Stein P D, Henry J W, Gottschalk A
Henry Ford Heart and Vascular Institute, Detroit.
Chest. 1993 Nov;104(5):1468-71. doi: 10.1378/chest.104.5.1468.
The purpose of this investigation was to test the hypothesis that ventilation/perfusion (V/Q) lung scans in patients with suspected acute pulmonary embolism (PE) can be evaluated on the basis of the total number of mismatched vascular defects, irrespective of whether such defects are moderate or large size segmental defects. Lung scan data from the national collaborative study of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) were assessed in 383 patients with acute PE and 681 patients in whom suspected PE was excluded. The predictive value of the cumulative number of mismatched moderate size segmental defects (irrespective of the number of mismatched large segmental defects) was nearly the same as that of mismatched large segmental defects (irrespective of the number of mismatched moderate size segmental defects). This suggests that the diagnostic value of mismatched moderate size segmental defects is the same as mismatched large segmental defects. Lung scans evaluated on the basis of the number of mismatched vascular defects (moderate and/or large segmental defects) were compared with V/Q scans evaluated on the basis of the number of mismatched segmental equivalents. The maximum likelihood estimates of the areas under the receiver operating characteristic (ROC) curves for the number of mismatched vascular defects and for mismatched segmental equivalents were similar (0.8512 vs 0.8530) (NS). Stratification according to the presence or absence of prior cardiopulmonary disease permitted a more accurate assessment of both clinical groups. Evaluation of V/Q scans by vascular defects and by segmental equivalents showed similar areas under the ROC curves. In conclusion, the number of mismatched vascular defects is as powerful for the assessment of V/Q scans as the number of mismatched segmental equivalents. The number of mismatched vascular defects, however, is easier to interpret, and permits a more objective evaluation.
对于疑似急性肺栓塞（PE）的患者，通气/灌注（V/Q）肺扫描可根据不匹配血管缺损的总数进行评估，而不论这些缺损是中度还是大尺寸节段性缺损。对来自肺栓塞诊断前瞻性调查（PIOPED）全国协作研究的肺扫描数据进行了评估，涉及383例急性PE患者和681例排除疑似PE的患者。中度大小节段性不匹配缺损的累积数量（不论大节段性不匹配缺损的数量）的预测价值与大节段性不匹配缺损（不论中度大小节段性不匹配缺损的数量）的预测价值几乎相同。这表明中度大小节段性不匹配缺损的诊断价值与大节段性不匹配缺损相同。将基于不匹配血管缺损数量（中度和/或大节段性缺损）评估的肺扫描与基于不匹配节段等效物数量评估的V/Q扫描进行比较。不匹配血管缺损数量和不匹配节段等效物数量的受试者操作特征（ROC）曲线下面积的最大似然估计相似（0.8512对0.8530）（无显著性差异）。根据有无既往心肺疾病进行分层，可对两个临床组进行更准确的评估。通过血管缺损和节段等效物对V/Q扫描进行评估，ROC曲线下面积相似。总之，不匹配血管缺损的数量在评估V/Q扫描方面与不匹配节段等效物的数量同样有效。然而，不匹配血管缺损的数量更易于解释，并且允许进行更客观的评估。
