LASIK or Laser-assisted in situ keratomileusis is laser eye surgery used to correct vision problems such as myopia, hyperopia, and astigmatism. It involves reshaping the cornea to correct refractive errors and vision problems.
Invention of spectacles was a great achievement at a time when patients with refractive error were severely handicapped or practically blind. Spectacles enjoyed a high degree of popularity for a long time, but now their disadvantages such as, cosmetic blemish, restricted field of clear vision, aberrations, obstruction in sports and physical discomfort, are apparent. However, this does not mean that spectacles are to be condemned. There are still many situations where spectacles are the only alternative available for restoration of vision and also a respectable visual device.
A question that always haunts the minds of the ophthalmologists and patients alike is “Why should we depend on prosthesis when it is possible to restore natural vision with all its inherent advantages (not just cosmetic)?” The answer to all our doubts and apprehensions lies in LASIK Surgery.
Wave-Front Optimized Or Custom LASIK
Wave-front guided or custom LASIK measures higher order aberrations present in the optical system of the eye and attempts to correct it. Moreover, the lasik treatment maps generated, maintain the natural (prolate) profile of the cornea, there by, preventing induction of any aberrations. All this translates into better contrast and night vision.
Intra LASIK (Femto Second LASIK)
Also called I LASIK or bladeless LASIK or all LASER LASIK or INTRALASE. It is a form of lasik where the corneal flap is raised using femtosecond LASER microkeratome rather than the mechanical microkeratome which uses blade. Thus the only difference is in the way the LASIK flap is created. It is misleading to think there is no cutting – therefore flap related risks are same in laser & blade. The flap thickness may be more predictable in the intralase group & thinner flap can be safer with femtosecond LASER. However the excimer LASER correction of the refractive error on stromal bed is same as in LASIK.
EPI-LASIK Or LASEK/PRK
In patients with thin corneas it may help to lift just a thin epithelial flap as in Epi – LASIK or remove epithelium using alcohol as in LASEK. This leaves behind greater amount of tissue in the corneal bed to achieve higher refractive correction. PRK along with use of Mitomycin – C has the same effect. Although it is possible to correct greater amount of refractive error in these procedures but the recovery is slow & more uncomfortable than in LASIK and there are greater chances of haze developing in the cornea especially with higher correction.
It is extremely important to determine who is a suitable candidate for eye surgery. The important criteria are:
- Refractive error: Myopia between -1 to -12 diopter or Hypermetropia up to 6 diopter
- Astigmatism of up to 6 diopters
- Minimum age 18 to 21 years
- Refraction should have been stable for last 1-2 years
- Presence of keratoconus, thin corneas, corneal inflammatory diseases, herpetic keratitis and autoimmune diseases makes a person unsuitable for LASIK
Preoperative Before the Preparation
- Refraction under cycloplegia
- Corneal topography
- Ultrasonic pachymetry (to measure thickness of cornea)
- Detailed retina examination
- Intraocular pressure examination
- Informed consent procedure
LASIK is performed under eye drops anaesthesia, so no injection is required. Wavelight Allegretto LASIK machine has a high speed (250 Hz) eye tracker device. This device constantly monitors the position of the eye and realigns the Laser to the exact position on the eye. The steps of lasik eye surgery are:
1. After the anaesthesia, the face of the patient is covered with a drape leaving only the eye exposed. An eyelid speculum is then applied to retract the eyelids and the patient has to look at a blinking green light.
2. A vacuum ring is placed around the cornea, which serves to stabilize the eyeball and also acts as a platform for the microkeratome. When vacuum is activated, the vision becomes hazy and pressure on the eye is felt.
3. The automated Moria Microkeratome dissects through the superficial layers of the cornea and the corneal flap is folded back. During this step the patient hears the sound of a motor in front of the eye.
4. Wavelight Allegretto high speed (200 Hz) Excimer Laser ablates the stromal bed to resurface it to a desired curvature. What makes the Excimer laser so well-suited for corneal ablation is its ability to remove tissue with accuracy of up to 0.25 micron with each pulse. Often, only 50 microns of tissue are removed to achieve the proper amount of correction.
The Exeirner produces a non-thermal light beam that eliminates the possibility of thermal damage to surrounding tissues. This Laser deploys 0.95 mm flying spot with truncated gaussian profile Laser beam to achieve correction of refractive errors, higher order aberrations and fashioning of smooth transition zones. During this step a clicking sound is heard and an odour of ablating tissue (similar to charring hair) is smelt and a flickering light is seen close to the eye. All this while patient needs to concentrate on the entre of the blinking red spot of light.
5. The corneal flap is then repositioned and allowed to dry for a few minutes. The flap self-seals without the need of sutures.
6. Antibiotic and other eye drops are prescribed. The patient is instructed to report back the next day.
- Avoid swimming and splashing of water on the eyes for a month
- Avoid rubbing the eyes for a month
- Use sunglasses to avoid bright sun, dust, wind and air pollution
- Avoid excessive viewing of TV or work on computers for a week
- Use medicines regularly as advised
- Consult your eye surgeon in case of any problem
No surgical procedure is without any complication, however LASIK is relatively a very safe technique for correction of refractive errors .There is a rare possibility of complications like glare, minor over & under correction, decreased contrast sensitivity, epithelial in growth etc.
Flap related complications on the table are also a rare possibility and most of them can be managed on the table; however, only some need the surgeon to postpone the LASIK surgery to a later date for better management.
- Under or over correction
- Button holing of flap
- Reduced contrast sensitivity
- Corneal perforation
- Central island
- Decentration of ablation
- Corneal infiltration
- Flap damage
- Corneal ulceration
A typical schedule for LASIK patient is as follows:
- Day 1 - Detailed eye examination
- Day 2 - LASIK Surgery (2-4 hours spent in the centre)
- Day 3 - Review visit for postoperative examination
- Day 7 - Review examination
Patient may travel between days 3 and 7.
- State-of-the-art infrastructure with advanced LASER
- Specially designed operation theatre for maximum sterility
- Comprehensive pre-LASIK screening to assess the fitness criterion of the candidate before the surgery.
- Use of advanced corneal topographic system and accurate ultrasonic corneal thickness measuring instruments for accuracy.
- Single use disposable consumables for high precision, accuracy, sterility and safety of the each patient.
- Highly skilled and experienced surgeons, supported by qualified staff
- Surgery for Glaucoma & Retina Laser
- Lasik: Bladeless Laser
- Diabetic Eye Care
- Paediatric Eye care
- Squint Correction
- Corneal Transplant Surgery
- Eyelid Cosmetic Surgery
- Cataract & Lens implant Surgery: MICS& Laser
How Soon Can I Resume My Normal Activities?
The recovery is very fast owing to the simplicity of the procedure. One can resume the normal activities as early as after 24-48 hrs of the surgery with only a few precautions.
Will My Power Come Back After the Surgery?
No, the power never comes back. Only in very cases where the refractive power is very high to begin with, a minimal residual power may remain which can be corrected by what is known as enhancements, (which again can be assessed only after 1-2 months of the operation) depending on the patients need.
Can I Go Blind?
No, there has been no reported case of blindness so far.
Can there Be Any Complications?
The chances of complications happening are rare but in the event of any such complication occurring, our surgeons are very competent to take care of them.
Which Is the Right Age to Get Lasik Done?
stable power of glasses for the last 1-2 years.
Is the Laser Treatment for Eyes Life Long
Yes, the LASIK treatment is designed to last a lifetime. Only after the age of 40 years, does a person require reading glasses.
Other Conditions & Treatments
- Diabetic Retinopathy
- Phakic Implantable Collamer Lens (IOLs)
- Squint (Strabismus)
Get Second Opinion
Get free second opinion from India’s leading specialists.