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<p class="p0" style="text-indent: 22.5pt; margin-bottom: 0pt; margin-top: 0pt; line-height: 150%;"><span style="font-size: 12pt; font-family: 宋体;"><img src="http://mmbiz.qpic.cn/mmbiz/A1DicCH9Vl6NyPYRdpyamWZASxaxvdqhrrx2z3kBCdiajEibcmQHdAOBxHIAvqsicMahHKOWc2ddsIA7mBSSjibKVgg/0" data-ratio="0.25" data-w="400" /></span></p><p class="p0" style="text-indent: 22.5pt; margin-bottom: 0pt; margin-top: 0pt; line-height: 150%;"><span style="font-size: 12pt; font-family: 宋体;">CT图像伪影指图像上与实际解剖结构不相符的密度异常变化，它涉及CT机部件故障、校准不够及算法误差甚至错误等项目，要消除此类伪影，需根据图像伪影的形状、密度变化值及扫描参数等进行具体问题具体分析。第三代CT机的图像伪影具有一定的普遍性，又特别以环状伪影为最常见，本文以GE公司氙气探测器型CT为研究对象，讨论了CT图像环状伪影的图像表现，并给出了一般的检修方法。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1 与环状伪影相关的错误信息分析</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．1 X-ray Zero Detect</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．1．1 可能故障原因按相关程度排序：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① CAM板</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 探测器</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 扁平连接电缆</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ④ CAM CONT板</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑤ ADC板</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑥ 探测器偏置电源</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑦ X射线球管</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．1．2 检修流程：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 扫一个SCOUT定位像， 不出X线，生成原始数据的平均值文件；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 显示此平均值文件中的数据，若是观察到有14个或22个通道数据不正常，则CAM板或CAM CONT板故障的可能性大；若每隔42个通道再循环，遇ADC板故障的可能性较大；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 检查探测器偏置电源保险丝没有烧断，电压输出在正常范围；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ④ 检查探测器偏置电压输入端与地的电阻大于9．5M欧。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．2 Warm Up Error“HPF”</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．2．1 可能故障原因按相关程度排序：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 探测器，最可能是信号线与地短路；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② CAM板；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 聚脂薄膜环上有吸收射线的污迹；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ④ X线球管；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑤ 准直器；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑥ X线过滤器。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．2．2 检修流程：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 检查Warm Up Error（HPF/ST）错误信息，若错误是HPF，记录HPF值超出标的通道号；若错误是ST Rate，显示最近一次探测器数值的平均值文件，并标记坏通道；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 作一次慢速扫描和一次快速扫描，看通道数据曲线图上是否有尖峰（Spike），若有，则在CAM板上交换相应通道对应的扁平电缆和邻近通道的扁平电缆，再作慢速扫描和快速扫描，若尖峰移到其它通道，则说明是探测的通道问题，若尖峰仍在原通道处，则说明是探测器后面的CAM板问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 测量环状伪影的半径；若是大面积环状伪影，则需确认探测器是36摄氏度，若不是，需检查Temp．Cont．板；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ④ 作POR和BOW测试并调整，若故障依然存在，检查X线过滤器并作间隙比率测试，若有测试有问题，则X射线路径上有灰尘或者间隙机构有问题。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．3 Warm Up Error “Please Clean Gantry Aperture”</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．1．1 可能故障部件按相关程度排序：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① X线球管，很可能球管里有气泡；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② X线路径上有吸收射线的物体。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．1．2 检修流程：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 检查清除APERTURE内的异物，若故障依旧，作静止扫描，分别在0度、180度扫描，若有一个方向出此错，则是X线球管的问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 若静止扫描均无此故障，去掉聚脂薄膜环，作轴位旋转扫描，若故障依旧，则故障可能是DAS部分的异常。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．4 Warm Up Error “ST”</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．2．1 故障部件按相关程度排序：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> 探测器，很可能是探测器通道信号线与地之间短路</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">1．2．2 检修流程：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 检查Warm Up文件，对比上次Warm Up文件，记录异常的平均值文件中的坏通道；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 作慢速扫描和快速扫描，检查坏通道处的数据是否异常，若异常，则交换相应的扁平电缆，若异常数据通道变化，确定探测器坏。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2 图像环状伪影故障检修</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．1 单通道环状伪影</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．1．1 图像表现</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><img data-s="300,640" src="http://mmbiz.qpic.cn/mmbiz/A1DicCH9Vl6NyPYRdpyamWZASxaxvdqhrPXZtqEhZmDfwU0Q1nHNtFSgoziaezZB6j94xcJILYSs3G0Xic5dcyzkw/0" data-ratio="0.9861111111111112" data-w="72" /></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．1．2 伪影原因按相关程度排序：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 探测器某个通道信号线与地短路；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 机架内部温度异常；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 探测器与球管、准直器不在同一扫描窗口，需作BOW（Beam on Window）检查；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ④ 某个通道的扁平电缆连接被损坏；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑤ CAM板问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑥ 探测器温度控制问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑦ X线过滤线问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑧ 间隙调整问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑨ X线球管问题</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．1．3 检修流程：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 查找故障信息中是否有Warm Up Error（HPF/SD）和X-ray Zero Detect Error等错误，若有，记录相应的HPF值超出标准的通道号；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 作一次慢速扫描和一次快速扫描，看通道数据曲线图上是否有尖峰（Spike），若有，则在CAM板上交换相应通道对应的扁平电缆和邻近通道的扁平电缆，再作慢速扫描和快速扫描，若尖峰移到其它通道，则说明是探测的通道问题，若尖峰仍在原通道处，则说明是探测器后面的CAM板问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 测量环状伪影的半径，若坏通道刚好在扁平电缆的边缘，则需确认探测器温度是36摄氏度且机架内部温度小于36摄氏度，若不是，确认是Temp． Cont． Board问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ④ 调整POR（Plane of Ration）和BOW（Beam on Window），重扫，若故障依旧，检查X线过滤并作准直器间隙比率测试，测试若有异常数据，说明可能是X线过滤器或准直器间隙内有灰尘或其它吸收射线的异物；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．2 环状伪影带</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．2．1 图像表现：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><img data-s="300,640" src="http://mmbiz.qpic.cn/mmbiz/A1DicCH9Vl6NyPYRdpyamWZASxaxvdqhrsZ6g1FRIsmHbUx4rOnHF0r4E4EtKvchI1KFz99LhpkTlTianNMWo3oA/0" data-ratio="0.918918918918919" data-w="74" /></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．2．2 伪影原因按相关程度排序</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① CAM板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② CAM CONT板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 准直器间隙；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ④ X线过滤器；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑤ 校准文件问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑥ X线球管。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．2．3 检修流程</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 查找故障信息中是否有Warm Up Error（HPF/SD）和X-ray Zero Detect Error等错误，若有，记录相应的HPF值超出标准的通道号；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 作线性测试和mA线性测试，看两组数据中是否有异常数据，若有，分析是否连续14个（Zj/Qj系统）或22个通道（SRi系统）均是不正常数据，则是CAM板问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 检查X线过滤器，若无问题则作准直间隙测试，若有不正常数据，则可能准直器间隙中有灰尘或异物；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．3 中心点伪影</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．3．1 图像表现：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><img data-s="300,640" src="http://mmbiz.qpic.cn/mmbiz/A1DicCH9Vl6NyPYRdpyamWZASxaxvdqhrc1Jw3VnvGwh1RfE83eoFL4GQ0UBicDwFwSSjvPicV1exRn9gTvX3mbrQ/0" data-ratio="0.9315068493150684" data-w="73" /></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．3．2 伪影原因按相关程度排序</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① X线过滤器问题，特别是中间部位有裂纹</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 探测器问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ CAM板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ④ 校准文件问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑤ ADC板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑥ X线球管问题。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．3．3 检修流程：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 查找故障信息中是否有Warm Up Error（HPF/SD）和X-ray Zero Detect Error等错误，若有，记录相应的HPF值超出标准的通道号；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 作线性测试和mA线性测试，看两组数据中是否有异常数据，若有，分析是否连续14个（Zj/Qj系统）或22个通道（SRi系统）均是不正常数据，则是CAM板问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 检查X线过滤器，若无问题则作准直间隙测试，若有不正常数据，则可能准直器间隙中有灰尘或异物；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．4 多环伪影</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．4．1 图像表现</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><img data-s="300,640" src="http://mmbiz.qpic.cn/mmbiz/A1DicCH9Vl6NyPYRdpyamWZASxaxvdqhric5leaXicGBAyibk4sfcFicXrpnQxVHyKJicB9aibh6RG2MIicFCah7qnJaDg/0" data-ratio="0.9154929577464789" data-w="71" /></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．4．2 伪影原因按相关程度排序：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① CAM板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 探测器问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 准直器间隙问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ④ 校准文件问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ⑤ X线球管</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．4．3 检修流程：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 查找故障信息中是否有Warm Up Error，若Warm Up Error 是REF错，确认探测器偏置电压是+1000VDC且偏置电压输入端与地绝缘电阻是9．5兆欧；若Warm Up Error 是HPF或SD错，需检查探测器温度；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 作线性测试，看数据中是否有异常数据，若有，分析是否连续14个（Zj/Qj系统）或22个通道（SRi系统）均是不正常数据，则是CAM板问题；若具有42个通道的周期性，怀疑ADC板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 对比轴位旋转和静态扫描，RAW/MEAN，若静态扫描无旋转扫描的异常数据，则怀疑旋转机架的振动造成伪影；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ④ 作准直器间隙测试，若有不正常数据，则可能准直器间隙中有灰尘或异物；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．5 多环带伪影</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．5．1 图像表现：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><img data-s="300,640" src="http://mmbiz.qpic.cn/mmbiz/A1DicCH9Vl6NyPYRdpyamWZASxaxvdqhrrUdjqDH0JfSaMp9eQcg7Hg4iaibcBlPicxxBZ5n3FtDvXH28U1aCCAHOA/0" data-ratio="0.9259259259259259" data-w="216" /></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．5．2 伪影原因按相关程度排序：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 对Zj/Qj系统：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ADC板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> CAM板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> CAM CONT板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> 准直器间隙问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> 探测器故障。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ②对Legato/SRi系统：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> CAM板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> CAM CONT板故障；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> 准直器间隙问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> 探测器故障。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;">2．5．3 检修流程：</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ① 查找故障信息中是否有Warm Up Error（HPF/SD）和X-ray Zero Detect Error等错误，若有，记录相应的HPF值超出标准的通道号；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ② 作线性测试和mA线性测试，看两组数据中是否有异常数据，若有，分析是否连续14个（Zj/Qj系统）或22个通道（SRi系统）均是不正常数据，则是CAM板问题；</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p class="p0" style="text-indent:22.5000pt; margin-bottom:0pt; margin-top:0pt; text-autospace:ideograph-other; line-height:15.0000pt; "><span style="font-size: 12pt; font-family: 宋体;"> ③ 检查X线过滤器，若无问题则作准直间隙测试，若有不正常数据，则可能准直器间隙中有灰尘或异物。</span><span style="font-size: 12pt; font-family: 宋体;"><o:p></o:p></span></p><p><img data-s="300,640" src="http://mmbiz.qpic.cn/mmbiz/A1DicCH9Vl6NyPYRdpyamWZASxaxvdqhric9AsqWduK1eYu3lA1oulVjUQIWpqOY3DGbaeMJPthuJFnfhRStPO5A/0" data-ratio="0.5573122529644269" data-w="" /></p><p style=";text-align:justify"><span style="color: rgb(0, 176, 80);font-weight: bold;font-size: 16px;font-family: 宋体"><br /></span></p><p style=";text-align:justify"><span style="color: rgb(0, 176, 80);font-weight: bold;font-size: 16px;font-family: 宋体">主页回复“</span><span style="color: rgb(0, 0, 255);font-weight: bold;font-size: 16px;font-family: 宋体">M</span><span style="color: rgb(0, 176, 80);font-weight: bold;font-size: 16px;font-family: 宋体">”查看热点文章</span></p><p><span style="color: rgb(62, 62, 62);font-size: 16px;font-family: 宋体;background-color: rgb(255, 255, 255)">群主微信号：shanying916 </span></p><p><span style="color: rgb(62, 62, 62);font-size: 16px;font-family: 宋体;background-color: rgb(255, 255, 255)">官方QQ群：</span><span style="color: rgb(255, 0, 0);font-weight: bold;font-size: 16px;font-family: 宋体">23823546</span><span style=""> </span><span style="color: rgb(0, 176, 80);font-weight: bold;font-size: 16px;font-family: 宋体">只加工程师</span><span style="color: rgb(62, 62, 62);font-size: 16px;font-family: 宋体;background-color: rgb(255, 255, 255)">，申请入群说明是工程师</span><span style="color: rgb(62, 62, 62);font-size: 16px;font-family: 宋体;background-color: rgb(255, 255, 255)">,公司名称,维修机型</span></p><p><br /></p>
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发表于 2020-10-21 14:01:54