Researchers take optical coherence tomography to the next level: With clearer imaging and improved resolution, a new OCT approach could improve medical diagnostic imaging

Researchers have developed an improved version of optical coherence tomography (OCT) that can image biomedical samples with higher contrast and resolution over a wider 3D field of view than before. The new 3D microscope could be useful for biomedical research and possibly enable more accurate medical diagnostic imaging.

In Optical, Optica Publishing Group’s journal for high-impact research, Duke University researchers describe the new technique, which they call 3D optical coherence tomography refraction (3D OCRT). Using various biological samples, they show that 3D OCRT produces highly detailed images that reveal features that are difficult to observe with traditional OCT.

OCT uses light to provide high resolution 3D images without the need for contrast agents or labels. Although commonly used for applications in ophthalmology, the imaging method can also be used to image many other parts of the body such as the skin and the inside of the ears, mouth, arteries and tract. gastrointestinal.

“OCT is a volumetric imaging technique widely used in ophthalmology and other branches of medicine,” said first author Kevin C. Zhou. “We have developed an exciting new extension, featuring new hardware combined with a new computer algorithm for 3D image reconstruction to address some well-known limitations in imaging technique.”

“We envision this approach being applied in a wide variety of biomedical imaging applications, such as live diagnostic imaging of the human eye or skin,” said Joseph A. Izatt, co-leader of the research team. “The hardware we designed to perform the technique can also be easily miniaturized into small probes or endoscopes to access the gastrointestinal tract and other parts of the digestive system. body.”

See more with OCT

Although OCT has proven useful in both clinical applications and biomedical research, it is difficult to acquire high resolution OCT images over a wide field of view in all directions simultaneously due to the fundamental limitations imposed by propagation of the optical beam. Another challenge is that OCT images contain high levels of random noise, called speckle, which can obscure important biomedical details.

To overcome these limitations, the researchers used an optical design incorporating a parabolic mirror. This type of mirror is commonly found in non-imaging applications, such as flashlights, where it surrounds the bulb to direct light in one direction. The researchers used an optical setup in which light was sent the other way, with the sample placed where a flashlight bulb would be.

This design allowed the sample to be imaged from multiple views over a very wide range of angles. They developed a sophisticated algorithm to combine the views into a single high-quality 3D image that corrects distortions, noise and other imperfections.

“The work published in Optical expands on our previous research by overcoming significant engineering challenges, both in hardware and software, to enable OCRT to work in 3D and make it more widely applicable,” said Sina Farsiu , co-leader of the research team. “Because our system generates tens to hundreds of gigabytes of data, we had to develop a new algorithm based on modern computational tools that have recently matured within the machine learning community.”

Get a wider view

The researchers demonstrated the versatility and wide applicability of the method by using it to image various biological samples, including a zebrafish and a fruit fly, which are important model organisms for behavioral, developmental and neurobiological studies. They also imaged mouse tissue samples from the trachea and esophagus to demonstrate the potential for medical diagnostic imaging. With 3D OCRT, they acquired 3D fields of view up to ±75° without moving the sample.

“In addition to reducing noise artifacts and correcting sample-induced distortions, OCRT is inherently capable of computer-creating contrast from tissue properties that are less visible in traditional OCT,” said Zhou said. “For example, we show that it is sensitive to oriented structures such as fiber-like tissues.”

Researchers are now exploring ways to make the system smaller and faster for live imaging by taking advantage of recent developments in faster OCT system technologies and advances in deep learning that can speed up or improve data processing.

Source of the story:

Materials provided by Optical. Note: Content may be edited for style and length.

#Researchers #optical #coherence #tomography #level #clearer #imaging #improved #resolution #OCT #approach #improve #medical #diagnostic #imaging

Leave a Comment

Your email address will not be published. Required fields are marked *