Featured Research

from universities, journals, and other organizations

Developing a test to save eyesight by detecting glaucoma years earlier

Date:
March 25, 2010
Source:
American Chemical Society
Summary:
Scientists are reporting progress toward a test that could revolutionize the diagnosis of glaucoma -- the second leading cause of vision loss and blindness worldwide -- by detecting the disease years earlier than usually happens at present.

A person with advanced glaucoma could have this view of the world, a risk that might be reduced by a new early diagnostic test for the common eye disease.
Credit: National Institutes of Health

Scientists are reporting progress toward a test that could revolutionize the diagnosis of glaucoma -- the second leading cause of vision loss and blindness worldwide -- by detecting the disease years earlier than usually happens at present.

They reported the findings at the 239th National Meeting of the American Chemical Society (ACS) in San Fransisco March 24.

"We are confident that we're moving toward a breakthrough that will allow us to detect glaucoma at its earliest stage," said Chenxu Yu, Ph.D., who headed the study. "We hope it will benefit millions of glaucoma patients and individuals at risk for this devastating eye disease worldwide."

Glaucoma is a group of eye disorders that can damage the optic nerve, which carries visual information from the eye to the brain. It usually occurs when fluid pressure inside the eye slowly increases over time. The fluid presses on the optic nerve and damages it. Glaucoma affects about 70 million people worldwide, including about 2 million in the United States. It damages vision by stealth, with no obvious warning symptoms that would send patients to a doctor. There is no cure, and glaucoma causes irreversible loss of vision.

Doctors now use two main techniques to detect the disease. One test is tonometry, which measures eye pressure by gently touching a special instrument to the outer surface of the eye. The other is ophthalmoscopy, in which an eye specialist uses an instrument called an ophthalmoscope to look directly through the pupil of the eye at the optic nerve. The nerve's color and appearance can indicate the presence of damage from glaucoma.

"All too often, these tests detect glaucoma after the disease has been silently causing damage to the optic nerve," Yu explained. "Years may pass between the first biological change associated with glaucoma inside the eye and diagnosis. We need ways of diagnosing glaucoma earlier, before permanent damage has occurred, so that patients can begin taking medication to control it."

In their ACS report, Yu and colleagues described development and early testing of a potential new early diagnostic method. It gives a mainstay tool in chemistry labs -- Raman spectroscopy -- a potential new life in medicine. The technique as used in chemistry and other laboratories involves focusing a beam of infrared laser light -- invisible to the human eye -- into a test sample to get information about the sample's composition. Yu's method uses Raman spectroscopy to shine laser light through the pupil of the eye. Optic nerve cells (retinal ganglion cells) inside the eye scatter the light, producing a rainbow-like "spectrum" or pattern revealing the chemical composition of the cells. Scientists can then use that snapshot to identify biochemical changes in retinal cells that announce the presence of glaucoma.

Efforts are underway to use Raman spectroscopy -- named for an Indian scientist who won the Nobel Prize for developing it -- elsewhere in medicine (i.e., cancer diagnosis). But Yu described this research as among the first attempts to apply the Raman technology to diagnosis of glaucoma.

Yu and his colleague, Dr. Sinisa Grozdanic, a glaucoma researcher and Director of Animal Research for the Iowa City Veterans Administration Center for Treatment and Prevention of Vision Loss (VA CPTVL), are pleased with results of animal retinal tissue testing from glaucomatous dogs, in which the technique detected glaucomatous changes with 90 percent accuracy, the scientists say.

""This is a very promising technique," said Yu, an assistant professor at Iowa State University in Ames. "We are very excited about the results so far and look forward to additional studies."

The scientists look forward to potential clinical trials in humans. If animal studies go well, and show good efficacy and safety of methodology, the technique could be ready to be used in eye doctor's office within five years, they estimate. The test likely will take about 30 minutes, longer than existing glaucoma tests, but may benefit patients with more accurate diagnosis of disease, Yu said.

The research carries personal meaning for Yu. Doctors have diagnosed him as a being at high-risk for glaucoma. Yu's collaborators in this study also include Qi Wang, a doctoral student at the university; Nicholas Hamouche, M.D., a glaucoma specialist, at McFarland Clinic in Ames, Iowa; and Drs. Matthew Harper and Helga Kecova who are research scientists at the Iowa City VACPTVL. The Iowa State University and Veterans Administration funded the study.


Story Source:

The above story is based on materials provided by American Chemical Society. Note: Materials may be edited for content and length.


Cite This Page:

American Chemical Society. "Developing a test to save eyesight by detecting glaucoma years earlier." ScienceDaily. ScienceDaily, 25 March 2010. <www.sciencedaily.com/releases/2010/03/100324174043.htm>.
American Chemical Society. (2010, March 25). Developing a test to save eyesight by detecting glaucoma years earlier. ScienceDaily. Retrieved October 19, 2014 from www.sciencedaily.com/releases/2010/03/100324174043.htm
American Chemical Society. "Developing a test to save eyesight by detecting glaucoma years earlier." ScienceDaily. www.sciencedaily.com/releases/2010/03/100324174043.htm (accessed October 19, 2014).

Share This



More Health & Medicine News

Sunday, October 19, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Microneedle Patch Promises Painless Pricks

Microneedle Patch Promises Painless Pricks

Reuters - Innovations Video Online (Oct. 18, 2014) Researchers at The National University of Singapore have invented a new microneedle patch that could offer a faster and less painful delivery of drugs such as insulin and painkillers. Video provided by Reuters
Powered by NewsLook.com
Raw: Nurse Nina Pham Arrives in Maryland

Raw: Nurse Nina Pham Arrives in Maryland

AP (Oct. 17, 2014) The first nurse to be diagnosed with Ebola at a Dallas hospital walked down the stairs of an executive jet into an ambulance at an airport in Frederick, Maryland, on Thursday. Pham will be treated at the National Institutes of Health. (Oct. 16) Video provided by AP
Powered by NewsLook.com
Raw: Cruise Ship Returns to US Over Ebola Fears

Raw: Cruise Ship Returns to US Over Ebola Fears

AP (Oct. 17, 2014) A Caribbean cruise ship carrying a Dallas health care worker who is being monitored for signs of the Ebola virus is heading back to Texas, US, after being refused permission to dock in Cozumel, Mexico. (Oct. 17) Video provided by AP
Powered by NewsLook.com
Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

Spanish Govt: Four Suspected Ebola Cases in Spain Test Negative

AFP (Oct. 17, 2014) All four suspected Ebola cases admitted to hospitals in Spain on Thursday have tested negative for the deadly virus in a first round of tests, the government said Friday. Duration: 00:55 Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins