Tomographic mammography using a limited number of low‐dose cone‐beam projection images

Abstract

A method is described for using a limited number (typically 10-50) of low-dose radiographs to reconstruct the three-dimensional (3D) distribution of x-ray attenuation in the breast. The method uses x-ray cone-beam imaging, an electronic digital detector, and constrained nonlinear iterative computational techniques. Images are reconstructed with high resolution in two dimensions and lower resolution in the third dimension. The 3D distribution of attenuation that is projected into one image in conventional mammography can be separated into many layers (typically 30-80 1-mm-thick layers, depending on breast thickness), increasing the conspicuity of features that are often obscured by overlapping structure in a single-projection view. Schemes that record breast images at nonuniform angular increments, nonuniform image exposure, and nonuniform detector resolution are investigated in order to reduce the total x-ray exposure necessary to obtain diagnostically useful 3D reconstructions, and to improve the quality of the reconstructed images for a given exposure. The total patient radiation dose can be comparable to that used for a standard two-view mammogram. The method is illustrated with images from mastectomy specimens, a phantom, and human volunteers. The results show how image quality is affected by various data-collection protocols.

Contrast Detail Phantom Comparison on a Commercially Available Unit. Digital Breast Tomosynthesis (DBT) versus Full-Field Digital Mammography (FFDM)

“…10,11 In order to give a real 3D view of the breast, while retaining as much as possible the same acquisition geometry of the FFDM, the digital breast tomosynthesis (DBT) was developed. [12][13][14] This is a cone-beam, limitedangle (15-60°) tomographic technique able to reconstruct the whole breast volume from a sequence of projection-view mammograms. Due to the reduced acquisition angle, reconstruction artifacts are expected and many studies, both on human subject and phantom, are addressed to evaluate and improve the DBT image quality.…”

Comparison of Reconstruction Algorithms for Decreasing the Exposure Dose During Digital Tomosynthesis for Arthroplasty: a Phantom Study

“…The parameter σ 0 includes not only the photon statistics and electronic noise in the results but also the structural noise that can obscure the object. Wu et al proposed an ASF metric for quantifying artifacts observed in planes outside the focus image plane [20]. These artifacts, which resemble real features, are generated from real features located within the focus image plane.…”

“…MLEM identifies the reconstructed image that maximizes the likelihood of observing the particular projection measurements [20]. Because each iteration of the MLEM algorithm amplifies the high-frequency noise in the data, a reduction in the number of iterations may optimize the detection of low-contrast objects in this method.…”

“…Here, we explore the following three reconstruction techniques: conventional FBP, statistical IR-maximum likelihood expectation maximization (MLEM) [20], and an algebraic reconstruction technique (i.e., SIRT). We evaluate and compare the characteristics of the reconstructed images and the possible reduction in the radiation dose, applying the FBP, SIRT, and MLEM algorithms to prosthesis phantoms.…”

Impulse response and Modulation Transfer Function analysis for Shift-And-Add and Back Projection image reconstruction algorithms in Digital Breast Tomosynthesis (DBT)

“…DBT has been considered as a promising technique to reconstruct three-dimensional information of the breast to improve early breast cancer detection. Compared with standard mammography two-dimensional imaging techniques, DBT improves conspicuousness of structures by removing the visual clutter associated with overlying anatomy (Dobbins III and Godfrey, 2003;Chen et al, 2005;Niklason et al, 1997;Wu et al, 2003;Chen et al, 2007;Bissonnette et al, 2005;Zhang et al, 2006).…”