What does OCT angiograph scan?

What does OCT angiograph scan?

• A. Visualizes the retina by measuring photoreceptor density
• B. Measures retinal thickness only
• C. Visualizes the retinal microvasculature by measuring light reflectance from moving red blood cells
• D. Maps corneal curvature

Answer: (C)

OCT angiography reveals the tiny blood vessels by using motion contrast. It takes repeated scans of the same retinal location and looks for changes in the signal caused by moving red blood cells. Where blood cells are moving, the OCT signal decorrelates between scans, and those regions form the vascular map. This lets us visualize the retinal microvasculature without injecting dye, including the superficial and deep capillary networks. It isn’t about measuring photoreceptor density, merely thickness, or corneal curvature; those are different structural assessments. So the best description is that OCT angiography visualizes the retinal microvasculature by detecting light reflectance changes from moving red blood cells.

OCT angiography reveals the tiny blood vessels by using motion contrast. It takes repeated scans of the same retinal location and looks for changes in the signal caused by moving red blood cells. Where blood cells are moving, the OCT signal decorrelates between scans, and those regions form the vascular map. This lets us visualize the retinal microvasculature without injecting dye, including the superficial and deep capillary networks. It isn’t about measuring photoreceptor density, merely thickness, or corneal curvature; those are different structural assessments. So the best description is that OCT angiography visualizes the retinal microvasculature by detecting light reflectance changes from moving red blood cells.