Blackmore C C, Black W C, Dallas R V, Crow H C
Robert Wood Johnson Clinical Scholars Program, University of Washington, Seattle, USA.
Acad Radiol. 1996 Feb;3(2):103-9. doi: 10.1016/s1076-6332(05)80373-3.
We devised a prediction rule for estimating pleural effusion volume on the basis of posteroanterior and lateral chest radiographs.
A prediction rule was devised for estimating pleural effusion volume on the basis of the presence or absence of a meniscus on chest radiographs. The rule was tested and validated using separate data sets obtained from a retrospective review of patients having both a chest radiograph and computed tomography (CT) scan (the gold standard) within 24 hr of each other. The accuracy of the prediction rule and the degree of interobserver agreement between the two independent readers were determined.
For the test and validation sets, the weighted accuracies of the prediction rule were 86% and 85%, respectively. The respective weighted interobserver agreements were 97% and 88%. Pleural effusions became visible as a meniscus on the lateral chest radiograph at a volume of approximately 50 ml; at a volume of 200 ml, the meniscus could be identified on the posteroanterior radiograph. At a volume of about 500 ml, the meniscus obscured the hemidiaphragm.
The volume of a pleural effusion can be estimated from the chest radiograph appearance with a reasonable degree of accuracy.
我们基于胸部正位和侧位X线片设计了一种预测胸腔积液量的规则。
根据胸部X线片上是否存在半月形影设计了一种预测胸腔积液量的规则。使用从回顾性分析中获得的单独数据集对该规则进行测试和验证，这些患者在彼此24小时内同时进行了胸部X线片和计算机断层扫描（CT）（金标准）检查。确定了预测规则的准确性以及两位独立阅片者之间的观察者间一致性程度。
对于测试集和验证集，预测规则的加权准确率分别为86%和85%。各自的加权观察者间一致性分别为97%和88%。胸腔积液量约为50ml时，在胸部侧位X线片上可见半月形影；积液量为200ml时，在胸部正位X线片上可识别出半月形影。积液量约为500ml时，半月形影遮盖了膈肌。
根据胸部X线片表现可以较为准确地估计胸腔积液量。
