Objective: The effects of different tube currents and voltages on image quality and radiation dose were studied to provide a theoretical basis for low-dose cone beam computed tomography (CBCT) scanning in children.
Methods: Different tube currents and voltages were used to scan the incisor area of fresh Bama pig heads by CBCT. The radiation dose was recorded, and image quality was evaluated.
Results: As the tube current or voltage decreased, the radiation dose and image quality gradually decreased. The computed tomographic dose index (CTDIvol) of 90 kV, 2.5 mA and 60 kV, 7.0 mA were all 1.7 mGy. The image quality score of the former was higher than that of the latter, and the difference between them was statistically significant (P<0.05).
Conclusions: Low-dose CBCT scanning appears to be able to reduce the necessary tube current during imaging by improving image quality.
目的 研究不同管电流、管电压对新鲜巴马猪猪头切牙区锥形束CT（CBCT）扫描时图像质量和辐射剂量的影响，为实现低剂量CBCT扫描提供理论依据。方法 将新鲜巴马猪猪头固定在CBCT扫描视野的中央，使用不同的管电流、管电压围绕切牙区进行360°扫描，记录辐射剂量，评价图像质量。结果 随着管电流或管电压的降低，辐射剂量逐渐下降，图像质量也逐渐下降。扫描参数90 kV、2.5 mA组合与60 kV、7.0 mA组合的平均容积CT剂量指数（CTDIvol）均为1.7 mGy，前者的图像质量评分高于后者，二者间差异具有统计学意义（P<0.05）。结论 在保证图像质量的前提下，降低管电流更能实现低剂量CBCT扫描。.
Keywords: cone beam computed tomography; low-dose; radiation dosage.