Source-detector trajectory optimization for FOV extension in dental CBCT imaging

• Published in: Computational and structural biotechnology journal Vol. 24; pp. 679 - 689
• Main Authors: Islam, S M Ragib Shahriar, Biguri, Ander, Landi, Claudio, Di Domenico, Giovanni, Schneider, Benedikt, Grün, Pascal, Sarti, Cristina, Woitek, Ramona, Delmiglio, Andrea, Schönlieb, Carola-Bibiane, Turhani, Dritan, Kronreif, Gernot, Birkfellner, Wolfgang, Hatamikia, Sepideh
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01-12-2024; Elsevier
• Subjects: Dental CBCT; Field of view; Image reconstruction; Interventional radiology; Trajectory optimization; Field of view; Interventional radiology; Dental CBCT; Image reconstruction; Trajectory optimization
• ISSN: 2001-0370; 2001-0370
• DOI: 10.1016/j.csbj.2024.11.010

In dental imaging, Cone Beam Computed Tomography (CBCT) is a widely used imaging modality for diagnosis and treatment planning. Small dental scanning units are the most popular due to their cost-effectiveness. However, these small systems have the limitation of a small field of view (FOV) as the source and detector move at a limited angle in a circular path. This often limits the FOV size. In this study, we addressed this issue by modifying the source-detector trajectory of the small dental device. The main goal of this study was to extend the FOV algorithmically by acquiring projection data with optimal projection angulation and isocenter location rather than upgrading any physical parts of the device. A novel algorithm to implement a Volume of Interest (VOI) guided trajectory is developed in this study based on the small dental imaging device's geometry. In addition, this algorithm is fused with a previously developed off-axis scanning method which uses an elliptical trajectory, to compensate for the existing constraints and to further extend the FOV. A comparison with standard circular trajectory is performed. The FOV of such a standard trajectory is a circle of 11 cm diameter in the axial plane. The proposed novel trajectory extends the FOV significantly and a maximum FOV of 19.5 cm is achieved with the Structural Similarity Index Measure (SSIM) score ranging between (≈98-99%) in different VOIs. The study results indicate that the proposed source-detector trajectory can extend dental imaging FOV and increase imaging performance, which ultimately results in more precise diagnosis and enhanced patient outcomes.
•A novel source-detector trajectory, proposed for dental CBCT field of view (FOV) expansion.•The achieved field of view is expanded from 11 cm to a maximum of 19.5 cm.•The FOV extension is done algorithmically rather than modifying the device hardware.•Image quality of the proposed trajectory outperforms the standard trajectory.