What are striae? (Posted: jan 2005)

There are two kinds of striae: macrostriae, which are cracks or "crinkles" in the LASIK flap, and microstriae, which are folds or crinkles in the Bowman's layer of the cornea.

What causes microstriae? (posted: jan 2005)

Microstriae are caused by anatomical differences between the flap and the stroma in LASIK. Microstriae seem to increase with the amount of correction.

What causes macrostriae? (posted: jan 2005)

Macrostriae may be caused by poor flap quality or manipulation and are also more likely to be a problem when the amount of correction is high.

What do striae mean to the patient ? (posted: jan 2005)

Microstriae are thought to have a relatively small impact on vision. Macrostriae can significantly impact vision quality and can even reduce the BCVA.

How are striae diagnosed? (posted: jan 2005)

Macrostriae can be seen in slit-lamp examination. Microstriae often cannot. I saw a video at a conference once where they were preparing to do a PRK treatment on a patient who had had LASIK. Before the procedure, the cornea appeared perfectly smooth and clear. Then the epithelium was removed in preparation for the ablation. The surface (Bowman's) appeared all crinkly, so much so that the surgeon thought it was more epithelium and kept scraping away at it. A member of the audience pointed out that it wasn't epithelium, it was Bowman's crinkles. It was astonishing how irregular it could appear when exposed versus how clear the cornea looked before exposing it.

What are the treatment options for striae? (posted: jan 2005)

Macrostriae can be treated by lifting the flap, irrigating it, stretching it and replacing it. Some surgeons also place sutures to prevent recurrence. Microstriae generally are not treated.

Where can I learn more about striae? (posted: jan 2005)

Start with our Encyclopedia listings for macrostriae and microstriae, which may have additional articles and links.