A prototype Multi-X-ray-source array (MXA) for digital breast tomosynthesis

Abstract

The design and testing of a prototype Multi-X-ray-source Array (MXA) for digital breast tomosynthesis is reported. The MXA is comprised of an array of tungsten filament cathodes with focus cup grid-controlled modulation and a common rotating anode housed in a single vacuum envelope. Prototypes consisting of arrays of three-source elements and eleven-source-elements were fabricated and evaluated. The prototype sources demonstrated focal spot sizes of 0.3 mm at 45 kV with 50 mA. Measured x-ray spectra were consistent with the molybdenum anode employed, and the tube output (air kerma) was between 0.6 mGy/100 mAs at 20 kV and 17 mGy/100 mAs at 45 kV with a distance of 100 cm. HVL measurements ranged from 0.5 mm Al at 30 kV to 0.8 mm Al at 45 kV, and x-ray pulse widths were varied from 20 ms to 110 ms at operating frequencies ultimately to be limited by source turn-on/off times of ~1 ms. Initial results of reconstructed tomographic data are presented. Keywordsdigital breast tomosynthesis; stationary x-ray source; multisource x-ray which captures the key aspects as they relate to the technology underlying the Multi-X-ray source Array (MXA).

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

“…Advances in source implementation include the development of multisource DBT systems in which a linear array of x-ray sources is distributed to cover some specific angular range (Qian et al 2012, Neculaes et al 2014, Calliste et al 2017, Becker et al 2020, Behling 2021. Rapid sequential switching of the sources covers the angular range while the individual sources remain stationary during acquisition.…”

“…CNT tubes have stationary anodes and therefore limited x-ray flux compared to rotating anode tubes, restricting the reduction in total scan time that can be achieved. Recent work by Becker et al (2020) has described a multi-x-ray source array (MXA) using an 11-source rotating anode array with molybdenum anodes and a 1 mm thick Al tube window, shown in figure 2. Measured x-ray tube output at 1 m for a single source in the array ranged from 6 μGy mAs −1 at 20 kV to 170 μGy mAs −1 at 45 kV.…”

Geometric comparison of chest tomosynthesis system with thermionic filament and carbon nanotube field emitter-based x-ray sources

“…This tube has focal spot size as 2.0 mm and 1.0 mm and are available for a maximum tube voltage 125kV. The conventional tomosynthesis system with a filament source mounted and the gantry moving increases the focal spot size during the time it is turned on and moving because X-rays are irradiated by thermionic emission that has an analog property [5,6]. As a result, motion blur occurs, and the quality and resolution of the X-ray image deteriorate.…”