Evaluation of pressure-controlled mammography compression paddles with respect to force-controlled compression paddles in clinical practice

ObjectivesTo reduce pain and discomfort associated with breast compression in mammography, a pressure-controlled compression paddle was recently introduced.The objective was to evaluate the pressure-controlled paddle by comparing it to the standard force-controlled paddle.MethodsDifferences of compressed breast thickness (CBT), compression force, compression pressure, and average glandular dose (AGD) between annual follow-up full-field digital mammography exams of 3188 patients were retrospectively examined. Two groups were compared: (1) force-force group (FF-group), both examinations were performed with the force-controlled paddle, and (2) force-pressure group (FP-group), only the follow-up examination was performed with the pressure-controlled paddle.In an additional group of patients, pain scores on a scale of 0 (no pain at all) to 10 (worst pain imaginable) were evaluated prospectively (n=343) who were randomly assigned to either paddle.ResultsMedian differences between follow-up exams in CBT, compression force, compression pressure, and AGD were for the FF- and FP-group respectively -1.0 vs 0.0mm (p<0.001); 0.0 vs-1.0daN (p=0.002); -1.0 vs -0.5kPa (p=0.005); and 0.05 vs -0.02mGy (p<0.001). These differences were, although statistically significant, clinically non-relevant (defined as CBT >2mm; force >2daN; pressure >1kPa and AGD >0.1mGy). The subanalysis dividing CBT into five categories revealed similar results. The median [interquartile range] pain scores were 6 [3, 7] and 5 [3, 7] for the force-controlled and pressure-controlled paddle, respectively, which was not significantly different (p=0.113).ConclusionsWe observed no clinically relevant differences in CBT, compression force, compression pressure, AGD, or pain score between the force- and pressure-controlled paddle. As such, we found no basis for preferring one paddle over the other.Key Points The pressure-controlled paddle did not show any clinically relevant changes in breast compression parameters compared to the force-controlled paddle. The pressure-controlled paddle did not lead to significant reduction in pain scores indicated by the patients compared to the force-controlled paddle. A large variation in compression force and compression pressure was observed in mammography exams for the both the force- and pressure-controlled compression paddle.