Ludlow John B, Ivanovic Marija
Department of Diagnostic Sciences and General Dentistry, University of North Carolina School of Dentistry, Chapel Hill, North Carolina 27599-7450, USA.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2008 Jul;106(1):106-14. doi: 10.1016/j.tripleo.2008.03.018. Epub 2008 May 27.
This study compares 2 measures of effective dose, E(1990) and E(2007), for 8 dentoalveolar and maxillofacial cone-beam computerized tomography (CBCT) units and a 64-slice multidetector CT (MDCT) unit.
Average tissue-absorbed dose, equivalent dose, and effective dose were calculated using thermoluminescent dosimeter chips in a radiation analog dosimetry phantom. Effective doses were derived using 1990 and the superseding 2007 International Commission on Radiological Protection (ICRP) recommendations.
Large-field of view (FOV) CBCT E(2007) ranged from 68 to 1,073 microSv. Medium-FOV CBCT E(2007) ranged from 69 to 560 microSv, whereas a similar-FOV MDCT produced 860 microSv. The E(2007) calculations were 23% to 224% greater than E(1990).
The 2007 recommendations of the ICRP, which include salivary glands, extrathoracic region, and oral mucosa in the calculation of effective dose, result in an upward reassessment of fatal cancer risk from oral and maxillofacial radiographic examinations. Dental CBCT can be recommended as a dose-sparing technique in comparison with alternative medical CT scans for common oral and maxillofacial radiographic imaging tasks.
本研究比较了8台牙颌面锥形束计算机断层扫描（CBCT）设备和1台64层多层螺旋CT（MDCT）设备的两种有效剂量测量方法，即E(1990)和E(2007)。
在辐射模拟剂量测定体模中使用热释光剂量计芯片计算平均组织吸收剂量、当量剂量和有效剂量。有效剂量是根据1990年以及取代它的2007年国际放射防护委员会（ICRP）的建议得出的。
大视野（FOV）CBCT的E(2007)范围为68至1073微希沃特。中视野CBCT的E(2007)范围为69至560微希沃特，而类似视野的MDCT产生的有效剂量为860微希沃特。E(2007)的计算结果比E(1990)高23%至224%。
ICRP 2007年的建议在计算有效剂量时纳入了唾液腺、胸外区域和口腔黏膜，导致对口腔颌面放射检查的致命癌症风险重新评估后有所上升。与用于常见口腔颌面放射成像任务的替代医学CT扫描相比，牙科CBCT可作为一种剂量节省技术推荐使用。
