Dual-Energy CT Material Density Iodine Quantification for Distinguishing Vascular From Nonvascular Renal Lesions: Normalization Reduces Intermanufacturer Threshold Variability
Dual-Energy CT Material Density Iodine Quantification for Distinguishing Vascular From Nonvascular Renal Lesions: Normalization Reduces Intermanufacturer Threshold Variability
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DOI：
10.2214/ajr.18.20115
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发表时间：
2019-02-01
影响因子：
5
通讯作者：
Marin, Daniele
中科院分区：
文献类型：
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作者：
Patel, Bhavik N.;Vernuccio, Federica;Marin, Daniele
目标。本研究的目的是确定单一的、统一的标准化碘阈值是否可以减少变异性，并能够独立于所使用的双能CT （DECT）平台可靠地区分血管性和非血管性肾脏病变。材料和方法。在这项回顾性研究中，247名患者（156名男性，91名女性，平均年龄+/- SD， 67 +/- 12岁）263个肾脏病变（193个非血管病变，70个血管病变）接受了未增强的单能量和增强的DECT扫描。在两台双源DECT （dsDECT）扫描仪上扫描了106个非血管病变和38个血管病变，在两台快速千压开关单源DECT （rsDECT）扫描仪上扫描了87个非血管病变和32个血管病变。确定了每种平台类型和整个队列的最佳绝对和标准化（到主动脉）病变碘阈值。dsDECT、rsDECT和联合队列的平均最佳绝对判别阈值分别为1.3 mg I/mL （95% CI, 1.21.9 mg I/mL）、1.6 mg I/mL （95% CI, 0.91.5 mg I/mL）和1.5 mg I/mL （95% CI, 1.41.7 mg I/mL）。dsDECT和rsDECT队列的最佳归一化判别阈值均为0.3 mg I/mL (95% CI, 0.20.4 mg I/mL)，联合队列的最佳归一化判别阈值为0.3 mg I/mL （0.30.4 mg I/mL）。组合最佳归一化判别阈值0.3 mg I/mL的AUC、灵敏度和特异性分别为0.96 （95% CI, 0.921.00）、0.93（0.840.97）和0.95（0.910.98）。归一化导致变异性降低和更好的病变分离（效应值，1.77 vs 1.69, p < 0.0001）。评估肾脏病变的最佳绝对判别阈值取决于DECT平台的类型，尽管这种差异没有统计学意义。通过使主动脉碘定量正常化，可以更好地分离血管和非血管病变，从而减少变异。
OBJECTIVE. The purpose of this study was to determine whether a single, uniform normalized iodine threshold reduces variability and enables reliable differentiation between vascular and nonvascular renal lesions independent of the dual-energy CT (DECT) platform used.MATERIALS AND METHODS. In this retrospective, HIPAA-compliant, institutional review boardapproved study, 247 patients (156 men, 91 women; mean age +/- SD, 67 +/- 12 years old) with 263 renal lesions (193 nonvascular, 70 vascular) underwent unenhanced single-energy and contrast-enhanced DECT scans. One hundred and six nonvascular and 38 vascular lesions were scanned on two dual-source DECT (dsDECT) scanners, and 87 nonvascular and 32 vascular lesions were scanned on two rapid-kilovoltage-switching single-source DECT (rsDECT) scanners. Optimal absolute and normalized (to aorta) lesion iodine thresholds were determined for each platform type and for the entire cohort combined.RESULTS. Mean optimal absolute discriminant thresholds were 1.3 mg I/mL (95% CI, 1.21.9 mg I/mL), 1.6 mg I/mL (95% CI, 0.91.5 mg I/mL), and 1.5 mg I/mL (95% CI, 1.41.7 mg I/mL) for dsDECT, rsDECT, and combined cohorts, respectively. Optimal normalized discriminant thresholds were 0.3 mg I/mL (95% CI, 0.20.4 mg I/mL) for both the dsDECT and rsDECT cohorts, and 0.3 mg I/mL (0.30.4 mg I/mL) for the combined cohort. The AUC, sensitivity, and specificity for the combined optimal normalized discriminant threshold of 0.3 mg I/mL was 0.96 (95% CI, 0.921.00), 0.93 (0.840.97), and 0.95 (0.910.98), respectively. Normalization resulted in decreased variability and better lesion separation (effect size, 1.77 vs 1.69, p < 0.0001).CONCLUSION. The optimal absolute discriminant threshold for evaluating renal lesions varies depending on the type of DECT platform, though this difference is not statistically significant. Variation can be reduced with a better separation of vascular and nonvascular lesions by normalizing iodine quantification to the aorta.