[Editors] MIT team takes high-res, 3-D images of eye

[Elizabeth Thomson]

MIT News Office
Massachusetts Institute of Technology
Room 11-400
77 Massachusetts Avenue
Cambridge, MA  02139-4307
Phone: 617-253-2700
http://web.mit.edu/newsoffice/www

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MIT team takes high-res, 3-D images of eye
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For Immediate Release
TUESDAY, MAY 1, 2007
Contact: Elizabeth A. Thomson, MIT News Office
Phone: 617-258-5402
Email: thomson at mit.edu

PHOTO AVAILABLE

CAMBRIDGE, Mass.--In work that could improve diagnoses of many eye 
diseases, MIT researchers have developed a new type of laser for 
taking high-resolution, 3-D images of the retina, the part of the eye 
that converts light to electrical signals that travel to the brain.

The research will be presented at the Conference on Lasers and 
Electro-Optics and the Quantum Electronics and Laser Science 
Conference in Baltimore on May 10.

The new imaging system is based on Optical Coherence Tomography 
(OCT), which uses light to obtain high-resolution, cross-sectional 
images of the eye to visualize subtle changes that occur in retinal 
disease. OCT was developed in the early 1990s by MIT Professor James 
Fujimoto, Eric Swanson at MIT Lincoln Laboratory and collaborators; 
Fujimoto is an author of the report to be presented in May.

"Within the last few years optical coherence tomography has become a 
standard diagnostic for ophthalmology. New techniques are now 
enabling dramatic increases in image acquisition speeds. These 
advances promise to enable new and powerful three-dimensional 
visualization methods which could improve early diagnosis of disease 
and treatment monitoring," said Fujimoto, who holds appointments in 
MIT's Department of Electrical Engineering and Computer Science and 
the Research Laboratory of Electronics.

Conventional OCT imaging typically yields a series of two-dimensional 
cross-sectional images of the retina, which can be combined to form a 
3-D image of its volume. The system works by scanning light back and 
forth across the eye, measuring the echo time delay of reflected 
light along micrometer-scale lines that, row by row, build up 
high-resolution images.

Commercial OCT systems scan the eye at rates ranging from several 
hundred to several thousand lines per second. But a typical patient 
can only keep the eye still for about one second, limiting the amount 
of three-dimensional data that can be acquired.

Now, using the new laser, researchers in Fujimoto's group report 
retinal scans at record speeds of up to 236,000 lines per second, a 
factor of 10 improvement over current OCT technology.

Future clinical studies, as well as further development, may someday 
enable ophthalmologists to routinely obtain three-dimensional "OCT 
snapshots" of the eye, containing comprehensive volumetric 
information about the microstructure of the retina. Such snapshots 
could potentially improve diagnoses of retinal diseases such as 
diabetic retinopathy, glaucoma and age-related macular degeneration.

Fujimoto's colleagues on the work are Robert Huber, a visiting 
scientist at MIT now at the Ludwig-Maximilians University in Germany, 
Desmond C. Adler and Vivek Srinivasan. Adler and Srinivasan are both 
graduate students in EECS.

The current research was sponsored by the National Science 
Foundation, the National Institutes of Health and the Air Force 
Office of Scientific Research.

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