Danieli Moura Brasil1, Ruben Pauwels2,3,4, Wim Coucke5, Francisco Haiter-Neto1, Reinhilde Jacobs2,6. 1. 1 Department of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas (UNICAMP) , Piracicaba, Sao Paulo , Brazil. 2. 2 OMFS-IMPATH Research Group, Department of Imaging and Pathology, Faculty of Medicine, Catholic University of Leuven, and Oral & Maxillofacial Surgery, University Hospitals Leuven , Leuven , Belgium. 3. 3 Department of Mechanical Engineering, Catholic University of Leuven , Leuven , Belgium. 4. 4 Department of Radiology, Faculty of Dentistry, Chulalongkorn University , Bangkok , Thailand. 5. 5 Freelance statistician, Brugstraat 107, 3001 Heverlee , Leuven , Belgium. 6. 6 Department of Dental Medicine, Karolinska Institutet , Stockholm , Sweden.
Abstract
OBJECTIVES: Dental CBCT exposure parameters should be optimized according to patient-specific indications, mainly for children that are most vulnerable to harmful effects of ionizing radiation. The aim of this study was to determine optimized kV settings for paediatric acquisitions for a dental CBCT device. METHODS: Clinical and quantitative evaluations of image quality were performed using 5 and 10 years old (y/o) anthropomorphic phantoms. Technical evaluation was performed with the SEDENTEXCT-IQ phantom. Images were obtained using a PaX-i3D Green CBCT (Vatech, Korea) device, combining tube voltages ranging from 85 to 110 kV and 2 fields of view (FOVs: 21 × 19 and 12 × 9 cm), while maintaining the radiation dose fixed by adjusting the mA accordingly. Clinically, observers assessed images based on overall quality, sharpness, contrast, artefacts, and noise. For quantitative evaluation, mean grey value shift, % increase standard deviation, % beam-hardening and contrast-to-noise ratio were calculated. For technical evaluation, segmentation accuracy, contrast-to-noise ratio and full width at half maximum were measured. Biplot graphs were used to choose representative parameters, from which the best kV was selected for each protocol and evaluation. kV values that had no statistical differences (p > 0.05) with the best kV chosen were considered as having the same quality. RESULTS: Clinically, 95 kV was found as a cut-off value. From the quantitative aspect, 85 kV (p < 0.05) showed the worst quality, except in 12 × 9 cm 5 y/o. Technically, 85 and 110 kV in the large FOV showed significantly worse quality for the large FOV. CONCLUSION: For paediatric indications, 95 kV or higher (and correspondingly low mA values) was found as optimal.
OBJECTIVES: Dental CBCT exposure parameters should be optimized according to patient-specific indications, mainly for children that are most vulnerable to harmful effects of ionizing radiation. The aim of this study was to determine optimized kV settings for paediatric acquisitions for a dental CBCT device. METHODS: Clinical and quantitative evaluations of image quality were performed using 5 and 10 years old (y/o) anthropomorphic phantoms. Technical evaluation was performed with the SEDENTEXCT-IQ phantom. Images were obtained using a PaX-i3D Green CBCT (Vatech, Korea) device, combining tube voltages ranging from 85 to 110 kV and 2 fields of view (FOVs: 21 × 19 and 12 × 9 cm), while maintaining the radiation dose fixed by adjusting the mA accordingly. Clinically, observers assessed images based on overall quality, sharpness, contrast, artefacts, and noise. For quantitative evaluation, mean grey value shift, % increase standard deviation, % beam-hardening and contrast-to-noise ratio were calculated. For technical evaluation, segmentation accuracy, contrast-to-noise ratio and full width at half maximum were measured. Biplot graphs were used to choose representative parameters, from which the best kV was selected for each protocol and evaluation. kV values that had no statistical differences (p > 0.05) with the best kV chosen were considered as having the same quality. RESULTS: Clinically, 95 kV was found as a cut-off value. From the quantitative aspect, 85 kV (p < 0.05) showed the worst quality, except in 12 × 9 cm 5 y/o. Technically, 85 and 110 kV in the large FOV showed significantly worse quality for the large FOV. CONCLUSION: For paediatric indications, 95 kV or higher (and correspondingly low mA values) was found as optimal.
Authors: Jeffrey C Kwong; J Martin Palomo; Michael A Landers; Alex Figueroa; Mark G Hans Journal: Am J Orthod Dentofacial Orthop Date: 2008-02 Impact factor: 2.650
Authors: Stefan Klein; Marius Staring; Keelin Murphy; Max A Viergever; Josien P W Pluim Journal: IEEE Trans Med Imaging Date: 2009-11-17 Impact factor: 10.048
Authors: M Loubele; R Jacobs; F Maes; K Denis; S White; W Coudyzer; I Lambrichts; D van Steenberghe; P Suetens Journal: Dentomaxillofac Radiol Date: 2008-09 Impact factor: 2.419