In the United States, contact lens solutions must go through a rigorous approval process performed by the FDA in order to make it to the drug store shelves. This process includes multiple patient clinical tests, pharmacology evaluations, adverse reactions, and careful protocol (instructions to patients) considerations. By the time the solutions reach our medicine cabinets, they are supposed to be safe, affective and easy to use. That all sounds great, except for the one fact that can not be fully evaluated in clinical trials. How will consumers actually use the solutions? Will they do exactly as they are supposed to, or will the cut corners to save time and money?

The sad fact is that consumers are non-compliant, and do not follow the instructions as they are supposed to. This leads to eye irritations, infections, red eyes, and ulcers of the eye.

Back in the old days, patients had to first make their own saline solution by mixing distilled water with a salt tablet. Unfortunately, many individuals did not use distilled water because they had to buy it; instead used tap water filled with bacteria and impurities. This ultimately led to severe problems. Additionally, problems arose with the saline tablets, and were soon removed from the market. The second step was to use a daily cleaner every day, and then rinse the lenses off with the saline solution. Next the lenses had to soak in a disinfecting solution to kill bacteria for a minimum number of hours per day. Frequently, that step fell short, because the individual wanted to wear the lenses prior to fully disinfecting them. Thus they reinserted the contacts before they were fully cleaned. The final step in this adventure was to enzyme the contacts at least once per week to remove protein deposits. That required buying yet another product, and soaking the lenses again. The enzyme pills were quite expensive, and were often not used appropriately. Another issue was that one of the main types of enzyme tablets was made from pig pancrease, and could not be used by any one who was kosher. The bottom line was that despite having a carefully laid out protocol for use, a number of these steps were not followed due to expense, and lack of convenience.

Today’s solutions are much simpler; they are multipurpose, single step and no rub. That simply means that they clean, disinfect and enzyme all at the same time, and the lenses do not have to be rubbed in order to remove surface debris. So the question that begs to be asked is why people still have problems cleaning their contact lenses? The answer is simply that there is still a protocol for use, and consumers tend to look for short cuts. The correct use of these new solutions requires that every day the old solution be discarded, and the case be cleaned. Fresh solution must be used when the contacts are removed for cleaning. Furthermore, patients are instructed to wash their hands prior to handling the lenses. Here lie the following problems:
1) patients don’t always wash their hands. They think that sticking their fingers in their mouths is an acceptable alternative to soap and water.

2) Patients do not discard the solution daily after each use, and the reason is simple. Solution is expensive and reusing it saves money. The efficacy of the solution is dramatically reduced after each use and is contaminated each time it has a lens submerged in it.
3) The contact lens case must be cleaned after each use. When the contacts are removed, the case must be cleaned in order to eliminate the dirt, bacteria and other undesirable agents left behind after use.

The contact lens solution manufacturers go out of their way in order to make a safe, and affective way to clean contact lenses. However, it requires patients to read and follow the instructions, and above all use common sense. That is the one factor that the FDA can not guarantee.

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Those of us old enough to remember watching Star Trek on TV can think back to how Dr McCoy used to treat all of his patients. He would wave an instrument over the patients affected area and cure them in seconds. At the time it was purely science fiction, but today it is reality.

A new instrument called the Femtec Laser manufactured in Heidelberg, Germany was designed to perform just such a procedure. The laser focuses on the inside part of the cornea called the Stroma, and makes refractive changes without cutting the outer layers. This avoids surgical complications often found with flaps in LASIK and surface ablation with PRK. No anesthesia is required thus avoiding an additional source of complications, and there is no risk of post surgical infections since there are no wounds to heal. The procedure is completely intrastromal (below the top layer of the cornea) avoiding any contact with the top layer of the cornea.

Presurgical measurements include Keratometry(curves of the cornea), refraction(prescription) and corneal thickness. Then a customized photodisruption pattern is designed for that patient. The laser must use an interface surface to help conduct the laser, and employs a sterile contact lens.

To date the procedure has only been used to correct presbyopia (the over forty years old reading issue) not near or farsighted patients. The results have been fairly good improving patient’s reading ability from about 20/70 (J8) at near to 20/25 (J3-J2). The surgery does not affect the distance vision. The only patient complaint has been haloes and glare which appears to resolve in approximately 1-2 months.

While this new surgical laser is still in the infancy of development, it opens the door to a whole new level of medical treatment.

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PRK, is a refractive procedure that reduces, or eliminates the need for eye glasses. It involves removing the Epithelium, or outer layer of the cornea by applying alcohol to the treatment area which weakens the cell’s attachments to each other. This is followed by brushing aside these dead cells exposing the inner layers of the corneal tissue. The most important zone is the stromal layer. Next, an Excimer laser is employed to ablate or vaporize a specific amount of stromal tissue, reshaping the corneal in such a way as to change the refractive power of the eye.

If an eye is nearsighted, then the cornea will be made flatter. If it is farsighted, then the cornea will become steeper. Finally, if there is astigmatism the reshaping will be according to the axis or orientation of that power.

Following the surgery, a bandage contact lens is applied in order to facilitate the regrowth of the epithial tissue. The lens acts to aid the regeneration of cells, and keeps the patient more comfortable during this healing process. The contact must be removed after approximately 3-5 days, but may be left in longer if more healing time is required. Antibiotic eye drops are used to prevent infection, and topical steroids are also used to aid the healing, reduce inflammation and prevent scarring of the cornea. The steroids will be used for at least 4-6 weeks, but may be continued if needed.

One complication that often arises is hazing of the cornea. This may be precipitated by UV light, or a natural process as a byproduct of the increased rate of metabolism. When seen in the healing patient we usually increase the dosage of topical steroids, and closely follow the patient and their intraocular pressure. Most often, this treatment will reduce or eliminate the haze, and the patient’s vision will be fine. If not, frequently the individual will complain of blurry vision, doubling or shadows in their line of sight, and glare or hazy vision.

In cases where the steroids do not effectively eliminate the corneal haze, additional surgery is required. In those cases the laser is re-employed to brush away the outer hazy layers in the hope that when the cornea heals it will be clear. Steroids are used during this second healing period. These treatment modalities most often get the results we want, and the patient has clear corneas. In extreme cases, even the second laser therapy does not eliminate the corneal haze. In those cases if bad enough, a corneal graft may be required. Fortunately, that is extremely rare.

A final note; if an individual experiences corneal or visual haze following PRK, they should immediately return to their surgeon for follows up care. The sooner it is treated the better the results will be with the least amount of discomfort will be experienced.

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