A comparison of limited-angle CBCT photon-counting and flat-panel digital mammography in perceived detection and visualization of breast lesions

This investigation aimed to compare perceived lesion detectability and visibility between limited-angle cone-beam computed tomography (CBCT) photon-counting (PC) and flat-panel (FP) mammography at equivalent radiation-dose levels. Projection data were collected by rotating a lesion-containing, humanlike breast phantom and acquiring images at every other degree using both a PC and an FP system, resulting in 5-13 projections over an 8-24° angular range. Feldkamp-Davis-Kress (FDK) and simultaneous iterative reconstruction technique (SIRT) algorithms were used to reconstruct three-dimensional (3D) volumes for each system. A reader study evaluated lesion detectability and visibility in the 3D data. PC-CBCT showed better detectability and visibility of masses compared to FP-CBCT, with 90% sensitivity versus 70% and an area under the visual grading curve (AUCVGC) of 0.66-0.71 (P < .05). FDK image volumes demonstrated improved calcification visibility (P < .05) with PC-CBCT over FP-CBCT; however, for SIRT, calcification visibility was lower (AUCVGC = 0.46). This study emphasizes the need to reassess photon-counting in 3D mammography to improve lesion detection and visibility.