Abstract
Purpose :
To assess the effects of astigmatism on contrast sensitivity (CS) assessed using multiple measurement charts.
Methods :
Twenty normal volunteers (27.8 ± 7.1 [mean ± SD] years) with spherical equivalent refraction between 0 and –2.00 diopters (D) and refractive astigmatism up to 1.00 Dwere recruited. After fully correcting the refractive error by spectacles, against-the-rule (ATR) astigmatism of +1.00, +2.00 and +3.00D was intentionally produced in both eyes, and then binocular CS was measured. The same measurements were repeated with with-the-rule (WTR) andoblique (OBL) astigmatism of +3.00D in both eyes. Foreye We tested with three CS measurement charts: sine-wave grating CS with the CSV-1000E (Vector Vision Co, Greenville, Ohio, USA), low contrast visual acuity with the CSV-1000LanC10%, and letter-CS with the CSV-1000LV-C.From the data obtained with the CSV-1000E, the area under the log CS function (AULCSF) was calculated. The order of cylindrical induction with different powers and axes was randomly determined.
Results :
Induction of ATR astigmatism from +1.00 to +3.00 D significantly deteriorated AULCSF, low contrast visual acuity, and letter-CS depending on the amount of added astigmatic powers (p < 0.0001, Spearman correlation test).When compared among the axes of +3.00 D astigmatic defocus, AULCSF with OBL astigmatism was significantly worse than that with WTR and ATR (p < 0.05, Fisher’s PLSD). In contrast, there were no significant differences in low contrast visual acuity and letter-CS among astigmatic axes.
Conclusions :
Binocular astigmatic defocus deteriorated CS depending on the amount of astigmatic power which was most sensitively detected with the sine-wave grating CS chart. The influence of OBL astigmatism on AULCSF was larger than that of WTR and ATR.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.