The earlier diabetic retinopathy, macular degeneration and glaucoma—the three most prevalent diseases causing blindness—can be diagnosed, the more successfully they can be treated. Obtaining high-res images of the retina is not so easy, however, due to aberrations caused by imperfections in the cornea and crystalline lens.

Using the same adaptive optics principles that let astronomers see distant objects with such instruments as the Keck Telescope, researchers have created a new device for ophthalmologists to see the eye's retina at the individual cell level. Researchers at Lawrence Livermore National Lab (LLNL), the Indiana University School of Optometry, Boston Micromachines and the University of California, Davis, built three of these adaptive optics–optical coherence tomography (AO-OCT) systems, with help from the National Eye Institute.

"There is a whole history of attempts to image the retina in a way that would help doctors diagnose blinding diseases earlier," says physicist Scot Olivier, who is leading the LLNL work. OCT can make noninvasive, in vivo measurements of the thickness of specific retinal layers, such as the nerve fiber layer, which thins in patients with glaucoma.

Most ophthalmologists already use OCT to measure nerve fiber thickness, Olivier says. If a company could commercialize the adaptive optics as an add-on to OCT, imagine a new generation of devices allowing volumetric retinal imaging with high sensitivity.