Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New microscope uses rainbow of light to image the flow of individual blood cells

22.05.2012
Non-invasive test promises rapid, pain-free diagnoses without the use of fluorescent dyes

Blood tests convey vital medical information, but the sight of a needle often causes anxiety and results take time. A new device developed by a team of researchers in Israel, however, can reveal much the same information as a traditional blood test in real-time, simply by shining a light through the skin. This optical instrument, no bigger than a breadbox, is able to provide high-resolution images of blood coursing through our veins without the need for harsh and short-lived fluorescent dyes.


The team’s device relies on a technique called spectrally encoded confocal microscopy. (a) A single line within a blood vessel is imaged with multiple colors of light that encode lateral positions. (b) A single cell crossing the spectral line produces a two-dimensional image with one axis encoded by wavelength and the other by time. Credit: Biomedical Optics Express


An in vivo image shows red blood cells within a microvessel. The area occupied by red blood cells in the images can be used to calculate the percent volume of red blood cells, a key measurement for many medical diagnoses. Credit: Biomedical Optics Express

"We have invented a new optical microscope that can see individual blood cells as they flow inside our body," says Lior Golan, a graduate student in the biomedical engineering department at the Israel Institute of Technology, or Technion, and one of the authors on a paper describing the device that is published today in the Optical Society's (OSA) open-access journal Biomedical Optics Express. By eliminating a long wait-time for blood test results, the new microscope might help spotlight warning signs, like high white blood cell count, before a patient develops severe medical problems. The portability of the device could also enable doctors in rural areas without easy access to medical labs to screen large populations for common blood disorders, Golan notes.

Using the new microscope, the researchers imaged the blood flowing through a vessel in the lower lip of a volunteer. They successfully measured the average diameter of the red and white blood cells and also calculated the percent volume of the different cell types, a key measurement for many medical diagnoses.

The device relies on a technique called spectrally encoded confocal microscopy (SECM), which creates images by splitting a light beam into its constituent colors. The colors are spread out in a line from red to violet. To scan blood cells in motion, a probe is pressed against the skin of a patient and the rainbow-like line of light is directed across a blood vessel near the surface of the skin. As blood cells cross the line they scatter light, which is collected and analyzed. The color of the scattered light carries spatial information, and computer programs interpret the signal over time to create 2-D images of the blood cells.

Currently, other blood-scanning systems with cellular resolution do exist, but they are far less practical, relying on bulky equipment or potentially harmful fluorescent dyes that must be injected into the bloodstream.

"An important feature of the technique is its reliance on reflected light from the flowing cells to form their images, thus avoiding the use of fluorescent dyes that could be toxic," Golan says. "Since the blood cells are in constant motion, their appearance is distinctively different from the static tissue surrounding them." The team's technique also takes advantage of the one-way flow of cells to create a compact probe that can quickly image large numbers of cells while remaining stationary against the skin.

At first, the narrow field of view of the microscope made it difficult for the team to locate suitable capillary vessels to image. To solve this, the researchers added a green LED and camera to the system to provide a wider view in which the blood vessels appeared dark because hemoglobin absorbs green light. "Unfortunately, the green channel does not help in finding the depth of the blood vessel," notes Golan. "Adjusting the imaging depth of the probe for imaging a small capillary is still a challenge we will address in future research."

The researchers are also working on a second generation system with higher penetration depth.

The new system might expand the range of possible imaging sites beyond the inside lip, which was selected as a test site since it was rich in blood vessels, has no pigment to block light, and doesn't lose blood flow in trauma patients.
Additional steps include work to miniaturize the system for ease of transport and use. "Currently, the probe is a bench-top laboratory version about the size of a small shoebox," says Golan. "We hope to have a thumb-size prototype within the next year."

Paper: "Noninvasive imaging of flowing blood cells using label-free spectrally encoded flow cytometry," Golan et al., Biomedical Optics Express, Vol. 3, Issue 6, pp. 1455-1464 (2012). http://www.opticsinfobase.org/boe/abstract.cfm?uri=boe-3-6-1455
EDITOR'S NOTE: High-resolution images are available to members of the media upon request. Contact Angela Stark, astark@osa.org.

About Biomedical Optics Express
Biomedical Optics Express is OSA's principal outlet for serving the biomedical optics community with rapid, open-access, peer-reviewed papers related to optics, photonics and imaging in the life sciences. The journal scope encompasses theoretical modeling and simulations, technology development, and biomedical studies and clinical applications. It is published by the Optical Society and edited by Joseph A. Izatt of Duke University. Biomedical Optics Express is an open-access journal and is available at no cost to readers online at http://www.OpticsInfoBase.org/BOE.

About OSA

Uniting more than 130,000 professionals from 175 countries, the Optical Society (OSA) brings together the global optics community through its programs and initiatives. Since 1916 OSA has worked to advance the common interests of the field, providing educational resources to the scientists, engineers and business leaders who work in the field by promoting the science of light and the advanced technologies made possible by optics and photonics. OSA publications, events, technical groups and programs foster optics knowledge and scientific collaboration among all those with an interest in optics and photonics.

Angela Stark | EurekAlert!
Further information:
http://www.osa.org

More articles from Medical Engineering:

nachricht PET identifies which prostate cancer patients can benefit from salvage radiation treatment
05.12.2017 | Society of Nuclear Medicine and Molecular Imaging

nachricht Designing a golden nanopill
01.12.2017 | University of Texas at Austin, Texas Advanced Computing Center

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>