Abstract Archives of the RSNA, 2014
Jerry E. De Groot MS, Abstract Co-Author: Nothing to Disclose
Woutjan Branderhorst PhD, Presenter: Employee, SigmaScreening BV
Mireille Broeders PhD, Abstract Co-Author: Nothing to Disclose
Cornelis A. Grimbergen PhD, Abstract Co-Author: Founder, Sigmascreening
Employee, Sigmascreening
Board Member, Sigmascreening
Patent holder, Sigmascreening
Gerard J. den Heeten MD, PhD, Abstract Co-Author: Founder, Sigmascreening
In mammography, mechanical compression often causes discomfort and pain in Europe. Depending on the individual technician, the compression force is typically adjusted to breast size, composition, skin tautness and pain tolerance. Prior research showed that this leads in practice to a large variation in pressure, ranging from <3 kPa (23 mmHg) to >30 kPa (225 mmHg). We developed a device that displays the average pressure during compression, to standardize the pressure on current mammographic devices that only display force. We aim to study the effects of standardizing pressure on absorbed glandular dose (AGD), the number of required retakes and reported pain, and compare it with standardizing force as the best available alternative.
A double-blinded randomized controlled trial was performed on 433 asymptomatic women scheduled for screening mammography. For each participant, three of the four compressions were standardized to a target force of 14 daN. One randomly assigned compression was standardized to a target pressure of 10 kPa (75 mmHg). Participants scored pain on a numerical rating scale. Three experienced breast screening radiologists indicated which images required a retake.
The average AGD and proportion of required retakes were in the normal range for the 10 kPa compressions. Average AGD values were 0.5% (MLO, not significant) – 3.2% (CC, p<0.001) lower for the 10 kPa protocol despite an average increase in breast thickness. The reader study showed no degradation of image quality; the proportion of retakes required for the 10 kPa compressions was 4.2% versus 1.4% (95% C.I. [0.4–4.4%]) for the 14 daN compressions. Average pain scores were 10% (MLO) – 24% (CC) lower in the 10 kPa protocol (p<0.001) and the proportion of women experiencing severe pain (NRS >= 7) was 27% (MLO) – 46% (CC) lower (p<0.001).
Mammographic compressions can be standardized to 10 kPa pressure without compromising radiation dose and apparent image quality, while being less painful than standardizing to 14 daN force which could substantially reduce complaints. Further research is required whether 10kPa (under arterial blood pressure) is the optimal target pressure.
For the millions of mammograms obtained yearly this study shows that a large amount of unnecessary pain can be avoided without adversely affecting radiation dose or the proportion of required retakes.
De Groot, J,
Branderhorst, W,
Broeders, M,
Grimbergen, C,
den Heeten, G,
A Standard for Mechanical Compression in Mammography?. Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL.
http://archive.rsna.org/2014/14018854.html