Laser Eye Surgery
Is the world a complete blur for you without your glasses or
contact lenses? And when you do get your glasses on, do you
resent the lack of freedom in all your movements? Perhaps it's
time you went in for corrective eye surgery.
Most corrective eye surgery is technically known as refractive
eye surgery, an elective procedure intended to correct common
eye disorders, or refractive errors, such as myopia
(near-sightedness), hyperopia (far-sightedness) and astigmatism
(distorted vision).
Where does laser eye surgery come in?
Laser refractive surgery is rapidly becoming the most
technologically advanced and popular method available today to
correct refractive errors, primarily because it provides
near-total precision and predictability. However, there are
still a relatively small number of ophthalmologists in the US
who are trained in laser refractive surgery and in the
calibration and operation of the laser.
The excimer laser, which is used in this type of surgery,
received FDA approval in 1995 for correcting mild to moderate
nearsightedness. At present, the excimer laser is approved for
use in procedures called photorefractive keratectomy (PRK) and
laser in situ Keratomileusis (LASIK).
Photorefractive Keratectomy
Performed with local anesthetic eye drops, PRK is a refractive
surgery that reshapes the cornea by removing tiny amounts of
tissue from the outer surface with a computer-controlled
ultraviolet beam of light. The beam is so precise that it can
notch a strand of human hair without breaking it. The procedure
is the commonest form of laser eye surgery, takes only a few
minutes, and you can get back to normal life in a couple of days.
Is Laser Surgery for You?
Millions of patients have experienced total freedom from any
kind of eyewear after laser surgery, but there are cons too, as
with every surgical procedure. It is best to find out whether
you are eligible for laser eye surgery. Here's a checklist so
you don't end up with worse eyesight than you had before you
went in:
- People who are slow healers or have ongoing medical conditions
like glaucoma or diabetes are not good candidates for laser
surgery
- Those with uncontrolled vascular disease, autoimmune disease,
or people with certain eye diseases involving the cornea or
retina are also poor candidates, so make sure you have a long
chat with your doctor before you opt for surgery
- Pregnant women should avoid refractive surgery of any kind
because the refraction of the eye may change during pregnancy
Facts you should know
- You needn't worry if your pain threshold is low, since there
is hardly any discomfort during surgery. Once the anesthetic
wears off, the degree of pain varies from individual to
individual, but any irritation is minor and usually vanishes
within hours
- Worried about when you can return to work? Usually in one to
three days post-surgery, but a better idea is to wait until you
feel up to it
- Convalescence is minimal, and usually you can be driven home
about 30 minutes after surgery. Typically, your eyesight
improves within 3 to 5 days
- According to numerous surveys in the U.S. and worldwide, the
effects of surgery appear permanent. As people age, however,
their vision deteriorates naturally, so re-treatment may be
necessary
- Laser surgery does not really restrict your activities, except
you should not rub your eyes after surgery. Other than that, you
can do whatever work you feel up to provided you follow doctor's
orders
The risk factor
In one word, minimal, but there have been a handful of cases
where complications resulting from laser eye surgery have
resulted in corneal transplants. So here goes:
- There is about a 0.1 percent chance of the cornea becoming
infected after PRK, which usually means added discomfort and a
delay in healing, but no long-term effects within a period of
four years
- It is as yet not possible to definitely predict how your eye
will respond to laser surgery. As a result, you may still need
lenses after surgery for good vision. In some cases, a second
procedure can improve the initial result
- Some patients find that their best vision with corrective
lenses is worse than it was before the surgery. This is a result
of either irregular tissue removal or development of corneal haze
- However, corneal haze is part of the normal healing process
after PRK. In most cases, it has little or no effect on the
final vision. However, some cases of excessive haze interfere
with vision. As with under-correction, this can often be
corrected by additional laser treatment.
- In some patients the effect of surgery gradually fades over
several months. In such cases, a re-treatment is once again
usually sufficient
- Some patients experience the halo effect, an optical effect
noticed in dim light. As the pupil enlarges, a second faded
image is produced by the untreated peripheral cornea. This can
interfere with night driving. However, recorded cases are
extremely rare.
As of now, a number of other lasers for eye surgery are being
tested to determine their safety and efficacy. Such tests may
allow for clinical studies involving the excimer laser and the
correction of farsightedness, provided the FDA grants approval,
which is something a potential patient should always check.