Pressures in a simulated breast subjected to compression forces comparable to those of mammography. Work in Progress.

Abstract

To determine the magnitude and distribution of pressures in breast models subjected to mammographic compression forces. A vinyl-wrapped, unleavened-bread-dough breast model was compressed. Pressures in the dough models were measured with a strain gauge connected to a water-filled sensor. Under broad compression, pressures were uniform (range, 2.76-22.06 kPa [0.4-3.2 psi]). Spot compression increased pressures by as much as 60%. Pressures dropped sharply outside of paddle margins. No pressure differentials were found near small, deep simulated masses. The pressure of large masses increased by 50% when subjected to full compression force. Vigorous digital palpation resulted in a pressure of more than 41.40 kPa (6 psi). General pressures were mild and uniform. Internal pressures varied inversely with the area to which force was applied. Pressure dissemination was restricted by the cohesive binder and allowed zones of greater pressure to form directly under the applied force. The surrounding matrix disseminated pressure and protected small masses; large masses, bearing the force of the paddle, were exposed to greater pressure. Digital palpation administered high pressures.