Screening for Prior Refractive Surgery for Corneal Donation

ABSTRACT

PURPOSE: To provide fundamental data for screening for prior refractive surgery in donor cornea. METHODS: The corneal curvature map and pachymetric measurements were analyzed in 68 eyes that had undergone corneal refractive surgery. Differences in the corneal curvature of the center and periphery, differences in the corneal thickness of the center and periphery, and the shape factor on the curvature map in postoperative eyes were compared with preoperative measurements. RESULTS: Measurement of the central corneal curvature subtracted from the peripheral corneal curvature was -1.64 +/- 0.71D in the preoperative eyes and 3.10 +/- 1.68D in the postoperative eyes. With a criterion of -0.23D, the sensitivity and specificity were 100% and 98.5%, respectively. The shape factor was 0.24 +/- 0.09 in the preoperative eyes and -0.82 +/- 0.45 in the postoperative eyes. With a criterion of 0.058, the sensitivity and specificity were both 100%. Measurement of the central corneal thickness subtracted from the peripheral corneal thickness was 97.60 +/- 25.42 micrometer in the preoperative eyes and 163.47 +/- 38.5 micrometer in the postoperative eyes. With a criterion of 123.0 micrometer, the sensitivity and specificity were 89.7% and 88.4%, respectively. CONCLUSIONS: Regional differences in corneal curvature and shape factor may be very useful parameters in screening for prior refractive surgery in donor cornea. The difference in corneal thickness may also be a useful parameter.