Functional magnetic resonance imaging of binocular interactions in visual cortex in strabismus.
OBJECTIVE
To observe changes in primary visual cortical activation associated with perceptual suppression in individuals with strabismus, using functional magnetic resonance imaging (fMRI).


METHODS
In Phase 1, pilot data were collected from 1 control and 8 strabismic participants, including 5 with amblyopia. In Phase 2, results were collected from 7 participants with strabismus (2 recalled and 5 new), including 2 with amblyopia. fMRI compared primary visual cortex activation in two conditions: visual stimuli presented to both eyes, to evoke perceptual suppression of one eye in individuals with strabismus, and visual stimulation presented only to one eye.


RESULTS
Visual cortical activity modulations positively correlated with perceptual suppression were seen in 3 of 5 non-amblyopic Phase 2 study participants, but not in amblyopic subjects.


CONCLUSIONS
Cortical activity modulations correlated with modulation of strabismic suppression are detectable in non-amblyopic individuals using fMRI, suggesting a neural basis for strabismic suppression in primary visual cortex.
Department of Radiology and Vision Center, Children’s Hospital Los Angeles, 4650 Sunset Blvd., Los Angeles, CA 90027, USA.
Vincent J
VJ
Chen
Kristina
K
Tarczy-Hornoch
D000293:Adolescent; D000328:Adult; D002648:Child; D003867:Depth Perception / Q000502:physiology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010468:Perceptual Disorders / Q000503:physiopathology*; D013285:Strabismus / Q000503:physiopathology*; D015348:Vision, Binocular / Q000502:physiology*; D014792:Visual Acuity / Q000502:physiology; D014793:Visual Cortex / Q000503:physiopathology*; D055815:Young Adult