Hendel R C, Parker M A, Wackers F J, Rigo P, Lahiri A, Zaret B L
Department of Medicine, Northwestern University Medical School, Chicago, Ill. 60015, USA.
J Nucl Cardiol. 1994 Nov-Dec;1(6):509-14. doi: 10.1007/BF02939973.
The purpose of this study was to determine the relative image quality and interobserver variability among four readers for 201Tl and 99mTc-labeled tetrofosmin myocardial perfusion images. 99mTc-labeled perfusion agents, with near-optimal physical characteristics for gamma camera imaging, may allow for superior image quality and improved consistency of interpretation. However, most studies to date have demonstrated only similarity in the diagnostic accuracy between technetium agents and thallium. Tetrofosmin is a recently developed 99mTc-labeled agent that has shown promising results in early clinical trials.
A multicenter, open-label trial was performed during which treadmill exercise thallium and tetrofosmin scintigraphy was performed within a 2-week period of each other in 216 subjects. Image quality was evaluated subjectively and scans were interpreted in a blinded, independent fashion by four readers. Perfusion abnormalities were graded as consistent with ischemia, infarction, or mixed and were described both globally and regionally. Interobserver variability was assessed by use of the kappa statistic, and receiver-operator curves were compared for each observer for the diagnostic accuracy of each agent. More tetrofosmin images were of excellent quality than with thallium (52% vs 28%; p < 0.05), and when differences in quality were noted between the agents, tetrofosmin was more often superior (p < 0.0001). The interobserver variability was lower with tetrofosmin scintigraphy because generally higher kappa values were noted, especially in the lateral wall. Higher receiver-operator curve areas indicative of improved diagnostic accuracy were noted among the four readers for tetrofosmin in 80% of vascular territories.
99mTc-labeled tetrofosmin scintigraphy yields images of improved quality compared with thallium, and there is an overall improvement in the consistency of image analysis associated with the use of tetrofosmin.
本研究的目的是确定四位阅片者对201Tl和99mTc标记的替曲膦心肌灌注图像的相对图像质量及观察者间的变异性。99mTc标记的灌注剂具有近乎最佳的γ相机成像物理特性，可能会带来更高的图像质量和更好的解读一致性。然而，迄今为止的大多数研究仅表明锝剂和铊剂在诊断准确性上相似。替曲膦是一种最近研发的99mTc标记剂，在早期临床试验中已显示出有前景的结果。
进行了一项多中心、开放标签试验，在此试验中，216名受试者在彼此相隔2周的时间内分别进行了跑步机运动铊和替曲膦闪烁扫描。主观评估图像质量，扫描结果由四位阅片者以盲法、独立方式进行解读。灌注异常被分级为与缺血、梗死或混合情况相符，并从整体和局部进行描述。通过使用kappa统计量评估观察者间的变异性，并比较每位观察者对每种剂的诊断准确性的受试者操作特征曲线。与铊剂相比，替曲膦的优质图像更多（52%对28%；p<0.05），并且当注意到两种剂之间的质量差异时，替曲膦更常表现更优（p<0.0001）。替曲膦闪烁扫描观察者间的变异性更低，因为通常观察到更高的kappa值，尤其是在侧壁。在80%的血管区域中，四位阅片者对替曲膦的受试者操作特征曲线面积更高，表明诊断准确性有所提高。
与铊剂相比，99mTc标记的替曲膦闪烁扫描产生的图像质量更高，并且使用替曲膦在图像分析的一致性方面有整体改善。
