Dif in Tro Duc Tion

In a pre vi ous study, it was noted that in some cases when com pres sive strains greater than about 5% were ap plied to tu mors re moved from the breast, there was an abrupt and ir re vers ible change in the tis sue stiff ness. The data from that study were fur ther an a lyzed and in fil trat ing ductal car ci no mas with and with out lob u lar fea tures were se lected for ad di tional test ing to ex plore their be hav ior un der com pres sive strains from 0-10%. Fresh tu mor sam ples were tested us ing a servo-hy drau lic Instron test ing ma chine to ap ply ramp type dis place ment loads to the sam ples. The re sults show that when strains greater than 5% are ap plied to the tu mor tis sue with out lob u lar fea tures, there is an ir re vers ible de crease in the stiff ness of the tis sue while no such change is noted in the other tu mor tis sue. The im pli ca tions for this be hav ior in mak ing mammographic and elastographic im ages of the breast were then ex plored us ing fi nite el e ment sim u la tions to de ter mine un der what com pres sion con di tions could the crit i cal strain thresh old be reached in the tu mor tis sue.