Almost all medical imaging to date has used one of three technologies: X-rays, magnetism (MRI), or ultrasound. X-rays alone have been used for almost 120 years now, and although today’s imaging technology has improved vastly over the many years, the fact remains that x-rays, ultrasound, and magnetism are all technologies that, due to many factors, produce coarse images, at least by today’s standards. But what if a very coherent light source was used instead, maybe a laser?
Actually, Optical Coherence Tomography (OCT), which produces images based on the reflections of coherent light, is not a new technology. OCT has been used since the early 1990s, especially in the area of ophthalmology, where the images produced by OCT are 100 times finer than standard images produced by ultrasound. In just the last five years, OCT has become one of the most important retinal imaging techniques used today.
We are forecasting that the laser market for ophthalmology will be just over $300 million dollars worldwide in 2014 and will grow 10% a year, but only a very small part is due to OCT for ophthalmology. While the use of OCT for ophthalmology is very important, and one of the fastest growing medical laser applications in terms of growth rates, the real potential of OCT lies in areas other than the eyes.
While these applications are still very new, OCT is being used to successfully perform minimally invasive cancer biopsies for oral, laryngeal, and esophageal cancer, as well as for genital and bladder cancer. Other uses include the endoscopic imaging of the esophagus, stomach, bile ducts, pancreatic duct, and colon; dental applications; and uses that include imaging veins and arteries.
OCT does have its limits, one of the largest being that the depth of the imaging is limited by the depth that light can penetrate, but work is being done to improve imaging depth. Still, even with its limits, the benefits of OCT over other types of medical imaging is what makes it so intriguing, and OCT has the potential to revolutionize medical imaging overall. While a laser is not required for OCT as a light source, it is often used, which means that anyone who watches the use of lasers in medicine needs to keep a close watch on the area of OCT.