Differential changes in color and motion-onset visual evoked potentials from both eyes in early- and late-onset strabismic amblyopia.
OBJECTIVE
To examine changes in color- and motion-related visual function in patients with strabismic amblyopia.


METHODS
Motion-onset and color visual-evoked potentials (VEPs) were recorded in 16 adult patients with strabismic amblyopia which had an early onset, before 18 months of age, and 14 patients with amblyopia of later onset. The results are compared with those from 21 normal adults.


RESULTS
The peak times of motion-onset VEPs in the amblyopic eye were longer those than in the fellow eye in patients with both early- and late-onset strabismic amblyopia, but peak times in both amblyopic and fellow eyes were shorter than those in normal eyes. In patients with late- but not early-onset amblyopia, the peak times for color VEPs were significantly longer in amblyopic than in fellow and normal eyes.


CONCLUSIONS
The patterns of abnormality for motion-onset and color VEPs in patients with strabismic amblyopia are different, probably indicating differential changes in function in magno- and parvocellular pathways. These abnormalities affect both the amblyopic and fellow eyes and are different in patients with an onset of amblyopia before or after 18 months of age.
Strabismus and Paediatric Service, Moorfields Eye Hospital, London, United Kingdom.
Alison R
AR
Davis
John J
JJ
Sloper
Magella M
MM
Neveu
Chris R
CR
Hogg
Michael J
MJ
Morgan
Graham E
GE
Holder
D000293:Adolescent; D000328:Adult; D000550:Amblyopia / Q000503:physiopathology*; D003117:Color Vision Defects / Q000503:physiopathology*; D015350:Contrast Sensitivity / Q000502:physiology; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009039:Motion Perception / Q000502:physiology*; D013285:Strabismus / Q000503:physiopathology*