Los Angeles Biomedical Research Institute, Harbor-UCLA Medical Center, 1124 W Carson St, Torrance, CA 90502-2006, USA.
Radiology. 2013 Jun;267(3):830-6. doi: 10.1148/radiol.13111987. Epub 2013 Feb 25.
To determine the accuracy and precision of thoracic phantomless bone mineral density (BMD) measurements obtained on coronary artery calcium (CAC) computed tomography (CT) scans by using a variety of commercially available CT scanners.
The institutional review board approved this Health Insurance Portability and Accountability Act-compliant study. A total of 4126 asymptomatic subjects (2022 [49%] men, 2104 [51%] women; mean age, 63.7 years ± 11.8 [standard deviation]) underwent CAC CT with the use of a quantitative CT calibration phantom for evaluation of subclinical atherosclerosis. Two hundred eighty subjects also underwent CT of the chest, abdomen, and pelvis (C7 through L5). Mean BMD of three consecutive thoracic vertebrae (in the T7-T10 range) was measured in all 4126 subjects. Individual calibration factors for each phantom insert and a general calibration factor for the spine were determined for each CT scanner model. The study population was then divided into three subgroups: All calibration factors were generated from group 1 (n = 1536) and were applied and tested in group 2 (n = 1587), and effects of various image acquisition parameters were assessed in group 3 (n = 1003). Accuracy (bias) and precision of thoracic phantomless BMD measurements across 14 CT scanner models from five manufacturers were determined.
Phantomless BMD values correlated highly with standard phantom-based quantitative CT BMD values (r = 0.987, P < .001). Bias was 3.9% ± 1.4 for phantomless BMD measurements, and the mean coefficient of variation for the general calibration factor was 4.9% ± 2.4.
Phantomless BMD can be measured accurately on CAC CT scans acquired with a variety of CT scanners without additional radiation exposure.
使用各种市售 CT 扫描仪，确定冠状动脉钙化 (CAC) CT 扫描中获得的无胸模骨密度 (BMD) 测量的准确性和精密度。
本研究经机构审查委员会批准，符合《健康保险流通与责任法案》。共纳入 4126 名无症状受试者（2022 名男性[49%]，2104 名女性[51%]；平均年龄 63.7 岁±11.8[标准差]），进行 CAC CT 扫描，使用定量 CT 校准模体评估亚临床动脉粥样硬化。280 名受试者还进行了胸部、腹部和骨盆 CT（C7 至 L5）。4126 名受试者均测量三个连续胸椎（T7-T10 范围内）的平均 BMD。为每个 CT 扫描仪模型确定了每个模体插入物的个体校准因子和脊柱的一般校准因子。然后将研究人群分为三组：组 1（n=1536）生成所有校准因子，并将其应用于组 2（n=1587）并进行测试，在组 3（n=1003）中评估各种图像采集参数的影响。确定了来自五家制造商的 14 种 CT 扫描仪模型的无胸模 BMD 测量的准确性（偏差）和精密度。
无胸模 BMD 值与基于标准模体的定量 CT BMD 值高度相关（r=0.987，P<0.001）。无胸模 BMD 测量的偏差为 3.9%±1.4%，通用校准因子的平均变异系数为 4.9%±2.4%。
在不增加额外辐射暴露的情况下，可在各种 CT 扫描仪上准确测量 CAC CT 扫描中的无胸模 BMD。
