What imaging technique provides information about blood flow through retinal vessels?

Fluorescein angiography is the imaging technique that provides detailed information about blood flow through the retinal vessels. This method involves injecting a fluorescent dye into the bloodstream, which travels to the eye and highlights the blood vessels in the retina. As the dye flows through the vessels, a series of photographs are taken at various intervals. This allows clinicians to visualize the circulation, identify any abnormalities, and assess conditions such as retinal vascular diseases, ischemia, and other pathologies related to blood flow.

Other imaging techniques mentioned serve different purposes. For instance, ultrasound biomicroscopy primarily helps visualize the anterior segment of the eye and is not focused on vascular imaging. Optical coherence tomography offers high-resolution cross-sectional images of the retina but does not specifically measure blood flow. Electroretinography is a functional test that evaluates the electrical response of the retina to light but does not provide insights into blood flow dynamics. Thus, fluorescein angiography is the correct choice when seeking information on the blood flow through retinal vessels.