Left to right: Kristen Gavern R.T. (R)(M), Bonita West R.T. (R) (M), and Suzanne Martin R.T. (R)(M)

But digital mammography, which transfers the breast image directly to a digital format, has been demonstrated to be much more effective at detecting cancers in these groups of women and a recent study by the Digital Mammographic Imaging Screening Trial (DMIST) Investigators Group is convincing more and more screening facilities to invest in digital mammography technology.

“We had converted everything in the office to digital except for mammography,” said Kurt Newcomer, administrator for Kitsap County’s Advanced Medical Imaging (AMI), which added digital mammography to its Women’s Diagnostic Center in November. The hesitation when it came to converting mammography to digital: it was an expensive investment of relatively untested technology.

“Mammography has a very thin margin,” said Newcomer, who estimates AMI’s conversion to digital cost more than three-quarters of a million dollars. “We didn’t want to spend that money if it’s not shown to be better.”

But when the DMIST study results were released and published in the New England Journal of Medicine in fall 2005, the evidence that digital mammography could be a more effective diagnostic tool, particularly for those three subsets of women, was fairly overwhelming.

In the study, which started in 2001 and followed nearly 50,000 women, digital mammography detected between 15 and 28 percent more cancers in women younger than 50. It detected 15 percent more cancers in women with dense breasts — who are often at a greater risk for breast cancer — and 21 percent more cancers in premenopausal women. These three subsets comprised 65 percent of the women who participated in the study.

“It’s a significant difference,” said Newcomer. “The reason we decided to make the leap is digital mammography is clearly better for our patients.”

From an exam standpoint, digital mammography is much the same as film mammography, including the dreaded, yet unavoidable, breast compression.

“There are lots of good reasons why good compression is necessary,” said Newcomer. “There are a lot of structures in the breast.”

Compression, continued Newcomer, keeps these structures from overlapping each other in the image.

Digital mammography exams may be shorter, however, since digital images can be seen immediately on the computer screen, so technicians can see immediately if the image is sufficient. In addition digital images can be manipulated by radiologists, to magnify areas of concern, for example, often eliminating the need for additional views. And when digital mammography is combined with computer assisted diagnosis (CAD), which obtains a second, computerized reading, it can help detect more cancers or more accurately gauge signs of potential malignancies.

“CAD can tell the radiologist to go back and look at a potential problem area again,” said Newcomer.

Another advantage of digital mammography is that storing and sharing digital images is much less labor and space intensive than traditional x-ray film.

“It makes it easier to handle data,” said Newcomer. Digital images can be easily stored on a computer hard drive and quickly shared with physicians or other diagnostic professionals without worrying about whether a piece of film will be returned.

Digital mammography can not be said to have quite made the mainstream when it comes to medical technology. Out of the 8,832 facilities certified by the FDA (the governing body that accredits facilities and units for use) as of Dec. 1, 2006, only 1,373 — or 15.5 percent — of those facilities had digital mammography units. But that’s still a 6.5 percent increase from a year ago.

AMI is the first facility in Kitsap County to offer digital mammography. The next closest digital mammography facility is TRA Imaging, which has offices in Tacoma and Gig Harbor.