. With severe hypermetropia, complex glasses are prescribed. Sometimes two pairs - for work at a long and close distance.
And they often recommend hardware treatment, physiotherapy, taking vitamins and biological supplements. It is recommended to watch TV with perforated glasses.
Hypermetropic astigmatism
This disease needs to be told separately. With it, there is no single focus of light rays on the retina, and the reason for this is the different radius of curvature of the optical systems of the eye.
Astigmatism combined with hypermetropia is an anomaly. It is either congenital or acquired. Corrections are very difficult. In addition, the phenomenon is quite rare. Most often, in children with hyperopic astigmatism, parents also suffer from this or another visual defect.
And the reasons for its formation are as follows:
- Inheritance by autosomal dominant type.
- Pathology of the lens. For example, cataract, pseudoexfoliative syndrome or coloboma.
- Corneal diseases, membrane damage (ulcer, cataract, endothelial dystrophy, keratitis).
- Iatrogenic intervention. If a surgical operation was performed on the eye, then due to the uneven tension of the sutures, the pathology in question may well develop.
- Injuries. Especially a penetrating wound. Due to injurydense scars and synechia are formed. And they deform the lens and cornea.
To the symptoms, in addition to those characteristic of farsightedness, there is a feeling of "sand" in the eyes, cramps and blurred vision. And working at a computer, spending time on gadgets and reading cause severe fatigue.
Often, patients complain of a headache that only gets worse in the evening. As a rule, discomfort is localized in the superciliary region.
If the astigmatism is pronounced, then the image that a person sees looks blurry, deformed. Sometimes there is pain and diplopia in the area around the eye sockets.
Complications of astigmatism
This is a very serious disease. Hypermetropia of both eyes, accompanied by astigmatism, often leads to asthenopia and strabismus. And if a child is sick with this disease, then meridional amblyopia cannot be avoided. With this pathology, visometric disorders can be noted only along certain meridians.
With age, the degree of the disease increases. In especially severe cases, there is a total decrease in visual acuity. And with the illiterate use of lenses in the epithelial layer, point defects can form, which later form entire areas of ulceration.
It is also worth remembering that people with this disease are at high risk of developing xerophthalmia.
Treatment
Tactics is selected with the obligatory consideration of the patient's age, as well as the degree of hypermetropia, combined withastigmatism. Here are some options:
- Mild to moderate disease in children can be corrected by prescription of glasses. But with a developed pathology, this will only lead to complications. Therefore, only toric and spherical rigid lenses can be used.
- Disease associated with high degree hypermetropia can be corrected with soft lenses. Also toric.
- Anyone over the age of 14 can wear both contact lenses and glasses.
Surgical treatment is indicated if all of the above tactics fail. The operation can be performed after 18-20 years - by this time the visual system is fully formed. There are several types of interventions:
- Arcuate keratotomy.
- Laser keratomileusis.
- Photorefractive Keratotomy.
- Toric IOL implantation.
The method is chosen individually. If you start treatment on time, then you can not only stop the deterioration of vision, but even completely restore the lost functions.
