tomosyntes

Tomosyntes, or tomosynthesis, is a tomographic imaging modality that creates quasi-3D representations from a series of two-dimensional X-ray projections taken at different angles over a limited arc. It is a form of limited-angle tomography that uses multiple low-dose exposures to reconstruct thin slices of the imaged region, giving a stack of images rather than a single flat view.

In digital breast tomosynthesis (DBT), the X-ray tube and detector move over a short angular range, typically around 15 to 50 degrees, capturing between about 15 and 60 projections. The collected data are reconstructed into a volumetric set of slices. Clinically, tomosynthesis is used most widely in breast imaging to reduce tissue overlap and improve lesion visibility. It may be used in conjunction with standard 2D mammography or, increasingly, with synthetic 2D images generated from the 3D data to limit additional radiation exposure.

Applications extend beyond breast imaging, with tomosynthesis explored for chest radiography and other body regions in research and some clinical settings. Advantages include improved detection and characterization of findings in structures with overlapping anatomy, better visualization in dense tissues, and the ability to review reconstructed slices in multiple planes. Limitations involve lower in-plane resolution compared to conventional CT, potential reconstruction artifacts, higher equipment and processing requirements, and varying radiation-dose considerations depending on protocol. As practice evolves, many centers use synthetic 2D images from the tomosynthesis data to minimize dose while maintaining diagnostic confidence.