Herman P G, Drummey J, Swensson R G, Hessel S J, Balikian J P
AJR Am J Roentgenol. 1982 Mar;138(3):485-9. doi: 10.2214/ajr.138.3.485.
It has been suggested that a 350 kV technique will produce better chest radiographs than lower kilovoltage techniques. This is because the 350 kV x-ray spectrum provides better penetration of the overlying bony structures and results in a clearer delineation of the mediastinum. Fifty cases, containing 92 definite and significant abnormalities, were selected from a pool of 500 patients who had both 350 and 140 kV chest radiographs on the same day. The 50 paired films were studied at separate times by five experienced radiologists. The interpretations were analyzed for accuracy, significance, and confidence level; interpretation times and the utility of the lateral radiograph were also noted. When all the definitely and potentially significant abnormal findings were considered, the 350 kV films produced fewer true-positive reports and more false-positive reports than the 140 kV films. The receiver operating characteristic (ROC) curves, constructed from the observers' confidence ratings, were shifted toward less satisfactory performance for the 350 kV readings. When only statements about nodules and masses were considered, identical ROC curves were produced by the two techniques. Despite their potential advantages, the 350 kV films showed no diagnostic superiority over the 140 kV films.
有人提出，350千伏技术比低千伏技术能产生更好的胸部X光片。这是因为350千伏的X射线光谱能更好地穿透覆盖其上的骨骼结构，从而更清晰地勾勒出纵隔。从500名同一天拍摄了350千伏和140千伏胸部X光片的患者中选出50例，其中包含92处明确且显著的异常。这50对片子由五位经验丰富的放射科医生在不同时间进行研究。对诊断结果的准确性、显著性和置信水平进行了分析；还记录了解读时间以及侧位X光片的效用。当考虑所有明确和潜在的显著异常发现时，350千伏的片子比140千伏的片子产生的真阳性报告更少，假阳性报告更多。根据观察者的置信度评分构建的受试者工作特征（ROC）曲线显示，350千伏读数的表现向不太理想的方向偏移。当仅考虑关于结节和肿块的描述时，两种技术产生了相同的ROC曲线。尽管350千伏的片子有潜在优势，但与140千伏的片子相比，并未显示出诊断优越性。
