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Janet, You just reminded me. My eye appt. yesterday was actually a blessing,I think. I do need a lens change but the blurring or cloudy vision was what I went for and I am told that it is due to a small cataract. I can live with that. Hopefully the new lenses will take care of the other malfunctions. Shirley -----Original Message----- From: janet marie paterson <[log in to unmask]> To: [log in to unmask] <[log in to unmask]> Date: Wednesday, February 09, 2000 8:56 AM Subject: PMID: 10656512: Visual contrast response functions in PD >Visual contrast response functions in Parkinson's disease: >evidence from electroretinograms, visually evoked potentials and psychophysics. > >OBJECTIVES: Visual contrast detection thresholds and suprathreshold contrast discrimination thresholds were compared to luminance and flash/pattern electroretinograms (ERG) and visually evoked potentials (VEP) in patients with Parkinson's disease (n = 31), patients with multiple system atrophy (n = 6), patients with progressive supranuclear palsy (n = 6) and control patients without central nervous disease (n = 33). > >METHODS: The stimuli were luminance modulated full-field (flash) or horizontally oriented sinewave gratings (pattern), the latter having either a low (0.5 cycles/deg) or medium (4.0 cycles/deg) spatial frequency. > >Stimulus contrast ranged from 10 to 80% so that contrast response functions could be derived. > >RESULTS: Contrast thresholds were higher in the patients with Parkinson's disease than in the control patients. > >Contrast discrimination thresholds were also somewhat elevated in patients with Parkinson's disease. > >Pattern ERG amplitudes were significantly reduced in patients with Parkinson's disease for the medium spatial frequency stimulus, but less for the low spatial frequency and flash stimuli. > >CONCLUSIONS: Our results suggest that Parkinson's disease impairs contrast processing in the retina. > >VEP amplitudes did not significantly differ between the groups for the conditions tested. > >Patients with progressive supranuclear palsy also showed impaired contrast perception and reduced ERG amplitudes, whereas patients with multiple system atrophy were less impaired. > > >Clin Neurophysiol 2000 Jan;111(1):66-74 >Langheinrich T, Tebartz van Elst L, Lagreze WA, >Bach M, Lucking CH, Greenlee MW >Neurologische Universitatsklinik, Universitat Freiburg, Germany. >PMID: 10656512, UI: 20120305 > ><A HREF="http://www.ncbi.nlm.nih.gov/PubMed/">http://www.ncbi.nlm.nih.gov/PubMe d/</A> > >janet paterson >52 now / 41 dx / 37 onset >a new voice: http://www.geocities.com/janet313/ >613 256 8340 PO Box 171 Almonte Ontario Canada K0A 1A0