Reviewed by Robert Stamper, MD
Optical coherence tomography (OCT) angiography could yield important insights into glaucoma, according to Robert Stamper, MD.
The new imaging technique shows significant loss of blood vessels around the optic nerve in patients with glaucoma, said Dr. Stamper, professor of ophthalmology, University of California, San Francisco.
OCT tomography scanners can create about 70,000 images of the back of the eye in 3 seconds. Using artificial intelligence, they apply corrections for blinking and microsaccades, said Dr. Stamper.
“If you have a constant background—the retina—and something is moving across it, and you know how quickly you’ve taken the photos, and the distance, you can sort out the movement that’s occurred from the stable background,” he explained. “That’s basically what OCT angiography depends upon.”
This analysis produces pictures of blood vessels—capillaries, as well as the arterioles and venules in the retina. Its in-depth scans can distinguish vascular layers.
“Motion correction is applied to get rid of saccades, so you get very nice pictures of both the capillary density and sometimes the structure of the capillaries,” said Dr. Stamper.
The pictures produced resemble a flat preparation of the whole retina. For that reason, retina specialists have been the first ophthalmologists to begin using the new technology. They are using it to analyze macular degeneration.
“I don’t think you need to be an expert to pick up holes,” Dr. Stamper said.
Robert Stamper, MD
This article was adapted from Dr. Stamper’s presentation at the 2018 meeting of Glaucoma 360. He did not indicate any proprietary interest in the subject matter.