Share Email Print
cover

Proceedings Paper

Quantitative comparison of spatial resolution in step-and-shoot and continuous motion digital breast tomosynthesis
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

This study compares the spatial resolution in step-and-shoot and continuous motion acquisition modes of digital tomosynthesis using a bench-top prototype designed for breast phantoms imaging. The prototype employs a flat panel detector with a 50 μm pixel pitch, a micro focus x-ray tube and a motorized stage. A sharp metal edge with a thickness of 0.2 mm was used to measure the modulation transfer function (MTF). The edge was rotated from −7.5° to +7.5° with 1.5° increments to acquire 11 angular projections using 40 kVp, 500 μA with 5.55 s per projection. In continuous motion mode, the motorized stage moved the test object for the whole exposure time at a speed of 0.377 mm/s. The impact of acquisition speed in continuous DBT was also investigated, and a high speed of 0.753 mm/s was used. In step-and-shoot mode, the cutoff frequencies (10% MTF) in projection view (0°) and reconstructed DBT slices were 5.55 lp/mm and 4.95 lp/mm. Spatial resolution dropped in the continuous motion mode of the DBT due to the blur caused by the rotation of the stage and the cutoff frequencies reduced to 3.6 lp/mm and 3.18 lp/mm in the projection view (0º) and reconstructed DBT slices. At high rotational speed in continuous motion mode, the cutoff frequencies in the DBT slices dropped by 17 % to 2.65 lp/mm. Rotational speed of the rotation stage and spatial resolution are interconnected. Hence, reducing the motion blur in the continuous acquisition mode is important to maintain high spatial resolution for diagnostic purposes.

Paper Details

Date Published: 30 March 2016
PDF: 6 pages
Proc. SPIE 9783, Medical Imaging 2016: Physics of Medical Imaging, 97836D (30 March 2016); doi: 10.1117/12.2216102
Show Author Affiliations
Muhammad U. Ghani, The Univ. of Oklahoma (United States)
Di Wu, The Univ. of Oklahoma (United States)
Molly D. Wong, The Univ. of Oklahoma (United States)
Liqiang Ren, The Univ. of Oklahoma (United States)
Bin Zheng, The Univ. of Oklahoma (United States)
Kai Yang, Massachusetts General Hospital (United States)
Xizeng Wu, The Univ. of Alabama at Birmingham (United States)
Hong Liu, The Univ. of Oklahoma (United States)


Published in SPIE Proceedings Vol. 9783:
Medical Imaging 2016: Physics of Medical Imaging
Despina Kontos; Thomas G. Flohr, Editor(s)

© SPIE. Terms of Use
Back to Top