OBJECTIVE: To quantify the effect of field of view (FOV) and angle of rotation on radiation dose in dental cone beam CT (CBCT) and to define a preliminary volume-dose model. METHODS: Organ and effective doses were estimated using 148 thermoluminescent dosemeters placed in an anthropomorphic phantom. Dose measurements were undertaken on a 3D Accuitomo 170 dental CBCT unit (J. Morita, Kyoto, Japan) using six FOVs as well as full-rotation (360°) and half-rotation (180°) protocols. RESULTS: For the 360° rotation protocols, effective dose ranged between 54 µSv (4 × 4 cm, upper canine) and 303 µSv (17 × 12 cm, maxillofacial). An empirical relationship between FOV dimension and effective dose was derived. The use of a 180° rotation resulted in an average dose reduction of 45% compared with a 360° rotation. Eye lens doses ranged between 95 and 6861 µGy. CONCLUSION: Significant dose reduction can be achieved by reducing the FOV size, particularly the FOV height, of CBCT examinations to the actual region of interest. In some cases, a 180° rotation can be preferred, as it has the added value of reducing the scan time. Eye lens doses should be reduced by decreasing the height of the FOV rather than using inferior FOV positioning, as the latter would increase the effective dose considerably. ADVANCES IN KNOWLEDGE: The effect of the FOV and rotation angle on the effective dose in dental CBCT was quantified. The dominant effect of FOV height was demonstrated. A preliminary model has been proposed, which could be used to predict effective dose as a function of FOV size and position.
OBJECTIVE: To quantify the effect of field of view (FOV) and angle of rotation on radiation dose in dental cone beam CT (CBCT) and to define a preliminary volume-dose model. METHODS: Organ and effective doses were estimated using 148 thermoluminescent dosemeters placed in an anthropomorphic phantom. Dose measurements were undertaken on a 3D Accuitomo 170 dental CBCT unit (J. Morita, Kyoto, Japan) using six FOVs as well as full-rotation (360°) and half-rotation (180°) protocols. RESULTS: For the 360° rotation protocols, effective dose ranged between 54 µSv (4 × 4 cm, upper canine) and 303 µSv (17 × 12 cm, maxillofacial). An empirical relationship between FOV dimension and effective dose was derived. The use of a 180° rotation resulted in an average dose reduction of 45% compared with a 360° rotation. Eye lens doses ranged between 95 and 6861 µGy. CONCLUSION: Significant dose reduction can be achieved by reducing the FOV size, particularly the FOV height, of CBCT examinations to the actual region of interest. In some cases, a 180° rotation can be preferred, as it has the added value of reducing the scan time. Eye lens doses should be reduced by decreasing the height of the FOV rather than using inferior FOV positioning, as the latter would increase the effective dose considerably. ADVANCES IN KNOWLEDGE: The effect of the FOV and rotation angle on the effective dose in dental CBCT was quantified. The dominant effect of FOV height was demonstrated. A preliminary model has been proposed, which could be used to predict effective dose as a function of FOV size and position.
Authors: M Loubele; R Jacobs; F Maes; F Schutyser; D Debaveye; R Bogaerts; W Coudyzer; D Vandermeulen; J van Cleynenbreugel; G Marchal; P Suetens Journal: Radiat Prot Dosimetry Date: 2006-02-03 Impact factor: 0.972
Authors: A D Goren; R D Prins; L T Dauer; B Quinn; A Al-Najjar; R D Faber; G Patchell; I Branets; D C Colosi Journal: Dentomaxillofac Radiol Date: 2013-02-14 Impact factor: 2.419
Authors: Marina Ernst; Peter Manser; Karl Dula; Werner Volken; Marco Fm Stampanoni; Michael K Fix Journal: Dentomaxillofac Radiol Date: 2017-07-27 Impact factor: 2.419
Authors: Andy Wai Kan Yeung; Nicolas Colsoul; Carla Montalvao; Kuofeng Hung; Reinhilde Jacobs; Michael M Bornstein Journal: Clin Oral Investig Date: 2019-02-09 Impact factor: 3.573