Features | Partner Sites | Information | LinkXpress
Sign In
Samsung
Schiller
ElsMed

Near Infrared-2 Imaging Technology Developed for Visualizing Blood Flow

By Medimaging International staff writers
Posted on 26 Dec 2012
Image: These images of a mouse's blood vessels show the difference in resolution between traditional near-infrared fluorescence imaging (top) and Stanford's new NIR-2 technique (bottom) (Photo courtesy of Stanford University).
Image: These images of a mouse's blood vessels show the difference in resolution between traditional near-infrared fluorescence imaging (top) and Stanford's new NIR-2 technique (bottom) (Photo courtesy of Stanford University).
Investigators have developed a fluorescence imaging technique that provides a view of the pulsing blood vessels of living animals with never-before-seen clarity. Compared with traditional imaging technologies, the sharpness enhancement is similar to cleaning fog off eyeglasses.

The technique, called near infrared-2 imaging (NIR-2), involves first injecting water-soluble carbon nanotubes into the live subject’s bloodstream. The researchers then shine a laser (its light is in the near-infrared range, a wavelength of about 0.8 micrometers) over the subject—in this instance, a mouse. The light causes the specially engineered nanotubes to fluoresce at a longer wavelength of 1-1.4 micrometers, which is then detected to determine the blood vessels’ structure.

That the nanotubes fluoresce at considerably longer wavelengths than conventional imaging techniques is vital in achieving the amazingly sharp images of the tiny blood vessels: longer wavelength light scatters less, and thereby generates clearer images of the vessels. Another advantage of detecting such long wavelength light is that the detector registers less background noise since the body does not produce autofluorescence in this wavelength range.

In addition to providing fine details, the technique, developed by Stanford University (Stanford, CA, USA) scientists Hongjie Dai, PhD, professor of chemistry; John Cooke, MD, PhD, professor of cardiovascular medicine; and Ngan Huang, PhD, acting assistant professor of cardiothoracic surgery—has a fast image acquisition rate, allowing researchers to measure blood flow in near real time.

The research was published online November 18, 2012, in the journal Nature Medicine. The ability to obtain both blood flow data and blood vessel clarity was not earlier possible, and will be especially useful in studying animal models of arterial disease, such as how blood flow is affected by the arterial blockages and constrictions that cause, among other things, heart attacks and stroke. “For medical research, it’s a very nice tool for looking at features in small animals,” Prof. Dai said. “It will help us better understand some vasculature diseases and how they respond to therapy, and how we might devise better treatments.”

Because NIR-2 can only penetrate 1 cm, at most, into the body, it will not replace other imaging techniques for humans, but it will be a powerful method for studying animal models by replacing or complementing computed tomography (CT), X-ray, magnetic resonance imaging (MRI), and laser Doppler techniques.

The next phase of the research, and one that will make the technology more easily accepted for use in humans, is to study alternative fluorescent molecules, according to Prof. Dai. “We’d like to find something smaller than the carbon nanotubes but that emit light at the same long wavelength, so that they can be easily excreted from the body and we can eliminate any toxicity concerns.”

Related Links:

Stanford University



PHS Technologies
Supersonic Imagine
ARAB HEALTH

Channels

Radiography

view channel
Image: Coronary CT angiography images demonstrate examples of high-risk plaque features. A, Image was obtained in a 63-year-old man with partially calcified plaque, positive remodeling (vertical arrow), and spotty calcium (horizontal arrow). B, A cross-sectional view of a noncalcified plaque in a 65-year-old man demonstrates a napkin-ring sign with a central low-attenuation area, surrounded by a peripheral rim of higher attenuation (arrow) next to the lumen (∗). C, Image in a 60-year-old woman with partially calcified plaque demonstrates a low CT number in the midportion (arrow) (Photo courtesy of the journal Radiology).

Coronary CT Angiography Reveals Link between Coronary Artery Plaque and Liver Disease

Researchers using coronary computed tomography angiography (CCTA) imaging have found a close correlation between high-risk coronary artery plaque and a common liver disease. The research revealed that... Read more

Nuclear medicine

view channel
Image: The RayPilot placed directly on the original carbon fiber couch (Photo courtesy of Micropos Medical).

Hypofractionated Prostate Radiotherapy Electromagnetic Positioning Tool Tracks Tumors in Real Time During Treatment

A new add-on tool to existing radiotherapy equipment has been designed to track a tumor at any time during the treatment. The system could enable the clinic to enhance precision in their cancer treatment,... Read more

Imaging IT

view channel

Use of Radiology Data Mining Tool Reduces Length of Stay for CT Biopsy

Use of a data and analysis tool allows radiology clinical coordinators to facilitate a patient-centered imaging service, acting as a care manager for patients with positive findings on their computed tomography (CT) scans. Syed F. Zaidi, MD, president of Radiology Associates of Canton (RAC; OH, USA) and chief executive... Read more

Industry News

view channel
Image: Zygote’s human anatomy collections (Photo courtesy of Zygote).

Partnership to Provide 3-D Holographic Imaging to Medical Professionals

Zebra Imaging, Inc. (Austin, TX, USA), a provider of three-dimensional (3-D) holographic visualization technologies, reported on a partnership with the Zygote Media Group, Inc. (American Fork, UT, USA),... Read more
 

Events

01 Dec 2014 - 05 Dec 2014
11 Jan 2015 - 14 Jan 2015
Copyright © 2000-2014 Globetech Media. All rights reserved.