Contrast Important for Those with Vision Problems

From the WebMD Archives

May 23, 2000 -- It often begins as a small distortion in the center of the field of vision. As it progresses, this area gets larger and larger until it becomes hard to see things right in front of you. More than 13 million people are affected by macular degeneration, which is the leading cause of legal blindness in those over 50.

The macula is the part of the eye that lets us see fine detail at the center of our field of vision. When problems occur in this area, things in the middle of the field of vision become blurred, while our ability to see at the edges remains. This leads to problems with driving, recognizing people at a distance, and other sight-related tasks. Being unable to read is usually the worst part.

Charlotte A. Hazel and colleagues from the Vision Science Research Institute in England recently looked at how vision relates to quality of life for those people with macular disease. Twenty-eight patients were given a comprehensive assessment of how well their eyes were functioning. This was followed by a questionnaire that asked them about such quality of life issues as their ability to get around, read, and participate in leisure activities.

"Reading performance is strongly associated with vision-related quality of life," write Hazel and her group in the journal Investigative Ophthalmology and Visual Science. "The impact that reading ability has on these patient's overall opinion of their vision is understandable when considering the importance of an intact central visual field on tasks such as reading, and the importance of these tasks in daily life."

Bright lights increase the contrast between the page and the writing, which makes it easier to read numbers and letters. The research by Hazel and her colleagues showed that contrast might be even more important than print size in this instance.

Many low-vision aids, such as hand-held magnifying glasses, combine magnification and bright lights to help the person see. Special telescopes may be used to see things far off. Higher-tech solutions include using big and bold type on a computer or using closed circuit TV cameras to project the words onto a screen.

Other useful devices include watches and timers with big numbers, attachments to phones that allow a person to see better so they can dial, and large print books. Many calculators and similar devices have been "taught how to talk."

"Contrast sensitivity seems to be important in these patients, and therefore has implications on the design of reading materials," they write. "Consideration should be given by manufacturers when labeling products so that maximum word visibility can be obtained."

Albert O. Edwards, MD, an ophthalmologist at the University of Texas Southwestern Medical Center in Dallas, tells WebMD the study highlights the importance of contrast when communicating with those who have macular problems. For instance, people going to the supermarket may take along a flashlight, in addition to a magnifying glass, to get more contrast between the paper and the letters on cans or other packaging.

"Express your needs to those you come into contact with," he says. "You should talk to others about what they need to do to communicate with you. Using a fine red pen on yellow paper might look nice, but would much be harder to read than a message left with a black marker on white paper."

William E. Smiddy, MD, from the Bascom Palmer Eye Institute in Miami, suggests some other considerations for those with low-level vision.

"When shopping for appliances and other items, always be aware of how easy they are to use," he says. "For instance when buying a new range, pay attention to whether you can read the dials; maybe a different color of the digital readouts will be better. Buying an appliance is not only finding a color you like, but also one that helps you use it."

Perhaps the most important point is to remind people with macular disease that they should not be embarrassed if they can't read something. If you suffer from it, tell loved ones and others what they can do to make communication with you easier.

Vital Information:

  • Macular degeneration occurs when the part of the eye responsible for fine detail in the center of vision begins to deteriorate.
  • For optimal reading abilities, people with macular degeneration need sharp contrast between the page and the writing.
  • To help aid reading, many tools are available, such as magnifying glasses, special telescopes, large-print books, and even a computer that can project large print onto a screen.