Magnus Dustler, with the Department of Translational Medicine, argued in his thesis, “Pressure distribution in mammography: Mechanical imaging and implications for breast compression,” that strong compression of the breast by rigid compression plates do not necessarily result in superior, cancer-detecting images, and recommends changes that might be more advantageous to clinicians and easier on patients.
Dustler collected patient data from Skåne University Hospital in Malmö, and conducted precise measurements of how pressure is distributed across the breast during a mammography.
He found that “reducing compression by half has little effect on how the pressure is distributed over the central areas of the breast. And they are the ones which are most important for cancer diagnosis,” according to a press release.
He also argues that flexible compression plates, which adapt to the inclination of the breast, may better distribute pressure. These plates reduce the pressure on the stiff tissue closest to the chest wall, but increase it on central breast areas to improve screening results.
“Flexible plates therefore enable better image quality without increased compression force,” Dustler said, noting that the equipment currently in mammograms is largely equivalent to that used in 1960s, the infancy of mammographic technology.
Regular mammograms are recommended for women between the ages of 40 and 74 to detect abnormal changes and tumors in the breast as early as possible. Despite this, a large proportion of all breast cancer cases are detected by the patients themselves.
One reason may be that some women do not take part in regular screening programs, partly because — previous research has shown — of the pain involved.
Current mammography screenings can also lead to questionable results, with women being asked to undergo further examinations because of uncertainties in their original screening. Only 10% to 20% of those recalled for suspect changes are found to have breast cancer.
Dustler believes that his findings could lower the number of such recalls. In addition to the possibility of flexible plates, he recommends that pressure measurement sensors be added to compression plates, so that images better pick up potential tumors, which are stiffer than surrounding tissue and fat.
“The results indicate that it could be possible to set a threshold value [from measurements of data collected in images]: women who exceed this threshold would undergo additional investigation,” Dustler said.
Because little research has been conducted into mammography equipment, despite its worldwide use, he plans to continue studies into pressure, pain, and image quality in such screenings.