Nachiko Uchiyama MD, Presenter: Nothing to Disclose

Hitomi Tani, Abstract Co-Author: Nothing to Disclose

Minoru Machida MD, PhD, Abstract Co-Author: Nothing to Disclose

Mari Kikuchi MD, Abstract Co-Author: Nothing to Disclose

Yasuaki Arai, Abstract Co-Author: Nothing to Disclose

RM (rotating mammogram) generates a 3D overview rendering of a reconstructed DBT volume. The purpose of this study is to compare the diagnostic accuracy of FFDM and DBT using and not using RM and to determine whether DBT plus RM will contribute to the assessment of breast cancer.

55 patients including 34 breasts with maligmant and 76 normal or benign breasts were recruited. 6 dedicated breast imaging radiologists evaluated the images utitizing ROC analysis. The 55 patient cases were randomly divided into two groups: group A (28 patients) and group B (27 patients). First, FFDM from group A and DBT with and without RM from group B were evaluated. Second, DBT with and without RM from group A and FFDM from group B were evaluated. Each participant completed two reading sessions spaced 4 weeks apart to minimize recall bias. Modified BI-RADS and percentage probability of malignancy (POM) scale were used and the reader-specific area under the curves (AUC) were analyzed. In addition, the visualization of masses and microcalcifications as well as the appearance of noise were also compared and scored separately for each case in DBT and RM on a 4-point scale from 0 to 3.  

For the BI-RADS scale, the average AUC for DBT plus RM was 0.907, DBT alone 0.901 and FFDM was 0.793. For POM, the average AUC for DBT plus RM was 0.915, DBT alone 0.907 and FFDM was 0.799. DBT plus RM demonstrated superior diagnostic accuracy compared with FFDM alone, as shown by significant difference in the average AUC (p<0.05). In terms of average AUC, only a small improvement was seen by DBT plus RM compared to DBT alone. Difference in the average AUC in BI-RADS between DBT plus RM and DBT alone was 0.006 and in POM was 0.008. For all 14 cancers manifesting as microcalcifications, the visualization was significantly better on RM than DBT (p<0.05). 

With the RM parameter settings used in this study, the combination of DBT plus RM showed only small improvement compared to that of DBT alone in terms of ROC curve area, sensitivity and specificity. Adjunction of RM to DBT will offer the benefit of increased diagnostic accuracy and contribute to more accurate assessment of DBT alone. The visualization of microcalcifications was significantly better on RM than DBT.

The RM could be used for improved 3D visualization of structures, e.g. microcalcifications, in DBT and could lead to faster DBT reading times. 

Uchiyama, N, Tani, H, Machida, M, Kikuchi, M, Arai, Y, Assessing Radiologist Performance and Microcalcifications Visualization Using Combined 3D Rotating Mammogram (RM) and Digital Breast Tomosynthesis (DBT).  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14003694.html