University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA.
Medical Physics Department, Konstantopoulio General Hospital, Attiki, Greece.
Br J Radiol. 2021 Jan 1;94(1117):20200473. doi: 10.1259/bjr.20200473. Epub 2020 Oct 15.
The American Association of Physicists in Medicine (AAPM) Task Groups (TG) 204 and 220 introduced a method to estimate patient dose by introducing the Size-Specific Dose Estimate (SSDE). They provided patient size-specific conversion factors that could be applied to volumetric CT Dose Index CTDI to estimate patient dose in terms of SSDE based on either effective diameter (D) or water equivalent diameter (D). Our study presented an alternative method to manually estimate SSDE for the everyday clinical routine chest CT that can be readily used and does not require sophisticated computer programming.
For 16 adult patients undergoing chest CT, the method employed an average relative electron density (ρ = 0.3) for the lung tissue and a ρ of 1.0 for the other tissues to scale the lateral thickness and compute the effective lateral thickness on the patient's axial image. The proposed method estimated a "corrected" D (D) to replace D and compared results with TG220 and a second method proposed by Huda et al, for the same set of CT studies.
The results showed comparable behavior for all methods. There is overall agreement especially between this study and TG220. Largest differences were +13.3% and+15.9% from TG220 and Huda values, respectively. Patient size correlation showed strong correlation with the TG220 and Huda et al methods.
A simple, quick manual method to estimate CT patient radiation dose in terms of SSDE was proposed as an alternative where sophisticated computer programming is not available. It can be readily used during any clinical chest CT scanning.
The paper is novel as it presents simple, quick manual method to estimate CT patient radiation dose in chest imaging. The process can be used as alternative in cases no sophisticated computer programming is available.
美国医学物理学家协会（AAPM）工作组（TG）204 和 220 引入了一种通过引入大小特异性剂量估计（SSDE）来估计患者剂量的方法。他们提供了患者大小特异性转换因子，可以应用于容积 CT 剂量指数（CTDI），根据有效直径（D）或水当量直径（D），以 SSDE 来估计患者剂量。我们的研究提出了一种替代方法，用于在日常临床胸部 CT 中手动估计 SSDE，该方法易于使用，不需要复杂的计算机编程。
对 16 名接受胸部 CT 检查的成年患者，该方法采用平均相对电子密度（ρ=0.3）用于肺组织，ρ=1.0 用于其他组织，以缩放侧厚并计算患者轴向图像上的有效侧厚。该方法估计了一个“校正”D（D）来代替 D，并将结果与 TG220 和 Huda 等人提出的第二种方法进行了比较，这些方法用于相同的 CT 研究。
所有方法的结果均表现出相似的行为。尤其是本研究与 TG220 之间存在总体一致性。与 TG220 和 Huda 值相比，最大差异分别为+13.3%和+15.9%。患者大小相关性与 TG220 和 Huda 等人的方法具有很强的相关性。
提出了一种简单、快速的手动方法，用于根据 SSDE 估计 CT 患者的辐射剂量，作为复杂计算机编程不可用时的替代方法。它可以在任何临床胸部 CT 扫描期间方便地使用。
本文新颖之处在于提出了一种简单、快速的手动方法，用于估计胸部成像中 CT 患者的辐射剂量。在没有复杂计算机编程的情况下，该过程可作为替代方法使用。
