Global Health Asia-Pacific September 2020 September 2020 | Page 12

You Ask, They Answer
Q
: Who’s a good candidate for LASIK vision
corrective surgery?
A
: LASIK is suitable for people who are generally younger,
i.e., at least 18 and ideally not over 45.
When you’re older than 45, you’ll have presbyopia, a
condition where the lens cannot focus on close-up items,
such as in reading. LASIK is only good for correcting shortsightedness
(trouble seeing far away) and astigmatism (eye
can’t focus light evenly), but not presbyopia.
In other words, if you’re older than 45, you might still
need reading glasses after a laser correction. LASIK is also
not encouraged in people who are approaching an age when
cataracts might appear, i.e., in their sixties and onwards.
If you develop cataracts after LASIK surgery, your distance
vision will become blurry again. Moreover, after you’ve had a
cataract removed, any refractive problems can be eliminated
with a lens implant. Therefore, the best age to have LASIK is
when you’re younger. Generally, the lower age limit for LASIK
is 18 and above, as patients younger than that may not have
developed a stable refractive error.
Before anyone contemplates having LASIK performed, they
need to undergo a thorough eye evaluation to gauge their
suitability for the procedure. Persons who wear contact lenses
should lay off them for about a week before going for this
assessment.
Q
: What kind of problems can be treated with
LASIK?
A
: The best refractive error to be corrected by LASIK is in
somebody who has -0.75 to about -10 dioptre of myopia. If
the myopia is too mild, then laser refractive surgery’s cost or
risk benefit ratio is probably not worth your while.
There’s also an upper limit for laser correction. With
higher corrections, the cornea may become too thin after the
correction for a safe outcome. Thus, in people with extreme
myopia, an implantable collamer lens is the alternative to LASIK.
Q
: What does the procedure involve and how long
does it take for patients to recover?
A
: LASIK uses a laser beam to alter the shape of the cornea.
By altering its shape in somebody with refractive error,
the eye can focus an image sharply on the retinal plane again.
A laser is used because of the precise nature of the
correction. On average, 95 percent of people who have had
laser vision correction are able to achieve the intended target
of not being dependent on glasses after the surgery. The effect
is permanent.
LASIK is done as an outpatient procedure and usually
takes about five to 10 minutes per eye. Most patients have the
procedure performed sequentially on each eye on the same day.
After the procedure, the patient is advised to go home
and rest as the vision is still foggy in the first six hours after
the procedure. Generally, the vision will be sharp by the
following day.
Q
: In some cases, LASIK doesn’t completely fix
refractive errors and people still require glasses or
contact lenses. Why is this the case? What’s the success
rate of the procedure?
A
: Although most people do not need glasses after the
procedure, about five percent of them may develop a
phenomenon called regression. This is when the healing of
the cornea results in the development of a mild degree of
short-sightedness. If it’s a mild myopia that develops from the
regression, this is not bothersome and most patient are still
satisfied. However, some patients with regression will still
have significant myopia that necessitates an enhancement
procedure. As a rule, the enhancement procedures are
infrequent, and they usually take place three months after the
initial procedure.
Q
: Are there side effects from LASIK?
A
: The most common side effect of LASIK is dry eyes.
The vast majority of people who experience dry eyes
have minor symptoms and revert back to normal after a few
weeks. Dryness of the eyes can be usually treated with artificial
tears eyedrops.
Another common side effect is the appearance of glare and
haloes during night vision. Patients may notice “rings of lights”
next to a light source or a “starburst effect” from the headlamp
of an oncoming car. These night vision disturbances similarly
will disappear after a few weeks.
Dr Wong Jun Shyan
Dr Wong Jun Shyan is a consultant
ophthalmologist and CEO of International
Specialist Eye Centre in Kuala Lumpur.
10 SEPTEMBER-OCTOBER 2020 GlobalHealthAsiaPacific.com