GE Medical Systems begins European shipments of Senographe 2000D digital mammography unit

Company joins Trex Medical as only firms with approval

GE Medical Systems has begun European shipments of its Senographe 2000D full-field digital mammography system, the company announced at last week’s European Congress of Radiology in Vienna. Senographe 2000D has received the CE Mark, and the first commercial unit was installed at Charite Hospital in Berlin in late February.

GE joins Trex Medical as one of only two companies able to market a full-field digital mammography system anywhere in the world. The fact that these systems are available in Europe before the U.S. highlights the difficulties manufacturers have faced in getting full-field systems approved by the Food and Drug Administration.

GE announced the commercialization at a news conference on March 8. GE has made major investments in digital technology over the last several years, through both acquisition and internal development, according to Larry Johnston, president and CEO of the company’s GE Medical Systems Europe subsidiary in Buc, France.

Senographe 2000D’s digital detector is based on amorphous silicon flat-panel detectors manufactured in the company’s plant in Santa Clara, CA, a joint venture between GE and EG&G Amorphous Silicon. The detectors are then shipped to France, where they are incorporated into Senographe systems built at the company’s x-ray and mammography factory in Buc.

GE plans to sell Senographe 2000D both as a new system and as an upgrade to premium Senographe DMR systems and mid-range Senographe 800T systems in the field, according to Sonia Dubreuil, manager of GE’s global mammography business.

In the ECR press conference, Dubreuil and other GE executives enumerated the advantages of digital technology for mammography applications. Digital mammography has better contrast resolution and better dynamic range than film, and it allows the use of image postprocessing techniques. The company has developed its own dedicated mammography archive for facilities that want a digital storage option but that haven’t yet moved into PACS.

Digital mammography will also support advanced clinical applications under development such as computer-aided diagnosis. GE has an agreement with R2 Technology of Los Altos, CA, to provide R2’s ImageChecker CAD workstations in conjunction with Senographe 2000D. The companies are working on integrating the two systems and hope to be able to offer a complete package early next year. R2 is already selling ImageChecker in Europe for digitized mammography film.

Although the advantages of digital mammography are clear, some prospective customers may balk at the high price of the systems. Senographe 2000D units will carry a list price between $400,000 and $500,000. That’s much higher than a standard analog Senographe DMR, which sells in the $60,000 to $85,000 price range.

GE believes that the advantages of digital mammography will win many buyers over. The higher throughput of digital systems will help offset their higher cost. In addition, some countries, like France, reimburse at slightly higher rates for digital procedures than for analog exams.

On the competitive front, GE will also have to contend with Trex Medical for digital mammography sales. Trex Digital Mammography System (TDMS) was awarded the CE Mark in October (SCAN 10/14/98). The first commercial TDMS unit is scheduled to be installed later this month at a hospital in Bern, Switzerland, according to Lim Cheung, vice president of R&D at Trex’s Bennett division in Copiague, NY.

Although Trex lacks the market power and name recognition of GE in Europe, the company does appear to have an edge on the technical side. TDMS, which is based on CCD detectors rather than amorphous silicon, has image resolution of 12.5 line pairs/mm with a 40-micron pixel size. GE’s amorphous silicon detectors have a resolution of 5 line pairs/mm with a 100-micron pixel size. Both firms claim that their detectors have detective quantum efficiency (DQE) ratings in the 60% range.

GE, however, claims that its use of amorphous silicon has distinct advantages over technologies like CCDs. GE’s detectors are made of a large single thin-film transistor panel, and thus do not require image tiling to stitch together images from multiple detector elements.

Although European patients will soon begin to experience the benefits of full-field digital mammography, it’s still unclear when these systems will be available in the U.S. GE, Trex, and Fischer Imaging of Denver are vying to be the first companies to win FDA clearance. The FDA has made matters difficult, however, by repeatedly changing the guidelines under which companies should conduct clinical trials to support their 510(k) submissions. The FDA has promised that a new set of guidelines is forthcoming, but industry has been waiting over half a year for its release.

Trex had its 510(k) application for TDMS bounced back by the FDA in December, with the agency requesting additional data to support the submission (SCAN 1/13/99). Trex is in ongoing discussion with the agency and is in the process of submitting data the FDA said it needs before it can approve the product, Cheung said. Trex does not believe it will need to conduct additional clinical trials and hopes TDMS will be approved by the end of this year.

GE declined to state its time line for filing a 510(k) application for Senographe 2000D. The company did say that it does not plan to wait until the FDA guidelines are released before filing the 510(k) for the product, executives said.

In other digital x-ray news, GE reported that it is ready to begin European installations of its Revolution XQ/i digital chest x-ray system. Revolution XQ/i was introduced at last year’s RSNA meeting and is based on the same amorphous silicon detectors used in Senographe 2000D. The first Revolution unit will be shipped to University Hospital in Gottingen, Germany, while a second system will be sent to Georges Pompidou Hospital in Paris.