The pattern visual evoked potential and pattern electroretinogram in drusen-associated optic neuropathy
G. B. Scholl, H. S. Song, D. E. Winkler and S. H. Wray
Department of Neurology, Massachusetts General Hospital, Boston 02114.
Sixteen patients (29 eyes) with optic disc drusen were studied
prospectively for clinical and electrophysiologic evidence of impaired
optic nerve conduction. Abnormalities were detected in the following areas:
visual acuity, eight (28%) of 29 eyes; kinetic visual field, 22 (76%) of 29
eyes; results of Farnsworth-Munsell 100-Hue test, 12 (41%) of 29 eyes; and
flash visual evoked potential, 13 (54%) of 24 eyes. Simultaneous pattern
visual evoked potentials and results of pattern electroretinograms were
recorded. The P100 latency of the pattern visual evoked potential was
prolonged in 41% of eyes. The P50 and N95 components of the pattern
electroretinogram were also analyzed. The P50 amplitude was reduced in only
four (17%) of 24 eyes. The most common abnormality was a reduction in
amplitude or the absence of the N95 component in 19 (79%) of 24 eyes,
reflecting ganglion cell dysfunction. The data support mounting evidence
that the P50 and N95 components of the pattern electroretinogram have
different retinal origins.
