Corneal Endothelial Cell Loss 9 Years After Excimer Laser Keratorefractive Surgery

Early clinical outcomes, including efficacy and endothelial cell loss, of refractive lenticule extraction using a 500 kHz femtosecond laser to correct myopia

“…We found no significant cell loss postoperatively, a result comparable to the outcomes after excimer laser surgery, such as LASIK and photorefractive keratectomy (PRK). 12,13 Patel and Bourne 12 found that the corneal endothelial cell loss 9 years after LASIK and PRK did not differ from the agerelated cell loss found in normal corneas. Smith et al 13 found that the ECD decreased, but not significantly (from 3011 G 329 cells/mm 2 preoperatively to 2982 G 365 cells/mm 2 3 months postoperatively in the PRK group; from 2995 G 325 cells/mm 2 to 2931 G 369 cells/mm 2 , respectively, in the thin-flap LASIK group.…”

Short-term and long-term effects of small incision lenticule extraction (SMILE) on corneal endothelial cells

“…When comparing the preoperative and postoperative ECD, no significant endothelial cell loss was shown at neither 1 day nor 1 year, and the changes were almost negligible. There are numerous studies in which influences of excimer laser-based refractive surgery on corneal endothelial cell loss were tested [15][16][17][18][19][20][21][22][23][24][25][26], and the annual rate of endothelial cell loss was within the range of physiological age-related endothelial cell loss [27,28]. Recently, endothelial cell loss in patients who underwent femtosecond-assisted refractive surgery was also reported.…”

Corneal endothelium after refractive surgery

“…The authors conclude that this cell loss rate is comparable to the normal age-related cell loss rate of 0.3% to 0.6% per year. 18,32 Other studies with shorter follow-ups verify that ECD loss is not affected by laser refractive surgery, but the studies differ as to the degree of alterations in cellular morphology. [49][50][51][52][53][54][55][56][57] In an ex vivo study, Kent et al 50 used human autopsy globes to study the effects of LASIK and PRK versus fellow-eye controls.…”

“…30 Contact lens use causes changes in endothelial cell morphology. 12,[31][32][33] This effect is especially severe with the use of older style, low gas-permeable contact lenses made of poly(methyl methacrylate) or hydroxyethyl methacrylate. Jones et al 12 report that people who wore contact lenses for longer than 25 years had the lowest preoperative ECD, the highest cellular pleomorphism, and the highest cellular polymegathism.…”

“…Laser in situ keratomileusis and photorefractive keratectomy (PRK) affect corneal thickness, keratocyte density, and anterior corneal nerves. 32,45,46 Using confocal microscopy, Erie et al 45 demonstrate that keratocyte density loss occurs in the flap and the anterior ablation zone very soon after surgery. Five years (but not 3 years) after refractive surgery, keratocyte density Four techniques are used to analyze endothelial cell images: compare relative cell size to standards, count cells within a predetermined fixed frame with the frame size significantly affecting accuracy, an algorithm using inputted cell corners, and an algorithm using inputted cell centers.…”