Purchase this article with an account.
T. Ogami, T. Samejima, T. Tokunaga, K. Miyata, T. Oshika; Influence of Pupil Diameter and Higher–Order Aberration on Contrast Sensitivity After Laser in situ Keratomileusis . Invest. Ophthalmol. Vis. Sci. 2005;46(13):2006.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: It has been reported that laser in situ keratomileusis (LASIK) significantly increases higher–order aberrations of the eye and decreases contrast sensitivity. But there have been no reports about the influence of pupil diameter and aberration on contrast sensitivity after LASIK. Methods: In 200 eyes of 100 patients (mean age 32.7 ± 8.4 years old), contrast sensitivity function and ocular aberrations were measured before and 1 month after LASIK. Higher–order aberrations of the eye were measured with a Hartmann–Shack wavefront aberrometer (Topcon KR–9000PW), and the root–mean–square (RMS) of the third– and fourth–order Zernike coefficients was used to represent coma– and spherical–like aberration, respectively. We measured contrast sensitivity using CSV–1000E (Vector Vision) and low contrast visual acuity using CSV–1000LanC10%. From the data of CSV–1000E, the area under the log contrast sensitivity function (AULCSF) was calculated. Analyses were done according to the photopic pupil diameter (<4 mm or >=4mm). Patient age and amount of correction were not different between these two groups. Results: In patients with photopic pupil diameter of 4 mm or larger, the changes in fourth–order RMS significantly correlated with the changes in AULCSF (r=–2.27, p=0.026) and 10% low contrast visual acuity (r=0.213, p=0.038), but third–order RMS did not correlate with either parameter. In patients with photopic pupil size smaller than 4 mm, there were significantly correlations between the changes in third–order RMS and the changes in AULCSF (r=–0.453, p<0.001) and 10% low contrast visual acuity (r=0.316, p=0.003), but fourth–order RMS showed no correlation. Conclusions: In cases with large pupil diameter, the increases in spherical aberration contribute to the reduction of contrast sensitivity, while in cases with small pupil diameter, coma aberration plays a major role in the deterioration of contrast sensitivity.
This PDF is available to Subscribers Only