Evoked potentials in Huntington's disease. A comparative and longitudinal study.

Pattern-reversal visual (PRVEPs), brain-stem auditory (BAEPs), and somatosensory (SSEPs) evoked potentials were studied in 12 patients with Huntington's disease (HD) and were repeated in eight at one and two years. The mean cortical SSEP amplitude was decreased compared with that of age-matched controls, with a trend of decreasing amplitude with increasing duration and severity of illness. The SSEP latency was not significantly different from that of controls.

Normal checkerboard pattern reversal evoked potentials in parkinsonism.

The utility of checkerboard pattern reversal visual evoked potentials in the evaluation of Parkinson disease (Pd) was studied in 25 patients and controls without eye pathology. The results did not reveal differences in potential latency but the amplitude appeared slightly larger in PD than controls. Major intraocular differences were observed only in Pd patients with glaucoma, cataracts or retinal degeneration.