Refractive Surgery

We removed previously implanted convex hydrophilic lenses of 1/2–55% hydration from six eyes in six baboons 3–6 months following initial implantation, using standard keratophakia techniques. Subsequently, we replaced three of the lenticles with convex or concave lenticles. There were no surgical complications during lens removal or lens replacement. The implanted low-water-content lenticles were not tolerated by the corneas and had to be removed, whereas the hydrophilic lenticles which were reimplanted were well tolerated. The excised hydrophilic lenses were structurally intact; only the low-water-content lenses were coated with adherent keratocytes and collagenous material. Following lenticle removal, the recipient corneas returned to preoperative parameters. This study demonstrates the technical feasibility of intrastromal lens removal and/or exchange for the modification of refractive errors.