LONG SIGHTNEES

Hyperopia or Long sightedness, is a common vision problem, affecting almost a fourth of the population. People with hyperopia can see distant objects clearly but have difficulty seeing objects that are near.

Long sightedness or hyperopia, occurs if a persons eyeball is too short or when the cornea is too flat when compared to the normal eye. The light entering the eye focuses behind the retina, instead of directly on it hence close objects look blurred.

Young people with mild to moderate hyperopia are often able to see clearly because their eyes can adjust, or accommodate to increase the eye's focusing ability. However, at later years the eye gradually loses the ability to accommodate and blurred vision becomes more apparent. 

Treating long-sightedness 

The most common treatment for long-sightedness is the correction of your eyesight using glasses or contact lenses. Laser surgery to correct long-sightedness is also becoming increasingly popular.

Glasses

Long-sightedness can usually be corrected using glasses made specifically to your prescription. Convex (thinner at the edge than at the centre) lenses are used to correct long sight. The curvature of the lens, its thickness and weight will depend on how long-sighted you are. Wearing a lens made to your prescription will ensure that light rays fall onto your retina and you can focus accurately.
The lens of the eye becomes less flexible with age, so you may need to increase the strength of your prescription as you get older. If you are both long- and short-sighted, you may need to wear two different pairs of glasses. Alternatively, some people use varifocal or bifocal lenses to see objects clearly that are both close up and far away.

Contact lenses

Contact lenses can also be used to correct vision in the same way as glasses. People often prefer contact lenses to glasses as they are lightweight and almost totally invisible.
There are two types of contact lenses available:

• rigid gas-permeable
• soft

However, there are many different lens materials and designs. Lenses can be worn on a daily basis and discarded each day (daily disposables) or disinfected and re-used, or worn for a longer period of time and kept in overnight. Your optometrist can advise you on the most suitable lens for you.
If you choose to wear contact lenses, it is important to maintain good lens hygiene to prevent eye infections developing.

Surgical treatment

A number of surgical techniques have been developed to treat long-sightedness. The most reliable uses laser surgery.
Surgical treatment for long-sightedness involves increasing the curve of the cornea to increase its focusing power. This is done by removing some tissue from the edge of the cornea.
The benefit of laser surgery over traditional surgery is that instruments do not have to enter the eye and the risk of damage or infection in the eye is much lower.
There are three main types of laser surgery:

Photorefractive keratectomy (PRK) 

A small amount of the surface of the cornea is removed, and a laser is then used to remove tissue and change the shape of the cornea. The amount removed depends on how poor your eyesight is and is controlled by a computer. The surface of the cornea is then left to heal.

Laser epithelial keratomileusis (LASEK)

This is a similar procedure to PRK, but involves using alcohol to loosen the surface of the cornea before it is lifted out of the way. A laser is then used to change the shape of the cornea, as with PRK. Once the treatment is finished, the surface of the cornea is put back into place and kept in place by natural suction.

Laser in situ keratectomy (LASIK)

This is similar to LASEK, but only a small flap of the cornea is involved. An instrument is used to cut a flap in the surface of the cornea, which is then folded back rather than removed, and a laser is used to change the shape of the cornea. When the laser work is finished, the flap is folded back down to its original position and kept in place by natural suction.

The laser surgery operation

Laser surgery is typically done on an outpatient basis. This means you will not have to spend time overnight in hospital, but will have one or more appointments at a clinic. The treatment takes around 30 minutes to an hour.
LASIK is normally the preferred method as it causes almost no pain and your vision recovers within one to two days. However, you may experience some fluctuations in your vision after this. It can take up to a month for your vision to stabilise entirely and for you to feel the full benefits of the operation.
LASIK treatment can only be carried out if your cornea is thick enough. If your cornea is thin, there is too great a risk of complications and side effects, such as loss of vision.
LASEK and PRK may be possible if your cornea is not thick enough for LASIK surgery. Recovery time tends to be longer using these techniques; it can take up to six months for your vision to stabilise after PRK surgery.

Who cannot have laser surgery

You should not receive any sort of laser surgery if you are under 21 because your vision will still be changing and it would be dangerous to alter the structures of your eyes at this stage.
Your vision can also change if you are over 21. Your clinic should check your glasses or contact lens prescriptions to confirm that your vision has not changed significantly over the last two years.
Laser surgery may also not be suitable if you:

• Have diabetes. This can cause abnormalities in the eyes that can be made worse by laser surgery to the cornea.
• Are pregnant or breastfeeding. Your body will contain hormones that cause slight fluctuations in your eyesight and focusing power, making precise surgery too difficult
• Have a condition that affects your immune system, such as HIV or rheumatoid arthritis. This may affect your ability to recover after surgery.
• Have other problems with your eyes such as glaucoma (a condition that can cause blindness) or cataracts (where the lenses of the eye harden and become cloudy).

Risks of laser surgery

As with all surgical procedures, laser surgery carries some risks. Possible complications of laser surgery are outlined below.

• Following surgery, your vision may get worse if the surgeon misjudges the amount of tissue taken from your cornea (this is known as a correction error).
• The flap cut into your cornea begins to grow into the main part of the cornea when replaced (this is known as epithelial in-growth, which can cause problems with your vision and may require further surgery to correct).
• Your cornea becomes too thin and your vision is reduced or lost (this is called ectasia).
• Your cornea becomes infected (known as microbial keratitis).

 

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