Monitoring cone- beam CT radiation dose levels in a University Hospital

Author(s)

Brasil, Danieli Moura ; Merken, Karen ; Binst, Joke ; Bosmans, Hilde ; Haiter-Neto, Francisco ; Jacobs, Reinhilde

• Document type: Journal article
• Source: Dentomaxillofacial Radiology; v. 52, n. 3, p. 11-pg., 2023-02-01.

Abstract

Objective: To present patient dose levels for different CBCT scanners, acquired by a dose monitoring tool in a University Hospital, as a function of field of view (FOV), operation mode, and patient age. Methods: An integrated dose monitoring tool was used to collect radiation exposure data [type of CBCT unit, dose -area product (DAP), FOV size, and operation mode] and patient demographic information (age, referral department) performed on a 3D Accuitomo 170 and a Newtom VGI EVO unit. Effective dose conversion factors were calculated and implemented into the dose moni-toring system. For each CBCT unit, the frequency of examinations, clinical indications, and effec-tive dose levels were obtained for different age and FOV groups, and operation modes. Results: A total of 5163 CBCT examinations were analyzed. Surgical planning and follow -up were the most frequent clinical indications. For the standard operation mode, effective doses ranged from 35.1 to 300 mu Sv and 9.26-117 mu Sv using 3D Accuitomo 170 and Newtom VGI EVO, respec-tively. In general, effective doses decreased with increasing age and FOV size reduction. Conclusions: Effective dose levels varied notably between systems and operation modes. Operation mode selection and FOV size were indication-oriented, with larger FOV sizes elec-tion serving surgical planning and follow -up. Seeing the influence of FOV size on effective dose levels, manufacturers could be advised to move toward patient-specific collimation and dynamic FOV selection. Systematically monitoring patient doses could be recommended for steering future CBCT optimization. (AU)

• FAPESP's process: 19/00682-0 - Determination of lower dose protocols with suitable image quality for an off-axis geometry computed tomography unit
• Grantee: Danieli Moura Brasil
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 20/03644-0 - Optimization strategies in CBCT thought development of institutional diagnostic reference levels of radiation dose and assessment of the influence of a narrow off-axis geometry computed tomography unit in image quality and radiation dose
• Grantee: Danieli Moura Brasil
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor