膝关节双能量CT低剂量扫描对虚拟去钙图像质量及骨挫伤诊断的影响

发布时间：2018-08-03 20:17

【摘要】：目的评估膝关节双能量CT(DECT)低辐射剂量扫描对虚拟去钙(VNCa)图像质量及骨挫伤诊断的影响。方法对60例膝关节骨挫伤患者行DECT和MRI检查,按DECT扫描剂量分为常规剂量组(A球管60 m As/rot,B球管255 m As/rot)(A组,32例)和低剂量组(A球管42 m As/rot,B球管178 m As/rot)(B组,28例)。评估两组的VNCa图像质量,并对骨髓损伤进行分级,以MR图像为参考标准,比较两组VNCa图像诊断骨挫伤的预测值。结果 A组中,VNCa图像质量评分为优秀、一般和差者分别为26、6和0例,B组分别为19、9和0例,两组差异无统计学意义(P=0.236)。A组和B组辐射剂量长度乘积分别为(204.28±29.02)m Gy·cm和(136.61±16.74)m Gy·cm,与A组相比,B组的辐射剂量下降33.1%。A组中,VNCa图像诊断股骨下端骨挫伤的敏感性、特异性、阳性预测值和阴性预测值分别为73.5%、98.6%、94.7%和91.6%,胫骨上端相应预测值分别为91.0%、100.0%、100.0%和95.4%;B组中,股骨下端相应各值分别为69.1%、98.2%、95.0%和86.7%,胫骨上端各值分别为88.2%、97.0%、95.2%和92.4%;各项预测值两组间比较差异均无统计学意义(P值均0.05)。结论 DECT低辐射剂量(A球管42 m As/rot,B球管178 m As/rot)扫描对VNCa图像质量及骨挫伤诊断无影响。
[Abstract]:Objective to evaluate the effect of dual energy CT (DECT) low dose scanning on the quality of virtual decalcified (VNCa) and the diagnosis of bone contusion. Methods DECT and MRI were performed in 60 patients with bone contusion of the knee joint. According to the DECT scanning dose, they were divided into two groups: the normal dose group (A balloon tube 60 m as / R B balloon tube 255 m As/rot) (A group, 32 cases) and the low dose group (A ball tube 42 m as / R B balloon tube 178 m As/rot) (B group, 28 cases). The quality of VNCa images in the two groups was evaluated and the bone marrow injuries were graded. The predictive values of bone contusion diagnosed by Mr images were compared between the two groups. Results in group A, the image quality score of VNCa was excellent, the average and poor image quality of group B and group B were 26 / 6 and 19 / 9, respectively. There was no significant difference between the two groups (P < 0. 236). The product of radiation dose length in group A and group B were (204.28 卤29.02) m Gy cm) and (136.61 卤16.74) m Gy cm,), respectively. The sensitivity and specificity of VNCa images in diagnosing bone contusion of lower femur in group A and group A were 33.1% lower than those in group A (136.61 卤16.74) m Gy cm,), respectively. The positive predictive value and the negative predictive value were 73.5% and 91.6%, respectively. The corresponding predictive values at the upper tibia were 91.0% and 100.0% and 95.4%, respectively. The corresponding values at the lower end of the femur were 69.1% and 86.7%, respectively, and those at the upper end of the tibia were 88.2and 97.0% and 92.4%, respectively, and there was no significant difference between the two groups (P 0.05). Conclusion low radiation dose of DECT (A tube 42 m as / R B tube 178 m As/rot) has no effect on the quality of VNCa image and the diagnosis of bone contusion.
【作者单位】：解放军第一六一医院放射科;华中科技大学同济医学院附属协和医院放射科;
【分类号】：R684;R816.8

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