Recurrence of corneal dystrophy resulting from an R124H Big-h3 mutation after phototherapeutic keratectomy

Purpose. The purpose of the study was to investigate the recurrence-free interval after phototherapeutic keratectomy (PTK) in patients with corneal dystrophies resulting front an Arg124His (R124H) mutation of the Big-h3 gene. Methods. Patients with corneal dystrophy resulting from a genetically confirmed Big-h3 R124H mutation were examined with a slit lamp, The patients were divided into two groups on the basis of the Mutation genotype, and the recurrence-free interval was analyzed. Results. In the 4 eyes of 3 homozygous patients, the mean. (+/- standard deviation [SD]) recurrence-free interval was 9.5 +/- 3.1 months, whereas in the 7 eyes of 4 heterozygous patients it was 38.4 +/- 6.2 months. The former interval was statistically shorter than the latter (Kaplan-Meier survival analyst,, with log-rank test, p = 0.004). Conclusions. These results strongly suggest that the mutation genotype of Big-h3 gene determined the recurrence-free interval as well as the clinical picture after PTK. Therefore, PTK should be considered for patients with Big-h3 R124H corneal dystrophy, on the basis of the expected recurrence-free interval deduced from molecular analysis of the zygosity of the Big-h3 R124H mutation.