What is Laser Vision Correction?

Millions of Americans, those who are severely nearsighted, far-sighted, or who have marked astigmatism, begin each day the same way – by groping for eye glasses or fumbling with contact lenses. If you are one of those who face this daily ritual and have dreamed of freedom, there is now a practical alternative for vision correction. Thanks to a miraculous medical advance, freedom from total dependence on glasses and contact lenses is now possible. A truly remarkable medical breakthrough, called laser vision correction, makes it possible to start each new day in a different way – by simply opening your eyes and enjoying your vision.

Laser vision correction improves refractive vision disorders. The term “refractive” refers to the way that light rays are focused in the eye. The major cause of refractive vision disorders (nearsightedness, far-sightedness and astigmatism) is a corneal curvature that is too steep or too flat for the length of the eye.

Laser vision correction includes a variety of procedures, designed to reshape the curvature of the cornea and improve the focus of the eye.

What does LASIK Eye Surgery Fix?


Nearsightedness, “myopia”, is a condition in which light rays entering the eye are focused in front of the retina. This common refractive disorder is usually caused by a corneal shape or curve that is too steep for the length of the eye.

Nearsighted individuals can see objects which are very close to them but have difficulty seeing objects which are further away. In this condition the laser is used to improve the focus of the eye by reducing the steepness of the cornea.

Chart Showing How Myopia Affects an Eye


Far-sightedness, “hyperopia”, is a condition in which light rays entering the eye are focused behind the retina. This disorder is caused by a corneal curvature that is too flat for the length of the eye.

Far-sighted individuals often have blurry vision both near and distance. In this condition, the laser is used to improve the focus of the eye by increasing the steepness of the cornea.

How Hyperopia Affects an Eye


Astigmatism is a condition in which light rays entering the eye are focused on two different levels either in front of or behind the retina. This disorder is caused by an irregular corneal curvature that may be too flat and too steep for the length of the eye.

Astigmatic individuals often have blurry vision both near and distance. In this condition the laser is used to improve the focus of the eye by remolding the flat and the steep portion of the cornea.

How Astigmatism Affects an Eye

The Excimer laser is a precise computer directed device which emits a cool beam of laser energy. The laser energy is designed to remove microscopic layers of corneal tissue in very tiny controlled increments. Each laser pulse reshapes the corneal surface by approximately 15 microns (a human hair is around 125 microns in width). The patient’s refractive error is programmed into the laser computer system before the procedure. This information directs the laser to either flatten or steepen the corneal surface as necessary to achieve the best possible visual result. Please see “wavefront” link for more information regarding wavefront guided excimer laser treatment.

Excimer Laser

There are basically two different techniques which are used by eye surgeons performing laser vision correction, LASIK (short for “laser assisted in situ keratomileusis”) and PRK (short for “photorefractive keratectomy”). For both these procedures, the laser is utilized in exactly the same way. The differences in the two procedures have to do with the way the cells of the surface of the cornea are managed by the surgeon, the rapidity of visual improvement, and the level of post operative comfort.

With PRK the surface of the cells of the cornea are removed mechanically, and the corneal tissue just beneath the surface cells is treated with the same excimer laser. Although the PRK procedure itself does not hurt, patients can experience some postoperative discomfort and visual recovery is less rapid than with LASIK. PRK is an effective procedure, but it is generally utilized by Dr. Kandavel to treat patients who are not candidates for LASIK, such as individuals with thinner corneas.

With LASIK the surgeon can use an ultra fast laser (Intralase laser) or a microkeratome to create a thin layer of the top portion of the cornea. The second laser treatment is performed beneath this thin corneal layer. The cornea layer is then gently repositioned over the surface of the cornea. The extraordinary natural bonding qualities of the cornea allow the effective healing to occur without using stitches. Dr. Kandavel only performs “all laser LASIK” there are no microkeratome blades involved whatsoever. Please see the “all laser LASIK” link for more information.

While the LASIK procedure is more complex than PRK, and requires a higher level of skill by the surgeon, it is generally associated with very little, if any, postoperative discomfort and visual recovery begins almost immediately. Because of the increased level of comfort and the almost spontaneous visual improvement experienced by most patients, “all laser LASIK” is Dr. Kandavel’s preferred technique for patients who are appropriate candidates for the procedure.

Technology is now so advanced that most refractive errors can be improved with laser surgery. There are some people, however, who should not consider laser vision correction. People who are very happy with their glasses and/or contacts should not have surgery, simply because they have no need for it. People under 18 years of age, and people whose refractive error is changing should defer surgery until the vision is stable. People who believe that they will be happy only with perfect vision without glasses or contacts should not have surgery. A realistic goal of the laser procedure is to reduce dependence on corrective lenses. While a perfect correction may be possible, it can not be guaranteed.

After 45 years of age the eye looses its ability to change focus and allow for both distance and near vision called Presbyopia. Monovision Laser Vision Correction can be an excellent technique to preserve both distance and near vision in patients who would otherwise have to wear bifocal glasses. The procedure is performed in the same way, but one eye is targeted for near vision and one eye for distance vision. For most patients with presbyopia, monovision laser vision correction allows for a fuller range of vision therefore reducing the patient’s dependence on glasses for both reading and distance vision. Dr. Kandavel will perform a complete evaluation to determine if you are a candidate for monovision treatment.

Dr. Kandavel performs laser vision correction at the state-of the-art Laser Vision Institute of the Valley in Encino, California. Patients are instructed to bring a friend or family member to drive from home and back again following the procedure.

The procedure is painless, and the entire process typically requires only one hour from your arrival at our facility until departure home. Our staff, who are well-trained and experienced, will begin to administer eye drops shortly after your arrival. Your surgeon will greet you prior to the laser procedure to answer any last minute questions you may have and to be sure that you are at ease. The experience of the procedure is not unpleasant. You are comfortably positioned in a recliner-type chair and asked to look at a soft red light during the procedure. Your surgeon will be watching your eyes very closely during the procedure. If you forget to look at the light, he will simply remind you. He will explain all the sights and sounds experienced with each step of the five minute procedure. For most patients the procedure seems to be over almost as soon as it begins. After reviewing some final postoperative instructions, you will be ready to go home. A follow-up exam will be scheduled in the office for the next day. LASIK patients routinely notice some improvement of their vision immediately, but your vision will continue to improve quickly after the procedure.

Consultation for LASIK Eye Surgery

Rom Kandavel, M.D.
Rom Kandavel, M.D.

Laser vision correction consultations are scheduled with Dr. Kandavel. Before a decision is made to proceed with laser correction, our surgeons complete a detailed review of your overall medical situation, your lifestyle and any special visual needs which you may have. A careful eye evaluation which includes computerized corneal topography and pupillography, is then performed to determine if laser vision correction is well-suited for your eyes.

Wavefront analysis will also be performed to determine if a wavefront guided treatment will be of benefit for you.

This phase of the evaluation helps our surgeons to understand your special needs and your expectations. Also it provides an opportunity to look for a medical history of certain unusual diseases or certain medications that can inhibit normal healing. Pregnant, postpartum or lactating women are asked to defer corrective procedures because of transient corneal changes normally associated with pregnancy.

A careful search for certain rare corneal conditions which may constitute a contraindication to corneal laser procedures is also conducted

Following this careful evaluation, our team will provide you with additional information specific to your particular situation that will help you to make a well-informed decision regarding laser vision correction.

Schedule an Appointment Today

Colvard-Kandavel Eye Center offers personalized eye care services for patients with routine and complex eye conditions.
Our team is here to help you make an appointment with the specialists that you need.

Schedule Now