a-wave amplitude of ERG waveform scotopic A wave amplitude of ERG waveform 2021-05-06T18:45:14Z CMO:0003706 Electroretinographic scotopic measurement targets rod-pathway function made from the dark-adapted eye. The a-wave is the first large negative component of the electrical wave generated by the retina in response to light. The amplitude of the a-wave is measured from the baseline to the negative trough of the a-wave. If the stimulus light is weak, no scotopic A wave can be measured. PMID:27384999 VT:0004021 clinical_measurement_ontology slaulede