我们衷心感谢圣母院综合成像设备（NDIIF）和Carestream Health公司的这个项目的金融支持。

1。动物<ol><li>对于结果报告如下，C57BL/6J小鼠及四B6.V， 瘦素 OB / J小鼠获得了从杰克逊实验室（巴尔港，主，美国）。的B6.V - 瘦素OB / J小鼠代表肥胖最早的车型之一，并继续积极研究。 B6.V 瘦素OB / J小鼠表现出通过增加脂肪细胞的大小和数量特征的表型和可重达比野生型小鼠多三倍。7,8在这里，B6.V 瘦素OB / J小鼠作为一个积极的就业控制肥胖型说明的Albira CT的CT为基础的脂肪含量测量系统的可行性。 </li><li>成像进行的动物时达到约12个星期。 （4周龄后在B6.V， 瘦素OB / J小鼠的肥胖是清单）。 </li><li>小鼠麻醉由Isofluorane（2.5％的流量），并保持在2.5％下，通过鼻锥成像设置。一个imals被定位俯卧在标准的大鼠与形象的Albira站提供的床（M2M Imaging公司俄亥俄州克利夫兰）。四肢的位置，从一个统一的CT收购的躯干外侧。 </li><li>图像采集完成后，小鼠，从鼻锥和返回直到门诊恢复笼。 </li></ol> 2。图像采集和重建<ol><li>图像采集使用的Albira的CT系统（锐珂分子成像，伍德布里奇，CT）。小鼠麻醉由Isofluorane（2.5％的流量），并保持在2.5％下，通过鼻锥成像设置。收购进行扫描床长度为115毫米，使用600预测。 X射线源被设置为200μA和45 kVp的电压的电流，并加固梁用0.5毫米铝过滤。 </li><li>深近似的CT设置辐射剂量当量为220毫希，浅层剂量当量为357.4毫希沃特。这些剂量超过20倍LD50值比报告。 </li><li>图像重建FBP的算法（滤波反投影）通过Albira套房5.0 Reconstructor使用，使用"标准"参数。这些合并收购和重建设置125微米的各向同性体素产生最后的形象，被视为足以为整个动物分析。有关详细地区具体分析，有35微米的各向同性体素重建可以选择为90微米的最终解决。 </li></ol> 3。图像分析使用PMOD（PMOD科技有限公司，瑞士苏黎世）分析软件进行图像分析。图像PMOD分段，根据总体积密度第一的组织和脂肪体积。 可减少3.1图像进行分析，以减少计算需求。 <ol><li>减少，导航到"主视图 "选项卡。 </李&gt; <li>选择"工具"&gt;"减少"。 </li><li>选择由2 x，y 2，和 Z 2。 </li><li>检查更换 。 </li><li>选择运行 。 </li></ol>消息:" 边框将改变 "显示，一旦减少是完整的。 3.2图像可以被屏蔽，随后利益体积（VOI）分析，以消除床和鼻锥的元素。 <ol><li>为了掩盖，导航飞机，布局，旋转，镜像，三维标志物 &gt; 飞机和布局 。 </li><li>选择显示平面Z。 </li><li>在Z平面上，滚动到鼻锥。 </li><li>选择的主要Visa奥运畅想 "选项卡&gt; 绘制顶点 。 </li><li>周围画动物的感兴趣区域（ROI），鼻子不包括床和鼻锥。 </li><li>选择将实际的投资回报率 。 </li><li>移动到下一个切片， 粘贴缓冲区，通过鼻子的有关飞机的投资回报率 。 </li><li>使用" 编辑组顶点调整是必要的投资回报。 </li><li>选择" 删除"在鼻锥之外的第一架飞机的投资回报率 。 </li><li>产生一个新的VOI的鼻锥之外的第一架飞机，包括在动物周长（不包括动物床）。 </li><li>导航VOI的"工具"&gt;"遮蔽与代数 。 </li><li>提供的对话方块中，输入-1000。 </li><li> 外选定VOIS按钮选择的面膜像素 。 </li></ol>消息:" 操作不可逆的数据，你要继续吗？"显示器。 <ol start="14"><li> 选择 Yes。 </li><li>导航平面布局，旋转，镜像，三维标记 &gt; 飞机及莱超时。 </li><li>选择" 显示所有飞机 。 </li><li>检查VOI的完整性。 </li><li>选择" 保存"。 </li><li>保存分析 。 </li><li>更改文件名的前缀。 </li></ol> 3.3首先，部分动物总体积的形象: <ol><li>选择" 工具"&gt;"外部"。 </li><li>选择分割复选框。 </li><li>输入范围为-300到+3500（来自腹部脂肪区域的密度范围内的密度范围参考）。 </li><li>选择" 运行"分割"。 </li><li>检查分割完整性。 </li><li>选择" 确定"。 </li><li>选择删除的投资回报率 。 </li><li>选择VOI统计 。 </li></ol>报告统计总量。 <ol start="9"><li>记录报道体积。 </l我&gt; </ol> 3.4下，部分脂肪体积的形象: <ol><li>返回到非脂肪量分割分段蒙面形象。 </li><li>要加载蒙面数据保存的文件，检查在 Load窗口的分析框）。 </li><li>选择" 工具"&gt;"外部"。 </li><li>选择分割复选框。 </li><li>输入范围为-200至-50。 </li><li>选择" 运行"分割"。 </li><li>检查分割完整性。 </li><li>选择" 确定"。 </li><li>选择VOI统计 。 </li></ol>报告的统计数据表示的脂肪量。 <ol start="10"><li>记录报道体积。 </li><li>选择" 保存"。 </li><li>保存分析 。 </li><li>更改文件名的前缀。 </li></ol><s阮富仲&gt; 可选:如果皮肤/周边密度仍然存在，"腐蚀和膨胀"协议可能进行VOI的分析，以消除这些地区。 <ol><li> 选择" 工具"&gt;"外部"。 </li><li> 选择形态复选框。 形态视图显示。 </li><li> 选择侵蚀 。 </li><li> 选择" 确定"。 </li><li> 选择" 工具"&gt;"外部"。 </li><li> 选择形态复选框。 形态视图显示。 </li><li> 选择扩张 。 </li><li> 选择" 确定"。 </li></ol> 4。 CT图像的可视化 4.1 VolView V3.2（Kitware，克利夫顿公园，纽约，美国）利用创建渲染三维图像分割的视觉显示。 <ol><l我打开的CT 分析格式的数据集。 </li><li>在弹出窗口中使用的默认设置。 </li><li>打开插件菜单。 </li><li>在实用程序 ，选择" 合并卷 。 </li><li>取消选择重缩放组件 。 </li><li>单击" 分配第二次输入 。 </li><li>选择第二个输入的脂肪分割数据。 </li><li>在弹出窗口中使用的默认设置。 </li><li>单击" 应用插件 。 </li><li> 体积较大的主题鼠标双击视图窗口 。 </li></ol> 4.2返回颜色/透明度"选项卡 。组件的下拉框是指数据集目前正在编辑。两个滑块位于底部的标签，并确定覆盖范围内设定每个组件数据的相对亮度，用0到1的值。对于组件1，THé的CT，我们更倾向于使用灰度颜色方案。要改变颜色: <ol><li> 在标量颜色映射"部分中，双击颜色滑块之一。 </li><li>要删除一个滑块，拖动它开箱。 </li><li>添加一个新的滑块，滑块范围内的任意位置单击。 </li><li>删除滑动条之一。 </li><li>使左边的颜色滑块黑 （标值（S）= -19000）。 </li><li>做出正确的颜色滑块白（（）= 15000）。 </li><li>从标量透明度映射中，通过点击方框内的创建一个新的起点。这将给窗口中的三个点。 </li><li>为中间点，改变的（S）〜-3000，不透明度（O）的值设置为0。 </li><li>在右边的窗口中选择第三点。 </li><li>改变（S）到32000左右， <stronG&gt;Ø为.25。 </li><li>第一点，可以在任何地方在左边，只要Opacity值设置为0。 </li><li>更改组成部分，它应该编辑脂肪的外观。 </li><li>改变颜色滑块通过双击和色相（高）滑动滑块到左边的假色图脂肪红色到红色 。很没有别的应需要调整脂肪的外观。 </li></ol> 4.3要创建一个三板的旋转电影显示的CT，脂肪和覆盖: <ol><li>单击并拖动到直立位置与背对着你的主题鼠标。 </li><li>在组件的重量 ，设置组件的价值2 0只显示CT扫描。 </li><li>单击" 修改"&gt;"相机 。 </li><li>选择帧FO数r的旋转电影（本案中，我们选择了"36"）。 </li><li>改变X旋转360度的价值 。 </li><li>选择创建 。 </li><li>在弹出的对话框中，创建一个新文件夹命名的CT，并保存在TIFF格式的文件，将输出一系列的旋转图像。 </li><li>重复这一步脂肪形象，以及覆盖的脂肪/ CT图像，他们每次保存到单独的文件夹。 </li></ol> 4.4 ImageJ的至五1.43u被用来生成一个旋转的电影文件使用VolView输出图像。 <ol><li> ImageJ的，选择文件&gt;导入&gt;图像序列 。 </li><li>选择CT的文件夹中的第一张图片。该软件会自动检测到的其他文件，并打开它们作为一个堆栈。 </li><li>重复打开的脂肪和覆盖序列。 </li><li>根据分析打开&gt;工具&gt;投资回报率的投资回报经理经理。 </li><li>围绕主题鼠标绘制的投资回报率，排除不必要的背景像素。 </li><li>在ROI经理 ，单击" 添加 "，以增加投资回报率。 </li><li>选择一个不同的图像序列。 </li><li>在ROI经理 ，单击将它应用到图片的投资回报率 。在这种方式中，每个裁剪栈完美匹配。 </li><li>当投资回报率是所有的堆栈，右键单击内的投资回报率。 </li><li>选择" 复制"。 </li><li>选择" 检查重复堆栈框图像的其余部分分开的投资回报率。 </li><li>关闭更大的图像堆栈。 </li><li>重复此过程为所有三个图像序列。 </li><li>去图像&gt;书库&gt;工具&gt;合并栈结合在一起。 </li><li>选择CT栈1。 </li><li>选择栈2发 。 </li><li<html> &gt;重复，并选择1堆栈和堆栈2的叠加结合栈 。 </li><li>现在有三个面板，图像旋转堆栈，可以选择在图像窗口左下角的" 播放预览。 </li><li>保存为一个AVI的电影，选择文件&gt;另存为...&gt;的AVI ... </li><li>点击" 保存 "。 </li></ol> 5。代表结果 WT（只C57BL/6J）小鼠和四个肥胖（B6.V， 瘦素OB / J的）小鼠的结果报告作为用人Albira CT系统的脂肪/总体积比测量有代表性的例子。下面的图1提供了一个代表显示VolView V3.2创建肥胖小鼠CT图像的分割（ 即总量和脂肪量）。 0/3680fig1.jpg"/&gt; 图1。代表的CT图像分割为脂肪。（一）肥胖小鼠（B6.V 瘦素OB / J的）CT灰度总量，（B）在红色的脂肪量，和（C）图像融合。 （四）野生型小鼠（C57BL/6J小鼠）CT在灰度总量，（五）脂肪量在红色，（F）的图像融合。 在下面的表1报告总量，脂肪量，脂肪/总额比率计算，每个WT鼠标和每个肥胖小鼠。 WT组和肥胖组的平均脂肪/总体积比分别为0.09和0.42（ 图2）。肥胖小鼠与野生型小鼠的脂肪/总体积比被发现显着差异（P = 0.001）。 <table border="1"><tbody><tr><td> WT（只C57BL/6J） </td><td> 总计（3厘米） </td><td> 脂肪（3厘米） </td><td> 脂肪/总比率 </td><td> 肥胖（B6.V瘦素OB </SUP&gt; /） </td><td> 总计（3厘米） </td><td> 脂肪（3厘米） </td><td> 脂肪/总比率 </td></tr><tr><td> 动物1 </td><td> 28.79 </td><td> 3.00 </td><td> 0.10 </td><td> 动物1 </td><td> 66.25 </td><td> 26.75 </td><td> 0.40 </td></tr><tr><td> 动物2 </td><td> 33.25 </td><td> 3.05 </td><td> 0.09 </td><td> 动物2 </td><td> 61.15 </td><td> 26.31 </td><td> 0.43 </td></tr><tr><td> 动物3 </td><td> 30.30 </td><td> 2.63 </td><td> 0.09 </td><td> 动物3 </td><td> 64.19 </td><td> 25.7 </td><td> 0.40 </td></tr><tr><td></td><td></td><td></td><td></td><td> 动物4 </td><td> 54.25 </td><td> 23.78 </td><td> 0.44 </td></tr></tbody></table> 表1。总成交量，脂肪量，WT和肥胖小鼠的脂肪/总体积的比率。共有和脂肪量，推导出从使用PMOD VOI的分析图像分割。 <img alt="图2" src="/files/ftp_upload/3680/3680fig2.jpg" /> 图2。平均肥胖小鼠与野生型小鼠的脂肪/总体积的比率。平均为WT（只C57BL/6J）与肥胖（B6.V， 瘦素OB / J的）脂肪/总体积的比率是0.09和0.42分别显示。 （误差线=单一的标准偏差）。野生与肥胖的脂肪/总体积比被发现显着差异（p值= 0.001）。

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托德·A·震荡波，Shengting李肖恩体育顿，和Seth T.的金门是锐珂分子成像的员工。卡洛斯Correcher是一个Oncovision雇员，宝石影像看到马修Leevy是锐珂分子成像的顾问。

在这里，利用B6.V 瘦素OB / J小鼠，我们已经说明了在一个小的动物使用的Albira的CT系统模型进行脂肪含量测量的可行性。这些测量与比较组内和组间测量的期望是一致的。首先，这里提供有代表性的成果，突出有限集团内部WT和肥胖小鼠使用这些程序组中的脂肪/总体积比测量的变化。其次，野生型与肥胖小鼠的脂肪/总量比差异显着。最后，根据以前的值相对总脂肪量和野生与B6.V 瘦素OB / J小鼠体脂肪百分比比较（未显示），野生与脂肪/总体积比我们的测量B6.V LEP OB / J小鼠属于预期范围内，7，8。 这里详细的方法可以适用或适用于其他Models和/或研究的目标。重建参数的修改，可能需要达到的具体目标。例如，Judex 等 。 （2010）报道，一些地区的具体分析需要50微米的高分辨率图像。一厘米图像的各向同性卷可以选择的Albira 5.0套房Reconstructor使用"人力资源"重建选项为35微米的重建。一旦已被利用的具体地区和器官的脂肪含量测量的Albira CT系统的全部好处的CT为基础的脂肪含量分析（即同时区域和特定器官的脂肪量的测量和纵向测量），可实现的Albira CT系统。 结论: 在这里，我们提供了一个详细的，一步一步使用X射线CT成像生活小鼠中脂肪含量的测量方法。我们收购的CT数据集使用一个Albira形象站，并进行后续的分割和全日空裂解使用PMOD软件的套件。最后，我们提供的指示，使浅显的渲染和可视化在整个动物的脂肪组织分布。

segmentation and measurement of fat volumes in murine obesity models using x-ray computed tomography

肥胖增加发病率和死亡率以及降低生活质量的指标与1这两种遗传和环境因素与肥胖有关，虽然精确，有助于疾病的基本机制，目前正在划定。2,3几个小动物肥胖模型已开发和在研究各种就业。这些实验的一个关键组成部分，涉及的各种条件下的区域和/或总的动物脂肪含量数据的收集。 传统的实验方法可用于测量肥胖的小动物模型中的脂肪含量，包括侵入性（如脂肪沉积的体外测量）和非侵入性的协议（如双能X射线骨密度仪（DEXA），或磁共振（MR）），每个呈现相对权衡。当前侵入性方法测量脂肪含量可能会提供详细情况机关和地区特定的脂肪分布，但牺牲的对象将排除纵向评估。相反，当前的非侵入性的战略提供器官和地区特定的脂肪分布的细节有限，但使宝贵的纵向评估。用专用的小动物，X射线计算机断层扫描（CT）系统和定制的分析程序，无论是机关和脂肪的分布区域和纵向分析具体分析的出现是可能的。最近的报告已经证实在活小鼠体内肥胖的纵向成像的CT使用。5,6在这里，我们提供了一个修改后的方法，允许/总脂肪量测量，分析和利用结合锐珂分子成像Albira CT系统可视化与PMOD与Volview套装软件。

Watch this Scientific Journal Video about Segmentation and Measurement of Fat Volumes in Murine Obesity Models Using X-ray Computed Tomography at JoVE.com

Segmentation and Measurement of Fat Volumes in Murine Obesity Models Using X-ray Computed Tomography

脂肪含量的分析，定期进行在利用小鼠肥胖模型的研究。新兴的小动物CT成像和分析的方法为纵向细节丰富的脂肪含量分析。在这里，我们表演小动物CT成像，分析和可视化的步骤的详细步骤。

利用X射线计算机断层扫描在小鼠肥胖模型的FAT卷的分割和测量

Obesity is associated with increased morbidity and mortality as well as reduced metrics in quality of life.1 Both environmental and genetic factors are ...

segmentation-measurement-fat-volumes-murine-obesity-models-using-x

Nanyang Technological University

Research

JoVE Journal

Medicine

16.0K 次观看.  Carestream Molecular Imaging. 脂肪含量的分析，定期进行在利用小鼠肥胖模型的研究。新兴的小动物CT成像和分析的方法为纵向细节丰富的脂肪含量分析。在这里，我们表演小动物CT成像，分析和可视化的步骤的详细步骤。

视频: Segmentation and Measurement of Fat Volumes in Murine Obesity Models Using X-ray Computed Tomography

X-ray Dose Reduction through Adaptive Exposure in Fluoroscopic Imaging

X-ray fluoroscopy is widely used for image guidance during cardiac intervention. However, radiation dose in these procedures can be high, and this is a significant concern, particularly in pediatric applications. Pediatrics procedures are in general much more complex than those performed on adults and thus are on average four to eight times longer1. Furthermore, children can undergo up to 10 fluoroscopic procedures by the age of 10, and have been shown to have a three-fold higher risk of developing fatal cancer throughout their life than the general population2,3.
We have shown that radiation dose can be significantly reduced in adult cardiac procedures by using our scanning beam digital x-ray (SBDX) system4-- a fluoroscopic imaging system that employs an inverse imaging geometry5,6 (Figure 1, Movie 1 and Figure 2). Instead of a single focal spot and an extended detector as used in conventional systems, our approach utilizes an extended X-ray source with multiple focal spots focused on a small detector. Our X-ray source consists of a scanning electron beam sequentially illuminating up to 9,000 focal spot positions. Each focal spot projects a small portion of the imaging volume onto the detector. In contrast to a conventional system where the final image is directly projected onto the detector, the SBDX uses a dedicated algorithm to reconstruct the final image from the 9,000 detector images.
For pediatric applications, dose savings with the SBDX system are expected to be smaller than in adult procedures. However, the SBDX system allows for additional dose savings by implementing an electronic adaptive exposure technique. Key to this method is the multi-beam scanning technique of the SBDX system: rather than exposing every part of the image with the same radiation dose, we can dynamically vary the exposure depending on the opacity of the region exposed. Therefore, we can significantly reduce exposure in radiolucent areas and maintain exposure in more opaque regions. In our current implementation, the adaptive exposure requires user interaction (Figure 3). However, in the future, the adaptive exposure will be real time and fully automatic.
We have performed experiments with an anthropomorphic phantom and compared measured radiation dose with and without adaptive exposure using a dose area product (DAP) meter. In the experiment presented here, we find a dose reduction of 30%.

We are developing a dynamic adaptive exposure technique using our scanning beam digital X-ray system. Rather than exposing an object uniformly, the exposure is adapted depending on the opacity of the object. Here we show an experiment on an anthropomorphic phantom that resulted in a dose saving of 30%.

通过自适应曝光的减少剂量X射线透视影像

X-ray fluoroscopy is widely used for image guidance during cardiac intervention. However, radiation dose in these procedures can be high, and this is a ...

科研

医学

Quantification of Atherosclerotic Plaque Activity and Vascular Inflammation using [18-F] Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (FDG-PET/CT)

Conventional non-invasive imaging modalities of atherosclerosis such as coronary artery calcium (CAC)1 and carotid intimal medial thickness (C-IMT)2 provide information about the burden of disease. However, despite multiple validation studies of CAC3-5, and C-IMT2,6, these modalities do not accurately assess plaque characteristics7,8, and the composition and inflammatory state of the plaque determine its stability and, therefore, the risk of clinical events9-13.
[18F]-2-fluoro-2-deoxy-D-glucose (FDG) imaging using positron-emission tomography (PET)/computed tomography (CT) has been extensively studied in oncologic metabolism14,15. Studies using animal models and immunohistochemistry in humans show that FDG-PET/CT is exquisitely sensitive for detecting macrophage activity16, an important source of cellular inflammation in vessel walls. More recently, we17,18 and others have shown that FDG-PET/CT enables highly precise, novel measurements of inflammatory activity of activity of atherosclerotic plaques in large and medium-sized arteries9,16,19,20. FDG-PET/CT studies have many advantages over other imaging modalities: 1) high contrast resolution; 2) quantification of plaque volume and metabolic activity allowing for multi-modal atherosclerotic plaque quantification; 3) dynamic, real-time, in vivo imaging; 4) minimal operator dependence. Finally, vascular inflammation detected by FDG-PET/CT has been shown to predict cardiovascular (CV) events independent of traditional risk factors21,22 and is also highly associated with overall burden of atherosclerosis23. Plaque activity by FDG-PET/CT is modulated by known beneficial CV interventions such as short term (12 week) statin therapy24 as well as longer term therapeutic lifestyle changes (16 months)25.
The current methodology for quantification of FDG uptake in atherosclerotic plaque involves measurement of the standardized uptake value (SUV) of an artery of interest and of the venous blood pool in order to calculate a target to background ratio (TBR), which is calculated by dividing the arterial SUV by the venous blood pool SUV. This method has shown to represent a stable, reproducible phenotype over time, has a high sensitivity for detection of vascular inflammation, and also has high inter-and intra-reader reliability26. Here we present our methodology for patient preparation, image acquisition, and quantification of atherosclerotic plaque activity and vascular inflammation using SUV, TBR, and a global parameter called the metabolic volumetric product (MVP). These approaches may be applied to assess vascular inflammation in various study samples of interest in a consistent fashion as we have shown in several prior publications.9,20,27,28

Quantification of Atherosclerotic Plaque Activity and Vascular Inflammation using [18-F] Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography FDG-PET/CT

There is great need to identify atherosclerosis non-invasively, and here we demonstrate how FDG-PET/CT can be used to detect and quantify atherosclerotic plaque activity and vascular inflammation.

动脉粥样硬化斑块的活动和血管炎症的定量使用[18 F]，氟正电子发射断层扫描/电脑断层扫描（FDG-PET/CT）

Conventional non-invasive imaging modalities of atherosclerosis such as coronary artery calcium (CAC)1 and carotid intimal medial thickness (C-IMT)2 ...

Computed Tomography-guided Time-domain Diffuse Fluorescence Tomography in Small Animals for Localization of Cancer Biomarkers

Small animal fluorescence molecular imaging (FMI) can be a powerful tool for preclinical drug discovery and development studies1. However, light absorption by tissue chromophores (e.g., hemoglobin, water, lipids, melanin) typically limits optical signal propagation through thicknesses larger than a few millimeters2. Compared to other visible wavelengths, tissue absorption for red and near-infrared (near-IR) light absorption dramatically decreases and non-elastic scattering becomes the dominant light-tissue interaction mechanism. The relatively recent development of fluorescent agents that absorb and emit light in the near-IR range (600-1000 nm), has driven the development of imaging systems and light propagation models that can achieve whole body three-dimensional imaging in small animals3.
Despite great strides in this area, the ill-posed nature of diffuse fluorescence tomography remains a significant problem for the stability, contrast recovery and spatial resolution of image reconstruction techniques and the optimal approach to FMI in small animals has yet to be agreed on. The majority of research groups have invested in charge-coupled device (CCD)-based systems that provide abundant tissue-sampling but suboptimal sensitivity4-9, while our group and a few others10-13 have pursued systems based on very high sensitivity detectors, that at this time allow dense tissue sampling to be achieved only at the cost of low imaging throughput. Here we demonstrate the methodology for applying single-photon detection technology in a fluorescence tomography system to localize a cancerous brain lesion in a mouse model.
The fluorescence tomography (FT) system employed single photon counting using photomultiplier tubes (PMT) and information-rich time-domain light detection in a non-contact conformation11. This provides a simultaneous collection of transmitted excitation and emission light, and includes automatic fluorescence excitation exposure control14, laser referencing, and co-registration with a small animal computed tomography (microCT) system15. A nude mouse model was used for imaging. The animal was inoculated orthotopically with a human glioma cell line (U251) in the left cerebral hemisphere and imaged 2 weeks later. The tumor was made to fluoresce by injecting a fluorescent tracer, IRDye 800CW-EGF (LI-COR Biosciences, Lincoln, NE) targeted to epidermal growth factor receptor, a cell membrane protein known to be overexpressed in the U251 tumor line and many other cancers18. A second, untargeted fluorescent tracer, Alexa Fluor 647 (Life Technologies, Grand Island, NY) was also injected to account for non-receptor mediated effects on the uptake of the targeted tracers to provide a means of quantifying tracer binding and receptor availability/density27. A CT-guided, time-domain algorithm was used to reconstruct the location of both fluorescent tracers (i.e., the location of the tumor) in the mouse brain and their ability to localize the tumor was verified by contrast-enhanced magnetic resonance imaging.
Though demonstrated for fluorescence imaging in a glioma mouse model, the methodology presented in this video can be extended to different tumor models in various small animal models potentially up to the size of a rat17.

Diffuse fluorescence tomography offers a relatively low-cost and potentially high-throughout approach to preclinical in vivo tumor imaging. The methodology of optical data collection, calibration, and image reconstruction is presented for a computed tomography-guided non-contact time-domain system using fluorescent targeting of the tumor biomarker epidermal growth factor receptor in a mouse glioma model.

电脑断层导引的时域漫荧光体层摄影术在小动物的肿瘤生物标志物的本土化

Small animal fluorescence molecular imaging (FMI) can be a powerful tool for preclinical drug discovery and development studies1. However, light ...

Multi-modal Imaging of Angiogenesis in a Nude Rat Model of Breast Cancer Bone Metastasis Using Magnetic Resonance Imaging, Volumetric Computed Tomography and Ultrasound

Angiogenesis is an essential feature of cancer growth and metastasis formation. In bone metastasis, angiogenic factors are pivotal for tumor cell proliferation in the bone marrow cavity as well as for interaction of tumor and bone cells resulting in local bone destruction. Our aim was to develop a model of experimental bone metastasis that allows in vivo assessment of angiogenesis in skeletal lesions using non-invasive imaging techniques.
For this purpose, we injected 105 MDA-MB-231 human breast cancer cells into the superficial epigastric artery, which precludes the growth of metastases in body areas other than the respective hind leg1. Following 25-30 days after tumor cell inoculation, site-specific bone metastases develop, restricted to the distal femur, proximal tibia and proximal fibula1. Morphological and functional aspects of angiogenesis can be investigated longitudinally in bone metastases using magnetic resonance imaging (MRI), volumetric computed tomography (VCT) and ultrasound (US).
MRI displays morphologic information on the soft tissue part of bone metastases that is initially confined to the bone marrow cavity and subsequently exceeds cortical bone while progressing. Using dynamic contrast-enhanced MRI (DCE-MRI) functional data including regional blood volume, perfusion and vessel permeability can be obtained and quantified2-4. Bone destruction is captured in high resolution using morphological VCT imaging. Complementary to MRI findings, osteolytic lesions can be located adjacent to sites of intramedullary tumor growth. After contrast agent application, VCT angiography reveals the macrovessel architecture in bone metastases in high resolution, and DCE-VCT enables insight in the microcirculation of these lesions5,6. US is applicable to assess morphological and functional features from skeletal lesions due to local osteolysis of cortical bone. Using B-mode and Doppler techniques, structure and perfusion of the soft tissue metastases can be evaluated, respectively. DCE-US allows for real-time imaging of vascularization in bone metastases after injection of microbubbles7.
In conclusion, in a model of site-specific breast cancer bone metastases multi-modal imaging techniques including MRI, VCT and US offer complementary information on morphology and functional parameters of angiogenesis in these skeletal lesions.

In the pathogenesis of bone metastasis, angiogenesis is a crucial process and therefore represents a target for imaging and therapy. Here, we present a rat model of site-specific breast cancer bone metastasis and describe strategies to non-invasively image angiogenesis in vivo using magnetic resonance imaging, volumetric computed tomography and ultrasound.

利用磁共振成像，容积电脑断层扫描及超音波的裸鼠乳腺癌骨转移大鼠模型血管生成的多模态成像

Angiogenesis is an essential feature of cancer growth and metastasis formation. In bone metastasis, angiogenic factors are pivotal for tumor cell ...

Dual-phase Cone-beam Computed Tomography to See, Reach, and Treat Hepatocellular Carcinoma during Drug-eluting Beads Transarterial Chemo-embolization

The advent of cone-beam computed tomography (CBCT) in the angiography suite has been revolutionary in interventional radiology. CBCT offers 3 dimensional&#160;(3D) diagnostic imaging in the interventional suite and can enhance minimally-invasive therapy beyond the limitations of 2D angiography alone. The role of CBCT has been recognized in transarterial chemo-embolization (TACE) treatment of hepatocellular carcinoma (HCC). The recent introduction of a CBCT technique: dual-phase CBCT (DP-CBCT) improves intra-arterial HCC treatment with drug-eluting beads (DEB-TACE). DP-CBCT can be used to localize liver tumors with the diagnostic accuracy of multi-phasic multidetector computed tomography (M-MDCT) and contrast enhanced magnetic resonance imaging (CE-MRI) (See the tumor), to guide intra-arterially guidewire and microcatheter to the desired location for selective therapy (Reach the tumor), and to evaluate treatment success during the procedure (Treat the tumor). The purpose of this manuscript is to illustrate how DP-CBCT is used in DEB-TACE to see, reach, and treat HCC.

Dual-phase cone-beam computed tomography (DP-CBCT) is a useful intraprocedural imaging technique for transarterial chemo-embolization treatment with drug-eluting beads of hepatocellular carcinoma. DP-CBCT has been used to perform three major steps in oncologic interventional radiology: tumor localization (see), navigation and intraprocedural catheter guidance (reach), and intraprocedural evaluation of treatment success (treat).

双相位锥束CT看看，到达，并在药物洗脱珠Transarterial化疗栓塞治疗原发性肝癌

The advent of cone-beam computed tomography (CBCT) in the angiography suite has been revolutionary in interventional radiology. CBCT offers 3 ...

Assessment of Viability of Human Fat Injection into Nude Mice with Micro-Computed Tomography

Lipotransfer is a vital tool in the surgeon&#8217;s armamentarium for the treatment of soft tissue deficits of throughout the body. Fat is the ideal soft tissue filler as it is readily available, easily obtained, inexpensive, and inherently biocompatible.1 However, despite its burgeoning popularity, fat grafting is hampered by unpredictable results and variable graft survival, with published retention rates ranging anywhere from 10-80%. 1-3
To facilitate investigations on fat grafting, we have therefore developed an animal model that allows for real-time analysis of injected fat volume retention. Briefly, a small cut is made in the scalp of a CD-1 nude mouse and 200-400 &#181;l&#160;of processed lipoaspirate is placed over the skull. The scalp is chosen as the recipient site because of its absence of native subcutaneous fat, and because of the excellent background contrast provided by the calvarium, which aids in the analysis process. Micro-computed tomography (micro-CT) is used to scan the graft at baseline and every two weeks thereafter. The CT images are reconstructed, and an imaging software is used to quantify graft volumes.
Traditionally, techniques to assess fat graft volume have necessitated euthanizing the study animal to provide just a single assessment of graft weight and volume by physical measurement ex vivo. Biochemical and histological comparisons have likewise required the study animal to be euthanized. This described imaging technique offers the advantage of visualizing and objectively quantifying volume at multiple time points after initial grafting without having to sacrifice the study animal. The technique is limited by the size of the graft able to be injected as larger grafts risk skin and fat necrosis. This method has utility for all studies evaluating fat graft viability and volume retention. It is particularly well-suited to providing a visual representation of fat grafts and following changes in volume over time.

Fat grafting is an essential technique for reconstructing soft tissue deficits. However, it remains an unpredictable procedure characterized by variable graft survival. Our goal was to devise a mouse model that utilizes a novel imaging method to compare volume retention between differing techniques of fat graft preparation and delivery.

评估人体脂肪注射生存能力的裸鼠与微型计算机断层扫描

Lipotransfer is a vital tool in the surgeon&#8217;s armamentarium for the treatment of soft tissue deficits of throughout the body. Fat is the ideal soft ...

Real-time X-ray Imaging of Lung Fluid Volumes in Neonatal Mouse Lung

At birth, the lung undergoes a profound phenotypic switch from secretion to absorption, which allows for adaptation to breathing independently. Promoting and sustaining this phenotype is critically important in normal alveolar growth and gas exchange throughout life. Several in vitro studies have characterized the role of key regulatory proteins, signaling molecules, and steroid hormones that can influence the rate of lung fluid clearance. However, in vivo examinations must be performed to evaluate whether these regulatory factors play important physiological roles in regulating perinatal lung liquid absorption. As such, the utilization of real time X-ray imaging to determine perinatal lung fluid clearance, or pulmonary edema, represents a technological advancement in the field. Herein, we explain and illustrate an approach to assess the rate of alveolar lung fluid clearance and alveolar flooding in C57BL/6 mice at post natal day 10 using X-ray imaging and analysis. Successful implementation of this protocol requires prior approval from institutional animal care and use committees (IACUC), an in vivo small animal X-ray imaging system, and compatible molecular imaging software.

We present a protocol to assess the rate of alveolar fluid clearance or pulmonary edema in neonatal mouse lung using X-ray imaging technology.

在新生小鼠肺肺流体体积的实时X射线成像

At birth, the lung undergoes a profound phenotypic switch from secretion to absorption, which allows for adaptation to breathing independently. Promoting ...

Continuous Blood Sampling in Small Animal Positron Emission Tomography/Computed Tomography Enables the Measurement of the Arterial Input Function

For quantitative analysis and bio-kinetic modeling of positron emission tomography/computed tomography (PET/CT) data, the determination of the temporal blood time-activity concentration also known as arterial input function (AIF) is a key point, especially for the characterization of animal disease models and the introduction of newly developed radiotracers. The knowledge of radiotracer availability in the blood helps to interpret PET/CT-derived data of tissue activity. For this purpose, online blood sampling during the PET/CT imaging is advisable to measure the AIF. In contrast to manual blood sampling and image-derived approaches, continuous online blood sampling has several advantages. Besides the minimized blood loss, there is an improved resolution and a superior accuracy for the blood activity measurement. However, the major drawback of online blood sampling is the costly and time-consuming preparation to catheterize the femoral vessels of the animal. Here, we describe an easy and complete workflow for catheterization and continuous blood sampling during small animal PET/CT imaging and compared it to manual blood sampling and an image-derived approach. Using this highly-standardized workflow, the determination of the fluorodeoxyglucose ([18F]FDG) AIF is demonstrated. Further, this procedure can be applied to any radiotracer in combination with different animal models to create fundamental knowledge of tracer kinetic and model characteristics. This allows a more precise evaluation of the behavior of pharmaceuticals, both for diagnostic and therapeutic approaches in the preclinical research of oncological, neurodegenerative and myocardial diseases.

Here a protocol for continuous blood sampling during PET/CT imaging of rats to measure the arterial input function (AIF) is described. The catheterization, the calibration and setup of the system and the data analysis of the blood radioactivity are demonstrated. The generated data provide input parameters for subsequent bio-kinetic modeling.

小型动物正电子发射断层扫描/计算机断层扫描中的连续血液采样支持动脉输入函数的测量

For quantitative analysis and bio-kinetic modeling of positron emission tomography/computed tomography (PET/CT) data, the determination of the temporal ...

Vinyl Chloride and High-Fat Diet as a Model of Environment and Obesity Interaction

Vinyl chloride (VC), an abundant environmental contaminant, causes steatohepatitis at high levels, but is considered safe at lower levels. Although several studies have investigated the role of VC as a direct hepatotoxicant, the concept that VC modifies sensitivity of the liver to other factors, such as nonalcoholic fatty liver disease (NAFLD) caused by high-fat diet (HFD) is novel. This protocol describes an exposure paradigm to evaluate the effects of chronic, low-level exposure to VC. Mice are acclimated to low-fat or high-fat diet one week prior to the beginning of the inhalation exposure and remain on these diets throughout the experiment. Mice are exposed to VC (sub-OSHA level: &#60;1 ppm) or room air in inhalation chambers for 6 hours/day, 5 days/week, for up to 12 weeks. Animals are monitored weekly for body weight gain and food consumption. This model of VC exposure causes no overt liver injury with VC inhalation alone. However, the combination of VC and HFD significantly enhances liver disease. A technical advantage of this co-exposure model is the whole-body exposure, without restraint. Moreover, the conditions more closely resemble a very common human situation of a combined exposure to VC with underlying nonalcoholic fatty liver disease and therefore support the novel hypothesis that VC is an environmental risk factor for the development of liver damage as a complication of obesity (i.e., NAFLD). This work challenges the paradigm that the current exposure limits of VC (occupational and environmental) are safe. The use of this model can shed new light and concern on the risks of VC exposure. This model of toxicant-induced liver injury can be used for other volatile organic compounds and to study other interactions that may impact the liver and other organ systems.

The goal of this protocol was to develop a murine model of low-level toxicant exposure that does not cause overt liver injury but rather exacerbates pre-existing liver damage. This paradigm better recapitulates human exposure and the subtle changes that occur upon exposure to toxicant concentrations that are considered safe.

氯乙烯和高脂肪饮食作为环境与肥胖相互作用的典范

Vinyl chloride (VC), an abundant environmental contaminant, causes steatohepatitis at high levels, but is considered safe at lower levels. Although ...

Segmentation and Linear Measurement for Body Composition Analysis using Slice-O-Matic and Horos

Body composition is associated with risk of disease progression and treatment complications in a variety of conditions. Therefore, quantification of skeletal muscle mass and adipose tissues on Computed Tomography (CT) and/or Magnetic Resonance Imaging (MRI) may inform surgery risk evaluation and disease prognosis. This article describes two quantification methods originally described by Mourtzakis et al. and Avrutin et al.: tissue segmentation and linear measurement of skeletal muscle. Patients' cross-sectional image at the midpoint of the third lumbar vertebra was obtained for both measurements. For segmentation, the images were imported into Slice-O-Matic and colored for skeletal muscle, intramuscular adipose tissue, visceral adipose tissue, and subcutaneous adipose tissue. Then, surface areas of each tissue type were calculated using the tag surface area function. For linear measurements, the height and width of bilateral psoas and paraspinal muscles at the level of the third lumbar vertebra are measured and the calculation using these four values yield the estimated skeletal muscle mass. Segmentation analysis provides quantitative, comprehensive information about the patients' body composition, which can then be correlated with disease progression. However, the process is more time-consuming and requires specialized training. Linear measurements are an efficient and clinic-friendly tool for quick preoperative evaluation. However, linear measurements do not provide information on adipose tissue composition. Nonetheless, these methods have wide applications in a variety of diseases to predict surgical outcomes, risk of disease progression and inform treatment options for patients.

Segmentation and linear measurements quantify skeletal muscle mass and adipose tissues using Computed Tomography and/or Magnetic Resonance Imaging images. Here, we outline the use of Slice-O-Matic software and Horos image viewer for rapid and accurate analysis of body composition. These methods can provide important information for prognosis and risk stratification.

使用切片-O-马蒂奇和霍罗斯进行身体成分分析的细分和线性测量

Body composition is associated with risk of disease progression and treatment complications in a variety of conditions. Therefore, quantification of ...