Mesopic Functional Visual Acuity in Normal Subjects

Mesopic Functional Visual Acuity in Normal Subjects

To evaluate mesopic functional visual acuity (FVA) with a newly developed system in normal subjects and to compare the results with photopic FVA, sixty-eight healthy volunteers (24.03 ± 4.42 [mean ± standard deviation] years) were enrolled in this study. A commercially available FVA measurement system (AS-28; Kowa, Aichi, Japan) was modified to measure FVA under mesopic conditions as well as ph...

Optical quality of the eye in subjects with normal and excellent visual acuity.

PURPOSE To study the relationship between visual acuity (VA) and the eye's optical quality in subjects with normal and excellent spatial vision. VA ranged from decimal values of 1.0 (20/20) to 2.0 (20/10) when defocus and astigmatism were carefully corrected. METHODS In 60 eyes of young subjects, visual and optical performance with the natural pupil were measured. A forced-choice procedure wa...

Impaired mesopic visual acuity in eyes with early age-related macular degeneration.

PURPOSE To determine photopic and mesopic distance high-contrast visual acuity (HC-VA) and low-contrast visual acuity (LC-VA) in eyes with early age-related macular degeneration (AMD). METHODS Measurements were made in 22 subjects with early AMD and 28 healthy control subjects. Inclusion criteria included a photopic HC-VA of 20/25 or better. Distance VA was measured using HC (96%) and LC (10%...

Dynamic visual acuity of normal subjects during vertical optotype and head motion.

PURPOSE To characterize the effect of passive vertical head motion on dynamic visual acuity of young, normally sighted subjects wearing telescopic spectacles, and to relate this to the velocity of images on the retina. METHODS Static visual acuity was measured without motion. Dynamic visual acuity was measured during vertical, sinusoidal motion of either optotypes or of a servo-driven rotatin...

Predicting lamp spectrum effects at mesopic levels. Part 2: Preferred appearance and visual acuity