The relationship of the mean glandular dose with compressed breast thickness in mammography

The aim of the present study was to investigate the relationship between mean glandular dose (MGD) and compressed breast thickness (CBT) by using the data collected from a patient survey and the experiment results. Exposure parameters of 360 mammographic procedure that using AEC (automatic exposure control) mode were recorded and incident air kerma (K) were measured using a QA dosimeter then MGDs were calculated by using Dance’s formula. The data were categorized to four brands groups and analyze respectively. The results of the study showed that the CBT population ranged from 13 to 75 mm with a nominal distribution and mean thickness was 42 mm with standard deviation of 12 mm. MGD showed a positive correlation with CBT and incident air kerma (K). MGD in 2 of the 4 brand groups had a positive relation with CBT while other two groups did not show a similar trend. In a range of 20 to 60 mm, MGD showed a positive correlation with CBT. The results of the present study indicated that CBT could influence the MGD through multiple pathways and these pathways represent different mechanisms.