Article

An objective VER assessment of visual acuity compared with subjective measures.

Department of Optometry, Bradford University, United Kingdom.
American journal of optometry and physiological optics 01/1989; 65(12):957-61. pp.957-61
Source: PubMed

ABSTRACT Visual acuity was estimated by making amplitude measurements of the transient visually evoked response (VER) wave to pattern reversal using check sizes of 5.5, 7.5, 8.5, and 9.5 min arc. As in previous studies the 5.5 min arc check produced a response which reflected the visual acuity of the high acuity subjects, but often failed to produce a VER wave at the low acuity end. The proposal is made that where the 5.5 min arc check produces an acceptable wave (amplitude greater than 1.5 microV) then the regression line for the 5.5 check can be used to predict visual acuity. Where the VER amplitude is below 1.5 microV for this small check size then a second recording must be made using the 9.5 min arc check and the visual acuity predicted from the 9.5 check regression line.

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Keywords

5.5 min arc check
 
9.5 check regression line
 
9.5 min arc check
 
acceptable wave
 
acuity subjects
 
check sizes
 
low acuity end
 
pattern reversal
 
previous studies
 
small check size
 
VER
 
VER amplitude
 
VER wave
 
visual acuity
 

T C Jenkins