LASIK Refractive Eye Surgery | Vision Update Ezine

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For people over the age of forty, reading becomes increasingly difficult. This inability to focus up close is called Presbyopia. It is a normal part of aging, and can not be prevented. As LASIK and PRK have increased in popularity, researchers have looked for ways to eliminate the need for reading glasses for those over 40.

Until recently, the options have been limited to mono vision LASIK, which is still the most selected option among refractive surgery patients. It involves surgically correcting one eye for the distance, and the other for near. While it is a viable option, there are still those who can not adjust to the difference in visual acuities between the two eyes. In those cases the near eye must be re-corrected for the distance, and reading glasses are required.

Another option has been a multi focal intraocular implant. It is basically a cataract operation, with an implant that has concentric rings of refractive power. One power is for the distance and the other for near. Again, there are those that are happy with the total vision, but many still complain of a lack of complete visual acuities at the distances they require. Also, glare and poor night vision are common complaints.

A relatively new procedure to attempt to address these issues, is called CK or Conductive Keratoplasty. It involves using radio waves to steepen the cornea of an individual who sees well in the distance, but wants to have better near vision. It creates a nearsighted shift in one eye and is essentially the same as mono vision with LASIK or PRK. The results will vary as well. Thus, with out a complete and very successful procedure for all patients the search continues.

The newest procedure, which is still in clinical trials, is called a Corneal Inlay. It involves lifting a flap in the cornea similar to LASIK, and placing a bio compatible disk in the middle of the tissue. It is done in one eye only and is similar to a disk with many pin holes in it. The pin holes increase the depth of field in that eye, and increases one's ability to see at near. The test results are still incomplete, although initial data seems to indicate that there is less visual discomfort. One problem exists if the patient has a light colored iris, it will appear dark after the implant is inserted. The disk is removable simply leaving a surgical scar behind. The current clinical trials are using an Acufocus ACI 7000 implant. Only time will tell if this procedure will let all of us 'old folks' get rid of our reading glasses.

Aging is a fact of life and all the trips to the gym, nutritionist, and Dermatologist for Botox, will not prevent your eyes from needing reading glasses when you approach the ripe age of 40. While multifocal eye glass lenses have been around for many years, recent developments in contact lenses now permit comfortable, clear vision in the distance and at near.

In years past, bifocal contact lenses fell short in their goal of clear distance and near vision because of limitations in the technology. Common complaints included poor distance or near vision, glare, fluctuating vision and discomfort. Most people had to sacrifice some visual acuity and comfort in order to avoid reading glasses with the contact lenses. Some eye doctors even fit patients with Monovision, which is the wearing of one distance and one near contact lens. While in concept it seemed acceptable, in clinical practice it most often resulted in visual discomfort in the distance, near or both. In addition, monovision results in the elimination of binocular vision and thus depth perception. In my practice, only approximately 20% of these patients were happy with their vision.

Fortunately, today there are better alternatives. The ability to combine spherical and aspheric curves results in a gradual change in power from the distance to near and a more natural visual experience. In addition, the biggest development in this arena is the ability to correct astigmatism as well as near and farsightedness along with the near prescription. While there are several lenses available, I have found the Ultravue 2000T progressive soft contact lens the be the best. The edge design and availability of parameters makes it great for most patients. Once the eye doctor becomes familiar with the subtleties of the lens, fitting is straight forward and the results are spectacular. There are several Gas Permeable lenses also available and have wonderful results as well. My favorite is the Aspheric Progressive Multifocal from ICL. Fitting is more difficult, but for the right candidate, the results are outstanding.

In short, if you wear contact lenses and are having trouble reading with them in, ask your eye doctor for the new multifocal contact lenses. They will turn back the clock and make contact lens wear great again. We fit well over 95% of our patients over 40 with one of these lenses. We can't keep your eyes young, but we can keep them seeing well.

Cataract surgery has undergone a remarkable evolution over the many years since itâ%u20AC%u2122s inception. At first, a large incision had to be made so the natural lens could be removed and an Intraocular Lens (IOL) could be inserted. The first IOLs were placed in the anterior section of the eye in front of the iris. This dramatically improved the procedure from the time when there were no implants. The problem with these anterior segment IOLs were that they vibrated resulting in endothelial (inner most layer of the cornea) damage often requiring corneal transplants.

The next big advancement was the development of the posterior IOL. This implant was place behind the iris thus eliminating the vibration and therefore protecting the cornea. These still needed a large incision requiring 7 sutures. The next big step forward was Phacoemulsification. This required a small incision through which a tube was placed, and the natural lens could be sucked out in pieces. Then a fold-able lens implant was placed in the eye behind the iris. This procedure only needed 1 suture.

A major issue with all of these implants is that they require the use of reading glasses in order to see close, or read. Over the years, many types of multi focal implants were tried. They had concentric rings, multiple focal zones and other creative attempts at permitting the patient to see clearly both near and far, without the use of reading glasses. They all failed in part because of glare, and the lack of clarity at some distance.

The newest lens is called The Crystalens Accommodative Lens. It is a revolutionary concept that mimics the natural lens. The natural lens that we are born with is attached to the ciliary muscle by a series of small fibers called Zonules. The ciliary muscle contracts, causing the lens to change shape via the zonules. That is how we accommodate, or focus our natural lens. During cataract surgery, the zonules are broken and the implant has NO attachment to the ciliary muscle. The Crystalens bypasses the needed attachment with a new concept in accommodation. It is placed in the posterior chamber behind the iris just like older IOLs, but itâ%u20AC%u2122s unique design permits focusing.

Most implants are held in place by little side arms call haptics that go out horizontally. The Crystalens has haptics that are attached to the central part of the implant by hinges. These hinges permit the implant to move forward and backward changing the focal point of the light. This mimics what effectively takes place with one's natural lens. It is the only lens of itâ%u20AC%u2122s kind. However, it does take some work to have it work properly. Following surgery the patient is expected to read at least 6 hours per day for a number of weeks to position the implant properly, and get the ciliary muscle used to physically pushing the implants haptics forward and back. Failure to do so will result in poor focusing ability.

Statistics thus far show that 98.4% of Crystalens implant patients are able to read newspapers comfortably (although which newspaper they do not say) and 100% of these patients say they can see computers and car dashboards clearly. 98.4% of these same patients also say that they are able to see 20/40 in the distance or better with out eye glasses. These are statistics reported by the manufacturer and may vary as more individuals have the implants. Time is always the best indicator as to how effective a new procedure is.

This surgery has already been expanded to include patients that don't have cataracts but are older then 40, and need reading glasses. This implant would eliminate that need forever. So far the results are mixed. There are those that love the final vision, and there are those that are not totally thrilled. As with all procedures, realistic expectations are a requirement for a completely satisfied patient. It should be noted that most surgeries today replacing the natural lens are sutureless, since a small incision is placed in the cornea through which the natural lens is removed and implant inserted.

Before undergoing this or any other surgery all patients must know what to expect and understand that nothing is as good as the equipment that we are born with.

A 40 year old male went for a LASIK consultation and was told that he would be a great candidate for the procedure. He had complained prior to surgery that he had very dry eyes and often woke up with painful eyes, but the surgeon told him that he would still do well with the procedure.

During the course of the surgery the flap kept folding over and sticking to itself resulting in multiple wrinkles called striae. When the surgery was over the outer most layer of the cornea appeared to be dry resulting in a mild corneal abrasion. Therefore a bandage contact lens was place on that eye as a protective measure. The patient called the office early the next day complaining of EXTREME pain and light sensitivity and was instructed to come right in. Upon evaluation it was determined that there was a large abrasion resulting in the edge of the flap lifting up. There were also multiple striae in the flap which caused substantial visual decrease.
Since the abrasion was present it was decided to leave the lens on for another 24 hours and to reevaluate the eye the next day. On the next follow up, there were more striae present and the vision was now down to 20/200. To improve the refractive surface and improve the vision, the corneal flap was "re floated" to flatten it out and eliminate the striae. This was accomplished, but during this procedure the entire outer layer of the cornea pealed off. Aside from being extremely painful this further reduced the vision. While the flap was now smooth, it lost the epithelial layer. Another bandage contact lens had to be reapplied until the epithelium grew back.

Two days later the patient returned, still in pain, still blurry. The epithelial layer had regenerated and was beginning to cover the cornea again. Unfortunately, it was also growing under the cornea which required going back into surgery to once again lift the flap to clean out these cells. Once again, the outer layer came off and needed another contact lens. Finally after 10 more days, the epithelium regrew and the pain was eliminated. However, the central cornea was now hazy and the vision was still 20/200. Pred Forte steroid eye drops were prescribed to treat this new problem.

This individual also suffered from severe allergies and constantly had the need to rub his eyes. After fighting the feeling for several weeks, in his sleep he gave in and rubbed his eye ...vigorously. Feeling substantial pain he woke up to notice that he could not see out of that eye. Early the next morning he once again returned to the office with a red, painful, blurry eye. An examination disclosed that the cornea flap had been torn off the eye and was no where to be found. With out the flap, there was no hope of helping this cornea and an emergency corneal transplant had to be performed. This was accomplished and many months later the patient had his vision restored with a noticeable degree of astigmatism. He was fit with a custom designed contact lens which restored his vision to 20/30.

While this case scenario is quite unusual and fortunately is a rare occurrence, any one considering refractive surgery must consider that it may occur to them. It may not be as a result of the surgeon or the follow up care, but simply a series of bad side effects that could happen to anyone. In short, all candidates must be aware of all the potential complications and be willing to accept them if they occur.

Macular Degeneration is an ocular condition whereby the central part of the retina called the Macula, breaks down resulting in decreased vision. Usually a genetic predisposition is required for the condition to occur and the severity will depend on both genetics and environmental factors. Studies have long concluded that factors such as drug use and smoking will precipitate the disease to occur at earlier ages and will substantially make the vision worse. Smoking will increase the likelihood of the condition occurring 300% and will also make it much worse then in an individual that never smoked.

Recent studies have concluded that other factors never before associated with the condition may also be contributing causes to the disease. Certain types of carbohydrates have conclusively been associated with the condition. Specifically, foods rich in carbohydrates that have a high glycemic index have been linked to Macular Degeneration. This factor raises the blood glucose level and is a measure of how fast the carbohydrates are metabolized. The faster the food is broken down the higher the glycemic index.

Foods made from simple carbohydrates like cake and white bread or ones that are sweetened with sugar or corn syrup metabolize very quickly pouring glucose into the system. Complex carbohydrates like fruits and vegetables break down more slowly and result in a steadier release of glucose into the system. Complex carbs are much better for timed release of energy for active people since it keeps fueling the system. It also uses the glucose as it is released thus decreasing the likelihood of having to store it in cells. This of course results in an increase in fatty tissue.

Intake of foods with a high glycemic index causes conditions such as diabetes, hypertension, vascular disease and certain types of cancers. The American Journal of Clinical Nutrition has published studies correlating these foods and conditions. One such study stated that individuals that ate a lot of high glycemic index carbohydrates had as much as a 40 times greater chance of developing macular degeneration and that the severity of the condition would be worse then those that did not eat that class of food.

The theory behind the correlation between the high glycemic index carbohydrates and macular degeneration stems from it's impact on the smaller blood vessels. High blood glucose like in diabetes weakens the cellular bonds in the blood vessel walls. This in turn weakens the vessel's ability to maintain good blood flow thought the vessels. As a result the blood leaks out of the blood vessels resulting in damage to the surrounding tissue. In addition, the end organs are not going to get the full supply of blood. It can be compared to a garden hose that leaks water all along the hose. As a result the sprinkler will not get enough water and the grass at the end will turn brown. Also, the areas along the hose will flood damaging those parts as well.

In summation, there are many factors that can contribute to macular degeneration, but recent studies show that simple carbohydrates increase the likelihood of contracting and the severity of the condition. As with most disorders, eating the proper food will keep you healthier and prevent some conditions.