Masuda Takanori, Funama Yoshinori, Nakaura Takeshi, Sato Tomoyasu, Oku Takayuki, Ono Atsushi, Awai Kazuo
Department of Radiological Technology, Faculty of Health Science and Technology, Kawasaki University of Medical Welfare, 288, Matsushima, Kurashiki, Okayama, 701-0193, Japan.
Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
Radiol Phys Technol. 2025 Mar;18(1):293-299. doi: 10.1007/s12194-024-00855-1. Epub 2024 Nov 5.
The air-gap method is a technique employed to control dose distribution and radiation scattering in medical imaging. By introducing a layer of air between the radiation source and the object, this method effectively reduces the impact of scattered radiation. The purpose of this study was to investigate the suitability of the air-gap method for radiation dose reduction in pediatric patients during computed tomography (CT) examinations. Only one type of neonate phantom is used with 64 detector-row CT scanner while helical scanning the chest. The distance between the CT table and the subject was 0 mm at the conventional method and 150 mm at the air-gap method. The values of the real-time skin dosimeter on the dorsal surface of the body, and on the left and right mammary glands and image noise are measured and compared for each method. Compared with the conventional method, it was possible to reduce the exposure dose and image noise by approximately 10% and 15%, respectively, using the air-gap method (p < 0.05). The air-gap method was useful for reducing the radiation dose during pediatric CT examinations compared with the conventional method.
气隙法是一种用于控制医学成像中剂量分布和辐射散射的技术。通过在辐射源和物体之间引入一层空气，该方法有效地减少了散射辐射的影响。本研究的目的是探讨气隙法在儿科患者计算机断层扫描（CT）检查中降低辐射剂量的适用性。在使用64排探测器CT扫描仪对胸部进行螺旋扫描时，仅使用了一种新生儿体模。传统方法下CT检查床与受检者之间的距离为0毫米，气隙法下为150毫米。分别测量并比较了两种方法下身体背部、左右乳腺处实时皮肤剂量仪的值以及图像噪声。与传统方法相比，使用气隙法可分别将照射剂量和图像噪声降低约10%和15%（p < 0.05）。与传统方法相比，气隙法在儿科CT检查中有助于降低辐射剂量。
