Has anybody tried Ortho-K or CRT contact lenses?

[ddc]

Hello,

My eyes have finally gotten to the point where I think they are starting to interfer with my shooting. The target is very blurry even as close as 7 to 10 yards. Even at 7 yards I can't detect the bullet holes in the target if they are in the black. I've considered LASIX and other similar procedures but I'm just not ready to let someone operate on my eyes.

Ortho-K and CRT (Corneal Refractive Therapy) refer to two similar procedures where you wear special contact lenses while you sleep but do not have to wear them during the day.

The lense reforms the cornea during the sleeping hours and then the cornea gradually returns to it's original shape during the day. Apparently the regression is slow enough so even the following evening your vision remains improved; sometimes to a considerable degree. Some people don't even have to wear the lenses every night.

It sounds like an alternative for those who are not quite ready to let someone operate on their eyes.

Has anybody had any experience with this procedure?

Thanks,
DDC.

 

[BluesBear]

Hmmm I need to see my eye-doc and get a refill on my contacts. I'll ask him.
Sounds interesting.

 

[ejohne]

From the American Academy of Ophthalomolgy:

Orthokeratology, also called Ortho-K, precise corneal molding (PCM) or controlled kerato-reformation (CKR) is a non-surgical treatment that uses special contact lenses to reshape the eye's cornea and improve vision in people with myopia and astigmatism.

In orthokeratology, patients wear a series of specially designed contact lenses for several hours per day to gradually change the shape of the cornea over a period-usually about three to six months.

After the desired shape of the cornea is achieved, patients must wear retainer lenses for a prescribed time every few days. If retainer lenses are discontinued, the cornea and the patient's vision return to their original state.

Orthokeratology may be practiced by either optometrists or ophthalmologists (Eye M.D.s).



Why Is It In The News?

With the growing popularity of surgical vision correction procedures, orthokeratology has been widely marketed as a non-surgical alternative.

There is debate in the eye care community over whether the procedure is safe and/or effective.

Proponents claim it is a reversible, non-surgical alternative to wearing eyeglasses or regular contact lenses.

Some physicians feel it is not an effective method of vision correction because it requires continued wear of the retainer lenses and that patients require more intense monitoring than is normally acceptable because the result is unstable and unpredictable.



Facts & Statistics

The FDA, which regulates contact lenses as medical devices, has not approved any specific contact lenses designed especially for orthokeratology.


Reductions in nearsightedness treated with orthokeratology are temporary, and vision will return to its previous state when the patient stops wearing retainer lenses.1,2,3


No scientific evidence exists that the shape of the cornea can be permanently changed by wearing retainer lenses.4


Although new techniques may improve predictability of orthokeratology results, practitioners cannot predict patients' individual responses to the procedure, such as how much correction of vision may be achieved or how long it will last.4


Orthokeratology typically results in a small reduction in nearsightedness, however most nearsighted people require greater degrees of correction to attain 20/20 or 20/40 vision.4


Overnight use of contact lenses, as may be prescribed in orthokeratology, carries a risk of serious complications, such as corneal infections.5


Conclusions

Until further studies are conducted to ascertain or improve predictability and efficacy, the risk of complication outweighs the benefit orthokeratology offers patients. The majority of patients are better served through eyeglasses, contact lenses or vision correction surgery.



References

Wilson DR, Keeney, AH. Corrective measures for myopia. Surv Ophthalmol 1990 Jan-Feb; 34(4):294-304.


Polse KA, Brand RJ, Vastine DW, Schwalbe JS. Corneal change accompanying orthokeratology. Plastic or elastic? Results of a randomized controlled clinical trial. Arch Ophthalmol 1983 Dec; 101(12):1873-8.


Binder PS, May CH, Grant SC. An evaluation of orthokeratology. Ophthalmology 1980 Aug; 87(8):729-44.


Federal Trade Commission. Facts for Consumers: Vision Correction Procedures. 1997.

 

[Justin]

Hey all.
As this isn't really a gun-related thread I'm going to close it down.
However, for those still interested, I'd recommend either sending a message to ejohne, or doing a Google search on the references in the essay that he posted.