New Device May Ease Mammography Discomfort
Researchers have developed a new device that may result in more comfortable mammography. According to a study presented in December 2014 at the annual meeting of the Radiological Society of North America (RSNA), standardizing the pressure applied in mammography would reduce pain associated with breast compression without sacrificing image quality.
A release from the society explains that compression of the breast is necessary in mammography to optimize image quality and minimize absorbed radiation dose. However, mechanical compression of the breast in mammography often causes discomfort and pain and deters some women from mammography screening.
An additional problem associated with compression is the variation that occurs when the technologist adjusts compression force to breast size, composition, skin tautness and pain tolerance. Over-compression, or unnecessarily high pressures during compression, is common in certain European countries, especially for women with small breasts. Over-compression occurs less frequently in the United States, where under-compression, or extremely low applied pressure, is more common.
The release quotes Woutjan Branderhorst, Ph.D., researcher in the Department of Biomedical Engineering and Physics at the Academic Medical Center in Amsterdam, as saying, “This means that the breast may be almost not compressed at all, which increases the risks of image quality degradation and extra radiation dose,” said.
Overall, adjustments in force can lead to substantial variation in the amount of pressure applied to the breast, ranging from less than 3 kilopascals (kPa) to greater than 30 kPa.
Dr. Branderhorst and colleagues theorized that a compression protocol based on pressure rather than force would reduce the pain and variability associated with the current force-based compression protocol. Force is the total impact of one object on another, whereas pressure is the ratio of force to the area over which it is applied.
The researchers developed a device that displays the average pressure during compression and studied its effects in a double-blinded, randomized control trial on 433 asymptomatic women scheduled for screening mammography.
Three of the four compressions for each participant were standardized to a target force of 14 dekanewtons (daN). One randomly assigned compression was standardized to a target pressure of 10 kPa.
Participants scored pain on a numerical rating scale, and three experienced breast screening radiologists indicated which images required a retake. The 10 kPa pressure did not compromise radiation dose or image quality, and, on average, the women reported it to be less painful than the 14 daN force.