Abstract
Purpose :
People with advanced age-related macular degeneration (AMD) rely on their peripheral vision for many daily tasks where foveal vision is normally used. Sometimes magnification is used, but that comes at the cost of reduced visual field. Peripheral optical errors differ from central errors and can depend on factors such as the presence of an intraocular lens. In the current study, we evaluated the peripheral vision with naturally occurring average errors and a condition of larger errors on a group of AMD subjects as well as a control group.
Methods :
High contrast grating resolution acuity and contrast sensitivity were evaluated in 11 control subjects with no ocular disorders and 9 AMD subjects. All measurements were performed monocularly at 20° nasal visual field. We tested 2 different optical conditions with an adaptive optics vision simulator designed for peripheral vision evaluations: 1) Simulated average phakic optical errors in 20° nasal visual field (-0.60 D spherical equivalent, -1.00 D cylinder with axis 90° and 0.09 µm horizontal coma for a 4 mm pupil); 2) larger errors in 20° nasal visual field (-1.20 D spherical equivalent, -2.90 D cylinder with axis 90° and 0.09 µm horizontal coma for a 4 mm pupil). The individual errors of the subjects were corrected. Contrast sensitivity (CS) was evaluated at 1 cycle/degree in the control subjects. For AMD subjects, only 6 subjects were able to perform the CS measurements and the CS was evaluated at a spatial frequency logarithmically midway between 1 cycle/degree and the resolution acuity cut-off.
Results :
Reduced peripheral optical errors improved high contrast resolution significantly for both groups. The mean improvement was 0.08 and 0.16 logMAR in control and AMD, respectively. The CS was also significantly improved, with gains in control and AMD subjects of 0.29 and 0.39 logCS.
Conclusions :
The average phakic peripheral optical error condition provides significantly better peripheral vision, with larger improvements in patients with AMD than in healthy eyes. Therefore, patients with AMD are likely to benefit more than healthy by controlling the peripheral optical errors, it may for example reduce the need of magnification.
This is a 2021 ARVO Annual Meeting abstract.