Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New optical metrics can identify patients on 'fast track' to decreased vision

25.06.2013
Subtle abnormalities predict which older adults will have faster decline in visual acuity

Sophisticated new optical quality metrics can identify older adults likely to have more rapid age-related declines in vision, suggests a study, "Factors Accounting for the 4-Year Change in Acuity in Patients Between 50 and 80 Years", in the July issue of Optometry and Vision Science, official journal of the American Academy of Optometry. The journal is published by Lippincott Williams & Wilkins, a part of Wolters Kluwer Health.

The study by Darren E. Koenig, OD, PhD, and colleagues of University of Houston College of Optometry defines three advanced optical measures that may help in predicting which older patients will have larger drops in visual acuity over time. "These fast-changing optical metrics allow the identification of patients at risk of being on a fast track to visual acuity loss," comments Anthony Adams, OD, PhD, Editor-in-Chief of Optometry and Vision Science.

Advanced Optical Measures Predict Change in Visual Acuity

Dr Koenig and coauthors performed a follow-up study in 148 older adults, aged 50 to 80 years. In addition to standard visual acuity testing, the participants underwent wavefront error (WFE) testing—a computerized test that can detect subtle abnormalities in the eye's handling of light. About 40 optical components based on WFE were calculated, including 31 different image quality measures, four measures of light scatter in the eye, and four measures of opacification (clouding) of the lens of the eye.

Four years later, visual acuity was measured again. The optical metrics were evaluated for their ability to predict the rate of decline in visual acuity during that time. The goal was to see whether any of the image quality or other metrics could predict which patients would have faster than usual age-related declines in vision.

Overall, the average change in visual acuity during follow-up was loss of 1.6 letters on the standard eye chart. That was consistent with the expected age-related decline.

However, a subgroup of 50 patients had larger changes in visual acuity during follow-up. In this group the average change was loss of 3.4 letters.

Three Significant Predictors of Faster Age-Related Visual Decline

With adjustment for other factors, three optical measures predicted a larger change in visual acuity. These included one optical quality measure ("trefoil"), one measure of optical light scatter ("point spread function entropy"), and one measure of lens clouding (posterior subcapsular cataract).

Together, these three measures accounted for 32 percent of the change in visual acuity in patients with larger-than-expected change in visual acuity. Older age explained at additional two percent of the change.

For the overall sample of 148 eyes, the same factors explained 15 percent of the change in visual acuity. In these slower-changing eyes, older age was the most important predictor.

Advanced optical quality metrics can detect a wide range of minor imperfections in the visual performance of the eye. Computerized WFE analysis is becoming more widely available to detect these subtle vision defects, for example, as part of LASIK and corneal surgery.

The new study suggests that some of these WFE-based metrics may be useful in predicting which patients will have more rapid than usual age-related decline in visual acuity. "Correlations like those found here in fast changing eyes allow the identification of those at risk of being on a fast track to acuity loss," Dr Koenig and coauthors conclude.

"This raises the possibility that those patients may be able to be identified prior to their vision loss simply by measuring these optical components at the outset," Dr Adams adds. "The relatively recent ability to measure many components of the optics of the eye, beyond simply the refractive prescription for glasses or contact lenses, has made this research possible."

To read the article, "Factors Accounting for the 4-Year Change in Acuity in Patients Between 50 and 80 Years", please visit http://journals.lww.com/optvissci/Fulltext/2013/07000/Factors_Accounting_

for_the_4_Year_Change_in_Acuity.3.aspx

About Optometry and Vision Science

Optometry and Vision Science, official journal of the American Academy of Optometry, is the most authoritative source for current developments in optometry, physiological optics, and vision science. This frequently cited monthly scientific journal has served primary eye care practitioners for more than 75 years, promoting vital interdisciplinary exchange among optometrists and vision scientists worldwide.

About the American Academy of Optometry

Founded in 1922, the American Academy of Optometry is committed to promoting the art and science of vision care through lifelong learning. All members of the Academy are dedicated to the highest standards of optometric practice through clinical care, education or research.

About Lippincott Williams & Wilkins

Lippincott Williams & Wilkins (LWW) is a leading international publisher of trusted content delivered in innovative ways to practitioners, professionals and students to learn new skills, stay current on their practice, and make important decisions to improve patient care and clinical outcomes.

LWW is part of Wolters Kluwer Health, a leading global provider of information, business intelligence and point-of-care solutions for the healthcare industry. Wolters Kluwer Health is part of Wolters Kluwer, a market-leading global information services company with 2012 annual revenues of €3.6 billion ($4.6 billion).

Connie Hughes | EurekAlert!
Further information:
http://www.wolterskluwer.com

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

DGIST develops 20 times faster biosensor

24.04.2017 | Physics and Astronomy

Nanoimprinted hyperlens array: Paving the way for practical super-resolution imaging

24.04.2017 | Materials Sciences

Atomic-level motion may drive bacteria's ability to evade immune system defenses

24.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>