New test hemisphere for evaluation and development of ablation profiles

PURPOSE: To develop and apply a new evaluation device for testing excimer laser ablation that allows a three-dimensional test of the characteristics of the imparted ablation. METHODS: A specially designed PMMA hemisphere with a 43.00-D curvature was developed, and results obtained with different algorithms and profiles of curvature with the Nidek EC-5000 excimer laser were evaluated. Topography, OPD-scan, wavefront, and keratoscopy were performed before and after ablation. RESULTS: The test hemisphere proved to be a reliable tool, allowing repeatable ablation results, precise calibration results, as well as experimental evaluation and comparison of new profiles. CONCLUSION: This new PMMA hemisphere can be used to improve the understanding of commonly used ablation algorithms and profiles, as well as in the daily safety routine and the experimental development and evaluation of advanced treatment solutions in excimer laser refractive surgery.