The effects of unilateral lid closure and artificial esotropia on the development of visual acuity were studied in visually immature rhesus monkeys (Macaca mulatta). Irreversible amblyopia occurred in all animals whose lids were sutured between birth and nine weeks of age. Lid closure at the age of 12 weeks did not produce amblyopia. During the age of susceptibility only brief periods of occlus...

Humans with naturally occurring amblyopia show deficits thought to involve mechanisms downstream of V1. These include excessive crowding, abnormal global image processing, spatial sampling and symmetry detection and undercounting. Several recent studies suggest that humans with naturally occurring amblyopia show deficits in global image segregation. The current experiments were designed to stud...

Amblyopia is reduction of vision with the proper optical correction either in one or both eyes.. The diagnosis of Amblyopia requires both the demonstration of visual acuity loss and the absence of an organic cause. A visual defect screening program was conducted on children aged 3-14 years of Bope-Poddala health unit area of the city of Galle Sri Lanka. Children aged 5-14 years were examined at...

We have compared the effects on visual acuity and binocular functions of grating stimulation (CAM therapy) and full-time occlusion in 38 4-year-old, previously untreated amblyopic children. The patients were divided into subgroups with regard to amblyopia type and fixation pattern. We found that grating stimulation was slightly better than occlusion in improving visual acuity of anisometropic a...

At birth a baby’s vision is very immature, with an acuity of around 3/601,2. Visual experience in infancy and childhood has a major influence on the development of the visual pathways, particularly the visual cortex3,4. During the critical periods of visual development visual acuity develops as do other modalities such as contrast sensitivity, colour, pattern and motion perception, and binocula...

The effects of unilateral lid closure and artificial esotropia on the development of visual acuity were studied in visually immature rhesus monkeys (Macaca mulatta). Irreversible amblyopia occurred in all animals whose lids were sutured between birth and nine weeks of age. Lid closure at the age of 12 weeks did not produce amblyopia. During the age of susceptibility only brief periods of occlus...

AIMS Clinically, picture acuity tests are thought to overestimate visual acuity (VA) compared with letter tests, but this has not been systematically investigated in children with amblyopia. This study compared VA measurements with the LogMAR Crowded Kay Picture test to the LogMAR Crowded Keeler Letter acuity test in a group of young children with amblyopia. METHODS 58 children (34 male) with...

We investigated the patterns of two-dimensional spatial distortions in human amblyopia, using three different psychophysical mapping procedures. Strabismic and strabismic-anisometropic amblyopes showed consistent distortions, consisting in enlargement, shrinkage, or torsion of portions of the tested visual field. Purely anisometropic amblyopes and strabismics with alternating fixation showed in...

Aims: Clinically, picture acuity tests are thought to overestimate visual acuity (VA) compared with letter tests, but this has not been systematically investigated in children with amblyopia. This study compared VA measurements with the LogMAR Crowded Kay Picture test to the LogMAR Crowded Keeler Letter acuity test in a group of young children with amblyopia. Methods: 58 children (34 male) with...