Stein P D, Relyea B, Gottschalk A
Henry Ford Heart and Vascular Institute, Detroit, Michigan 48202-2691, USA.
J Nucl Med. 1996 Apr;37(4):577-81.
The purpose of this investigation was to identify characteristics or combinations of characteristics of the ventilation-perfusion (V/Q) scan in patients with suspected acute pulmonary embolism (PE) can be used for a "very low probability" interpretation ( < 10% positive predictive value).
Data were culled from individual lungs of 532 patients in the randomized arm of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study and 205 patients in the referred arm. All patients had a < 20% consensus probability estimate of PE based on V/Q scan results, and all underwent pulmonary angiography.
Nonsegmental perfusion abnormalities, perfusion defects smaller than opacities on the chest radiograph, a combination of these types of perfusion abnormalities, and matched V/Q abnormalities in two or three zones of a single lung had a positive predictive value < 10%. These criteria can therefore be used for a very low probability interpretation. A matched V/Q defect in only one zone of the lung had a positive predictive value greater than 10% and is not a criterion for low probability. Perfusion defects associated with small pleural effusions (obliteration of the costophrenic angle) had a positive predictive value of 25%-33%, depending on the group studied, and are a criterion for intermediate probability.
Criteria appropriate for a very low probability ( < 10% positive predictive value) interpretation of V/Q scans in patients with suspected acute PE have been identified.
本研究的目的是确定疑似急性肺栓塞（PE）患者通气-灌注（V/Q）扫描的特征或特征组合，这些特征可用于“极低概率”的解读（阳性预测值<10%）。
数据来自肺栓塞诊断前瞻性研究（PIOPED）随机分组组的532例患者以及转诊组的205例患者的单肺情况。所有患者基于V/Q扫描结果对PE的共识概率估计<20%，且均接受了肺血管造影。
非节段性灌注异常、小于胸部X线片上不透光区的灌注缺损、这些类型灌注异常的组合以及单肺两到三个区域的匹配V/Q异常，其阳性预测值<10%。因此，这些标准可用于极低概率的解读。仅在肺的一个区域出现的匹配V/Q缺损，其阳性预测值大于10%，并非低概率的标准。与小量胸腔积液（肋膈角消失）相关的灌注缺损，根据所研究的组不同，阳性预测值为25%-33%，是中度概率的标准。
已确定适用于对疑似急性PE患者V/Q扫描进行极低概率（阳性预测值<10%）解读的标准。
