From the Department of Radiology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871, Japan (H.O., M.H., T.O., A.N., K.O., M.T., H.F., N.T.); Canon Medical Systems, Otawara, Japan (S.T., A.U., Y.S., A.T.); and Division of Radiology, Department of Medical Technology, Osaka University Hospital, Suita, Japan (Y.E., K.S.).
Radiology. 2018 Oct;289(1):255-260. doi: 10.1148/radiol.2018180188. Epub 2018 Jun 26.
Purpose To examine the diagnostic performance of high-spatial-resolution (HSR) CT with 0.25-mm section thickness for evaluating renal artery in-stent restenosis. Materials and Methods A 0.05-mm wire phantom and vessel phantoms with renal stents with in-stent stenotic sections of varying diameters were scanned with both an HSR CT scanner equipped with 160-section multi-detector rows (0.25-mm section thickness) and a conventional CT scanner. The wire phantom was used to analyze modulation transfer function (MTF). With the vessel phantoms, the error rates were calculated as the absolute difference between the measured diameters and true diameters divided by the true diameters at the narrowing sections. For qualitative evaluation, overall image quality and diagnostic accuracy for evaluating stenosis in three stages were assessed by two radiologists. Statistical analyses included the paired t test, Wilcoxon signed-rank test, and McNemar test. Results HSR CT achieved 24.3 line pairs per centimeter ± 0.5 (standard deviation) and 29.1 line pairs per centimeter ± 0.4 at 10% and 2% MTF, respectively; and conventional CT was 12.5 line pairs per centimeter ± 0.1 and 14.3 line pairs per centimeter ± 0.1 at 10% and 2% MTF, respectively. The mean error rate of the measured diameter at HSR CT (8.0% ± 5.8) was significantly lower than that at at conventional CT (16.9% ± 9.3; P < .001). Image quality at HSR CT was significantly better than that at conventional CT (P < .001), but HSR CT was not significantly superior to conventional CT in terms of diagnostic accuracy. Conclusion Compared with conventional CT, high-spatial-resolution CT achieved spatial resolutions of up to 29 line pairs per centimeter at 2% modulation transfer function and yielded improved measurement accuracy for the evaluation of in-stent restenosis in a phantom study of renal artery stents. Published under a CC BY 4.0 license.
探讨 0.25mm 层厚高空间分辨率（HSR）CT 评估肾动脉支架内再狭窄的诊断性能。
采用配备 160 层多探测器排（0.25mm 层厚）的 HSR CT 扫描仪和常规 CT 扫描仪对 0.05mm 金属丝 phantom 和具有不同直径支架内狭窄节段的血管 phantom 进行扫描。金属丝 phantom 用于分析调制传递函数（MTF）。血管 phantom 用于测量狭窄节段的测量直径与真实直径之间的绝对差值，并将其除以真实直径，以计算出误差率。两位放射科医师对整体图像质量和三个狭窄程度分期的诊断准确性进行定性评估。统计分析包括配对 t 检验、Wilcoxon 符号秩检验和 McNemar 检验。
HSR CT 在 10%和 2%调制传递函数时分别达到 24.3 线对/厘米±0.5（标准差）和 29.1 线对/厘米±0.4；常规 CT 分别达到 12.5 线对/厘米±0.1 和 14.3 线对/厘米±0.1。HSR CT 测量直径的平均误差率（8.0%±5.8）明显低于常规 CT（16.9%±9.3；P<0.001）。HSR CT 的图像质量明显优于常规 CT（P<0.001），但在诊断准确性方面，HSR CT 并不优于常规 CT。
与常规 CT 相比，高空间分辨率 CT 在 2%调制传递函数时可达到高达 29 线对/厘米的空间分辨率，并在肾动脉支架的血管 phantom 研究中提高了支架内再狭窄评估的测量准确性。
本研究已在知识共享署名 4.0 许可协议下发布，允许在任何媒体上以任何形式复制、发布、传播本作品。
