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Abstract
Purpose
To present prospective clinical results of laser-assisted in situ keratomileusis (LASIK) using a solid-state laser system for the correction of mild to moderate myopia with or without astigmatism.
Methods
Thirty-eight eyes underwent LASIK using a 213 nm solid-state laser (Pulzar Z1TM, CustomVisTM, Australia). Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), refractive errors, higher order aberrations (HOA) and contrast sensitivity were evaluated preoperatively and postoperatively.
Results
The preoperative and postoperative mean spherical and cylindrical refractive errors were −3.27±0.85D, +1.04±0.69D, −0.36±0.7D and +0.14±0.2D, respectively. UCVA over 20/25 was obtained in 27 eyes (93%). A result within 1.00D of the desired correction was achieved in 90% of the eyes. There were no decreases in BCVA within the study group. The preoperative and postoperative root-mean-square of HOA at 3 months were 0.196±0.092 μ m and 0.326±0.107 μ m respectively. The preoperative and postoperative contrast sensitivity values were similar.
References
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Figure 1.
Uncorrected visual acuity (UCVA) after surgery. UCVAover 20/20 was presented in 63% at postoperative 1 week and 74% at postoperative 3 and 6 months. Uncorrected visual acuity over 20/25 was presented in about 90 % after postoperative 1 week.
Figure 2.
Best corrected visual acuity (BCVA). BCVA over 20/25 was presented in all patients after post-operative 1 week. And there was no loss in BCVA compared with preoperative visual acuity.
Figure 3.
Changes of spherical error. Changes of post-operative refractive error were minimal after post-operative 1 week.
Figure 5.
Changes of contrast sensitivity. (A) Under photopic conditions although the chart shows slight decrease of postoperative contrast sensitivity values in all cpds, there was no significance. (B) There was no significant difference in preoperative and postoperative contrast sensitivity values under mesopic conditions.
Table 1.
Patient demographics and refractive data
| M: F | 10: 9 |
|---|---|
| Age (year) | 30.0±5.20 (23∼42) |
| Mean Spherical error (Diopter) | −3.27±0.85 (−1.5∼-4.75) |
| Mean Cylindrical error (Diopter) | 1.04±0.69 (0∼1.75) |
| Mean corneal thickness (um) | 533.36±34.30 (447∼570) |
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