Radial keratotomy in non-human primate eyes.

We performed a prospective study of the effects of radial keratotomy in the owl monkey. We compared a 16-incision and an eight-incision radial keratotomy, and followed the changes in corneal curvature, corneal thickness, endothelial cell counts, and intraocular pressure. We compared the results of the changes in these clinical factors with a histopathologic and ultrastructural analysis of the time-related changes after radial keratotomy in another group of animals. We found that the loss of initial corneal flattening following radial keratotomy corresponded with the contracture of the wound as demonstrated by histopathologic and ultrastructural study. This procedure results in a significant endothelial cell loss (14% to 15%), which is a result of the postsurgical inflammation associated with this surgery. Additionally, examination of the histopathologic structure of these corneas showed a high level of variability in the surgical incision depth, which we believe is responsible for the marked variations in the response to the surgical procedure.