Dynamically-Collimated Digital Tomosynthesis Reconstruction by Using a Compressed-Sensing Based Algorithm

• Published in: Journal of the Korean Physical Society Vol. 76; no. 1; pp. 66 - 72
• Main Authors: Park, Soyoung, Kim, Guna, Cho, Hyosung, Seo, Changwoo, Lee, Minsik
• Format: Journal Article
• Language: English
• Published: Seoul The Korean Physical Society 01.01.2020; Springer Nature B.V; 한국물리학회
• Subjects: Algorithms; Collimation; Collimators; Computer simulation; Field of view; Image quality; Image reconstruction; Mathematical and Computational Physics; Particle and Nuclear Physics; Physics; Physics and Astronomy; Radiation dosage; System effectiveness; Theoretical; 물리학; Interior digital tomosynthesis; Compressed-sensing; Dynamic collimation
• ISSN: 0374-4884; 1976-8524
• DOI: 10.3938/jkps.76.66

Conventional digital tomosynthesis (DTS) reconstruction by using the filtered-backprojection algorithm requires a full field-of-view scan and relatively dense projections to obtain high-quality images, which results in a high radiation dose to patients. Interior DTS (iDTS) with a proper collimator offers a possible imaging modality for reducing the dose of radiation delivered because the X-ray beam is able to target a small region-of-interest (ROI) containing the target area. Collimators for iDTS often have a fixed rectangular shape, but focusing the X-ray beam on an arbitrarily shaped ROI would be preferable because it further reduces the excessive radiation dose. In this study, we propose a new iDTS scan method to create an ROI with an arbitrary shape to minimize the radiation dose at each angle of view. We used a compressed-sensing-based algorithm for accurate iDTS reconstruction. To validate the proposed method, we performed a systematic simulation and an experiment, and we investigated the image characteristics. Our results indicate that the proposed method may effectively reduce radiation dose in iDTS in real imaging systems.