RSNA 2018

Abstract Archives of the RSNA, 2018


Mammographic Compression Variability Increased after Removing Real-Time Pressure Indicator

Monday, Nov. 26 3:40PM - 3:50PM Room: S502AB

FDA Discussions may include off-label uses.

Monique G. van Lier, MSc, Amsterdam, Netherlands (Presenter) Employee, SigmaScreening BV
Jerry E. De Groot, PhD, Amsterdam, Netherlands (Abstract Co-Author) Employee, SigmaScreening BV
Woutjan Branderhorst, PhD, Amsterdam, Netherlands (Abstract Co-Author) Employee, SigmaScreening BV
Laura J. Schijf, MD, Amsterdam, Netherlands (Abstract Co-Author) Nothing to Disclose
Cornelis A. Grimbergen, PhD, Amsterdam, Netherlands (Abstract Co-Author) Founder, SigmaScreening BV Employee, SigmaScreening BV Board Member, SigmaScreening BV Patent holder, SigmaScreening BV
Gerard J. den Heeten, MD,PhD, Nijmegen, Netherlands (Abstract Co-Author) Founder, SigmaScreening BV; Scientific Advisor, SigmaScreening BV; Patent Holder, SigmaScreening BV; Stock options, Volpara Health Technologies Limited; Medical Advisory Board, Volpara Health Technologies Limited

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When replacing a paddle with a pressure indicator, in a group of technicians familiar with the indicator, by a conventional paddle, the variability increased significantly leading to more unfavorable over- and under-compression.


A certain level of breast flattening in mammography is needed to obtain a high quality image. Generally accepted and quantifiable standards do not exists. Recent studies show that the level of compression pressure at exposure influences screening performance. Attempts are made to standardize the compression procedure by introducing pressure-based compression using a paddle equipped with a real-time pressure indicator. We aimed to study the impact on compression practice when replacing the pressure-based paddle with a conventional paddle without pressure indication in group experienced technicians.


Mammographic compression pressure was retrospectively obtained from mammographic images (VolparaAnalytics) and evaluated in two datasets from the same radiology department with the same technician team. The first dataset (4 years, n=11.561 compressions) was collected when using a compression paddle equipped with a real-time pressure indicator aiming for a 10kPa (75mmHg) compression pressure. The second dataset (3 months, n=1331 compressions) was collected 4 months after the mammography system with pressure indicator was replaced by a system without pressure indicator. The average compression pressure and variance significantly (P<0.001) increased from 11.23 0.04 kPa to 11.60 0.14 kPa (mean SEM) after removal of the pressure indicator. The proportion of compressions in the pressure range 5-15 kPa decreased from 87.4% to 77.9%. The proportion of high pressures (>15kPa) almost doubled (11.0% to 18.8%) and low pressures (<5kPa) more than doubled (1.6% to 3.3%).


When removing the pressure indicator, the initially low variability is increasing rapidly, indicating that an indicator is needed to remain high compression reproducibility. An increase in over- and under-compression can ultimately lead to decreased mammographic performance.