Effects of corneal irregular astigmatism on visual acuity after conventional and femtosecond laser-assisted Descemet's stripping automated endothelial keratoplasty

Jpn J Ophthalmol. 2015 Jul;59(4):216-22. doi: 10.1007/s10384-015-0388-y. Epub 2015 Jun 2.

Abstract

Purpose: To compare short-term outcomes of Descemet's stripping automated endothelial keratoplasty (DSAEK) using a graft prepared with either a femtosecond laser or a microkeratome.

Methods: Thirty-eight patients underwent DSAEK with grafts prepared with either a femtosecond laser (f-DSAEK; 21 eyes) or a microkeratome (m-DSAEK; 17 eyes). Visual acuity, endothelial cell density, regular astigmatism and irregular astigmatism were compared between the two groups preoperatively and at 1, 3, and 6 months post-operatively. Fourier analysis was conducted to calculate astigmatism of the anterior and posterior surfaces, and total cornea, using anterior segment optical coherence tomography (AS-OCT).

Results: Visual acuity (logMAR) improved from 1.20 ± 0.60 to 0.43 ± 0.25 after m-DSAEK (P < 0.001) and from 1.20 ± 0.57 to 0.77 ± 0.33 after f-DSAEK (P = 0.0028) at 6 months following DSAEK. Visual acuity after m-DSAEK was significantly better than after f-DSAEK at 1, 3, and 6 months (P < 0.05). AS-OCT corneal images revealed greater irregularities on the posterior surfaces of f-DSAEK grafts compared to m-DSAEK grafts. Irregular astigmatism of the total cornea and the posterior surface was significantly larger after f-DSAEK than after m-DSAEK, although there was no significant difference in irregular astigmatism of the anterior surface at 6 months. Postoperative visual acuity was significantly correlated with the postoperative irregular astigmatism of the total cornea (r = 0.6657 and P < 0.001) and the anterior (r = 0.416, P = 0.016) and posterior surfaces (r = 0.7046, P < 0.001).

Conclusions: Visual outcomes after f-DSAEK were poor compared to conventional m-DSAEK due to an increase in irregular astigmatism caused by posterior surface irregularities.

Publication types

  • Comparative Study

MeSH terms

  • Aged
  • Aged, 80 and over
  • Astigmatism / physiopathology*
  • Cell Count
  • Cornea / physiopathology*
  • Corneal Diseases / surgery
  • Corneal Endothelial Cell Loss / pathology
  • Corneal Topography
  • Descemet Stripping Endothelial Keratoplasty*
  • Endothelium, Corneal / pathology
  • Female
  • Fourier Analysis
  • Humans
  • Male
  • Middle Aged
  • Tomography, Optical Coherence
  • Treatment Outcome
  • Visual Acuity / physiology*