Tomosynthesis implementation with adaptive online calibration on clinical C-arm systems

• Verfasst von: Chung, Khanlian [VerfasserIn]
• Verfasst von: Schad, Lothar R. [VerfasserIn]
• Verfasst von: Zöllner, Frank G. [VerfasserIn]
• Titel: Tomosynthesis implementation with adaptive online calibration on clinical C-arm systems
• Verf.angabe: Khanlian Chung, Lothar R. Schad, Frank G. Zöllner
• E-Jahr: 2018
• Jahr: [October 2018]
• Umfang: 15 S.
• Illustrationen: Illustrationen
• Fussnoten: Published online: 8 May 2018 ; Gesehen am 20.05.2019
• Titel Quelle: Enthalten in: International journal of computer assisted radiology and surgery
• Ort Quelle: Berlin : Springer, 2006
• Jahr Quelle: 2018
• Band/Heft Quelle: 13(2018), 10, Seite 1481-1495
• ISSN Quelle: 1861-6429
• DOI: doi:10.1007/s11548-018-1782-y
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Arbitrary scan trajectories
• Sach-SW: C-arm systems
• Sach-SW: Circular tomosynthesis
• Sach-SW: Cone beam computed tomography
• Sach-SW: Image-guided intervention
• Sach-SW: Online calibration
• K10plus-PPN: 1665916184

Abstract

PurposeCone beam computed tomography (CBCT) systems offer physicians crucial 3D and 2D imaging capabilities during interventions. However, certain medical applications only require very specific information from the CBCTs (e.g., determination of the position of high-contrast objects). In diagnostics, tomosynthesis techniques can be used in these cases to minimize dose exposure. Therefore, integrating such techniques on CBCT systems could also be beneficial for interventions. In this paper, we investigate the performance of our implementation of circular tomosynthesis on a CBCT device.MethodsThe tomosynthesis scan trajectory is realized with step-and-shoot on a clinical C-arm device. The online calibration algorithm uses conventionally acquired 3D CBCT of the scanned object as prior knowledge to correct the imaging geometries. The online calibration algorithm was compared to an offline calibration to test its performance. A ball bearing phantom was used to evaluate the reconstructions with respect to geometric distortions. The evaluation was done for three different scenarios to test the robustness of our tomosynthesis implementation against object deviations (e.g., pen) and different object positioning.ResultsThe circular tomosynthesis was tested on a ball bearing and an anthropomorphic phantom. The results show that the calibration is robust against isocenter shifts and object deviations in the CBCT. All reconstructions used 100 projections and displayed limited angle artifacts. The accuracy of the positions and shapes of high-contrast objects were, however, determined precisely. (The maximal center position deviation is 0.31 mm.)ConclusionFor medical procedures that primarily determine the precise position of high-contrast objects, circular tomosynthesis could offer an approach to reduce dose exposure.