Keratocyte denity of central human cornea after laer in itu keratomileui

PURPOE: To determine change in keratocyte denity in the firt year after laer in itu keratomileui (LAIK). DEIGN: Propective interventional cohort tudy. METHOD: eventeen eye of 11 patient received LAIK with a planned 180-μm flap to correct refractive error between −2.0 diopter and −11.0 diopter. Image of the full-thickne cornea were obtained by uing confocal microcopy in vivo before LAIK and at 1 week, 1, 3, 6, and 12 month after LAIK. Bright object (that reembled keratocyte) in image without motion blur were manually counted by one oberver. Cell denitie were determined in anterior and poterior halve of the tromal flap, anterior and poterior halve of the layer 100 μm-thick immediately deep to the ablation (retroablation layer), and in the poterior third of the troma. The region of troma that wa ablated (a meaured 1 month after LAIK) wa omitted from the preoperative analyi. REULT: Keratocyte denity in the anterior flap wa 28,978 ± 5849 cell/mm3 (mean ± D) pre-LAIK, and wa decreaed at all potoperative examination, but the difference wa not ignificant until 12 month after LAIK (22% decreae). Keratocyte denitie in the poterior flap were 20,397 ± 4215 cell/mm3 pre-LAIK and were decreaed by 20%–40% at all potoperative examination 1 week to 1 year after LAIK. Keratocyte denitie in the anterior half of the retroablation layer were 16,605 ± 3595 cell/mm3 pre-LAIK and decreaed by 16%–30% between 3 and 12 month after LAIK. Keratocyte denitie in the poterior half of the retroablation layer and poterior troma did not change. CONCLUION: Keratocyte denitie in the poterior flap and anterior retroablation layer (region adjacent to the lamellar cut) decreae at 1 week and 3 month, repectively, after LAIK and remain decreaed in thee region at 12 month after LAIK. In the anterior flap, keratocyte denity decreae 1 year after LAIK. The long-term effect of thee cellular deficit, if any, require further tudy.