Nicolas Chateau, Arnaud Blanchard, and Dominique Baude, "Influence of myopia and aging on the optimal spherical aberration of soft contact lenses," J. Opt. Soc. Am. A 15, 2589-2596 (1998)
Soft contact lenses with different levels of third-order spherical aberration were tested in two samples of subjects aged between 20 and 45 years: 18 emmetropes and 19 myopes. Contrast sensitivity was measured at 12 cycles/degree to determine the optimal lens spherical aberration required by each individual. The optimal third-order coefficient was found to be negative on average in both refractive error groups. Myopic subjects required contact lenses with more negative spherical aberration than did emmetropes. The optimal aberration was also found to become increasingly negative with aging. The rate of this age-related change was faster in the myopic group. In comparison with aberration-free soft contact lenses, an improvement in contrast detection threshold of more than 25% was observed with optimal spherical aberration in half of the myopic subjects.
Petros Papadogiannis, Dmitry Romashchenko, Shrilekha Vedhakrishnan, Britta Persson, Anna Lindskoog Pettersson, Susana Marcos, and Linda Lundström J. Opt. Soc. Am. A 39(6) B39-B49 (2022)
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
Characteristic Values of the Clinical Protocol Used in Sample Size and Power Analysis Calculationsa
Type I error probability
Type II error probability
Minimum detectable difference
log unit
Estimated standard deviation
log unit
Estimated correlation between two responses from a single subject
Ref. 28. The risk levels and the minimum detectable difference were chosen by the authors; the standard deviation and the intrasubject correlation coefficient were estimated from the data of de Brabander et al.10
Table 2
Parameters and Test Conditions for CS Measurements
After three correct answers or one incorrect answer
Change in step value
50% of former value after four inversions
Minimal step
0.04 log unit
Maximum number of presentations
65
Cycles per degree.
Table 3
Spherical Aberration Coefficients A and Paraxial Powers of the Prototype SCL’sa
-0.27
-0.23
-0.19
-0.14
-0.074
0.0
0.074
0.14
0.19
*
*
*
*
*
*
*
*
*
*
*
*
*
*
The lenses actually tested in the study are represented by asterisks. Lenses with plano–paraxial power were experimented in emmetropic subjects; lenses with in myopes.
Table 4
Descriptive Statistics of the Results in Myopic and Emmetropic Samples
Characteristic Values of the Clinical Protocol Used in Sample Size and Power Analysis Calculationsa
Type I error probability
Type II error probability
Minimum detectable difference
log unit
Estimated standard deviation
log unit
Estimated correlation between two responses from a single subject
Ref. 28. The risk levels and the minimum detectable difference were chosen by the authors; the standard deviation and the intrasubject correlation coefficient were estimated from the data of de Brabander et al.10
Table 2
Parameters and Test Conditions for CS Measurements
After three correct answers or one incorrect answer
Change in step value
50% of former value after four inversions
Minimal step
0.04 log unit
Maximum number of presentations
65
Cycles per degree.
Table 3
Spherical Aberration Coefficients A and Paraxial Powers of the Prototype SCL’sa
-0.27
-0.23
-0.19
-0.14
-0.074
0.0
0.074
0.14
0.19
*
*
*
*
*
*
*
*
*
*
*
*
*
*
The lenses actually tested in the study are represented by asterisks. Lenses with plano–paraxial power were experimented in emmetropic subjects; lenses with in myopes.
Table 4
Descriptive Statistics of the Results in Myopic and Emmetropic Samples