A Case for Wide-Angle Breast Tomosynthesis.
OBJECTIVE
Conventional mammography is largely limited by superimposed anatomy. Digital breast tomosynthesis (DBT) and computed tomography (CT) alleviate this limitation but with added out-of-plane artifacts or limited chest wall coverage. This article presents a wide-angle breast tomosynthesis (WBT), aimed to provide a practical solution to these limitations, and offers an initial study of its utility in comparison with DBT and CT using a singular evaluation platform.


METHODS
Using an anthropomorphic virtual breast phantom, a Monte Carlo code modeled a breast imaging system for three modalities of DBT, WBT, and breast CT (44°, 99°, and 198° total angle range, respectively) at four breast compression levels, all at a constant mean glandular dose level of 1.5 mGy. Reconstructed volumes were generated using iterative reconstruction methods. Lesion detectability was estimated using contrast-to-noise ratio and a channelized Hotelling observer model in terms of the area under the receiver operating characteristic (AUC).


RESULTS
Results showed improved detection with increased angular span and compression. The estimated AUCs for WBT were similar to that of CT. Comparative performance averaged over all thicknesses between CT and WBT was 4.3 ± 3.0%, whereas that between WBT and DBT was 5.6 ± 1.0%. At compression levels reflective of the modality (7-, 5-, and 4-cm thickness for CT, WBT, and DBT, respectively), WBT yielded an AUC comparable to CT (performance difference of 1.2%) but superior to DBT (performance difference of 5.5%).


CONCLUSIONS
The proposed imaging modality showed significant advantages over conventional DBT. WBT exhibited superior imaging performance over DBT at lower compression levels, highlighting further potential for reduced breast compression.
Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, 2424 Erwin Road, Suite 302, Durham, NC 27705; Department of Biomedical Engineering, Duke University, Durham, North Carolina; Department of Physics, Duke University, Durham, North Carolina; Department of Medical Physics, Duke University, Durham, North Carolina. Electronic address: samei@duke.edu.
Ehsan
E
Samei
Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, 2424 Erwin Road, Suite 302, Durham, NC 27705.
John
J
Thompson
Carl E. Ravin Advanced Imaging Laboratories, Department of Radiology, Duke University, 2424 Erwin Road, Suite 302, Durham, NC 27705.
Samuel
S
Richard
Department of Radiation Oncology, Duke University, Durham, North Carolina.
James
J
Bowsher
D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008327:Mammography / Q000295:instrumentation / Q000379:methods*; D019047:Phantoms, Imaging; D011856:Radiographic Image Enhancement / Q000295:instrumentation / Q000379:methods*; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013382:Subtraction Technique
Anthropomorphic breast phantom; Hotelling observer model; Monte Carlo simulation; iterative reconstruction; wide-angle breast tomosynthesis