The predictability of corneal flap thickness and tissue laser ablation in laser in situ keratomileusis
Section snippets
Materials and methods
The study protocol was reviewed and approved by the institutional review board at the University of Colorado Health Sciences Center. A total of 60 patients (102 eyes) were enrolled in the investigation. All procedures were performed by the same surgeon (LS) using the same laser. Exclusion criteria included previous corneal surgery, history of corneal dystrophy, previous refractive surgery, corneal scarring from corneal infection or trauma, or a history of glaucoma.
Preoperative measurements
Results
Data from 102 eyes of 60 patients who had undergone LASIK for myopia were available for the initial analysis. Five eyes (four patients) were excluded from all analyses because of missing data. Of the remaining 97 eyes, seven eyes had missing data from some of the analyses. Each analysis performed had a minimum sample of 92 eyes of 55 patients.
Discussion
This study examines both the relationship between predicted corneal flap thickness and actual corneal flap thickness and between predicted tissue ablation and actual tissue ablation. Subtraction pachymetry was used to measure corneal flap thickness and the amount of tissue ablated. Accurate predictability of the refractive and visual results of LASIK requires an accurate laser algorithm. As such, predicted corneal flap thickness and predicted tissue ablation are important entities.
The ability
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