Optical coherence tomography (OCT) is an imaging technology that can perform non-contact cross-sectional imaging of retinal and choroidal tissue structure in real time by measuring the intensity of reflected light. Tomographic images are generated by scanning the optical probe beam across the tissue structure of interest. OCT has become one of the most widely used imaging technologies by ophthalmologists. Its advantages include being a non-contact imaging modality, having micron-level resolution, producing a digital image that can be viewed electronically, and providing a reproducible quantitative measurement. New functional OCT including Doppler OCT and OCT angiography may allow an assessment of retinal blood flow and do away with the need for the more invasive fluorescein angiography (FA) test.
Thus, if the diagnostic data provided by functional OCT are at least equivalent or superior to those achieved by FA, patients and healthcare providers could realize a substantial benefit in utilizing this technology in the evaluation of retinal vascular disease. Even in the scenario in which an FA is not usually clinically indicated, OCT angiography may provide information over that of standard OCT and clinical examination and history, that might help clinicians better understand the etiology of the disease, and may even help inform treatment response.