 |
 |
On 28 Jan 00 at 14:06, judith richards wrote: SNIP > Parkinson's hinders patients' ability to distinguish contrast SNIP > "Visual contrast problems are not seen in phase one (of the disease) but > are there at grades two through five. In the more advanced grades ... > four and five, these are extremely severe. > I first noticed my eyes were changing (contrast-wise) about 20 - 25 years ago. When moving from light to dark (and vice-versa) my eyes did not adapt as quickly as they once did and I found it necessary to have two pairs of glasses (clear & tinted) on the dash when driving and simply change glasses to adjust vision & comfort level. > > "I think in terms of becoming clinically very significant this is a > concern only in the advanced stages ... four and five. I don't think we > could push it to say that phase two patients have visual problems but > there are changes nevertheless." > I agree "there are changes nevertheless". Some can be written off to age as we approach our fifties, but my vision seems "different" than others my age. > > Clinically, he said, this means doctors should listen when Parkinson's > patients bring complaints such as not being able to see well at night. > > "Typically these patients are found to have normal acuity and no eye > disease that would explain their visual complaints. Many undergo > repeated visual exams and needless changes in eyeglasses in the effort > to see better. This can be very frustrating for these patients. > I've tried different eye specialists and many different lenses. For myself I found the trifocals and bifocals to be annoying. (The "progressive focus" lenses are a total disaster for me) I've finally settled on photogrey tinted lenses for my normal everyday glasses and untinted reading glasses for home only reading only. My original visual problem is that I require glasses for distances over 20 feet, so I've always worn glasses to drive and taken them off at work and around the house. I can sit close and watch TV without glasses or backoff and wear my glasses. I use Opera as my browser on the web (as opposed to IE5 or Netscape) because you can "one click" (on the keyboard) to black on a white background if you find difficulties with contrast. You can also one click zoom. There many keyboard shortcuts but here are the zoom options as an example... Zoom up 10% + or 0 Zoom down 10% - or 9 Restore Zoom to 100% 6 or * Zoom up by 100% 7 or CTRL+"+" Zoom down by 100% 8 or CTRL+"-" If you have trouble using a mouse you might like Opera for it's keyboard navigation.... http://www.opera.com/keyboard.html > > "So we think an analogy to what we are doing in the lab is what a > Parkinson's patient sees at night when the light is fading at dusk ... > or not seeing at night when the ambient lighting is low." > > He said the take-away message is that patients with this problem should > not be driving. He said they also need to increase the lighting in their > hallways, stairwells and bathrooms. > > "Often they can't see the steps and they tend to fall down them. Make > sure steps are clearly contrasted in the home and places like garages. > This can be done simply by the use of tape to edge stairs, for example." > I found the multifocus (trifocal, bi-focal, progressive focal) lenses to be particularly dangerous on stairs. > > Dr. Hutton said colour perception is also affected by progression with > the whole colour range diminishing in time. > > "It is quite surprising what these people cannot see on our research > testing screen. We have worked with coloured lenses a bit but there are > no major conclusions other than we did not see any dramatic > improvements." > Dramatic improvements? Perhaps not but give me photogrey for comfort in all light levels and all contrasts. > > c Copyright 1999 The Medical Post. All rights reserved. > ~~~~ > Judith Richards > THANKYOU VERY MUCH FOR THIS ARTICLE ... murray [log in to unmask]