Purpose: To examine the 3-dimensional collagen fibrillar architecture of Bowman's layer after radial keratotomy (RK).
Setting: Department of Ophthalmology, Niigata University School of Medicine, Niigata, Japan.
Methods: This study used monkey eyes in which 0.3 mm deep radial incisions were made on the cornea 2 weeks and 1, 6, and 12 months before the animals were killed. Corneal buttons were immersed in a fixative and the cells macerated with sodium hydroxide 10%. Scanning electron microscopy (SEM) was performed according to standard procedures. A part of the specimens was embedded in epoxy resin for light microscopic (LM) observation for comparison.
Results: The 3-dimensional collagen fibrillar architecture of Bowman's layer was revealed by SEM. The rupture of Bowman's layer could be seen 12 months after surgery and there was no continuity of collagen fibrils in the ruptured area. In LM observations, the width of the stromal incisions gradually became narrower near 12 months after surgery.
Conclusion: Our cell-maceration/SEM method showed that the rupture of Bowman's layer remained up to 12 months after RK. This suggests that discontinuity of Bowman's layer may be responsible for globe rupture after RK.