CR vendors prepare blitz into U.S. mammography market

October 10, 2005

Computed radiographic mammography, although widely available in Europe and Asia, is only now coming to the U.S. market, as major manufacturers hope to win FDA approval for their devices in the coming months, weeks, even days.

Computed radiographic mammography, although widely available in Europe and Asia, is only now coming to the U.S. market, as major manufacturers hope to win FDA approval for their devices in the coming months, weeks, even days.

Fujifilm Medical Systems USA has been selling its CR mammography (FCRm) solution around the world for the last 18 months and has more than 1000 units installed outside the U.S. In March, the company turned in the final module of its premarket approval submission. Company executives hope to receive approval of the CR mammography product any day now, according to Andy Vandergrift, national program manager for Women's Healthcare Imaging Systems at Fuji.

The game plan for bringing FCRm to market will focus on Fuji's installed base of general radiography CR systems.

"We have been selling CR in the U.S. for more than 20 years. We have a customer base built up that uses our Synapse PACS product, and mammography is the only area where they are doing screen-film imaging. So they will be an obvious target for us," Vandergrift said. "Other PACS facilities have a processor in mammography and are looking to take mammography digital. Facilities that have a digital mindset and want to round out their digital processing capabilities would be another obvious target for us."

Konica Minolta Medical Imaging USA released in February its phase-contrast mammography (PCM) system in Japan. It will launch the same system worldwide at the RSNA meeting in November. Konica Minolta is currently conducting clinical studies of the system prior to submitting its PMA, said Eunice Lin, marketing and product planning manager.

Kodak has been marketing in Europe, Latin America, and Asia an upgrade that supports mammography to its DirectView CR 850, 950, and 975 systems. The company is in the process of performing clinical trials as part of the FDA approval process for the U.S. and Canada, said Jeff Byng, a specialist in imaging science and technology for the Kodak Health Group.

If and when these products appear in the U.S., they will not be the first CR mammography products there. Fuji began marketing CR technology for mammography in 1983 but voluntarily removed those products from the market in the mid-1990s, when the FDA changed its position on digital mammography and required PMA review, according to Vandergrift.

Rather than take its first-generation CR product through the PMA process, Fuji decided to wait until the current system came through the pipeline. The FCRm solution offers improved performance compared with the product initially developed by Fuji for the U.S. market. Resolution is 50 microns compared with 100 microns, and data are captured on the front and back of the imaging plate rather than just one side. Dual-side imaging increases detective quantum efficiency by 70% and reduces image noise by as much as 50%, he said.

Its path through the FDA has been anything but easy. Fuji submitted the first module of the PMA submission in July 2003. Vandergrift suspects that the FDA has put off approval and continued to request additional information about the product since then because CR is the first cassette-based digital approach to mammography.

"We are breaking new ground with the FDA, and the length of review may be because our technology is so different from those that were approved in the past," he said.

The companies that are bringing CR mammography to the U.S. marketplace are following one of two principal technologic strategies. Fuji and Kodak are developing systems that can be used with existing mammography equipment as well as with general radiography.

The Fuji FCRm solution replaces an existing screen-film cassette with a cassette that includes an imaging plate, which is processed by the same CR reader already in use for other radiography exams. Once the image reader processes the information, it is presented on a PC, where the technologist performs quality control and makes the images available for reading by the radiologist.

Kodak's DirectView CR Mammography system retains all the features of its general radiography systems and image processing. To enhance image quality for mammography, the DirectView upgrade produces scans with a 50-micron pixel pitch. A new EHR-M screen enhances detective quantum efficiency to improve signal-to-noise performance.

DirectView cassettes are compatible with mammography x-ray machines and automatic exposure control. Designed for mammography, the cassettes allow image capture close to the chest wall.

Konica Minolta has taken a different tack with the Regius PureView Mammography System, which combines phase-contrast mammography with CR. Phase-contrast technology enhances the edge effects from x-ray refraction to increase the sharpness of contrast at the edges of the breast as well as the architecture of microcalcifications and fibrils within the breast, according to the company.

To overcome blurriness, which is common with phase-contrast imaging, the Regius PureView system uses a molybdenum x-ray tube with a 100-micron focal spot. It selects the optimal combination of x-ray focal spot size, distance between the x-ray source and the object, distance between the source and the detector, and sampling pitch of the CR reader.

Images captured through the mammography system are scanned by Konica's Xpress CR reader at 43.75 microns, which produces a resolution of 20 line pairs per millimeter, and can be sent to a dry printer for hard-copy reading or to a PACS workstation for soft-copy review.

Because of the intricacies of design of the Regius PureView mammography system, it cannot be added as a field upgrade. It is intended strictly for mammography, not for general radiography.

"We believe this is breakthrough technology that makes phase-contrast mammography clinically and commercially viable. At the same time, the cost will be competitive and affordable," Lin said.

Regardless of technological differences, CR manufacturers believe the U.S. mammography market is anxiously awaiting the release of their products, particularly now that the authors of the Digital Mammographic Imaging Screening Trial (DMIST) have demonstrated the clinical superiority of digital mammography for imaging women at high risk for breast cancer (DI SCAN 9/26/05) and facilities familiar with CR have seen the workflow efficiencies digital technology can provide.

"In terms of CR, the belief is that it is a cost-effective way of bringing some of the advantages of digital technology to the sharing, processing, and manipulation of images," Byng said.