those who would prefer to correct their eye aberrations
without glasses or contact lenses, LASIK is the
obvious choice. LASIK, the short for laser in situ
keratomileusis, is the most prevalent surgical
practice in correcting refractive errors of the
eye for those who can afford it.
Though a surgical and reversible procedure,
LASIK has gained immense popularity for its encouraging
outcome in its aim to provide better vision than
glasses and lenses, its adaptability and its
constant endeavor to ensure better quality unaided
vision. In 1995, it was approved by the Food
and Drug Administration in the US.
The eye conditions that lasik corrects
Some of the errors that LASIK can correct are
- myopia, hyperopia and astigmatism. The ranges
of up to which LASIK works for these errors,
however, varies according to clinical analysis
of predictability, effectiveness, safety, post-operative
stability and condition of eyesight.
LASIK also corrects refractive inaccuracies
in the following cases:
- After other refractive practices like PRK,
radial keratotomy, intracorneal ring.
penetrating keratoplasty, intraocular lens
implant after cataract removal.
- With other
refractive techniques for very large ametropias
- In pediatric cases
for certain refractive or strabismus
conditions which cannot be
corrected with contact lenses and glasses.
LASIK is also being developed further in its
ultimate aim to ensure better postoperative vision
than that provided by glasses and contact lenses.
A look into the past
The history of LASIK goes back to when Professor
Jose Ignacio Barraquer, developed myopic keratomileusis
in 1949 in Colombia. This process used a cryolathe
for corneal refractive modifications. The term
keratomileusis comes from the Greek word keras
meaning ‘horn-like’ and referring
to the cornea and smileusis meaning carving.
In 1964, Krwawicz developed the technique of
raising the corneal cap for removal of the central
tissue, which came to be known as keratomileusis
in situ. This was further developed by Pureskin
in 1967. Later Dr. Luis Antonio Ruiz, pioneered
a microkeratome (the apparatus for the procedure)
with gears. This made automated lamellar keratoplasty
(ALK) possible and hence led to its increased
popularity. Another milestone was achieved, when
laser technology was introduced as a part of
the ALK process.
The LASIK process
The LASIK process involves the lifting of the
anterior flap of the cornea with a keratome and
the application of an excimer laser to remove,
add or modify the stromal surface and hence achieve
refractive correction of a wide range of errors.
There are a few diagnostic points to remember
before the surgery:
- The minimum
age for LASIK is normally 18 years, other than
- Cases must be chosen for
LASIK on the basis of how successful the results
may be vis-a-vis
other refractive surgeries like radial keratotomy,
PRK, or laser subepithelial keratectomy (LASEK).
counseling and informed approval is vital.
check of the refractive stability of the
patient is essential before the operation
ensuring enduring effects.
- Potential cases
must be subjected to a comprehensive eye
screening (visual acuity,
videokeratography, wave front analysis,
examination, retinal evaluation, eye
dominance testing and tests for monovision
- LASIK is unsuitable for
cases with keratoconus or active corneal
pregnant or lactating women.
- For patients
using contact lenses, they should be discontinued
- All cases should be
evaluated for central corneal thickness to
confines of corneal
Operative preparation and procedure
of the patient in a sterile manner.
of the eye with topical anesthetic drops.
sedation 45 minutes before the surgery. The
patient should be just relaxed and
not over sedated, since the surgery requires
to ensure correct fixation.
surgical skin and eye preparation.
preparing the apparatus and the laser suite,
as both affect
- Keratectomy: A process
that readies the patient for the surgery
with marking of the
epithelium, determination of
the thickness of the incision,
placing of the LASIK pneumatic
suction ring etc.
- Laser ablation
is the core of the surgical process.
of the corneal flap is the closing step.
- Right after surgery the patient
is administered one drop
of antibiotic and non-steroidal
orbit guard is placed, without any pressure
Advantages and disadvantages of lasik
Benefits of LASIK
to correct a wide range of refractive errors
- Speedy recovery.
- Relatively painless
- Comparatively comfortable healing.
- Risk of serious
- Huge costs.
- Risks involved with lack of
- Problems associated
with effectiveness, predictability,
safety, and stability.
- Microkeratome-related complications,
and rare complications
like dry eye symptoms,
diffuse lamellar keratitis
etc. But none of these
pose a threat