ZHANG Yun-hai, LIAO Wen-he, SHEN Jian-xin. Blend zone model for excimer laser refractive surgery[J]. Editorial Office of Optics and Precision Engineering, 2004,(4): 406-410
ZHANG Yun-hai, LIAO Wen-he, SHEN Jian-xin. Blend zone model for excimer laser refractive surgery[J]. Editorial Office of Optics and Precision Engineering, 2004,(4): 406-410DOI:
Blend zone model for excimer laser refractive surgery
A blend zone model for excimer laser refractive surgery is presented. Firstly
a blend function is designed. Then
an expand ablation depth in the blend zone is constructed using the ablation depth on the edge of the optical zone. Finally
the model is developed by multiplying the blend function and the expand ablation depth. The simulation of the model on computer and results of clinical practice have been studied. Sixteen eyes with myopic astigmatism underwent LASIK using the blend zone model. One day postoperatively
mean uncorrected visual acuity was 1.06?0.24 compared to 0.09?0.04 preoperatively. One month after surgery
mean uncorrected visual acuity was 1.42?0.36. All eyes reached uncorrected visual acuity of 1.0 or better. The computer simulation and especially LASIK results show that the model gradually smoothes out the connection of the optical zone and untreated zone. The model has two parameters that make it very useful in adjusting the diameter of the optical zone and changing the width of the blend zone. The ablation depth in the optical zone does not increase when the width of the blend zone is changed. The model not only can be applied to the correction of refractive errors such as myopia and astigmatism
but also can be used in wavefront guided laser refractive surgery. Visual acuity after excimer laser refractive surgery has been remarkably improved using this model.
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references
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