Abstract
Purpose: :
To determine whether ocular dominance should affect the visual benefit (VB) of correcting the high-order (HO) monochromatic aberrations.
Methods: :
We measured the high-contrast visual acuities (computer-generated Landolt-C optotypes) and 16-c/deg contrast sensitivity (computer-generated randomly oriented sine-wave gratings) before and after correcting the HO aberrations with the Imagine Eyes CRX1 device at a 1000-Td retinal illuminance on both eyes. In the first condition, the defocus term was subjectively adjusted by the observer to optimize the image quality of a 16-c/deg vertical sine-wave grating and the astigmatism term was corrected thanks to the adaptive optics (AO) system. The residual astigmatism was always lower than 0.1-D (0.08-µm). Under the second condition, the AO system was continuously run to measure and compensate the aberrations of the eye to a typical residual level lower than 0.1-µm. During both conditions, the subject viewed the stimulus through the optical device, including a 5.5-mm artificial pupil conjugated to the pupil plane, generated on a white calibrated LCD micro-display subtending 1.5° of visual angle. The subject’s head was stabilized with a bite bar. The subject’s pupil was not artificially dilated since the experiments were performed in dim surrounding illumination providing us subject’s pupil diameter higher than 5.5 mm. Ten subjects between the ages of 21 and 36 with normal vision and good ocular health were recruited for the study. Their ocular dominance was tested using the motor, red and plus lens tests.
Results: :
The average VB was 2.09 and 1.37 respectively in term of contrast sensitivity (CS) and visual acuity (VA). No statistically difference of VB between the two eyes was found whatever the ocular dominance test used. A significant lower VB (Wilcoxon test, VA p=0.010, CS p=0.013) was observed for the eye showing the better visual performance. The significant sphero-cylinder corrected visual performances differences between eyes were not correlated with differences of image quality metrics such as high-order aberrations RMS or MTF integrated between 5 and 15-c/deg indicating that the optics of the eye could not explain differences of performances. No significant difference of the full corrected visual performances was found between eyes.
Conclusions: :
One eye seems to be slightly blur adapted and consequently shows better sphero-cylinder corrected performances and lower benefit of correcting his HO aberrations.
Keywords: adaptation: blur • aberrations • contrast sensitivity