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Old 27th Nov 2001, 03:24
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inverted flatspin
 
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Probably the best advice at the moment is to wait. A new proceedure is in development that will probably do away with most laser techniques. It is called corneaplasty and according to the Doc who is developing it, the final product will involve using eye drops to soften the cornea then a special hard contact lens to reshape the cornea and finally another set of eyedrops to return the cornea to its original firmness.

Here I have copied more detailed info.
What is Corneaplasty
Corneaplasty, is a non-surgical procedure that changes the shape of the cornea (the front part of the eye) using modern Ortho-K contact lenses as corneal molds, in conjunction with certain medications to prepare and final-set the cornea. This is a mechanico-chemical procedure.
Corneaplastytm is essentially a 3-step process. First, the cornea is “prepared” by applying a proprietary (ACS-005 enz) concentration of the human enzyme, hyaluronidase, which absorbs into the cornea, making it softer and more “malleable” for a period of time, says Hampar Karageozian, senior vice president of research and development at Advanced Corneal Systems. The drug temporarily alters the molecular bonds between proteoglycan molecules in the cornea. This enzyme has a long history of safe use in ophthalmic (eye-related) and other applications. Second, the “prepared” cornea is then molded to the desired shape with custom fitted AOK contact lenses worn during the treatment period. Thirdly, a proprietary cross-linking agent “fixative” drop is administered to “set” the cornea in its optimum shape. It effectively “glues” the collagen fibrils until they re-grout naturally.

Moreover, the procedure is reversible, i.e. it can return the cornea to its pre-altered state if desired; and, it (the cornea) is alterable indefinitely throughout life, so the procedure is repeatable. You can “fix,” “reverse” or “alter.” There is no ablation or cutting of tissue. There is only a bending of the cornea and a migration of corneal epithelium.

The term “Corneaplasty,” as determined by the U.S. Department Of Commerce Patent And Trademark Office, is merely a conjunction of the two descriptive words, “cornea” and “plasty.” Corneaplastytm (both REFRACTIVE CORNEAPLASTYtm and THERAPEUTIC CORNEAPLASTY), are marks sought after by the founding company, Advanced Corneal Systems, and are defined as follows:

REFRACTIVE CORNEAPLASTY: Goods and services to non-surgically change the deficient vision in a healthy eye by changing the shape of the cornea in individuals suffering from refractive error including myopia, hyperopia and astigmatism.

THERAPEUTIC CORNEAPLASTY: Goods and services to non-surgically change the shape of a damaged or diseased eye in individuals suffering from optic diseases such as ocular herpes, keratoconus, or extreme astigmatism resulting from corneal transplant surgery or cataract surgery.

The Attorney for the Trademark Trial and Appeal Board (T.T.A.B.) contends that the word “refractive” is a descriptive adjective that refers to correcting refractive errors of the human cornea. The applicant’s (ACS, Inc.) “pharmaceutical preparations” have a refractive purpose, because they are used to correct refractive errors of the eyes. So, for now, we have a new non-surgical category of refractive correction, know as “corneaplastytm,” which may or may not undergo a future semantic change.

The Procedure:

This is the probable case scenario.

The treatment period lasts approximately 2 weeks with 5–7 patient visits.

Day 0: Patient examined, then trial fit with AOK lenses, then enzyme administered and patient sent home.

Day 1-3, or when cornea is prepared: Patient returns and lenses are dispensed. This procedure will most likely be a Nightwear, End Result Ortho-k (NERO, a term coined by Roger Tabb, O.D.) or worn daytime and removed at night. Expect 4-5 diopters change from 8 hours to a few days. 1-3 diopters can change in a matter of hours.

Day 4-10: Stabilizing drops or gel is administered by the patient QID (4 times a day) in conjunction with a custom contact lens retainer.

Day 11-14: D/C stabilizing drops and lenses when stroma is altered and “set” to new desired contour.

Since the procedure deals with altering the stroma, greater degrees of refractive change are possible, as compared to Ortho-K, which only deals with about a 50 micron layer of epithelium.

The procedure can apparently be repeated, if necessary, throughout one's lifetime of refractive changes, without any damage done to the cornea. The tissue is said to remain pristine, as the hyaluronidase only temporarily alters proteoglycen bonds between the lamellae to soften the tissue, and does not actually affect the collagen lamellae themselves.

Who started Corneaplastytm?
Corneaplastytm is the brainchild of Advanced Corneal Systems (renamed ISTA Pharmaceuticals, Inc. in July 2000), Irvine, CA 92618; (949) 788-6000; (949) 788-6010 fax., the proprietary company seeking patents and marks initiated circa 1994. Introduced to the international community, circa 1995, lectures by Ortho-K pioneers such as Don Harris, OD, Charles May, OD and Stuart Grant, OD, presented materials and unpublished information at UAB and NERF conferences. At that time, mathematical functions for corneal molding, including tear layer plots, design comparisons, and computational methods were also discussed by such notable optometrists as Jim Day, Roger Tabb, the Roger Kame, and Joe Barr.

Where Is The FDA Investigational Status?
In the off-shore clinical trials that started in January 1994, phase I and II have been completed in 1997 and 1998 and yielded exceptionally good results. Expected in the first quarter of 2000, large scale clinical studies will enter 3rd phase in US and so far, right on track. Optimum lens design as well as dose/response studies are ongoing. A new stabilizing agent has been added to the trials that dramatically shorten the time from months to weeks to stabilize the cornea after it has been reshaped. Reducing the recovery time should also limit noncompliance.

When Will Corneaplastytm Be Available?
The large pharmaceutical company, Sandoz, is helping Advanced Corneal Systems, through the FDA clinicals. They expect approval (from what I have been led to believe) within a year or two. They are also working on an alternative drug delivery systems such as a "needle patch," to try and keep this procedure totally within the scope of optometry.

Why is Corneaplasty So Significant?
Extremely low complication rate, especially when compared to refractive Surgery. Corneaplasty is a Non invasive, non-surgical, procedure. The cornea is never cut and no tissue is ablated. There is no pain, no risk of infection, haze, starbursts, double vision, glare, ghosting, etc. associated with laser or other refractive surgeries. Anthony B. Nesburn, MD, director of Ophthalmology Research Laboratories at Ceders-Sinai Medical Center and clinical professor of ophthalmology, Jules Stein Eye Institute, University of California, states, “The beauty of this technique is that Bowman’s layer remains intact.” His studies indicated that the collagen fibrils themselves are untouched, just the substance that holds them together is affected. Nesburn added that the clarity of the cornea is unchanged pre- to post-treatment.

An additional noteworthy benefit is that the new corneal surface is more pristine than ever before. That is to say that the corneal molding smoothes out the natural anatomical undulations found on the cornea and facilitates an improvement in VA to 20/10ths (i.e. two lines better than 20/20) in some cases. The treatment zone with Corneaplasty is bigger and better than LASIK.

How Much Will This Procedure Cost?

The cost for this procedure is significantly less that LASIK and PRK because there are no laser, facility or royalty costs. However, just like all new procedures, the cost will be in line with what the free market allows. It will probably range from $750.00 to $1,250.00 per eye to begin with, roughly half the cost of LASIK. Enhancements and further alterations will carry modified fee schedules.

The major deterrent to LASIK is both cost and fear related. Corneaplasty is safe, effective and relatively inexpensive. It is destined to become more main stream than the invasive surgeries existing now. As it becomes more commodity-like and delivered in a more ubiquitous fashion, costs will seek a lower level.
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