排序方式: 共有77条查询结果,搜索用时 0 毫秒
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目的探讨低剂量CT扫描在新型冠状病毒肺炎(COVID-19)的应用价值。方法回顾性分析2020年2月1日至22日首次在本院接受MSCT胸部扫描的200例COVID-19确诊患者的影像资料,常规剂量组(150 mA)和低剂量组(50 mA)各100例。两组数据传至工作站进行多平面重组(MPR)。由2名高年资影像诊断医师独立阅片并对COVID-19患者进行分期和评分,分别记录常规剂量组和低剂量组剂量长度乘积(DLP)、CT容积剂量指数(CTDIvol),计算有效辐射剂量(ED)。在我院治愈复查患者41例,其中低剂量组20例、常规剂量组21例,CT检查次数平均为(4±1)次,分别记录每例患者总DLP、总ED。结果首次检查患者,常规剂量组和低剂量组对不同时期COVID-19患者检出率结果无统计学差异(P=0.216);两组图像评分均值分别为2.70±0.52和2.52±0.66,结果无统计学差异(P=0.168);常规剂量组CTDIvol、DLP、ED分别为(9.73±1.5)mGy、(380.22±20.55) mGy·cm和(5.32±0.90) mSv;低剂量组分别为(3.81±0.88... 相似文献
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多层螺旋CT多平面重组对孤立性肺结节征象检出的价值 总被引:1,自引:0,他引:1
目的:比较多层螺旋CT多平面重组(MPR)对孤立性肺结节(SPNs)征象的显示,探讨各种征象对SPNs良恶性的诊断价值.方法:搜集51例进行多层螺旋CT扫描的SPNs (直径≤4 cm)及其完整的临床病理资料.对SPNs的征象(深分叶征、棘状突起征、胸膜凹陷征、胸膜切迹征、阳性支气管征、空泡征、毛刺征)行MPR,评价MPR对SPNs的前5种征象的显示.计算7种征象在恶性结节组检出率及出现频率.结果:MPR检出5种征象的数目明显多于轴面扫描所检出的数目,检出具有5种征象的结节数目明显多于轴面扫描检出该征象的结节数目,差异具有显著性意义(P<0.05).在恶性结节中出现频率由多到少的征象依次为深分叶征、阳性支气管征、胸膜凹陷征、棘状突起征、胸膜切迹征、毛刺征、空泡征.7种征象在良、恶性结节组的检出百分比中最能提示恶性的征象依次为胸膜切迹征、深分叶征、胸膜凹陷征、毛刺征、阳性支气管征、棘状突起征、空泡征.结论:应用多层螺旋CT薄层扫描,对SPNs行MPR,能明显提高SPNs的征象检出率,获得更多有价值的诊断信息,深分叶征、胸膜切迹征是最有诊断价值的恶性征象. 相似文献
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目的 对新型冠状病毒肺炎放射诊断场所存在的感染控制和辐射安全风险进行调查和监测,为放射技师及相关工作人员的安全防护提供数据支持。方法 根据国家标准(WS 519-2019和GBZ 130-2013)对湖北省4所未启用的应急医院("小汤山式"甲、乙医院及方舱医院、砖混模式医院)中新安装的8台CT及其场所进行成像性能和放射防护检测并评价。对机房布局等感染控制安全的因素实施了监测与调查。选择定点医院2所(综合医院和传染病专科医院),通过现场调查和对4个CT机房环境生物样本进行新型冠状病毒核酸检测,对放射场所的布局、感染防控和核酸检测结果的分布进行分析,评价其生物安全的可靠性和风险点。结果 应急医院的8台CT设备的成像性能和放射防护指标均能满足国家标准的要求。甲、乙医院各有3个CT机房,面积均为38.8 m2和4 mm Pb当量的屏蔽防护;方舱医院和砖混建筑医院的CT机房面积和屏蔽防护分别为20.0 m2、4 mm Pb当量和35.8 m2、3 mm Pb当量。8个放射诊断场所符合感染防控"三区两通道"的设计要求。新型冠状病毒核酸检测结果显示,CT机房内患者触碰到的多个位点如检查床、机架内侧、地面等多处发现核酸阳性。放射技师通过手部、足底沾染造成操作间内操作台和地面的病毒污染风险。此外,机房内患者未触及的区域如观察窗和排风口等处也出现类似阳性。结论 4所应急医院的8台CT设备和机房基本满足成像性能和放射防护要求。新型冠状病毒肺炎放射诊断检查场所需加强消毒的规范化。 相似文献
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The influence of low tube voltage in dual source CT(DSCT) coronary artery imaging on image quality and radiation dose and its application value in clinical practice were investigated. Totally, 300 cases of chest pain with low body mass index(BMI 〈18.5 kg/m2) subjected to DSCT coronary artery imaging were prospectively enrolled. The heart rate in all patients were greater than 65/min. The retrospective ECG gated scanning mode and simple random sampling method were used to assign the patients into groups A, B and C(n=100 each). The patients in groups A, B and C experienced 120-, 100-, and 80-kV tube voltage imaging respectively, and the image quality was evaluated. The CT volume dose index(CTDIvol) and dose length product(DLP) were recorded, and the effective dose(ED) was calculated in each group. The image quality scores and radiation doses in groups were compared, and the influence of tube voltage on image quality and radiation dose was analyzed. The results showed that the excellent rate of image quality in groups A, B and C was 95.69%, 94.72% and 96.33% respectively with the difference being not statistically significant among the three groups(P〉0.05). The CTDIvol values in groups A, B and C were 51.35±12.21, 21.28±7.13 and 6.34±3.34 mGy, respectively, with the difference being statistically significant(P〈0.05). The ED values in groups A, B and C were 9.27±1.63, 4.56±2.29 and 2.29±1.69 mSv, respectively, with the difference being statistically significant(P〈0.05). It was suggested that for the patients with low BMI, the application of DSCT coronary artery imaging with low tube voltage can obtain satisfactory image quality, and simultaneously, significantly reduce the radiation dose. 相似文献
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CT在腰椎疾病检查中发挥着重要作用,已成为腰椎各种疾病的重要检查手段.但据文献报道,采用与椎间盘层面平行的逐层扫描技术有10%~20%的误、漏诊率,特别对早期椎体峡部及椎管病变等漏诊率更高.多层螺旋CT(MSCT)弥补了以往常规CT的不足,改变了CT对腰椎的扫描方法及诊断方法,提高了诊断的准确率[1-2].本研究通过比较两种扫描方法的辐射剂量以及对腰椎图像质量的影响,探讨16层螺旋CT腰椎扫描方法与辐射剂量之间的关系. 相似文献