Motion perimetry in anisometropic amblyopia: elevated size thresholds extend into the midperiphery.
OBJECTIVE
Our purpose was to determine whether motion detection abnormalities in patients with anisometropic amblyopia exist and to determine the extent of these abnormalities in the central and midperipheral visual field.


METHODS
We used of motion perimetry to evaluated 10 anisometropic subjects with no manifest strabismus. Each of 44 locations in the visual field corresponding to the test sites of the Humphrey 24-2 program was tested with circular patches of motion (random dot cinematograms) displayed on a computer screen. Stimulus patch size was reduced in a 2/1 staircase manner to determine the smallest patch of motion detectable at each test location (threshold). Data from 15 age-matched normal subjects were used as controls.


RESULTS
Vision in the amblyopic eye ranged from 20/25 to count fingers. The overall mean size threshold for amblyopic eyes was elevated (61% +/- 73%) compared with fellow eyes and age-matched normal eyes (p < 0.03) (i.e., the moving patch of dots in the field had to be larger for it to be detected when viewing with the amblyopic eye). The increase in size threshold was consistent across the visual field and was not greater for central locations.


CONCLUSIONS
The amblyopia caused by anisometropia is associated with an abnormality in motion detection that extends into the midperiphery of the visual field.
Donahue
S P
SP
Department of Ophthalmology and Visual Sciences, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
Wall
M
M
Stanek
K E
KE
D000550:Amblyopia / Q000209:etiology / Q000503:physiopathology*; D015858:Anisometropia / Q000503:physiopathology*; D005584:Fovea Centralis / Q000502:physiology; D006801:Humans; D009039:Motion Perception / Q000502:physiology*; D012016:Reference Values; D012030:Refractive Errors / Q000150:complications; D012684:Sensory Thresholds; D014792:Visual Acuity; D058609:Visual Field Tests; D014794:Visual Fields