Eye Healthy Care Information

Traditional LASIK surgery achieves a simple correction of focusing power by reshaping the cornea with the aid of a laser. Wavefront LASIK is a variation of that conventional procedure and accomplishes a spatially varying correction based on readings from a wavefront sensor. In essence, a wavefront sensor measures the eye itself. It detects any aberrations by directing a weak laser source into the eye, and by sampling and processing the reflection off the retina.

Wavefront measurements reveal the irregularities of the lens, which cause optical aberrations (any deviation from a desired perfect planar wavefront). Wavefront custom sculpts the cornea to accomplish corrected vision. In many ways, Wavefront offers better results than traditional LASIK. The procedure is carried out by an ophthalmologist, with the aid of sophisticated computer-controlled equipment.

LASIK has certain potential side effects including halos or glare, which are caused due to induced spherical aberration. Wavefront has helped reduce instances of such cases where patients complain of post-operative halos or glares. A drop in such complaints is owing to the precise measurements provided by the wavefront sensor.

Thus Wavefront can help achieve a more optically perfect eye, since the corneal tissue area to be carved is measured more precisely using advanced technology and tools. But, wavefront aberrations are not the sole cause for all types of vision impairments. Therefore, Wavefront LASIK should not be treated as a panacea for all kinds of vision defects. However, eye surgeons claim that a great deal of success has been accomplished in patient satisfaction, relative to earlier refractive surgery procedures.

Though wavefront technology has been used for years by astronomers who require adjusting their telescope optics, its application to human vision has been discovered only recently. It’s true that Wavefront is a superior procedure, but it’s certainly not required by or suitable for everyone. It is imperative that you go through an elaborate wavefront diagnostic to determine if you are a potential candidate for it.

Nicola Kennedy publishes articles and reports and provides news, views and information about custom wavefront LASIK at Your Lasik Information. The LASIK Surgeons Directory will help you find a LASIK doctor.

This article may be reprinted in full so long as the resource box and the live links are included intact. All rights reserved. Copyright Your-LASIK.info

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You might have come across eye centers touting outrageous offers of “20/20 vision or your money back”. The whole concept of 20/20 vision has been ballyhooed immensely when it comes to laser eye surgery. In essence, the value 20/20 refers to a way of measuring visual acuity via the Snellen eye chart - the same old alphabet chart that you might have seen at a nearby eye care center. As an instance of Snellen measurement, people with 20/40 vision can see clearly at 20 feet what people with 20/20 vision can see clearly at 40 feet.

With the latest technological advancements in laser eye surgery, the conventional LASIK procedure has been augmented with superlative techniques like wavefront LASIK, and its add-on, iris registration. With such enhancements there is an even greater chance of 20/20 vision relative to that with conventional LASIK. By wielding wavefront technology there is a great, around 95%, chance of 20/20 vision. However, with the iris registration technology, the possibility of 20/20 vision skyrockets to an overwhelming 99%.

20/20 vision is what you aim for while undergoing any type of refractive surgery - it’s used as a benchmark. However, some people hold a somewhat dissenting opinion about 20/20 vision, as far as laser eye surgery is concerned. The argument put forth is that visual quality matters more than visual acuity. As is evident from a number of cases, laser eye surgeries, for instance LASIK, have potential complications. A patient might experience blurry vision, halos, ghost vision or double vision, glare, and starbursts surrounding light sources at night.

Normal vision is crisp and sharp. But after laser eye surgery, a person might have to deal with debilitating side effects, which typically diminish vision quality. Though the patient might still be able to decipher a 20/20 line on the Snellen chart, the vision might be blurry. Unless the complications subside, eye surgeons’ famous promise of 20/20 vision is merely a myth.

In general, the degree of refractive error and the pupil size are the only criteria while determining the candidature of a patient for laser eye surgery. Most patients are not tested on other grounds, such as contrast sensitivity, glare and depth perception. The data pertinent to such aspects is fairly anecdotal. A comprehensive preoperative test regime is necessary for achieving authentic 20/20 vision (with enhanced vision quality) after laser eye surgery.

If you find a LASIK surgery that you are confident with, you will be able to get more information about 20/20 vision.

The LASIK Surgery Directory - find a LASIK surgery. Nicola Kennedy publishes articles and reports, provides news and views about LASIK laser eye surgery and 20/20 vision at Your Lasik Information.

This article may be reprinted in full so long as the resource box and the live links are included intact. All rights reserved. Copyright Your-LASIK.info

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Presbyopia is a term that is used when a person develops difficulty in seeing up close. It is related to the use of eye muscles to reshape the natural lens of the eye to achieve accommodation. Accommodation is a when the focusing power of the lens is increased and allows a person to see images up close.

The accommodative power decreases throughout life and eventually a person will need a positive power lens to improve the near vision. These lenses are often called “cheaters”. The need for these glasses is dependent upon a person’s eyeglass prescription. A nearsighted or myopic person can often decrease the need for reading glasses by taking off his/her distance glasses.

Why is this? Well, a nearsighted or myopic person has a location up close that they can see clearly without glasses. In mathematical terms it is 1/(the eyeglass prescripton) in meters. In optical terms is the near focal point of the eye.

For many people, the loss of near vision is a frustrating experience and they seek laser vision correction for treatment. In eyeglasses, they have an option of a bifocal style lens. However, this is not possible for laser vision correction. At this time a bifocal laser treatment cannot be applied to the cornea; the tissue that undergoes the laser treatment.

What can be done? The laser can create blended or monovision. In this scenario, one eye is corrected for distance and one eye is corrected for near. The eye that is corrected for near is made intentionally myopic or nearsighted. Once this occurs the patient will function in that eye like a nearsighted person. There will be a focal point at near where the vision is clear without glasses.

The reason this is called blended vision is because the eyes work together. One eye is more dominant for distance and one eye is more dominant for near. But both eyes has some functional vision at distance and near, although each eye dominates in one area.

For many people, this is a satisfactory experience. There are many contact lens users who wear monovision contact lenses. When considering monovision laser vision correction it is important to undergo a contact lens trial. If you are unsuccessful in a contact lens trial, I would not recommend monovision laser vision correction.

If you a successful in a contact lens trial, its important to know that the monovision correction that is appropriate at the time of surgery, many not be the same correction 3-4 years later. This is because the muscles continue to fatigue and accommodation continues to worsen even after the laser vision correction. A healthy outlook is being happy with being glasses free the majority of the time. If you would only be happy with 100% glasses free for the rest of your life, then I don’t think you’ll be satisfied with monovision.

Marc Hirsch M.D. is a practicing laser vision correction surgeon. He publishes a blog http://www.visioncorrectionsurgery.blogspot.com which discusses laser vision correction information.

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