Navigation Links
A better imager for identifying tumors

WASHINGTON, June 19, 2014Before they excise a tumor, surgeons need to determine exactly where the cancerous cells lie. Now, research published today 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 systemsnear-infrared fluorescent imaging to detect marked cancer cells and visible light reflectance imaging to see the contours of the tissue itselfinto 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.


Contact: Lyndsay Meyer
The Optical Society

Related medicine news :

1. Kids with strong bonds to parents make better friends, can adapt in relationships
2. Kids whose time is less structured are better able to meet their own goals
3. Researchers create better methods to detect E. coli
4. Chemical strategy hints at better drugs for osteoporosis, diabetes
5. Cryoprobes better than traditional forceps for obtaining certain lung biopsies
6. Bloodstream infections reduced through better central line care at three hospitals
7. Brain signals link physical fitness to better language skills in kids
8. A tool to better screen and treat aneurysm patients
9. Funding for better understanding of cancer-causing cell defect
10. Game changer: Patients of doctors who played online game had better control of blood pressure
11. Children who exercise have better body-fat distribution, regardless of their weight
Post Your Comments:
Related Image:
A better imager for identifying tumors
(Date:11/25/2015)... ... November 25, 2015 , ... For the first time, Vitalalert is donating ... Beat ” campaign. The partnership between the two groups began in 2014 with Vitalalert ... cause. , MAP International was founded in 1954 and is an international Christian-based health ...
(Date:11/25/2015)... ... 2015 , ... Dental professionals who would like to become more proficient on ... Dr. Mark Iacobelli’s Advanced Implant Mentoring (AIM) CE course. Courses will be held on ... co-founders of Advanced Implant Mentoring (AIM), Dr. Iacobelli and Dr. D’Orazio are proud to ...
(Date:11/25/2015)... ... 2015 , ... The McHenry County law firm of Botto Gilbert Lancaster, ... Francisco J. Botto and Alex C. Wimmer. Attorneys Botto and Wimmer represented the claimant ... (2d) 130884WC. , According to court documents, Adcock testified that on May 10, 2010 ...
(Date:11/25/2015)... ... November 25, 2015 , ... SCOTTSDALE, ... facial plastic surgeon specializing in both surgical and non-surgical treatments, announced the expansion ... at Hobgood Facial Plastic Surgery. , Highly trained and nationally recognized for ...
(Date:11/25/2015)... ... 25, 2015 , ... In an ongoing Clinical Study conducted by an independent ... UV Angel is evaluating the efficacy of its product and its disinfection protocol. This ... beds) from May 2014 through October 2015 at a 360-bed, acute-care, academic medical center ...
Breaking Medicine News(10 mins):
(Date:11/26/2015)... , 26 november 2015 ... kondigt de geplande investering aan van ten ... de laboratoria en het mondiale hoofdkantoor in ... uitbreiding zal resulteren in extra kantoorruimte en ... aan de groeiende behoeften van de farmaceutische ...
(Date:11/26/2015)... , November 26, 2015 ... A new combination approach blends immunotherapy with Bremachlorin-photodynamic therapy ... new combination approach blends immunotherapy with Bremachlorin-photodynamic therapy for ... new combination approach blends immunotherapy with Bremachlorin-photodynamic therapy for ... has found that immunotherapy can be efficiently ...
(Date:11/26/2015)... 26, 2015 ... aanpak combineert immunotherapie met Bremachlorin-photodynamische therapie voor ... ) --> ... ) Uit ... Centrum (LUMC) blijkt ...
Breaking Medicine Technology: