Topographical Detection of LASIK Treated Donor Corneas

Abstract

Abstract: : Purpose: To determine if a portable topography unit could obtain reproducible images of donor corneas which had undergone myopic or hyperopic LASIK procedures. Methods: Seven eyebank corneas - six globes and one excised cornea were imaged using the Vistaview handheld topography unit developed by Eyesys and marketed by MARCO. The intraocular pressures were stabilized between 15 - 25 mm Hg by injecting BSS through the optic nerve in the whole globes. The epithelial surface was wetted with artificial tears. The excised cornea was imaged immediately following removal from the Optisol container. Two globes underwent a -4.0 D and -7.0 D LASIK myopic procedure respectively, using the ACS keratome and Summit Apex Plus laser. In addition, two other globes had a hyperopic LASIK procedure of +2.0 D and +4.0 D respectively using the Solan Flapmaker microkeratome and the same excimer laser. Results: Grossly reproducible images were obtained after a learning period in all corneas examined usually within 3-5 attempts per cornea. Only the post LASIK corneas showed the typical central blue flat pattern characteristic of a myopic LASIK or the central red steep pattern of the hyperopic LASIK. Conclusion: It is possible to screen donor corneas for prior myopic or hyperopic LASIK procedures using a handheld topography unit. Supported in part by Research to Prevent Blindness unrestricted challenge grant.

Keywords: 547 refractive surgery: corneal topography • 599 topography • 548 refractive surgery: LASIK