Electron-beam CT: use of a calibration phantom to reduce variability in calcium quantitation.
Electron-beam CT: use of a calibration phantom to reduce variability in calcium quantitation.
复制标题
电子束 CT：使用校准模型来减少钙定量的变异性。
DOI：
10.1148/radiology.196.1.7784560
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发表时间：
1995
期刊：
影响因子：
19.7
通讯作者：
Peyser,PA
中科院分区：
文献类型：
--
作者：
McCollough,CH;Kaufmann,RB;Cameron,BM;Katz,DJ;Sheedy2nd,PF;Peyser,PA
目的测量电子束CT扫描仪和患者在计算机断层扫描（CT）数量上的变化，并确定校正幻影减少钙定量变化的能力。材料与方法对2个校准幻象进行成像，以确保纵向均匀性，并确定扫描内CT数的短期变化。每个幻像组每天成像两次，持续14周，以确定扫描仪内和扫描仪间的变化。167例包括幻肢在内的患者的检查数据进行了分析，以确定已知钙浓度的物体CT数量在患者内部和患者之间的变化。结果校正后的扫描仪误差减少了约25%。与130 HU CT数相关的钙浓度在77.1 - 136.4 mg/cm3之间变化，与患者的腰围、性别、吸烟史和图像水平有关。结论电子束CT的校正模体可以减少扫描仪和患者在CT数上的差异。体外和体内钙浓度的估计精度分别为2%和7%。
PURPOSETo measure scanner and patient variation in computed tomographic (CT) numbers for electron-beam CT and to determine the ability of calibration phantoms to reduce variability in calcium quantitation.MATERIALS AND METHODSTwo calibration phantoms were imaged to ensure longitudinal homogeneity and to determine the short-term intrascanner variation in CT numbers. Each phantom set was imaged twice a day for 14 weeks to determine intra- and interscanner variation. Data from examinations of 167 patients that included the phantom were analyzed to determine the intra- and interpatient variation in CT numbers of objects with known calcium concentrations.RESULTSThe calibration reduced scanner variations by approximately 25%. The calcium concentration associated with a CT number of 130 HU varied from 77.1 to 136.4 mg/cm3 and was dependent on patient girth, sex, smoking history, and image level.CONCLUSIONScanner and patient variations in CT numbers in electron-beam CT can be reduced with a calibration phantom. In vitro and in vivo estimates of calcium concentration had a precision of 2% and 7%, respectively.