What is LASIK Surgery?

LASIK (or Laser-Assisted In-Situ Keratomileusis) is a surgical procedure for correcting vision problems like myopia, hyperopia, and astigmatism. This is an advanced laser vision correction technique in which the curvature of the cornea is reshaped using a laser that is capable of removing tissues with precision. Patients with stable (unchanged) refraction (spectacles power) for at least a year and should be at least 18 years of age are best suited for this procedure.

LASIK is preferred by those who find spectacles visually unacceptable, those who are intolerant to lenses, those who would like to participate in outdoor sports or opt for professions demanding excellent uncorrected vision.

However, though doctors strive to make the refractive error zero after LASIK, this may not always be possible. The main purpose of surgery is to reduce the dependency upon glasses for the patient as much as possible. Some of the possible side effects of LASIK are under correction, overcorrection, glare, halos, and reduced contrast sensitivity. Therefore patients must have a detailed eye examination before surgery, followed by a realistic discussion with the surgeon on the expected outcome of surgery.

What are the refractive errors that can be corrected by LASIK?

Myopia or short-sightedness occurs when light rays are focused in front of the retina causing blurred vision, particularly when viewing distant objects. Objects that are near may be seen clearly, but not those that are far away. Myopia is often hereditary, usually due to an abnormally large eyeball or steeply curved cornea. Because the eyeball grows with age, myopia tends to progress, usually stabilizing by the time the person is 20 years old.

Hyperopia or far-sightedness is the opposite condition of myopia, where the light rays converge at a point beyond the retina. Initially objects that are near seem blurred, though distance vision remains clear. However, with age, objects at all distances become blurred.

Astigmatism is an irregularity in the shape of the normally spherical cornea. The cornea is shaped like an egg or the back of a spoon, causing distortion of both distant and near vision.

Who would prefer LASIK surgery for their eyes?

Those who do not want to wear spectacles or contact lenses.
Those who feel visually and socially restricted by spectacles or contact lenses.
Those who are intolerant to contact lenses.
Those who want to participate in certain outdoor sports where using spectacles or contact lenses may be a problem.
Those who plan to join certain professions wherein excellent uncorrected visual acuity is a prerequisite.

Who can undergo LASIK
procedure?

Those patients whose spectacle prescription does not have a significant change for the past 12 months.
Those who do not have any ocular surface abnormality such as dry eyes.
Those patients whose cornea is adequately thick and whose corneal curvature is suitable to be operated upon.

What tests are performed before LASIK?

At Anjani Eye Hospital, a patient willing to undergo LASIK / Refractive Surgery undergoes a thorough eye examination including refraction, general eye examination with slit lamp and dilated retinal examination. After these basic tests, the patient undergoes evaluation of corneal thickness, corneal curvature, optical aberrations etc. using state-of-the-art diagnostic equipment. These reports are studied by the LASIK surgeon before making a final decision, in consultation with the patient.

What to expect during LASIK Surgery?

At Anjani Eye Hospital, LASIK procedure is done on an out-patient basis, meaning you go home immediately after surgery. It is advisable, that a relative or friend, who can take you home after the surgery, should accompany you. The procedure is performed under topical anesthesia.

You will be made to lie down on a couch and asked to look up at the microscope where you will see a blinking green light. When the suction ring is applied, your vision will fade out. You will start seeing the light again after the suction ring is removed. The whole procedure will be over in a few minutes. Usually, there is no pain during the procedure.

What to expect after surgery?

Once surgery is over your eye will be covered with a pair of protective glasses after the administration of some drops and ointment. You can return home immediately. You may experience pain for the first 24 to 36 hours, for which you will have to take oral analgesics. You will have to come for follow up visits from the very next day onwards. The routine follow up schedule is as follows:

First check-up in the morning after surgery
Seven days from the date of first check-up
Six weeks from the date of surgery
Three months from the date of surgery
One year from the date of surgery

You will undergo tests at each visit to the hospital aimed at assessing your visual acuity. It is important that you visit the doctor as scheduled on every appointment. You will be advised to use eye drops or other medication during the post-operative period.

When will you know the result of the procedure?

Your vision will become clear over a few days, with majority patients not requiring glasses at the end of first week itself.

Remember, LASIK decreases the dependence on glasses for day to day work. Although LASIK is an excellent procedure for low and moderate refractive errors, it may not totally remove the need for using glasses in everybody. Sometimes you may require another round of treatment with laser, particularly with higher degrees of refractive error.

What are the possible side-effects of LASIK?

LASIK surgery is very safe and effective. But in some patients there could be side effects. Your doctor will be happy to discuss these with you and clear your doubts before surgery.

Undercorrection / overcorrection: Undercorrection may sometimes be planned intentionally or may occur as an unintentional effect. As a result, you may need to wear glass prescription (although not to the extent that you were wearing earlier), even after the surgery. If the degree of residual refractive error is significant, the eye may be re-treated at a later date. Overcorrection can occur very rarely.

Glare / halo effect: You may feel some sensitivity to light at night or in bright sunlight. Sometimes in dim light, you may see a faded ghost image around the sharp bright image. This usually passes away after the first few days or weeks.

Decrease in contrast sensitivity: Some people find that their night time vision has become a bit dull. This happens because of a decrease in their ability to discriminate between different contrast levels.

Flap complications: Sometimes the anterior corneal flap that is made in LASIK may not be complete if the keratome stops mid-way because of suction loss. In this situation the flap is repositioned and ablation is deferred. The surgery is re-attempted after three months. In rare instances, the flap may tear or become detached, which may require suturing.

Corneal ecstasia: Can occur if the corneal thickness is less to begin with, or if the cornea is thinned more than it can withstand with the lasers. Therefore, persons having inadequate corneal thickness are not suitable candidates for LASIK.

Other complications: Serious complications like corneal infections, corneal edema, corneal perforation etc., though possible, are extremely rare.

AM I FIT FOR LASIK?

Some clinics turn away up to 20% of people as they believe that they are not suitable for laser eye surgery. But that doesn’t always mean those people can’t be helped. We can treat 98% of those who come to us.

Why are so many more patients suitable for laser eye surgery at our clinic?

Our Laser eye Surgeons are among the very best in the world.
We believe in helping all patients, not just the quick and easy cases.
We take the time to deeply analyze each patient’s eyes and have the expertize to customize treatments for each eye.
Many clinics aim to ensure consistent results, and a quick turnaround, by focusing on the least complicated cases. Many simply do not have the experience or expertise to tackle more complex or unusual conditions. Our Clinic is different on both counts.

Candidates before going under a Lasik treatment must fulfill the following criteria:

Age: A patient must be above 18 years of age and preferably less than 40 years of age before he or she take appointment for having a Lasik surgery. Stability in vision: Patient’s glasses power must be stable almost for one year prior to this surgery.

Dry Eye: Patient’s must not be having dry eyes. For this Schirmer’s test is done. And if you are found to have dry eyes better get that treated first before planning Lasik Laser procedure.

General Health: Patient should not have any other systemic problem like diabetes or collagen disease or be under any other medical treatment.

Lasik is not for a pregnant/ Lactating patient: An Ophthalmologist should avoid Lasik surgery of those patients who are under the course of pregnancy or is lactating (Breast feeding her child). This is because; there may be some effects on hormones.

What are the alternatives to LASIK Surgery?

For patients where the corneal thickness is not sufficient for doctors to perform LASIK, there are other alternatives. (Generally we do not do LASIK if the thickness is less than 470μm for spherical errors and less than 490μm for cylindrical errors). In such cases the options are:

1. Photorefractive Keratectomy (PRK)

This was the most popular laser procedure for correcting refractive errors before the advent of LASIK. Here the laser is applied to the corneal surface. Since the epithelium (surface layer of the cornea) is removed, this leads to greater activation of inflammatory mediators and better healing. The problems of excessive healing or haze (scar) can decrease the clarity of vision, and regression or refractive error returning due to the addition of tissue. Haze and regressions are more if the error is high. Generally PRK is recommended for cases up to 6.0 diopters.

The problems encountered in the early post-operative period with PRK are more painful (because of epithelial defects), and delay visual rehabilitation as it takes 3-4 days for the epithelium to heal.

Early visual recovery, more comfort, practically no haze and very little regression (not in all cases) are the advantage of LASIK over PRK. PRK is preferred in cases with borderline corneal thickness where LASIK might be risky. Excessive ultraviolet exposure is a risk factor as it might cause haze after PRK; this is a problem faced predominantly by Indian subjects. After surgery, to minimize haze surgeons use ointments. Anjani Eye Hospital is one of the few places in India that offers this procedure, and the results have been very encouraging.

2. Phakic Intraocular Lens

The Phakic IOL technique is recommended for patients with moderate to severe myopia, i.e., very high refractive powers (near-sightedness). It is used safely and effectively for the acutely near-sighted who are tired of wearing thick glasses and are not suited for the customized LASIK procedure, because they have low corneal thickness or flat corneas.

In this procedure an intraocular lens, (made of biocompatible material that has been tested and proven fit for implantation for over 50 years), is fixed in front of the natural clear lens — behind the iris. The word ‘phakic ’means that the natural crystalline lens is left in the eye. This is important because the natural lens plays an important role in helping the eye adjust between seeing objects that are near and far. This gives the eye another focusing lens that provides high-quality, high-definition vision like a normal eye. Three types of lenses are used for this purpose: anterior chamber, iris fixated, and posterior chamber (used most commonly).

Phakic IOL is performed as an outpatient procedure that takes 15 – 30 minutes. Usually one eye is treated at a time. The doctor uses an instrument to comfortably hold the eyelids open during the procedure. A local anesthetic is given to the eye, so the procedure is virtually painless. A small incision is made in the cornea and the phakic IOL is centered in front of the natural lens in the pupillary area behind the iris. The incision routinely seals on its own, however, in some eyes it is closed with microscopic stitches that dissolve on their own.

The quality of vision is usually very good in patients after phakic IOL as compared to those with LASIK. The patient cannot feel the implanted lens.

Phakic IOL does not change the natural appearance of the face and does not require any special care or maintenance. Although it is intended to be permanent, the procedure is reversible if desired. The implanted lens can be removed any time, as the surgery does not affect the important natural structures of the eye.

3. Clear Lens Extraction (Refractive Lens Exchange) with Negative Intraocular Lens Implantation

This option is not considered for individuals with myopia as literature has suggested increased incidence of retinal detachment after removal of the lens. Though the incidence of retinal detachment is less in the case of hyperopia, this procedure is not recommended in young people with hyperopia since they stand the risk of posterior capsular opacification. Refractive lens exchange with multifocal or monofocal intraocular lens is recommended for high hyperopes over +5 D after the eye of 40 years.

Laser Sight Correction Treatment

Assessment for LASIK, LASEK, and Other Refractive Surgery Procedures at Our Eye Practice Whether you are shortsighted, long-sighted or just astigmatic, we can advise. Hence, from the above it is quite clear that if one wants to have Lasik surgery, then at first one must have a proper consultation with a doctor. Then, after having confirmation from doctors, patients should decide on where they will get the best treatment.

Assessment for Laser Eye Treatment / Tests Done Before Planning LASIK

Proper assessment is absolutely essential prior to treatment. Not all Lasik treatment centres have time to go through the Individual’s vision requirements in relation to their life style and expectations. We have been doing laser surgery since years and we offer a wide range of ophthalmic medical services.

LASIK EYE SURGERY- PREOPERATIVE EXAMINATION

Your LASIK doctor will perform a dilated eye exam to ensure your eyes are healthy for LASIK eye surgery. The surgeon will evaluate the shape and thickness of your
cornea, refractive errors, pupil size and general overall health to determine if you are a candidate for LASIK. The chance of developing dry eyes will also be evaluated, and a treatment plan may be recommended to reduce your risk of developing dry eyes after LASIK surgery. If you are having a Custom LASIK you likely will have a 3D imaging of your eye, referred to as Wavefront analysis, which creates a more precise map of overall aberrations affecting your vision. Because Contact lenses alter the natural shape of your eye, you will be asked to stop wearing contacts for a specified period of tie prior to your surgery date. Typically the time to remove soft contact lenses is 3 days to 1 eek and for Hard or RGP lenses is 3-4 weeks.’

Tests performed before LASIK are:

Glass power testing

Corneal thickness (Pachymetry)

Corneal Topography/ Aberrometry

Intraocular Pressure (IOP testing)

Schirmers Test (Dry Eye Testing)

Retina check up (Dilated check up)

Before going under a Lasik surgery, Checking of these is important as corneal thickness has an important role in this Lasik Surgery. As an International standard, a 250-μm residual stromal bed (RSB) is fairly accepted as the minimum tissue that must remain after Lasik Surgery; however, some surgeons have more conservative approach – prefers to keep 300-μm residual stromal bed (RSB). Hence, it is the responsibility of eye specialists to verify these problems thoroughly and then suggest the patients for having a Lasik eye surgery. Any patient may have any type of eye injury. Every eye specialist should take this matter for further verification. Patients are having dry eyes problems then they must not go for a Lasik treatment

The original optical properties of the cornea need to be taken into account in advising on a corrective treatment, otherwise visual quality may be degraded causing sideeffects like glare and poor night vision. Some treatments change the shape of the cornea in an arbitrary way that is unsympathetic to the original optics, the way our eyes work. Dr. Shweta Mokadam will advise you, taking into account your expectations, your life style, your occupation and the main purpose that you want eye correction for. We use maps of the eyes optics (wave-front) or maps of the shape of the surface of the eye (topographic) at our eye practice to take into consideration any distortion of the surface of the eye, for example by injury or other surgery. Contact at our clinic, to learn more about receiving advice on which is the most appropriate treatment for you.

LASIK (LASER ASSISTED IN-SITU KERATOMILEUSIS)

LASIK is the mainstay of modern laser refractive surgery. When performing LASIK a thin flap of corneal tissue is made with a special laser called a ‘femtosecond’ laser (ILASIK) or with a surgical instrument called a microkeratome (Standard & Customised LASIK). The underlying corneal tissue is then reshaped with a laser beam and the corneal flap is replaced. The surface skin of the eye is not disturbed in LASIK eye surgery because it is attached to the flap.

‘All-laser LASIK’, where the flap is made with a femtosecond laser, is preferred for many treatments for reasons of safety and accuracy. However, some treatments call for the use of a microkeratome.

The advantages of LASIK eye surgery are that minimal, if any, discomfort follows the procedure. The visual recovery is very fast, with most people meeting the driving standard in about twenty-four hours. Final visual stability is usually reached within a few days, although there may be a very small change over a couple of months or so. Up to approximately 8 dioptres of myopia with or without astigmatism and about 3 dioptres of hyperopia with or without astigmatism may be treatable, depending on the individual.

WHAT IF I AM UNFIT FOR LASIK SURGERY NEW TREATMENTS

Latest advances allow tissue to be removed from within the cornea with barely any disturbance to the surface at all. This can have advantages in retaining corneal strength and allowing higher amounts of correction.

Whichever method is appropriate for your eyes, we will advise what is the safest and most dependable way. To learn more about treatments, contact our clinic.

PRK (PHOTOREFRACTIVE KERATECTOMY) AND LASEK (LASER ASSISTED SUB-EPITHELIAL KERATOMILEUSIS)

For patients who are unsuitable for LASIK surgery, PRK, LASEK and epi-LASIK can be done. All are surface treatments that differ from one another only in detail. All involve sculpting the corneal material that is directly beneath the surface skin of the eye. Surface refractive surgery procedures can be used with confidence for correcting myopia up to four dioptres, astigmatism up to three dioptres, and hyperopia up to two dioptres. It is possible to treat more dioptres, but generally less reliably than with LASIK. Visual recovery is slower than with LASIK so it is usually sensible to treat one eye at a time.

PHAKIC IOLs/ ICL KERATOCONUS

If you are not fit for LASIK, you may be suffering from Keratoconus.

CLEAR LENS EXTRACTION (CLE)/ REFRACTIVE LENS EXCHANGE (RLE)/ Presbyopic Lens Exchange (PRELEX)

The procedure done in Clear Lens Extraction (CLE) is similar to cataract surgery, wherein natural crystalline lens is replaced with an artificial lens correcting the vision problem of patient. Most of the times, the artificial lens corrects vision for distance only if mono focal lens is chosen. In that case, usually person needs a pair of reading glasses for near work, if monofocal lens is placed and does not need any glasses both for distance and near if Multifocal lens is placed. There are variety of lenses available which correct both near & distance & astigmatism related refractive error of eye. The selection of lens is purely based on patient lifestyle & recommendation by treating surgeon. Clear Lens Extraction (CLE) procedure can be done for patients who do not have cataract but unfit for Lasik Surgery for vision correction. These patients can have farsightedness or nearsightedness combined with astigmatism.

Refractive Lens Exchange (RLE): A lens transplant for older patients with refractive errors who are not candidates for laser vision correction.

Presbyopic Lens Exchange (PRELEX): A multifocal lens implant replaces the current lens of the eye to help patients over 40 with their near vision

LASIK