Effect of Pupil Size on Corneal Aberrations Before and After Standard Laser In Situ Keratomileusis, Custom Laser In Situ Keratomileusis, and Corneal Refractive Therapy

Abstract

The 3 techniques increase the wavefront aberrations of the cornea and change the relative contribution of coma-like and spherical-like aberrations. For a large aperture (> 5 mm), corneal refractive therapy induces more spherical-like aberrations than standard and custom LASIK. However, no clinically or statistically significant differences existed for narrower apertures. Standard and custom LASIK did not display statistically significant differences regarding higher-order aberrations.

Recovery Evaluation of Induced Changes in Higher Order Aberrations From the Anterior Surface of the Cornea for Different Pupil Sizes After Cessation of Corneal Refractive Therapy

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] Our results are in agreement with those obtained in the previous studies, showing an important reduction of spherical equivalent refraction (from 21.99 ± 1.02 D at baseline to 20.28 ± 0.46 D at 1 month and to 20.23 ± 0.58 D at 12 months after the start of the treatment) and no changes in visual acuity values. *Statistically significant differences between baseline and after the beginning of the treatment.…”

“…[17][18][19] The results of these 3 studies agree that both techniques increase the corneal HOAs and that CRT induces more spherical-like aberrations. This is an important disadvantage for CRT over corneal refractive surgeries.…”

“…These results are supported by the various studies conducted by others authors. [7][8][9][10][11][12][13][14][15][16][17][18][19] Hiraoka et al [10][11][12][14][15][16] showed that the RMS of coma-like and spherical-like aberrations increased significantly after treatment. In addition, these authors reported that the increase in these RMS values had a positive correlation with the amount of myopic correction.…”

“…The success of CRT has been accompanied by the need for addressing the factors that affect the corneal response to treatment. Recent research has examined the use of CRT in humans, evaluating its effects on corneal topography, visual acuity, contrast sensitivity, and optical quality of the eye (ocular aberrations) [7][8][9][10][11][12][13][14][15][16][17][18][19] and assessing intraocular straylight. 20 It has been well documented in these previous studies that CRT causes a decrease in the optical quality of the cornea and it could provoke a decrease in visual quality.…”

Femtosecond laser versus mechanical microkeratome laser in situ keratomileusis for myopia: Metaanalysis of randomized controlled trials

“…Future metaanalyses with more consistent data should compare aberrations for larger optical zones because LASIKinduced aberrations increase exponentially as the optical zone enlarges. 37 Complications as a result of LASIK remain a troubling side effect for surgeons and patients. We found a higher tendency toward postoperative DLK in the femtosecond laser group than in the mechanical microkeratome group (PZ.01).…”