OCT: From Today’s Stage to the Future

Optical coherence tomography (OCT) is based on the principle of optical reflectometry and has been referred to as “an ultrasound using light.” OCT patient imaging with the first prototype began in 1993. When patient imaging began, image resolution was good, but acquisition times were slow. After improving the process, the first OCT became commercially available in 1996 and has since undergone several upgrades that have resulted in the OCT 3, which is considered state of the art. It has a resolution of 10 microns and an improved speed. Currently, there are approximately 300 OCT3 machines in use world wide. Two recent advances have occurred in OCT technology: improved resolution and improved speed. The ultrahigh resolution OCT, which became commercially available in 2002, uses a wider bandwidth, provides clearer distinction of retinal layers, and has a resolution of down to 2 microns. The “ultrafast” OCT uses spectral technology. These advances in OCT provide better options for ocular imaging, and studies are underway to determine whether they can also lead to better patient outcomes.