Professor James Fujimoto, center, and students use the eye-imaging technique he began developing in the early 1990s.

Professor James Fujimoto, center, and students use the eye-imaging technique he began developing in the early 1990s.


The new imaging system is based on Optical Coherence Tomography (OCT), which uses light to obtain high-resolution, cross-sectional images of the eye that can reveal subtle changes due to retinal disease.

Conventional OCT typically yields 2D cross-sectional images of the retina, which combine to form a 3D image. It works by scanning light back and forth across the eye, measuring the 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 several hundred to several thousand lines/sec. But typical patients can only keep their eyes still for about a second, limiting the 3D data acquired. Using the new laser, MIT reports retinal scans at speeds up to 236,000 lines/sec, a tenfold improvement over current OCTs.

Further development may let ophthalmologists routinely obtain 3D OCT snapshots of the eye and comprehensive volumetric information about the retina's microstructure. Such snapshots could improve diagnoses of diabetic retinopathy, glaucoma, and age-related macular degeneration.