Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study of living eye in real time now possible with optics technology

17.02.2003


UH Researchers Focus On Diagnosing Eye Disease Using Adaptive Optics



A new optics technology is providing scientists with real-time microscopic images of the living retina, and may allow doctors to focus in on earlier diagnosis and treatment of diseases such as diabetes and glaucoma.

University of Houston researchers are using a technology called adaptive optics to peer inside the eyes of human subjects and for the first time get clear, sharp images of features such as blood flow in the eye’s retina. Until now, clear images of the living retina were not possible because the eye’s own structure interferes with the imaging process.


“Everyone suffers from natural irregularities in the cornea and lens of the eye, and even in people with normal, 20/20 vision, these defects prevent the eye from focusing light from the world into a nice sharp image on the retina,” says Austin Roorda, assistant professor of optometry at the University of Houston. “Eye doctors have to look through these same defects when they examine a patient’s retina, and the image they see is not very clear, limiting the amount of information they can get.”

A clear view of the retina is key to the early diagnosis of diseases such as glaucoma, which produces changes in the nerves in the eye, and diabetes, which affects blood flow in the retina.

“The eye is a wonderful instrument, but its optics are not particularly good, and this has limited our ability to clearly see what’s happening in there,” Roorda says.

Using adaptive optics, researchers accurately measure the defects in the cornea and the lens and compensate for them to produce detailed microscopic images and video of human retinas. In his lab, Roorda and his colleagues have built a scanning laser ophthalmoscope, the only device of its kind that incorporates adaptive optics.

“We get a much clearer picture of the retina than any other technology can produce, with the added advantage that the data we get is in real time,” Roorda says.

Roorda’s scanning laser ophthalmoscope won’t be in clinics any time soon, but he says it’s a prototype for the next generation of such devices. He and colleagues at four other institutions, led by the University of Rochester, recently received a $10 million, five-year grant from the National Institutes of Health to build more adaptive optics devices.

Roorda will present information about his research Feb. 16 in Denver at the annual meeting of the American Association for the Advancement of Science.

During the past year, Roorda has examined normal eyes in about 30 people, and four people with medical conditions that affect the eyes. He and his UH team have seen capillaries – the smallest blood vessels in the retina – and the white blood cells flowing through them. Tracking the movement of white blood cells helps them measure the rate of blood flow, as well as monitor their specific behavior.

“Right now we’re focusing on understanding what normal eyes look like with this instrument. This is a whole new view of the retina, and we’re developing protocols for imaging patients,” Roorda says.

The UH researchers are working with a physician at the Texas Medical Center and plan to look at patients with diabetes, for example, to examine their blood flow dynamics. In diabetics, it is thought that white blood cells tend to be sticky and may move differently through the capillaries than they do in normal retinas. Roorda’s team also plans to look at glaucoma patients, whose retinal nerves have been changed by the disease, and people with changes or losses in their cone photoreceptors.

“We should be able to watch the progression of these types of diseases,” he says.

In the lab, Roorda’s test subject sits in front of the device, and his head is kept still by having the person bite down on a custom-fit mouthpiece mounted in place. The adaptive optics setup involves shining a weak laser into the subject’s dilated eye. The laser light reflects off the retina and is scattered back out of the eye, where it is picked up by a wavefront sensor. This component measures the defects in the lens and cornea and feeds that information back to a deformable mirror, which is the backbone of the device.

“The mirror is made of glass, which is flexible, and it is supported on its back surface by a grid of electronically controlled small pistons that ever-so-slightly change the mirror’s shape in such a way as to focus the scattered light into parallel rays. This, and a lot of sophisticated computer code, is what then produces the clear, corrected image,” Roorda says.

One of the future clinical applications of Roorda’s device might be microretinal surgery, where surgeons need a clear view of an area they would like to treat.

“The way we use our laser to scan the retina to produce an image, it may be possible to use the technique for treatment. While you’re imaging a microaneurysm, for example, if we could track that feature we may be able to then turn on a treatment laser and blast it with the same precision that we can see it,” he says.

Roorda earned his Ph.D. in physics at the University of Waterloo in Canada and began his work in adaptive optics as a post-doctoral researcher at the University of Rochester. He joined the UH faculty in 1998. His research is funded by the National Institutes of Health, as well as by the National Science Foundation through the Center for Adaptive Optics at the University of California at Santa Cruz.

SOURCE: Roorda, 713-743-1952; aroorda@uh.edu


About the University of Houston

The University of Houston, Texas’ premier metropolitan research and teaching institution, is home to more than 40 research centers and institutes and sponsors more than 300 partnerships with corporate, civic and governmental entities. UH, the most diverse research university in the country, stands at the forefront of education, research and service with more than 34,400 students.

Amanda Siegfried | University of Houston
Further information:
http://www.uh.edu/admin/media/nr/2003/022003/adaptiveopts021603.html
http://www.uh.edu/admin/media/sciencelist.html

More articles from Health and Medicine:

nachricht Researchers develop high-performance cancer vaccine using novel microcapsules
25.05.2020 | Chinese Academy of Sciences Headquarters

nachricht Blood flow recovers faster than brain in micro strokes
25.05.2020 | Rice University

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: I-call - When microimplants communicate with each other / Innovation driver digitization - "Smart Health“

Microelectronics as a key technology enables numerous innovations in the field of intelligent medical technology. The Fraunhofer Institute for Biomedical Engineering IBMT coordinates the BMBF cooperative project "I-call" realizing the first electronic system for ultrasound-based, safe and interference-resistant data transmission between implants in the human body.

When microelectronic systems are used for medical applications, they have to meet high requirements in terms of biocompatibility, reliability, energy...

Im Focus: When predictions of theoretical chemists become reality

Thomas Heine, Professor of Theoretical Chemistry at TU Dresden, together with his team, first predicted a topological 2D polymer in 2019. Only one year later, an international team led by Italian researchers was able to synthesize these materials and experimentally prove their topological properties. For the renowned journal Nature Materials, this was the occasion to invite Thomas Heine to a News and Views article, which was published this week. Under the title "Making 2D Topological Polymers a reality" Prof. Heine describes how his theory became a reality.

Ultrathin materials are extremely interesting as building blocks for next generation nano electronic devices, as it is much easier to make circuits and other...

Im Focus: Rolling into the deep

Scientists took a leukocyte as the blueprint and developed a microrobot that has the size, shape and moving capabilities of a white blood cell. Simulating a blood vessel in a laboratory setting, they succeeded in magnetically navigating the ball-shaped microroller through this dynamic and dense environment. The drug-delivery vehicle withstood the simulated blood flow, pushing the developments in targeted drug delivery a step further: inside the body, there is no better access route to all tissues and organs than the circulatory system. A robot that could actually travel through this finely woven web would revolutionize the minimally-invasive treatment of illnesses.

A team of scientists from the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart invented a tiny microrobot that resembles a white blood cell...

Im Focus: NASA's Curiosity rover finds clues to chilly ancient Mars buried in rocks

By studying the chemical elements on Mars today -- including carbon and oxygen -- scientists can work backwards to piece together the history of a planet that once had the conditions necessary to support life.

Weaving this story, element by element, from roughly 140 million miles (225 million kilometers) away is a painstaking process. But scientists aren't the type...

Im Focus: Making quantum 'waves' in ultrathin materials

Study co-led by Berkeley Lab reveals how wavelike plasmons could power up a new class of sensing and photochemical technologies at the nanoscale

Wavelike, collective oscillations of electrons known as "plasmons" are very important for determining the optical and electronic properties of metals.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

International Coral Reef Symposium in Bremen Postponed by a Year

06.04.2020 | Event News

 
Latest News

Oriented hexagonal boron nitride foster new type of information carrier

25.05.2020 | Materials Sciences

The lower mantle can be oxidized in the presence of water

25.05.2020 | Earth Sciences

I-call - When microimplants communicate with each other / Innovation driver digitization - "Smart Health“

25.05.2020 | Medical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>