LASIK and Refractive Surgeries

Vision Correction Surgery with LASIK and Wavefront

Lasers have proved especially useful in eye care, where they are also used to correct refractive errors, thus minimizing or eliminating the need for glasses or contact lenses. We at Mansarovar Eye Hospital, Lucknow have an established reputation for performing laser refractive surgery or Laser-Assisted In-Situ Keratomileusis (LASIK) with extremely successful outcomes. It is a total refractive solution to get rid of glasses.

We also offer Wavefront assisted vision correction technology, which scores over other procedures for vision correction in several ways. This procedure not only helps correct common vision defects such as myopia, hyperopia, and astigmatism (cylindrical vision), it is also capable of measuring and correcting even minute aberrations in the eye, giving results that were, until now, considered impossible.

What are Refractive Errors

The eye functions like a camera. Light rays entering the eye are focused by the cornea and the lens of the eye onto the light sensitive retina at the back of the eye, which is like the film of a camera. The retina then transmits a clear image, or photo, to the brain. In people with refractive errors like myopia (nearsightedness) and hyperopia (farsightedness), the light rays are not focused properly and blurred images are formed. These can be measured as aberration patterns.

In addition to spectacles and contact lenses for vision correction, LASIK surgery is now a widely accepted procedure. This is an advanced laser vision correction technique for correcting myopia, hyperopia, and astigmatism. In LASIK the curvature of the cornea is reshaped using a laser that removes tissues with precision of up to a thousandth of a millimeter!

Wavefront assisted customized LASIK is a cutting edge laser vision correction technique where a spot laser also removes

Plano and Wavefront Assisted Customised LASIK Surgery

Wavefront assisted customized LASIK is a cutting edge laser vision correction technique where a spot laser also removes tiny aberrations in the eye, that may occur after conventional (or Plano) LASIK, thus improving the outcome of the surgery.

Surgeons use an instrument called the aberrometer to measure minute imperfections in the eye, which are then corrected during surgery. While older lasers only correct the spherical and cylindrical power, the aberrometer can measure many more types of aberrations and correct them.

The procedure also minimizes the occurrence of new aberrations, which lead to night vision problems like haloes, glare and ghost images. This leads to more accurate vision correction and better night vision, along with reduced glare and enhanced contrast sensitivity.

In general, LASIK is recommended for patients with mild to moderate degree of myopia. More caution needs to be exercised while operating on patients with hyperopia. It is relatively easier to flatten the cornea (in myopia), but it is more difficult to steepen the cornea (in hyperopia). Making the cornea too steep may lead to a gradual regression of the power and a risk of the patient losing the best corrected vision. If the refractive error is high, in young patients contact lenses are preferable to surgery. For patients above the age of 40, LASIK will do away with distance glasses, but reading glasses will still be needed.

Who is Suitable for LASIK

Persons who opt for LASIK are those who find spectacles visually unacceptable, those who are intolerant to lenses, those who would like to participate in outdoor sports or people interested in professions demanding excellent uncorrected vision. Prospective patients should be above 18 years of age and their spectacles’ power should have been unchanged for at least a year. Further, they should not have any ocular surface abnormality such as dry eyes. Most importantly, the cornea should have adequate thickness for it to be operated upon.

Before the Laser Procedure

The patient undergoes a complete eye examination, in which the structure and functioning of the eyes are checked. An ‘OPD Scan’ is done to ascertain the thickness and curvature of the cornea. This also helps in ruling out keratoconus, a progressive thinning disorder of the cornea, which is a contraindication for LASIK. The ophthalmologist studies the test reports before making a final decision, in consultation with the patient

During Surgery

At Mansarovar laser surgery is done on an out-patient basis; this means you go home immediately after surgery.

Usually both eyes is treated at a time. The procedure is performed under topical (eye drops) 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 red 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. There is usually no pain.

After Laser Surgery

After surgery you will be given a pair of goggles and you can return home. You may have some pain for the first 24 to 36 hours, for which you will be prescribed oral analgesics. You will have to come for a follow-up visit the next day. Please be careful and follow the schedule suggested by the doctor

The suggested check-up schedule is:

First check-up on the morning after surgery
Seven days after surgery
One month after surgery
Three months after surgery
One year after surgery

When Will You Know the Result

You will undergo special diagnostic tests on each visit to assess your visual acuity. Your vision will become clear within a few hours to a few days. Rarely, another session of laser treatment may be needed, especially if you have a high power. This is done after three months.

Possible Side Effects

laser surgery is very safe and effective. But some patients may have side effects. Your doctor will discuss these with you and clear your doubts before surgery. Some possible side effects are:

Undercorrection/overcorrection: Undercorrection may sometimes be planned intentionally or may occur as an unintentional effect. As a result, the eye may remain short-sighted. If the degree of residual myopia is significant, you may be treated again later. Overcorrection occurs 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 will pass after the first few days or weeks.

Decrease in contrast sensitivity: Some people find that their night vision has become a bit dull. This happens because of a decrease in their ability to discriminate between different contrast levels. The Wavefront assisted procedure [ C-LASIK] minimizes night vision problems since minute imperfections and aberrations are also taken care of.

Flap complications: Rarely the anterior corneal flap that is made in LASIK may not be complete. In such situations the flap is repositioned and surgery may be reattempted after three months. In very rare instances, the flap may tear or become detached.

Corneal ectasia: This can occur if the corneal thickness is less to begin with, or if the cornea is thinned more than it can withstand. Persons with low corneal thickness are not suitable for LASIK. And another procedure called LASEK or surface ablation is advised. If this applies to you then you will be told at the time of initial assessment.

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

Important!

Although LASIK is an excellent procedure for low and moderate refractive errors, it may not totally dispense with the need. for glasses in everybody. Though doctors strive to make the refractive error zero, this is not always possible. The main purpose of surgery is to offer sufficient good vision so that patients are not dependent upon glasses most of the time. A detailed eye examination, followed by a realistic discussion with the surgeon on the expected outcome of surgery, will help you to know what to expect.

Alternatives to LASIK

Patients who are unsuitable for LASIK can opt for alternatives such as photorefractive keratectomy (PRK), phakic intraocular lens implant, and clear lens extraction (refractive lens exchange) with negative intraocular lens implantation.

Phakic IOL (Commonly known as ICL surgery) is recommended for patients with very high refractive powers, or those with very low corneal thickness or flat corneas who are unsuitable for LASIK. 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. Three types of lenses are used: anterior chamber, iris fixated, and posterior chamber. The quality of vision is usually very good in patients after phakic IOLs, as compared to those with LASIK.

In phakic IOL the lens is implanted inside the eye and cannot be felt. Unlike other implant procedures or lasers, this implanted lens can be removed any time, as the surgery does not affect the important natural structures of the eye. Therefore, the entire procedure is reversible.