In recent years new techniques of optic nerve imaging have become available, such as optical coherence tomography or OCT. It is a laser-based, noncontact, noninvasive imaging technique that is capable of obtaining high resolution images of the retina and its components.
OCT is similar to ultrasound imaging except that light rather than sound waves are used. This results in a much higher resolution of approximately 10 microns, which is one millionth of a meter, in the retina. OCT provides direct, real-time, cross-sectional images of retinal tissue layers, allowing improved resolution and diagnostic capabilities of a variety of eye diseases or disorders. OCT has the capability of measuring the retinal nerve fiber layer thickness in medical conditions such as glaucoma, macular degeneration, diabetes, and retinal detachment. Early detection can aid in better control of disease progression and treatment.