Underestimation of corneal thickness by Orbscan after myopic correction. 15519055

摘要

In the reply1 to a letter about the article on corneal thickness measured by Orscan (Bausch & Lomb) ,2 Miyata could not satisfactorily explain why the corneal thickness was underestimated after myopic LASIK. In the article, Miyata et al. speculated that the reasons were changes in the refractive index, stromal haze, changes in the anterior contour of the cornea, and inappropriate reconstruction algorithms that might occur after LASIK. We propose another explanation of the underestimation of corneal thickness measured by Orbscan after myopic LASIK.The posterior surface of the cornea is observed through a lens composed of the overlying epithelium and stroma. The lens changes its shape and thickness after myopic LASIK. Then, the posterior surface of the cornea observed through the lens becomes relatively smaller than that observed before the surgery.