J Korean Ophthalmol Soc.  2012 Mar;53(3):365-371.

Clinical Outcomes of Advanced Surface Ablation with Smoothing in High Myopia

• Ahn KS
• Lee SW
• Lee GH
• Choi BJ

Abstract

PURPOSE
To investigate the results of Advanced Surface Ablation (ASA) coupled with "smoothing" to smooth the ablation surface after covering masking fluid.
METHODS
ASA was performed in 61 eyes with ablation depth of more than 75 microm. The mean refractive error was -5.88 +/- 1.27 D and mean ablation depth was 102.93 +/- 12.06 microm. Smoothing was performed in all patients (mean depth 16.79 +/- 2.43 microm, mean diameter 8.77 +/- 0.16 mm). Customized Aspheric Transition zone (CATz) was used in the laser algorithm.
RESULTS
The mean refractive error was -0.29 +/- 0.41 D at postoperative 6 months and 97% of patients had an UCVA of 1.0 or better at postoperative 6 months. There was no statistically significant difference in magnitude of high-order aberrations at postoperative 6 months. The magnitude of total spherical aberrations increase was 0.084 microm at postoperative 6 months (p<0.05, paired t-test). The cornea was maintained clear in the majority of eyes.
CONCLUSIONS
Excellent results were obtained by ASA coupled with "smoothing" in high myopia patients with an ablation depth greater than 75 microm.

Keyword

Advanced surface ablation (ASA); Customized Aspheric Transition zone (CATz); High myopia; Smoothing

MeSH Terms

Cornea
Eye
Humans
Masks
Myopia
Refractive Errors

Figure

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  Figure 1 Distribution of uncorrected visual acuity after advanced surface ablation with smoothing over time.

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  Figure 2 Mean spherical equivalent following advanced surface ablation with smoothing at different follow-up periods.

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  Figure 3 Distribution of eyes in a given range of emmetropia after advanced surface ablation with smoothing.

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  Figure 4 Changes in total high order aberration and total spherical aberration during postoperative 6 months. *p < 0.05 (paired t-test) compared with preoperative value.

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  Figure 5 Patient's satisfaction after advanced surface ablation with smoothing.

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