Breast tomosynthesis is a 3-dimensional (3-D) imaging technology that involves acquiring images of a stationary compressed breast at multiple angles during a short scan. The individual images are then reconstructed into a series of thin high-resolution slices that displayed individually or in a dynamic ciné mode. Tomosynthesis can reduce or eliminate the tissue overlap effect. While holding the breast stationary, images are acquired at a number of different x-ray source angles. Objects at different heights in the breast project differently for each angle. The final step in the tomosynthesis procedure is reconstructing the data to generate images that enhance objects from a given height by appropriate shifting of the projections relative to one another. Tomosynthesis has many properties that make it suitable as a modality for screening, including good diagnostic performance, short examination time and low radiation dose, it is a strong competitor to the current gold standard breast screening modality, i.e. mammography. At the same time, theoretical advantages have not yet been shown to translate into clinical advantage or even equivalence to standard mammography.
Metanalysis by Lei et al concluded: “Digital breast tomosynthesis has high sensitivity and specificity in breast diagnosis.• DBT appears to have superior diagnostic accuracy relative to digital mammography. • DBT images were captured at a lower dose than 2D images. • DBT displays abnormal features of lesions more clearly than DM. • Digital breast tomosynthesis could become the first choice for assessing breast lesions.”
In a statement in November 2014, while calling for more studies, the American College of radiology said:: To be clear: tomosynthesis is no longer investigational. Tomosynthesis has been shown to improve key screening parameters compared to digital mammography. “.
Yoo JY, Chung MJ, Choi B, Jung HN, Koo JH, Bae YA, Jeon K, Byun HS, Lee KS. Digital tomosynthesis for PNS evaluation: comparisons of patient exposure and image quality with plain radiography. Korean J Radiol. 2012 Mar;13(2):136-43. Epub 2012 Mar 7.
Tingberg A X-ray tomosynthesis: a review of its use for breast and chest imaging. Radiat Prot Dosimetry. 2010 Apr-May;139(1-3):100-7
ACR Statement on Breast Tomosynthesis, November 24, 2014. http://www.acr.org/About-Us/Media-Center/Position-Statements/Position-Statements-Folder/20141124-ACR-Statement-on-Breast-Tomosynthesis
Lei J, Yang P, Zhang L, Wang Y, Yang K.Diagnostic accuracy of digital breast tomosynthesis versus digital mammography for benign and malignant lesions in breasts: a meta-analysis. Eur Radiol. 2014 Mar;24(3):595-602.
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