Farsightedness is a vision defect that occurs when the eye focuses light behind the retina.
The lens changes its thickness (it becomes larger or more rounded) to focus the light on the retina.
This process of natural correction is called accommodation .
People with farsightedness often have no symptoms due to defect compensation.
However, if they can not completely accommodate and therefore the light is not focused correctly, the vision is blurred.
This is because:
- The eyeball is very short,
- The cornea is very flat,
- The lens is not rounded enough.
Farsightedness allows you to see objects clearly when they are far away, but the near objects are not displayed correctly.
Other visual defects:
- The Myopia is a refractive defect characterized by focus images later on the retina, so the person does not see well from afar.
- The astigmatism is a visual disorder in which the cornea (transparent structure covering the front of the eye) is deformed.
Hypermetropia can be
- Unilateral (one eye only)
- Bilateral (both eyes).
- 1 What is the normal structure of the eye?
- 2 Types of hypermetropia
- 3 Causes of hypermetropia
- 4 What are the symptoms of farsightedness? How does it appear?
- 5 Diagnosis of hypermetropia
- 6 Treatment for hyperopia and laser surgery
- 7 Laser surgery
- 8 What is the difference between LASIK, LASEK?
- 9 Implantation of intraocular lenses for the correction of hyperopia
What is the normal structure of the eye?
The eye is composed of several parts:
- A front for focusing on the back of the eye ( cornea and lens ).
- A layer of light-sensitive cells at the back of the eye ( retina ).
- A communication channel for the brain ( optic nerve ).
- The light passes through an orifice called a pupil .
- A colored diaphragm in the form of a circle called the iris that surrounds the pupil.
The light is focused on the back of the eye through the lens.
A small layer of light-sensitive cells (photoreceptors) is located at the back of the eye.
The photoreceptors collect information from the visual field and form a thin film called the retina.
Each photoreceptor sends very fine signals to the brain.
The “electrical cables” that attach each eye to the brain are the optic nerves.
Types of hypermetropia
There are three types:
1. Congenital hypermetropia,
2. Simple hypermethropy,
3. Acquired hypothermia.
If there are no birth defects, the visual system works properly, but the child’s vision is limited to outline shapes and lights.
That’s because she has a strong farsightedness. The healthy babies have a farsightedness of at least 4 diopters .
This is physiological and is due to a number of factors, including poor coordination of the eye muscles.
Farsightedness in infants, children and adolescents up to the age of 15 is usually physiological because it is linked to the growth of the eyeball.
As the child grows, the length of the eyeball increases and farsightedness usually passes when the eyeball is fully developed.
Simple hyperopia is divided into:
- Axial : The eyeball is shorter than normal.
- Refractive : the lens has a reduced refractive index,
- Of curvature : if the cornea has a smaller curvature,
- Relationship (between the cornea and the lens): if the lens is more back than normal.
Acquired or pathological
hypermetropia Acquired or pathological hypermetropia is due to:
- Anomalies of ocular structures,
Another possible cause of acquired hypermetropia may be removal of the lens during cataract surgery .
In these cases, in general, farsightedness is temporary and passes when the disease ends.
Acquired hyperopia can occur after severe trauma that weakens the structure of the eye.
Classification based on correction of hyperopia
- Optional : the degree of hyperopia that can be corrected by accommodation. This value changes according to the accommodation capacity of the eye.
- Absolute : the part of hypermetropia that can not be corrected by accommodation.
- Manifesta – results from a refractive examination without the use of drugs that reduce the capacity of accommodation. It is the sum of absolute and optional hyperopia.
- Latent – is seen only in case of accommodation limitation caused by atropine eye drops.
In hyperopia total é a sum of these latent hyperopia + manifest.
Causes of hypermetropia
Generally, the causes of hypermetropia are genetic.
Farsightedness can occur at any age, but it tends to become more evident after 40 years.
In rare cases, hyperopia is caused by other diseases such as:
- Microftalmia (small eye syndrome, smaller than normal),
- Eye cancer.
What are the symptoms of farsightedness? How does it appear?
We young people it is possible that there is no symptom.
With age the symptoms can be:
- Tired eyes
- Burning in the eyes when looking closely
- Pain in the eyes after reading, writing, working with the computer,
- Eyes red and dry ,
- Hypersensitivity to light ,
- Vision blurred up close because of the difficulty of focusing,
- Reduction of distance vision in subjects with high hyperopia,
- Convergent strabismus in children,
- Lazy eye (amblyopia) in unilateral hyperopia.
With age, hyperopia tends to worsen.
In adults and the elderly, usually after 40 years of age, close accommodation capacity is not reduced, this is due to presbyopia (difficulty in focusing on nearby objects because of lens stiffening).
Diagnosis of hypermetropia
The ophthalmologist may diagnose farsightedness during the full eye examination of the eye.
The level of hyperopia is measured in diopters.
1. Mild hyperopia is between zero and two diopters (+2).
2. Moderate hyperopia is between 2 (+2) and 5 dioptrias (+5).
3. Severe or elevated hyperopia is greater than 5 dioptrias (+5).
Treatment for hyperopia and laser surgery
According to conventional medicine, hyperopia can be corrected with:
- Contact lenses,
- Refractive surgery with laser .
The natural medicine does not recommend lenses and surgery because the eye gets used to not work, then the muscles and nerves become atrophied (weaken).
The consequence is a further loss of vision .
According to Shelton’s hygienism , hyperopia can regress with the following natural remedies :
- The fasting , in his experience has cured many people,
- The exercises of visual rehabilitation to improve coordination of the eye muscles.
The outdoor life is important to accustom the eyes to look away, in fact, overwork on the computer or books can aggravate the refractive defects.
The use of glasses or contact lenses for a few hours a day is not recommended because when you take them you see a decrease of the view.
The surgery with LASIK technique can be done to treat:
The LASIK technique alters the shape of the cornea to improve light focusing or refraction of the eye.
LASIK is the procedure chosen for most people if they are appropriate.
- It is almost painless ,
- It allows a very fast visual recovery ,
- Both eyes can be treated in a single session,
During the LASIK procedure,
- First a thin layer of the cornea is raised.
- The machine then sends high-energy laser beams to reshape the cornea.
- After reshaping the fabric, the flap is placed back in its original position.
- Recovery times are rapid and suturing is not necessary.
Most patients undergoing laser surgery are very satisfied with the daytime view, but it is possible to have a worse night vision .
The reason is that all lasers have less effects on the peripheral area of the cornea and an oval shape causes a greater chaining at night.
New laser technologies compensate for this deficiency by increasing the number of shots on the periphery to create a more appropriate shape.
This allows for better night vision.
LASEK and PRK are other surgical techniques that can be used for myopia, hyperopia, presbyopia and astigmatism.
If the cornea is too thin, LASIK laser surgery becomes impossible because there remains too little residual thickness in the cornea.
In this case, the LASEK technique is recommended, which saves the corneal thickness.
The surgeon lifts a flap of epithelium (the thin layer of cells covering the surface of the cornea) and wraps it gently on one side to facilitate laser treatment.
The LASEK technique acts more on the surface: 50 microns below the surface, while LASIK acts at 160 microns from the surface.
We should remember that the higher the refraction, the more tissue needs to be removed.
Therefore, there are cases where LASIK is not possible because of the thickness of the existing cornea and the amount of tissue to be removed.
What is the difference between LASIK, LASEK?
The procedures are very similar, but LASEK:
- It does not cause a feeling of pressure during surgery.
- Lasts about 10 minutes for each eye.
- A soft contact lens is placed in the eye and should be maintained for 4 or 5 days after the operation, even at night, in bed.
- The first day after the surgery feels a little discomfort and this improves constantly, to the point that on the 3rd postoperative day, the eye is already almost asymptomatic.
- It takes more time to fully recover the vision.
With LASIK, the view is very good already from the next day.
With LASEK, the view needs more time to be recovered .
- After five days the contact lens is removed and the view is approximately 80% compared to that end.
The final visual acuity is reached about 1 month after surgery , even though the vision continues to improve for 6 months.
Implantation of intraocular lenses for the correction of hyperopia
This system can be used to treat myopia, hyperopia, astigmatism and presbyopia.
- The surgery is performed under local anesthesia (topical) and lasts for about fifteen minutes.
- The operation of insertion of intraocular lenses is performed on a day-hospital basis , after finishing the patient can return home.
- The surgeon makes a very small incision in the cornea and places the lens inside the eye.
This lens should remain in the eye forever.
- The patient has no pain during surgery, results are evident from the early days and patients are very satisfied with the operation.
- If necessary the lens can be removed , especially if the patient develops the cataract .
During surgery to remove the cataract, you must remove the lens and replace the lens to give the patient a clear view again.