Abstract
Abstract: :
Purpose: Ortho–K is usually known as non–invasive technique to reduce myopia and astigmatism. Traditionally, it was so difficult for the keratoconus to design the ideal lens fitting to the complicated corneal shape and to maintain good condition of corneal surface. However, five years ago we started Ortho–K like procedure even for the keratoconus patients, with the newly developed lens design called OSEIRT(Ocular Surface and External Integrated Remodeling Therapy). Methods: OSEIRT was indicated for sixty–two eyes of forty–one keratoconus patients; age from twelve to forty–six. The average of their Uncorrective Visual Acuity (UCVA) before OSEIRT was 20/60 or worse, and mean Spherical equivalent (SE) was –5.43D (range –3.75 to –7.25). They were followed at least two years wearing of OSEIRT lenses during night. The following studies were examined on their auto–refraction, auto–keratometry, uncorrected and corrected visual acuity, intra–ocular pressure, corneal shape (topography), and corneal endothelium. Results: The mean SE improved to –3.24±1.98D during six months, –2.64±1.92D during one year, and –1.98±1.66D during two years. Astigmatism itself remarkably decreased. 82% of the patients improved in UCVA up to 20/30 or better, 38% of them improved up to 20/20 or better, and 12% of them improved up to 20/15. Intra–ocular pressure and endothelium remained normal. Topographically, cornea changed its shape to flatten. Corneal surface was maintained good condition. Other ophthalmologic examinations showed no abnormalities throughout the therapeutic period. Conclusions: OSEIRT/Ortho–K was evaluated to be so effective and safe even for keratoconus. However, in order to get the ideal fitting, the lens design of OSEIRT for keratoconus was needed to be completely customized one.
Keywords: contact lens • cornea: clinical science • keratoconus