Is irregular astigmatism on the surface of the cornea? within the flap? bottom of flap? on stromal bed? Does it vary?

What is used to identify its location?

What is the current best solution to fix assuming contacts out of the question?

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What is the current best solution to fix assuming contacts out of the question?

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Is irregular astigmatism on the surface of the cornea?

Irregular astigmatism refers to the irregular pattern of scattered light on the back of the eye, on the retina.

Nearsightedness, farsightedness, and astigmatism--the common vision problems that are correctable with glasses and contact lenses--are classifired as low-order aberrations. They result when the overall shape of the cornea is less than ideal.

The cornea is naturally smooth, but after LASIK the corneal surface may have become uneven, which will cause light rays to scatter in an irregular pattern (irregualr astigmatism) on the back of the retina. Irregular astigmatism, the irregular pattern on the back of the eye, results from an increase in high order aberrations, the uneveness in the surface of the cornea.

Microstriae is crinkling of the Bowman's layer which occurs in LASIK patients due to the anatomical disparity between the flap and stroma. Macrostriae is a complication of LASIK where small folds or wrinkles develop in the flap when it is laid back on top of the stroma. I believe both microstriae and macrostriae can contribute to irregular astigmatism. Being fitted with a rigid gas permeable lens (by an O.D. experienced in post-LASIK visual rehabilitation) can help determine if the irregular astigmatism is due to the corneal surface. Artemis ultrasound scans can also help determine if striae is present.

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What is used to identify its location?

Corneal topographies and wavefront aberrometery.

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What is the current best solution to fix assuming contacts out of the question?

It is hard to say. There are no statistics maintained on the effectiveness of retreatment to correct irregular astigmatism.

This message has been edited. Last edited by: Kurt,

Thanks for the explanation.

I just posted something alledging noone had responded to my question, before I read your response. My apologies.

Are you aware of any further advancements in determing irreg. and striae since your last post?

Who is the doctor and technology out there presently having success correcting irreg. ast.?

Any new technology on the horizon to correct irreg.?

Hello StarEyed,

You may wish to do a search for PRK. It is somewhat similar to LASIK except that the treatment is done to the corneal surface rather than under a flap.

Since irregular astigmatism is generally considered to be due to an irregular corneal surface, having further LASIK treatment is not likely to help. Some SurgicalEyes members have posted results of having PRK after LASIK.

But, the members of SurgicalEyes have not seen evidence that PRK or any other surgical treatment consistently and reliably corrects an irregular cornea.

Those who have the patience to work with an experienced contact lens fitter, and can tolerate wearing rigid lenses after LASIK, have found that RGPs or scleral lenses can help. I have worn custom RGPs since 2002 which correct over 95% of my post-LASIK visual aberrations.

Good luck,

Lynne