CHICAGO--Initial experience with a prototype digital mammography system indicates that the new technology has the potential to detect breast tumors much smaller in size than is possible with conventional mammography, and can be manipulated to explore areas of breast tissue that harbor occult cancer.
As a result of positive preliminary research results, full-scale clinical trials of the digital mammography system will begin in the next few months, Martin Yaffe, PhD, reported at the Radiological Society of North America meeting.
In tests using contrast-detail and mammographic phantoms that simulate signs of cancer or other breast disease, as well as actual breast scans from volunteers, the digital system has achieved spatial resolution of images as small as 1/20th of a millimeter. [Oncology News International's original report on Dr. Yaffe's research (August, 1994) includes a digital phantom image.]
"In laboratory tests, we've seen smaller, more subtle structures than can be seen with conventional mammography," said Dr. Yaffe, senior scientist, Imaging Research Program, Sunnybrook Health Science Centre, and professor of radiology and medical biophysics, University of Toronto, Canada.
With special computer graphics techniques, the system has increased the clarity of images of dense breast tissue, which is difficult to screen for cancer mammographically, and it has enhanced the depiction of fibers or deposits that often define the extent of breast cancer.
'Zoom in' for a Closer Look
"The image can be altered on the digital mammography system to highlight an area where a cancer might be obscured by normal tissue because a woman has dense breasts," Dr. Yaffe said. The radiologist also can 'zoom in' for a closer look at microcalcifications or other masses that are suspicious for cancer, he said.