Featured Research

from universities, journals, and other organizations

Better imager for identifying tumors

Date:
June 19, 2014
Source:
The Optical Society
Summary:
A new technique that could improve surgeons' ability to identify cancerous tumors and remove them in real-time in the operating room has been developed by researchers. The new imaging system combines two techniques -- near-IR fluorescent imaging and visible light reflectance imaging -- to get a much better picture of the tissue.

Near-infrared (left) and visible (right) images of the aperture filter, used in the new dual-mode imager. Only the central region of the filter can transmit visible light, while the outer portion can only transmit the near-infrared light used for fluorescent imaging.
Credit: Optics Letters

Before they excise a tumor, surgeons need to determine exactly where the cancerous cells lie. Now, research published in The Optical Society's (OSA) journal Optics Letters details a new technique that could give surgeons cheaper and more lightweight tools, such as goggles or hand-held devices, to identify tumors in real time in the operating room.

The new technology, developed by a team at the University of Arizona and Washington University in St. Louis, is a dual-mode imager that combines two systems -- near-infrared fluorescent imaging to detect marked cancer cells and visible light reflectance imaging to see the contours of the tissue itself -- into one small, lightweight package approximately the size of a quarter in diameter, just 25 millimeters across.

"Dual modality is the path forward because it has significant advantages over single modality," says author Rongguang Liang, associate professor of optical sciences at the University of Arizona.

Interest in multi-modal imaging technology has surged over the last 10 years, says Optics Letters topical editor Brian Applegate of Texas A&M University, who was not involved in the research. People have realized that in order to better diagnose diseases like cancer, he says, you need information from a variety of sources, whether it's fluorescence imaging, optical imaging or biochemical markers.

"By combining different modalities together, you get a much better picture of the tissue," which could help surgeons make sure they remove every last bit of the tumor and as small amount of healthy tissue as possible, Applegate says.

Currently, doctors can inject fluorescent dyes into a patient to help them pinpoint cancer cells. The dyes converge onto the diseased cells, and when doctors shine a light of a particular wavelength onto the cancerous area, the dye glows. In the case of a common dye called indocyanine green (ICG), it glows in near-infrared light. But because the human eye isn't sensitive to near-infrared light, surgeons have to use a special camera to see the glow and identify the tumor's precise location.

Surgeons also need to be able to see the surface of the tissue and the tumor underneath before cutting away, which requires visible light imaging. So researchers have been developing systems that can see in both fluorescent and visible light modes.

The trouble is that the two modes have opposing needs, which makes integration difficult. Because the fluorescent glow tends to be dim, a near-infrared light camera needs to have a wide aperture to collect as much fluorescent light as possible. But a camera with a large aperture has a low depth of field, which is the opposite of what's needed for visible-light imaging.

"The other solution is to put two different imaging systems together side by side," Liang says. "But that makes the device bulky, heavy and not easy to use."

To solve this problem, Liang's group and that of his colleagues, Samuel Achilefua and Viktor Gruev at Washington University in St. Louis, created the first-of-its-kind dual-mode imaging system that doesn't make any sacrifices.

The new system relies on a simple aperture filter that consists of a disk-shaped region in the middle and a ring-shaped area on the outside. The middle area lets in visible and near-infrared light but the outer ring only permits near-infrared light. When you place the filter in the imaging system, the aperture is wide enough to let in plenty of near-infrared light. But since visible light can't penetrate the outer ring, the visible-sensitive part of the filter has a small enough aperture that the depth of field is large.

Liang's team is now adapting its filter design for use in lightweight goggle-like devices that a surgeon can wear while operating. They are also developing a similar hand-held instrument.


Story Source:

The above story is based on materials provided by The Optical Society. Note: Materials may be edited for content and length.


Cite This Page:

The Optical Society. "Better imager for identifying tumors." ScienceDaily. ScienceDaily, 19 June 2014. <www.sciencedaily.com/releases/2014/06/140619154109.htm>.
The Optical Society. (2014, June 19). Better imager for identifying tumors. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2014/06/140619154109.htm
The Optical Society. "Better imager for identifying tumors." ScienceDaily. www.sciencedaily.com/releases/2014/06/140619154109.htm (accessed July 23, 2014).

Share This




More Matter & Energy News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Robot Parking Valet Creates Stress-Free Travel

Robot Parking Valet Creates Stress-Free Travel

AP (July 23, 2014) 'Ray' the robotic parking valet at Dusseldorf Airport in Germany lets travelers to avoid the hassle of finding a parking spot before heading to the check-in desk. (July 23) Video provided by AP
Powered by NewsLook.com
Boeing Ups Outlook on 52% Profit Jump

Boeing Ups Outlook on 52% Profit Jump

Reuters - Business Video Online (July 23, 2014) Commercial aircraft deliveries rose seven percent at Boeing, prompting the aerospace company to boost full-year profit guidance- though quarterly revenues missed analyst estimates. Bobbi Rebell reports. Video provided by Reuters
Powered by NewsLook.com
Europe's Car Market on the Rebound?

Europe's Car Market on the Rebound?

Reuters - Business Video Online (July 23, 2014) Daimler kicks off a round of second-quarter earnings results from Europe's top carmakers with a healthy set of numbers - prompting hopes that stronger sales in Europe will counter weakness in emerging markets. Hayley Platt reports. Video provided by Reuters
Powered by NewsLook.com
9/11 Commission Members Warn of Terror "fatigue" Among American Public

9/11 Commission Members Warn of Terror "fatigue" Among American Public

Reuters - US Online Video (July 22, 2014) Ten years after releasing its initial report, members of the 9/11 Commission warn of the "waning sense of urgency" in combating terrorists attacks. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins