PURPOSE To compare visual acuity (VA) assessed in healthy eyes and eyes with diabetic retinopathy (DR) using three different logMAR charts: the Sloan letter European-wide chart, the tumbling E chart, and the Landolt C chart. METHODS Measurements on one eye of 40 volunteers (aged 29 ± 4 years) without visual impairment and 31 DR patients (aged 70 ± 9 years) with mild/moderate visual impairment...

Measurement of visual acuity remains the most frequently used technique for the assessment of vision in both adults and children. Visual acuity is usually measured clinically in adults using a Snellen chart. However. this technique demands a level of cognition and literacy which is beyond the majority of young children. The measurement of visual acuity in preschool children presents an addition...

OBJECTIVE We sought to ascertain quality-of-life measures and utility values associated with visual acuity in type 2 diabetes. RESEARCH DESIGN AND METHODS The Medical Outcome Study Short Form with 36 items (SF-36) was administered to 4,051 individuals with type 2 diabetes who were enrolled in the Lipids in Diabetes Study, and their best attainable vision was determined using an Early Treatmen...

Previously reported superior visual acuity (VA) in autism spectrum conditions (ASC) may have resulted from methodological settings used (Ashwin, Ashwin, Rhydderch, Howells, & Baron-Cohen, 2009). The current study re-tested whether participants with (N=20) and without (N=20) ASC differ on psychophysical measures of VA. Participants' vision was corrected before acuity measurement, minimising refr...

AIM To assess the repeatability of Eger macular stressometer (EMS) measures of photostress recovery and determine their association with other measures of visual function. METHODS EMS photostress recovery time was measured in 90 patients with bilateral exudative age related macular degeneration (AMD), 19 with bilateral atrophic AMD and 47 with both forms of the condition (mean age 79 (SD 13) ...

The drawbacks of conventional letters in visual acuity measurements have been long acknowledged, including the nonuniform discriminability across the letter set and high test–retest variability. Apart from the introduction of the ETDRS chart, surprisingly few alterations have been made to the standard visual acuity test in the last 60 years. Although the Landolt C target, with equal discriminab...

Visual acuity is d&ned as the reciprocal of the visual angle, in minutes. subtended by a just resolvable stimulus. This critical dimension can be the gap in a Landolt C, the spatiat period of a grating or the offset of a vernier. etc. Acuity declines progressively from the fovea out to the periphery of the retina. It is down to half its maximum value at an eccentricity of only 30 min according ...

A compact electronic device which enables the user to determine for himself whether his visual acuity reaches a chosen standard has been constructed at a cost of 25 pounds. The instrument provides a test which requires the observer to respond to the orientation of a sequence of red Landolt-Cs and which takes under five minutes to complete. 'Crowding' effects associated with conventional letter ...