Kliewer M A, Tupler R H, Hertzberg B S, Paine S S, DeLong D M, Svetkey L P, Carroll B A
Department of Radiology, Duke University Medical Center, Durham, NC 27710.
AJR Am J Roentgenol. 1994 Jun;162(6):1371-6. doi: 10.2214/ajr.162.6.8192002.
Analysis of Doppler waveform morphology for features of the tardus-parvus phenomenon has been promoted as a useful and accurate means for detecting renal artery stenosis. The purpose of this study was to examine and quantify the interobserver agreement of such an analysis and to determine if interobserver differences limit the value of this approach for predicting renal artery stenosis.
Four observers independently categorized renal artery waveforms of 47 patients (94 kidneys) clinically selected for renovascular hypertension. Waveforms were classified into five categories based on the presence and severity of tardus-parvus changes in the systolic upstroke and early systolic peak. This categorization was then compared with angiographic findings, and the results were analyzed with receiver-operating-characteristic curves. Kappa statistics and agreement tables were computed to evaluate interobserver agreement.
Interobserver agreement in the waveform analysis for the four interpreters was statistically significant (p < 0.001). The receiver-operating-characteristic areas produced by the observers indicated, however, that such waveform classification was not strongly predictive of renal artery stenosis.
We conclude that substantial agreement in the interpretation of waveform morphology can be obtained between independent observers, and that such differences that do exist do not preclude the use of the pattern-recognition approach to waveform analysis. Even so, the specific application of this strategy to the waveform contours of early systole was not successful in predicting the presence or severity of renal artery stenosis.
对多普勒波形形态进行迟滞-低平现象特征分析，已被推崇为检测肾动脉狭窄的一种有用且准确的方法。本研究的目的是检验并量化这种分析在观察者间的一致性，并确定观察者间的差异是否限制了这种方法在预测肾动脉狭窄方面的价值。
四名观察者独立对47例因肾血管性高血压而入选临床研究的患者（94个肾脏）的肾动脉波形进行分类。根据收缩期上升支和收缩早期峰值中迟滞-低平变化的存在情况及严重程度，将波形分为五类。然后将这种分类结果与血管造影结果进行比较，并使用受试者操作特征曲线对结果进行分析。计算kappa统计量和一致性表格以评估观察者间的一致性。
四名解释者在波形分析中的观察者间一致性具有统计学意义（p < 0.001）。然而，观察者得出的受试者操作特征曲线面积表明，这种波形分类对肾动脉狭窄的预测性不强。
我们得出结论，独立观察者之间在波形形态解释方面可达成实质性一致，并且即使存在差异也不排除使用模式识别方法进行波形分析。即便如此，将这种策略具体应用于收缩早期的波形轮廓，在预测肾动脉狭窄的存在或严重程度方面并不成功。
