Mary Ellen Ciganovich has no definite medical answer why working on a computer initiates a multiple sclerosis attack in her.
What she does know is that wearing yellow-tinted "computer glasses" prevents the attacks.
But, occasionally, she forgets to put them on.
"I just worked on my computer for awhile. I forgot to put my glasses on and, when I got up, my legs are now shaky and I am queasy," says Ciganovich, 62, a writer and inspirational speaker from Ooltewah.
Sure, everyone knows eyeglasses are meant to help improve your eyesight, but these days, new designs in lenses are being used for other medical reasons. Tinted glasses -- often yellow -- are being marketed to those who spend most of their day in front of computer screens -- especially hardcore video gamers -- to reduce eye strain, now with the medical-sounding name of Computer Vision Syndrome.
But there also are glasses designed to help with serious issues such as hemianopia, a loss of vision in either the right or left sides of both eyes often caused by brain injury or stroke. There are also lenses that are touted to help with dyslexia, but those claims are disputed by some ophthalmologists.
"The eyes are fascinating," says Dr. Leslie Draper, an optometrist at Chattanooga Eyecare on Market Street. "We can tell by your eye health exam many systemic conditions. We often are the first physicians they come to because of vision issues and, ultimately, there is a systemic cause affecting their vision. Diabetes and high blood pressure are common diseases found on routine exams."
For less-serious ailments such as strained eyes, especially when caused by computers, tinted glasses will help, says Draper.
"Most will benefit from wearing a pair of glasses to reduce the glare and eye strain from long-term computer use," she says. "These are nonglare lenses and anti-fatigue lenses. Anyone with or without a prescription would benefit from a computer pair of glasses."
People who have been diagnosed with hemianopia may be required to wear "prism glasses." Those who suffer from the disease have problems with mobility, bumping into objects, increased incidence of falls and accidents and reading problems.
"With this condition, a portion of their field of vision is missing -- they may not see the right side of objects," Draper explains. Prism glasses "direct the images into their line of sight."
The type of lenses described for stroke victims are dependent on what area was affected by the stroke, she says.
ChromaGen say its lenses, which come in several colors, can help people with dyslexia by removing the tendency for words to seem to move on the page when they're reading, leading to relief from headaches, nausea and eye strain. The company also says the colored lenses help those with colorblindness.
But the only scientific test done on the validity of the lenses helping dyslexia was paid for by ChromaGen and has been questioned by ophthalmologists. A 2011 report led by Dr. Sheryl Handler, a pediatric ophthalmologist in Encino, Calif., stressed that "Dyslexia is not a visually based disorder. There is definitely no evidence that the lenses will improve dyslexia."
For most people, however, the biggest issue is vision problems triggered by long-term computer use.
"Our eyes become dry due to less blinking. The monitor's glare from screen cause increase in fatigue throughout the long day," Draper says. "Fatigue can feel like a headache and can cause you to have more headaches.
"Your eyes will just feel better and your day a little easier with computer lenses. That is why I wear my glasses at work," she says. "Since we are a paperless office, I find my eyes are more fatigued if I don't wear them."
Ciganovich, a writer, educator and inspirational speaker, says she was spending a lot of time on the computer when she suffered, what she believes, to be the computer-triggered MS attack.
"I worked longer than usual and began to feel dizzy, thinking I was coming down with the flu," she recalls. "I knew the attack was related to the computer.
"My husband already had special yellow-tinted glasses he used when on the computer. He gave me his pair to try and, as long as I use them, I do not get dizzy or have an attack. All I can say is they work, and when you have MS (and) you find something that works, you keep doing it."
Children who spend a lot of time on the computer, whether it's doing homework or playing video games, should also wear computer glasses, Draper says. And you should limit the amount of time your children stare at a computer screen, she says.
"This can be a tablet, cellphone or video game. Give them a 20-minute limit, then encourage distance activities or playing outside."
Robin Derryberry, 53, owner of Derryberry Public Relations in Chattanooga, wears trifocals, with lenses that are prescribed for computer use.
"The top part of my glasses are clear, while the middle section allows me to work on the computer, and the bottom allows me to see fine print," she says. "I don't wear them all day, just as needed. They aren't tinted, but they are nonglare."
Occupation and marketing manager Kori Wariner, 42, of Chattanooga, says prolonged use of the computer caused her to have dizziness, burning eyes and headache. So she turned to plain old reading glasses.
"My eye doctor advised me to try reading glasses to alleviate the vibration coming from the computer screen. It worked," she says.
"It's a result of my right eye being nearsighted and my left being farsighted, resulting in the inability of my eyes to focus on the same point due to overlap. I still only wear contacts and occasional prescription (not reading) glasses, and only use my reading glasses when in front of the computer."
Contact Karen Nazor Hill at firstname.lastname@example.org or 423-757-6396.