News Story

by Cat Vasko

· Oral Contrast for GI Imaging Gains Ground
· Siemens Launches New PEV Tool for CT Colonography
· CME Courses for Breast MRI CAD
· GE Healthcare Ranks first for CT and MR

Oral Contrast for GI Imaging Gains Ground

In August 2004, E-Z-EM Inc, Lake Success, NY, introduced its new VoLumen oral contrast for gastrointestinal (GI) imaging. VoLumen was inspired by negative neutral contrasts designed for MR enterography; its makeup is similar to a positive contrast manufactured by E-Z-EM, but it contains only a tenth of the barium. After a couple of years on the market, VoLumen is now seeing a major increase in usage, primarily from gastroenterologists using it to image patients with Crohn’s syndrome. But what brought about the sea change?

“What’s been used for the last 30 years is positive oral contrast, either iodine or a dilute barium in the range of 2% to 5%,” explained Roy Watson, product manager at E-Z-EM. “GI radiologists are familiar with this kind of contrast. They’re used to it, and one advantage is that if there’s an extravasation they can easily identify it. But some disadvantages are that it can create artifacts in a 3D or volumetric environment. It also impairs true wall evaluation.”

VoLumen helps to better visualize small sinus tracts along the mesenteric border in a patient with Crohn’s.

So manufacturers like E-Z-EM went hunting for a negative oral contrast that would still allow for the identification of extravasations. But patients poorly tolerated some initial attempts, including contrasts based on methylcellulose. Others, like agents made with polyethylene glycol, proved equally unsuitable.

VoLumen contains locust bean gum and 0.1% barium to provide a slightly elevated Hounsfield unit level. “The barium helps with the identification of fistula, specifically,” Watson said. “VoLumen’s been used for many different applications, but probably the biggest is Crohn’s.”

According to criteria developed by the American College of Radiology (ACR), Reston, Va, neutral contrast is the most appropriate agent for CT enterography. “The ACR also says it’s no longer okay to just say it’s Crohn’s,” Watson noted. “You need to know if it’s active or chronic.”

In the past year, 24 studies on VoLumen have come out. The first paper to evaluate its efficacy when compared with other contrasts came from the Mayo Clinic, Rochester, Minn, which “showed in over 700 patients that VoLumen was the preferred method for CT enterography, and that CT enterography is replacing the small bowel exam in fluoro,” Watson said. “They’re very complementary exams. We’ll never be able to get the wall visualization the capsule does, but the two combined are a very powerful test for patients with Crohn’s.”

VoLumen’s popularity is spreading to other procedures and modalities. A recent paper from Massachusetts General Hospital, Boston, demonstrates the contrast’s usefulness in PET/CT imaging, where positive oral contrast can cause artifacts. “We also see what we call indication drift from the GEs, where they start to use it here or there, try it in new applications,” Watson said. “And we’ve seen its use expand in the ER as well, because it has a very rapid transit compared to positive contrast agent, and a much lower viscosity.”

—Cat Vasko

CME Courses for Breast MRI CAD

Constance Lehman, MD, director of breast imaging at University of Washington School of Medicine and Seattle Cancer Care Alliance.

The International Center for Postgraduate Medical Education (ICPME), Ithaca, NY, recently received an educational grant from Confirma Inc, Bellevue, Wash, to develop a new curriculum of continuing medical education (CME) for breast MRI computer-aided detection (CAD). The curriculum includes two free programs: a series of online case reviews using CAD to aid the radiologist in the analysis and interpretation of breast MRI studies, and a series of full-day courses including instruction and hands-on training in breast MR imaging, interpretation, and intervention.

“We’ve collaborated with ICPME and course faculty to ensure the program is as current in content as possible,” said Meghan Mitchell, marketing manager at Confirma. The company supports ICPME with an educational grant for these programs. “Curriculum at the hands-on training includes a review of research and guidelines, MR equipment and protocols, acquisition techniques, methods for analysis and the use of CAD, and intervention.”

The online seminars are succinct 1-hour case reviews; the day-long courses are more comprehensive. “We realize how valuable hands-on experience is in education and training,” Mitchell noted. “A good portion of the course, about 2 hours, is dedicated to attendees gaining hands-on experience interpreting cases with CAD. The latter portion of the course will be focused on biopsy technique with more hands-on time.”

The first all-day course takes place in Littleton, Colo, on October 11; there will be two additional courses, one in Los Angeles on January 17 and another in Dallas on February 1. The next online case review is scheduled for September 25.

Though the curriculum is more physician-focused, Mitchell estimates that about 30% of participants are technologists. “We intend to support ICPME and develop a curriculum exclusively for the technologists, and offer online and hands-on courses as well,” she noted. “With extensive research being published, there is a real need in the community for comprehensive education programs offering guidance on performing this valuable study with increased efficiency, standardization, and quality.”

To develop faculty for the case reviews and courses, ICPME turned to Constance Lehman, MD, director of breast imaging at University of Washington School of Medicine and Seattle Cancer Care Alliance. “Dr Lehman is a prominent researcher and physician in breast MRI, is on the ACS [American Cancer Society] panel that released the guidelines on breast cancer detection for high-risk screening, and is on the board for ACR BI-RADS,” Mitchell said. Lehman was then tasked with recruiting faculty for the program, and is herself one of the instructors for the all-day course.

“There are challenges associated with breast MRI and thus adequate training is essential,” noted David Gruen, MD, medical director of The Suite for Women’s Imaging, Norwalk, Conn, and a member of the online case review faculty. “ICPME’s new programs will enable radiologists to become more proficient and help meet the increasing demand for this important procedure.”

—C. Vasko