Color vision in Parkinson’s disease and essential tremor
Article first published online: 6 SEP 2010
© 2010 The Author(s). European Journal of Neurology © 2010 EFNS
European Journal of Neurology
Volume 18, Issue 4, pages 577–583, April 2011
How to Cite
Oh, Y.-S., Kim, J.-S., Chung, S.-W., Song, I.-U., Kim, Y.-D., Kim, Y.-I. and Lee, K.-S. (2011), Color vision in Parkinson’s disease and essential tremor. European Journal of Neurology, 18: 577–583. doi: 10.1111/j.1468-1331.2010.03206.x
- Issue published online: 16 MAR 2011
- Article first published online: 6 SEP 2010
- Received 25 March 2010 Accepted 10 August 2010
- color vision;
- essential tremor;
- Farnsworth–Munsell 100 Hue test;
- Parkinson’s disease
Background and purpose: Decreased visual function is one of the non-motor dysfunctions of Parkinson’s disease (PD). Recent evidences suggest that essential tremor (ET) is not ‘pure’ motor disorder and there is growing evidence that this disease is a multiple-system disorder. In some cases, it is difficult to differentiate ET from PD. In addition, there is considerable controversy regarding the relationship between PD and ET. The objective of this study was to compare color discrimination dysfunction amongst patients with PD and ET and to investigate the clinical relevance.
Methods: Case–control comparisons of 54 patients with PD, 36 patients with ET, and 34 age-matched controls were performed. All cases underwent Farnsworth–Munsell 100 Hue test (FMT) and clinical assessments on medication. In addition, the association between color vision abnormalities and motor handicaps was investigated.
Results: There were significant differences in the total error scores (TES) of the FMT amongst the three groups; patients with the PD had higher TES than the patients with ET and the controls after adjustments for age. In addition, the motor symptom severity in PD correlated with the FMT abnormalities, especially with regard to the axial symptoms.
Conclusion: The results of this study suggest that color vision abnormalities may be one of the non-motor clinical characteristics of PD-related dysfunction in contrast to ET. In addition, the severity of axial motor symptoms was closely related to visual dysfunction. Confirmation of these findings as well as the mechanisms underlying these results requires further study.