ABSTRACT
Optical coherence tomography (OCT) is an imaging modality that uses a focused light source to create a cross-sectional image of the retina. OCT technology has more in common with MRI and ultrasound than it does with photography, but ophthalmic imagers perform millions of these scans each day as part of their daily responsibilities. The introduction and adoption of OCT induced a paradigm shift in clinical ophthalmology that radically changed the way ophthalmologists treated disease. For the first time, OCT allowed them to view the individual retinal layers in vivo to evaluate and measure responses to treatment. Prior to OCT, physicians relied on retinal examination or stereo imaging and spatial comparison in fundus photography and angiography to visualize the height of a lesion or the position of a hemorrhage relative to the layers of the retina. OCTs are marketed to be used mydriatically or non-mydriatically. However, in the offices of most clinical ophthalmologists, the patients are already dilated.
