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<p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">CT值</strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;"><br /></strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">某物质的CT值等于该物质的衰减系数与水的吸收系数之差再与水的衰减系数相比之后乘以分度因素。物质的CT值反映物质的密度，即物质的CT值越高相当于物质密度越高。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">即CT值=α×（μm-μw）/μw</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">α为分度因数，其取值为1000时，CT值的单位为亨氏单位（Hu）。人体内不同的组织具有不同的衰减系数，因而其CT值也各不相同。按照CT值的高低分别为骨组织，软组织，脂肪，水，气体，水的CT值为0Hu左右。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">空间分辨率，密度分辨率，时间分辨率</strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">前者指影像中能够分辨的最小细节，中者指能显示的最小密度差别，后者指机体活动的最短时间间距。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><br /></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">层厚与层距</strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">前者指扫描层的厚度，后者指两层中心之间的距离。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><br /></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">部分容积效应</strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">由于每层具有一定的厚度，在此厚度内可能包括密度不同的组织，因此，每一像素的CT值，实际所代表的是单位体积内各种组织的CT值的平均数，故不能反映该组织的真实CT值。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><br /></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">窗宽与窗位</strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">由于正常或异常的组织具有不同的CT值，范围波动在－1000～+1000Hu范围内，而人类眼睛的分辨能力相对有限，因此欲显示某一组织结构的细节时，应选择适合观察该组织或病变的窗宽以及窗位，以获得最佳的显示。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><br /></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">FOV</strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">分扫描野(SFOV)和显示野（DFOV）两种，扫描野是X线扫描时的范围，显示野是数据重建形成的图像范围，扫描野大于显示野。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><br /></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">KV、mAs</strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">即管电流、管电流量，决定X线的硬度和光子数量的两种参数，增大KV值可以使X线的穿透力增加，增大mAs则增加辐射量，所以面对不同年龄，不同体型的病人时，需要选择对应的检查选项。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><br /></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">矩阵</strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">CT矩阵用于重建图像，有256x256，512x512等几种，常用的是512x512,矩阵。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><br /></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">噪声</strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">一个均匀物体被扫描。在一个确定的ROI（感兴趣区）范围内，每个像素的CT值[HU]并不相同而是围绕一个平均值波动，CT值的变化就是噪音。轴向（断层）图像的CT值呈现一定的涨落。即是说CT值仅仅作为一个平均值来看，它可能有上下的偏差，此偏差即为噪音。噪音是由辐射强度来决定的。也即是由达到探测器的X-Ray量子数来决定的。强度越大，噪音越低。图像噪音依赖探测器表面之光子通量的大小。它取决于X线管的管电压，管电流，予过滤及准直器孔径等。重建算法也影响噪音。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><br /></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><strong style="max-width: 100%; box-sizing: border-box !important; word-wrap: break-word !important;">SNR</strong></p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;">即信噪比，信号与招噪声的比值，适当减少噪声能使图像变得更佳。</p><p style="max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-family: 'Hiragino Sans GB', 'Microsoft YaHei', Arial, sans-serif; font-size: 16px; line-height: 25.6000003814697px; white-space: normal; widows: 1; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><br /></p><p style="white-space: normal; line-height: 24.381px;"><span style="color: rgb(62, 62, 62); font-family: Arial, Verdana, sans-serif; line-height: 1.75em; text-indent: 0em; max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">地址：广州市天河区银利街银利茶叶博览中心E栋4楼E4030室 </span><span style="color: rgb(62, 62, 62); font-family: Arial, Verdana, sans-serif; text-indent: 0em; max-width: 100%; font-size: 14px; line-height: 1.75em; box-sizing: border-box !important; word-wrap: break-word !important;"> </span><br /></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; line-height: 1.75em; box-sizing: border-box !important; word-wrap: break-word !important;">邮编：510507</span></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">电话：(+86)020-8722 8723 8764 5360 8764 2943 </span></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">传真：020-8722 8623</span></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">全国统一免费服务热线：400-020-6788</span></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">微信公众帐号：</span></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><img data-ratio="1" src="http://mmbiz.qpic.cn/mmbiz/dx3KibwtDhvfCZvZq5PcthnDKlnnq3AalhbichW77J3B70osicTickklZybNKUZqc44DZ0oaWaHm2p0TaA9478icwPg/640?wx_fmt=jpeg" data-type="jpeg" data-w="120" width="auto" style="box-sizing: border-box !important; word-wrap: break-word !important; visibility: visible !important; width: auto !important;" /></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">维修咨询：QQ: 712638 404</span></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">设备咨询: QQ: 712638 405</span></p><p style="font-size: 16px; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); line-height: 24.381px; text-align: justify; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="font-size: 14px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; text-indent: 0em;">软件咨询：QQ: 712638 406</span><br /></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">配件咨询：QQ: 712638 407</span></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">交流Q群：1106 11074</span></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">网址：http://www.yiliaoshebeiweixiu.com</span></p><p style="text-indent: 0em; white-space: normal; max-width: 100%; min-height: 1em; color: rgb(62, 62, 62); font-size: 12px; font-family: Arial, Verdana, sans-serif; line-height: 1.75em; background-color: rgb(255, 255, 255); box-sizing: border-box !important; word-wrap: break-word !important;"><span style="max-width: 100%; font-size: 14px; box-sizing: border-box !important; word-wrap: break-word !important;">电子邮箱：service@yiliaoshebeiweixiu.com</span></p><p><br /></p>
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发表于 2020-10-19 23:29:22