Abstract
Methods
The electroretinogram (ERG) waves were recorded in 52 eyes of 26 normal subjects with UTAS E-3000® (LKC Technologies Inc., Gaithersberg, MD, USA). Photopic cone response was obtained for analysis from a white flash with white background illumination (group 1) and a red flash with blue background illumination (group 2), after stimulations ranging from 0.007674 cd.s/m2 (-25dB) to 7.736 cd.s/m2 (5dB) with a 5dB interval.
Results
PhNRs were observed in all 52 eyes in group 1 stimulated with the white flash at 0.9933 cd.s/m2 (-4dB). PhNRs were also observed in all 52 eyes in group 2 at 2.4297 cd.s/m2 (0dB) after stimulation with the red flash. There was correlation between the amplitudes of PhNR and intensity of stimuli (p <0.001). Implicit times of PhNR were correlated with age in both groups, but amplitudes decreased with age in group 1.
References
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Table 1.
Intensity of stimulation | 0.9933 cd.s/m2 (-4dB) | 2.4297 cd.s/m2 (0dB) | 7.3536 cd.s/m2 (5dB) | p-value |
---|---|---|---|---|
Group 1 (White stimulus) | ||||
Amplitude (uV) | 18.18±8.32 | 28.29±10.87 | 31.34±9.15 | <0.001* |
Implicit time (ms) | 43.23±1.94 | 42.83±1.80 | 43.12±1.49 | 0.482* |
Group 2 (Red stimulus) | ||||
Amplitude (uV) | 4.50±2.93 | 16.98±7.91 | <0.001† | |
Implicit time (ms) | 47.96±3.75 | 46.69±3.47 | 0.076† |