Abstract
Purpose: :
Evaluation of femtosecond LASIK flaps and excimer laser ablation depth with optical online coherence pachymetry in aspheric femtosecond LASIK in myopia and/or astigmatism
Methods: :
retrospective analysis of 76 myopic and/or astigmatic eyesmeasurement points: M1 (post femtosecondflap-creation / pre flaplift) M2 (post flaplift) M3 (pre ablation) M4 (post ablation) Δ 1 = M1-M2 (flapthickness) Δ 2 = M2-M3 (ablation depth)
Results: :
spherical äquivalent median : -3.3 , Range -0,5/-7.8, measured flapthicknessmedian 112µm, range +159/+59µm, predicted flapthickness 100µm,Δflapthicknessmedian 12µm, range +58.9/-41.5 µm, measured ablationdepth median 75µm,range +175/+14.5µm, Δablationdepth median 12µm, range -44µm/+3µm,ablationtime median 69s, range +168/+38s
Conclusions: :
Bubbles in the interface can increase the initial measurement of flapthickness.Corneal shrinking because of dehydration could decrease residual corneal flap thickness and increase calculated postoperative ablation depth. Outliners might be influenced by wrong measurement because of lateral decentration.
Keywords: refractive surgery: LASIK • refractive surgery • refractive surgery: other technologies