Department of Radiology, Mayo Clinic College of Medicine, 200 First St SW, Rochester, MN 55905, USA.
Radiographics. 2011 May-Jun;31(3):835-48. doi: 10.1148/rg.313105079.
In addition to existing strategies for reducing radiation dose in computed tomographic (CT) examinations, such as the use of automatic exposure control, use of the optimal tube potential also may help improve image quality or reduce radiation dose in pediatric CT examinations. The main benefit of the use of a lower tube potential is that it provides improved contrast enhancement, a characteristic that may compensate for the increase in noise that often occurs at lower tube potentials and that may allow radiation dose to be substantially reduced. However, selecting an appropriate tube potential and determining how much to reduce radiation dose depend on the patient's size and the diagnostic task being performed. The power limits of the CT scanner and the desired scanning speed also must be considered. The use of a lower tube potential and the amount by which to reduce radiation dose must be carefully evaluated for each type of examination to achieve an optimal tradeoff between contrast, noise, artifacts, and scanning speed.
除了在计算机断层扫描（CT）检查中使用自动曝光控制等现有的降低辐射剂量策略外，还可以使用最佳管电压来提高图像质量或降低儿科 CT 检查中的辐射剂量。使用较低管电压的主要好处是它提供了更好的对比度增强，这种特性可以弥补在较低管电压下经常发生的噪声增加，并且可能允许大幅度降低辐射剂量。然而，选择适当的管电压并确定降低多少辐射剂量取决于患者的体型和要执行的诊断任务。还必须考虑 CT 扫描仪的功率限制和所需的扫描速度。必须仔细评估每种检查类型使用较低管电压和减少辐射剂量的程度，以在对比度、噪声、伪影和扫描速度之间实现最佳折衷。
