Optical coherence tomography: cellular and functional retinal imaging

Wolfgang Drexler, PhD, was instrumental in the development of optical coherence tomography (OCT) andhas contributed significantly to advances such as ultra high-resolution OCT. But befitting someonewho is recognized for his future promise as well as his prior accomplishments, Dr. Drexler has noshortage of ideas for enhancing OCT's value as a clinical and research tool. Dr. Drexler, professor ofbiomedical engineering at Cardiff University, Wales, received the Cogan Award Tuesday night.

Through multidisciplinary research collaborations across a wide range of discipline, Dr. Drexlerhopes to develop in vivo three-dimensional subcellular, molecular, and functional imaging technologyof significant diagnostic value. He compared OCT with MRI and CT technology, once novel approachesnow widely used for numerous diagnostic purposes.

Over the years, the fundamental technological parameters of OCT have been strengthened, with Dr.Drexler playing a key role. Axial resolution, acquisition speed, penetration, and transverseresolution are among the parameters that have significantly improved and enhanced the application ofOCT in ophthalmology as well as other specialties.

Describing the growing acceptance of OCT since it first appeared in the early 1990s, Dr. Drexlernoted that it has passed benchmarks in the cycle of new technology such as skepticism.

"We've passed acceptance and we're between elation and state of the art," he said. Disillusion oftenfollows state of the art as the drawbacks of new devices become known, but the level of activity atDr. Drexler's lab and in his collaborations with others in shows no sign of that.

Dr. Drexler and his colleagues are working on concepts such as three-dimensional, adaptive optics,ultra high-resolution OCT that could be applied to cellular resolution retinal imaging, as well asin vivo spectroscopic OCT and optophysiology. Optophysiology is a form of noninvasive, depth-resolveddetection of retinal physiology. He also suggested that OCT could be used to perform virtualsurgery.

OCT began as a tool for optical biopsy and has drawn the attention of researchers, clinicians,manufacturers, and investors, but it will not necessarily supersede other technologies, Dr. Drexlersaid.

"I personally think that OCT will never replace any gold standard like histology or establishedimaging modalities, but it will be very important at generating information in the future," Dr.Drexler said. "It provides you with more information for earlier diagnosis."

He predicted that noninvasive monitoring of diseases and of the effectiveness of new drugs will beimportant roles for OCT, as will the study of biology.