Many of the world’s population are long sighted which means that nearby objects may appear blurred while those in the distance are clearer. In medical terms this condition is known as hyperopia and is usually treated by means of wearing glasses or contact lenses. However, increasingly individuals are opting for the convenience of one-off laser eye surgery which is often a good option to treat long sightedness.
Causes of long sightedness
Long sightedness can be a genetic condition but it also occurs with age in the general population (usually in those aged 45 and over). Those born with the condition tend to have shorter eyeballs that the rest of the population or the cornea is too flat, causing the light to enter the eye and focus on the retina in a particular way.
In some cases it can cause headaches or the eyes to feel tired. In young children it’s usually identified as a squint or “lazy eye.” The condition can also be caused by diabetes or a tumour (although these are very rare).
The diagram on the right, courtesy of Bupa, shows what happens to light that enters the eye of someone who is long sighted which causes the blurring of close objects.
How laser eye surgery can correct long-sightedness
Laser eye surgery cures long-sightedness (hyperopia) by altering the shape of the patient’s cornea (ie giving it more a curve). This alters the way light enters the eye so that the retina receives it differently.
The surgery itself, which involves removing tissue from the edge of the cornea, lasts no longer than 30 minutes and is painless thanks to the use of a local anaesthetic. There may be mild discomfort following the surgery and the patient may experience dry eyes for several days afterwards but this should improve as time goes on. One of the main benefits of laser eye surgery, as opposed to traditional surgical techniques, is the fact that because it’s carried out by laser rather than an instrument, the chance of infection is extremely low.
What forms of laser eye surgery can correct long-sightedness?
- Laser-assisted in situ keratomileusis (LASIK). This is the most common form of laser eye surgery here in the UK. It involves cutting a flap in the cornea and, once the laser has been used, allowing it to fall back down via natural suction.
- Photorefractive keratectomy (PRK). This form of eye surgery involves actually removing some of the cornea and modifying its shape using a laser. The surgeon identifies how much tissue to remove by means of a computer and the severity of the condition.
- Laser epithelial keratomileusis (LASEK). In this type of surgery the surgeon dabs alcohol onto the cornea to help remove tissue from it. The laser then alters the shape of the cornea to make it more curved. As with LASIK the cornea returns to its original position via natural suction.
I’m long-sighted – does that make me a candidate for surgery?
All candidates for laser eye surgery in the UK must be aged 21 or over. The reason for this is because up until the age of 21 an individual’s eyes are still developing and could change prescription quite radically. Anyone who has experienced a large alteration in their prescription within the two years preceding a consultation for eye surgery will also find themselves advised against the procedure. This is because a surgeon would prefer a patient’s eyes to settle before operating.
Candidates with diabetes may find themselves similarly turned away, as would pregnant or breast-feeding mothers. In the case of the latter hormones can interfere with focusing. Possible patients with cataracts, glaucoma or those with an immune condition may find themselves similarly rejected. In the case of the latter this would be on the basis that it could prove too difficult for the body to cope post-surgery.