Korean J Ophthalmol.  2007 Sep;21(3):131-136. 10.3341/kjo.2007.21.3.131.

The Changes of Posterior Corneal Surface and High-Order Aberrations after Refractive Surgery in Moderate Myopia

• Lee MJ
• Lee SM
• Lee HJ
• Wee WR
• Lee JH
• Kim MK

• KMID: 1099026
• DOI: http://doi.org/10.3341/kjo.2007.21.3.131

Abstract

PURPOSE: To compare forward shift of posterior corneal surface and higher-order aberration (HOA) changes after LASIK, LASEK, and wavefront-guided LASEK surgery in moderate myopia METHODS: One hundred eighty four eyes undergoing LASIK, LASEK and wavefront-guided LASEK with VISX STAR S4 were included in this study. The posterior corneal elevation was measured with Orbscan before, 2 and 4 months after surgery. Changes of the elevation were assessed using the difference map generated from preoperative and postoperative elevation maps. The values of higher-order aberrations were evaluated preoperatively and 2 months postoperatively with Wavefront aberrometer. RESULTS: The posterior corneal surface displayed forward shift of 27.2+/-11.45 micrometer, 24.3+/-9.76 micrometer in LASIK group, 23.4+/-10.5 micrometer, 23.6+/-10.55 micrometer in LASEK group, 24.0+/-14.95 micrometer, 28.4+/-14.72 micrometer in wavefront-guided LASEK group at 2 months and 4 months, respectively. There were no statistically significant differences among those three groups, and between 2 and 4 months. The root mean score (RMS) of HOA was increased after LASIK and LASEK (p=0.000, p=0.000, respectively). The mean change of HOA-RMS was significantly smaller in wavefront-guided LASEK than LASIK or LASEK (p=0.000, p=0.000, respectively, Bonferroni-corrected). CONCLUSIONS: The changes of posterior corneal surface forward shift showed no difference among LASIK, LASEK and wavefront-guided LASEK in moderate myopia. HOAs were significantly increased after LASIK and LASEK. The changes of HOAs were significant smaller in wavefront-guided LASEK than LASIK or LASEK.

Keyword

Aberration; LASEK; LASIK; Posterior corneal surface; Wavefront-guided ablation

MeSH Terms

Adult
*Corneal Topography
Humans
Myopia/diagnosis/*physiopathology/*surgery
Postoperative Period
*Refractive Surgical Procedures
Severity of Illness Index

Figure

• 

  Fig. 1 The changes of posterior elevation measured using difference map showed no statistically significant difference between LASIK and LASEK, between LASEK and Wavefront-guided LASEK at 2 and 4 month postoperatively (p>0.05).

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