A pilot study to monitor Graves' Ophthalmopathy with a combination of pattern-reversal and motion-onset visual evoked potentials
Abstract
Objective: The aim of this pilot study was to evaluate the efficacy of visual evoked potentials (VEPs) in the monitoring of visual function during a high-dose intravenous steroid pulse therapy and apheresis treatment of severe Graves' ophthalmopathy (GO). Patients and Research Design: Nine patients with severe and active GO were treated with high-dose Methylprednisolone (1 g/day 3 times within 1 week, then 0.5 g/day 7 times for 2 weeks) combined with plasma filtration (twice a week in weeks 1, 2, 4, 7, and 10).
Pattern-reversal and motion-onset VEPs were examined three times, pre-treatment, after steroid pulses, and after the last apheresis. Results: After ten steroid pulses, the visual acuity was significantly better and the pattern-reversal VEP amplitudes (element size of only 20') had a similar trend for improvement.
However, this effect disappeared after seven weeks when only apheresis treatment was performed. No significant changes in the latencies of any of the tested VEP variants were found in relationship to the treatment.
Conclusion: Only the observed large intra-individual variability of the VEP parameters between repeated examinations of patients with the shortest duration of GO might be recognized as a marker for functional changes of the visual pathway due to GO. Although this pilot study cannot provide a definite view on the usefulness of the extended set of VEPs in objective monitoring of GO, it seems that the steroid pulse therapy effect is detectable in contrast to the lack of influence by apheresis on the electrophysiological parameters tested.