J Koivisto1, J Wolff2, J Järnstedt3, P Dastidar4, M Kortesniemi5. 1. Department of Physics, University of Helsinki, Helsinki, Finland. Electronic address: juha.koivisto@planmeca.com. 2. Department of Oral and Maxillofacial Surgery/Oral Pathology, VU University Medical Center, Amsterdam, The Netherlands. 3. Department of Radiology, Medical Imaging Center, Tampere University Hospital, Tampere, Finland. 4. Department of Radiology, Medical Imaging Center, Tampere University Hospital, Tampere, Finland; University of Tampere Medical School, Tampere, Finland. 5. HUS Medical Imaging Center, University of Helsinki, Helsinki, Finland.
Abstract
OBJECTIVE: The objectives of this study were to assess the organ and effective doses (International Commission on Radiological Protection [ICRP] 103 standard) resulting from supine, prone, and oblique phantom positions in the maxillofacial region using a novel cone beam computed tomography (CBCT) device and to compare the results with conventional dental CBCT and multislice computed tomography (MSCT) devices. STUDY DESIGN: Measurements were performed using an anthropomorphic RANDO head phantom (Radiation Analogue Dosimetry System) with 20 MOSFET (metal-oxide-semiconductor field-effect transistor) dosimeters placed in the most radiosensitive maxillofacial organs. Effective doses were measured in 3 phantom positions using a combined extremity and maxillofacial CBCT device: the Planmed Verity CBCT scanner. Reference values were measured in the upright position with 2 CBCT devices and in the prone position with one MSCT scanner. RESULTS: The Planmed Verity CBCT scanner effective doses were 247 μSv in supine, 192 μSv in prone, and 134 μSv in oblique position. The effective dose with ProMax 3D MAX CBCT was 168 μSv; with i-CAT Next Generation, 170 μSv; and with Philips Brilliance 64 MSCT, 781 μSv. CONCLUSIONS: Head positioning has an important effect on the organ and effective doses. The Planmed Verity CBCT scanner effective dose results were comparable with those attained on 2 conventional CBCT devices and were considerably lower than the MSCT scanner results.
OBJECTIVE: The objectives of this study were to assess the organ and effective doses (International Commission on Radiological Protection [ICRP] 103 standard) resulting from supine, prone, and oblique phantom positions in the maxillofacial region using a novel cone beam computed tomography (CBCT) device and to compare the results with conventional dental CBCT and multislice computed tomography (MSCT) devices. STUDY DESIGN: Measurements were performed using an anthropomorphic RANDO head phantom (Radiation Analogue Dosimetry System) with 20 MOSFET (metal-oxide-semiconductor field-effect transistor) dosimeters placed in the most radiosensitive maxillofacial organs. Effective doses were measured in 3 phantom positions using a combined extremity and maxillofacial CBCT device: the Planmed Verity CBCT scanner. Reference values were measured in the upright position with 2 CBCT devices and in the prone position with one MSCT scanner. RESULTS: The Planmed Verity CBCT scanner effective doses were 247 μSv in supine, 192 μSv in prone, and 134 μSv in oblique position. The effective dose with ProMax 3D MAX CBCT was 168 μSv; with i-CAT Next Generation, 170 μSv; and with Philips Brilliance 64 MSCT, 781 μSv. CONCLUSIONS: Head positioning has an important effect on the organ and effective doses. The Planmed Verity CBCT scanner effective dose results were comparable with those attained on 2 conventional CBCT devices and were considerably lower than the MSCT scanner results.
Authors: Juha H Koivisto; Jan E Wolff; Timo Kiljunen; Dirk Schulze; Mika Kortesniemi Journal: J Appl Clin Med Phys Date: 2015-07-08 Impact factor: 2.102