Performance evaluation of digital breast tomosynthesis systems: physical methods and experimental data

Abstract

Digital breast tomosynthesis (DBT) has become a well-established breast imaging technique, whose performance has been investigated in many clinical studies, including a number of prospective clinical trials. Results from these studies generally point to non-inferiority in terms of microcalcification detection and superior mass-lesion detection for DBT imaging compared to digital mammography (DM). This modality has become an essential tool in the clinic for assessment and ad-hoc screening but is not yet implemented in most breast screening programmes at a state or national level. While evidence on the clinical utility of DBT has been accumulating, there has also been progress in the development of methods for technical performance assessment and quality control of these imaging systems. DBT is a relatively complicated “pseudo-3D” modality whose technical assessment poses a number of difficulties. This paper reviews methods for the technical performance assessment of DBT devices, starting at the component level in part one and leading up to discussion of system evaluation with physical test objects in part two. We provide some historical and basic theoretical perspective, often starting from methods developed for DM imaging. Data from a multi-vendor comparison are also included, acquired under the medical physics QC protocol developed by EUREF and currently being consolidated by a European Federation of Organisations for Medical Physics (EFOMP) working group. These data and associated methods can serve as a reference for the development of reference data and provide some context for clinical studies.

Technical note: Realization and uncertainty analysis for an adjustable 3D structured breast phantom in digital breast tomosynthesis

“…The spiculated masses from the L1 were replaced by more non‐spiculated masses resulting in smaller size differences between the masses. It was possible to modify the printing process to allow a modular phantom design for a wide variety of different tomosynthesis machines which is necessary due to the high number of realizations with respect to angle range and reconstruction 16–18 . The masses are now printed together with the plate in a two‐component printing process which ensures also high reproducibility in orientation and positioning of the masses which results in an inter‐phantom variation ($${V}_{phantom}$$ = 0.321) in the same range as the inter‐human reader variation ($$\overline{{V}}_{inter}$$ = 0.383).…”

“…In addition, this manufacturing process allows the number and size of non-spiculated masses to be adjusted to accommodate the wide variety of DBT systems in terms of angular range and reconstruction. [16][17][18] For the printing process it was necessary to test new materials that were both available for the printer and met the requirements in terms of attenuation characteristics. The absorption difference between the lesion models and the background was improved compared to the L1 phantom.…”

Comparison of lesion detection and conspicuity between narrow-angle and wide-angle digital breast tomosynthesis for dense and non-dense breasts

“…These factors will impact the detection and conspicuity for different lesion types as well. While the physical characterizations and imaging performance on testing objects for different clinical DBT systems have been investigated previously in great detail, 44 our study focuses on a direct comparison of the clinical performance of two DBT systems using the same patient cohort.…”

“…Most of the previous studies on the impact of AR used simulations or phantoms and did not include clinical images. Other studies have compared the imaging performance of commercial DBT systems and mainly focused on the characteristics of physical properties for different systems 40 – 44 and detection performance of test objects in physical phantom 45 – 47 There has been a lack of direct comparison of the clinical performance between DBT systems with different AR for various lesion types and breast densities 5 .…”

Audit of data from examination image headers collected for quality assurance in the ECOG‐ACRIN EA1151 tomosynthesis mammographic imaging screening trial (TMIST)

“…In digital imaging, the choice of dose for a procedure is somewhat arbitrary although there are physics principles related to signal‐difference to noise ratio that mandate certain minimum numbers of quanta at the detector. For tomosynthesis, the situation is further complicated by differences in the number of angular views acquired in the examination 21,22 . This complexity likely explains the fact that after more than 10 years since the first FDA approval of a breast tomosynthesis system, their designs in terms of the number of views, angular range covered and other factors in image acquisition still vary considerably and little convergence to a standard design and dose has occurred.…”