Affiliations: Tianjin University, Tianjin, China | Center for Bioengineering and School of Electrical and
Computer Engineering, University of Oklahoma, Norman, OK, USA | Department of Radiology, University of Alabama at
Birmingham, Birmingham, AL, USA
Note: [] Corresponding author: Hong Liu, Center for Bioengineering and
School of Electrical and Computer Engineering, University of Oklahoma, Norman,
OK, USA. E-mail: liu@ou.edu
Abstract: Objective: The purpose of this study was to develop a phantom-based
experimental calibration method to minimize the reconstruction artifacts for
the geometric misalignments of the digital tomosynthesis prototype. Methods: A calibration phantom with ten fiducial markers was designed. Using
this calibration phantom, the projection matrices of an experimental digital
tomosynthesis prototype were acquired from each projection view under a series
of misalignment conditions. The American College of Radiology mammography
phantom was imaged and reconstructed with and without using the correction of
the corresponding calibration projection matrices. The effectiveness of the
calibration technique was then quantitatively analyzed through comparison of
the calibrated and uncalibrated images. Results: As the isocenter horizontal-shift increases, the reconstruction artifacts become clearly
distinguishable. Using the calibration technique, the reconstruction artifacts
resulting from the isocenter horizontal-shift were effectively minimized for
the prototype. Conclusions: For the specific experimental conditions
utilized in this study, the phantom-based calibration method effectively
reduced reconstruction artifacts for the prototype investigated in this study.
The calibration method holds potential to benefit other tomosynthesis applications.
Keywords: Digital tomosynthesis, calibration, projection matrix, calibration phantom
