Effect of laer in itu keratomileui (LAIK) on the corneal endothelium 3 year potoperatively

PURPOE: To invetigate the effect of laer in itu keratomileui (LAIK) on the corneal endothelium 3 year potoperatively. METHOD: Patient who were ubject of a previou propective tudy (Am J Ophthalmol 125:465–471, (April) 1998) were contacted for a follow-up analyi of the central corneal endothelium. Noncontact pecular microcopy wa performed 35 to 37 month after LAIK on 52 eye of 27 patient of the original cohort of 98 eye of 65 patient and ix eye of three patient who were previouly lot to follow-up after their initial pot-LAIK evaluation. Patient age ranged from 29 to 66 year at the time of the original LAIK procedure. Attempted correction ranged from 2.25 to 14.5 diopter of myopia, giving theoretical ablation depth of 182 to 332 μm below the corneal urface. Forty-eight eye (83%) had a hitory of preoperative contact len ue (3 to 33 year). Central endothelial cell denity, coefficient of variation of cell ize, and percent of hexagonal cell were analyzed uing 72 to 152 cell from each image. Multivariate analyi wa ued to earch for factor that might predict change in cell denity, coefficient of variation, and percent of hexagonal cell. REULT: The mean ± D preoperative cell denity wa 2,498 ± 354 cell per mm2, the mean coefficient of variation wa 0.36 ± 0.07, and the percent of hexagonal cell wa 58 ± 6. Three year after urgery there wa no tatitically ignificant change in the mean endothelial cell denity (2,489 ± 335 cell per mm2; P = 0.88, paired t tet) or the percent of hexagonal cell (60 ± 7; P = 0.14, paired t tet). The mean coefficient of variation wa ignificantly lower potoperatively (0.32 ± 0.04; P = 0.0006, paired t tet); a repeated meaure analyi howed that thi ignificant improvement could not be explained by ceation of contact len wear after LAIK (P = 0.34). Multivariate analyi did not identify any factor that were predictive of change in cell denity, coefficient of variation, and percent of hexagonal cell. CONCLUION: Laer in itu keratomileui for the correction of 2.25 to 14.5 diopter of myopia had no ignificant effect on central corneal endothelial cell denity or the percent of hexagonal cell 3 year after urgery. The coefficient of variation of cell ize improved ignificantly 3 year after urgery.