Department of Radiological Technology, Tsuchiya General Hospital, Nakajima-cho 3-30, Naka-ku, Hiroshima, 730-8655, Japan; Department of Diagnostic Radiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
Department of Medical Physics, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
Radiography (Lond). 2021 Aug;27(3):840-846. doi: 10.1016/j.radi.2021.01.003. Epub 2021 Feb 3.
To compare the radiation dose, diagnostic accuracy, and the resultant ablation procedures using 80 and 120-kVp cardiac computed tomography angiography (CCTA) protocols with the same contrast-to-noise ratio in patients scheduled for atrial fibrillation (AF) ablation.
This retrospective study was performed following institutional review board approval. We divided 140 consecutive patients who had undergone CCTA using a 64-MDCT scanner into two equal groups. Standard deviation (SD) of the CT number was set at 25 Hounsfield units (HU) for the 120-kVp protocol. To facilitate a reduction in radiation dose it was set at 40 HU for the 80 kVp protocol. We compared the two protocols with respect to the radiation dose, the diagnostic accuracy for detecting left atrial appendage (LAA) thrombi, matching for surface registration, and the resultant ablation procedures.
At 120 kVp, the dose length product (DLP) was 2.2 times that at 80 kVp (1269.0 vs 559.0 mGy cm, p < 0.01). The diagnostic accuracy for thrombus detection was 100% using both protocols. There was no difference between the two protocols with respect to matching for surface registration. The protocols did not differ with respect to the subsequent time required for the ablation procedures and the ablation fluoroscopy time, and the radiation dose (p = 0.54, 0.33, and 0.32, respectively).
For the same CNR, the DLP at 80 kVp (559.0 mGy cm) was 56% of that delivered at 120 kVp (1269.0 mGy cm). There was no reduction in diagnostic accuracy.
Maintaining CNR allows for a reduction in the radiation dose without reducing the image quality.
比较辐射剂量、诊断准确性以及使用相同对比噪声比的 80 和 120 kVp 心脏 CT 血管造影 (CCTA) 方案在计划进行心房颤动 (AF) 消融的患者中的消融程序。
本回顾性研究经机构审查委员会批准后进行。我们将 140 名连续接受 64 排 MDCT 扫描仪 CCTA 的患者分为两组，每组 70 名。120 kVp 方案的 CT 数标准差 (SD) 设置为 25 个亨氏单位 (HU)。为了降低辐射剂量，80 kVp 方案将其设置为 40 HU。我们比较了两种方案的辐射剂量、检测左心耳 (LAA) 血栓的诊断准确性、表面配准的匹配程度以及最终的消融程序。
在 120 kVp 时，剂量长度乘积 (DLP) 是 80 kVp 的 2.2 倍 (1269.0 对 559.0 mGy·cm，p<0.01)。两种方案的血栓检测诊断准确性均为 100%。两种方案在表面配准的匹配程度上没有差异。两种方案在随后的消融程序所需时间和消融透视时间以及辐射剂量方面没有差异 (p=0.54、0.33 和 0.32)。
对于相同的 CNR，80 kVp (559.0 mGy·cm) 的 DLP 为 120 kVp (1269.0 mGy·cm) 的 56%。诊断准确性没有降低。
在保持 CNR 的情况下，降低辐射剂量而不降低图像质量。
