Name: human brown adipose tissue depots automatically segmented by positron emission tomography/computed tomography and registered magnetic resonance images
Uploaded: 2015-02-18T13:00:00.000+00:00
Duration: 9 min 21 s
Description: Watch this Scientific Journal Video about Human Brown Adipose Tissue Depots Automatically Segmented by Positron Emission Tomography/Computed Tomography and Registered Magnetic Resonance Images at JoVE

We would like to thank the Vanderbilt University Institute of Imaging Science MRI technologists David Pennell, Leslie McIntosh, and Kristen George-Durrett, and the team of Vanderbilt University Medical Center PET/CT technologists led by Martha D. Shone. This work was supported by the following grants from the NIH: NCATS/NIH UL1 RR024975, NIDDK/NIH R21DK096282, NCI/NIH R25CA136440, and NIBIB/NIH T32EB014841.

注意:这个研究所的当地伦理委员会批准了这项研究，并提供了所有科目笔试之前参与的知情同意书。为了有资格的研究中，受试者必须满足以下要求:没有已知的糖尿病;没有用β受体阻滞剂或焦虑的药物，目前或过去的;不吸烟或咀嚼烟草产品，目前或过去;不超过4个杯每天咖啡因;不超过2个眼镜每天醇;如果女性不怀孕或哺乳。 注:在本研究中，每个参与者经历了四级考试:2 MRI和两个PET-CT。每次考试获取在不同的一天，既有适温24.5±0.7℃（76.2±1.3°F），下进行的各成像模态，和冷17.4±0.5℃（63.4±0.9°F）的条件。的扫描都没有安排在任何特定的顺序，从而有助于最小化任何潜在的偏压由于加热或冷却中的数据在一个特定的顺序的主题。为1的PET-CT扫描的总有效辐射剂量为6.4毫（毫），并在工作人员的放射科医师建议每次扫描之间的至少24小时的清除期。 1.一般MRI安全性和成像关注<ol><li>由于主磁场MRI机器总是在，照顾，以确保患者的安全和MR区域工作的所有人员。清除这一问题的所有磁性物体以及任何在该地区工作的人员。 </li><li>在招聘阶段要求科目，如果他们有他们的尸体43的任何金属。此外，有主题完成安全磁筛选过程44，以保证身体的任何金属被批准用于MRI。这个最初的检查可以帮助消除同意主题谁也不能完成MRI扫描的可能性。 </li><li>此外，如果有在被检者的身体，这与MR兼容的任何金属，确保第在金属不靠近感兴趣的组织。这是因为金属会导致图像失真文物，这将使得分析困难，如果不是不可能的。 </li></ol> 2.获得知情同意<ol><li>满足与受试者获得书面知情同意。在这次会议上，涵盖研究的所有细节，例如:访问次数，每次访问时间的承诺，有什么要求就限制主体行使和/或食品中，个体可以，不能在做什么访问（如睡眠），以及任何其他细节。利用这次会议安排了扫描的访问，因为它通常是比较容易的人，而不是使用多个电子邮件安排这些。 </li></ol> 3.程序之前访问<ol><li>说明主题<ol><li> 24小时到达的研究之前，有酒精，咖啡因，药物或任何剧烈运动或行为的主体副歌ivity。 </li><li>指示受试者对快，并避免任何热量摄入8小时到达该研究之前。受试者被允许喝水。 </li></ol></li><li>联系志愿者<ol><li>当天他们24小时准备开始前提醒的具体指示的志愿者。这既作为扫描的提醒，以及它有助于确保受试者记住他们的限制，（ 即 ，不进食，不运动，无酒精， 等 ）。 </li></ol></li></ol> 4.程序的研究日 - 用于MRI <ol><li>温度控制机房准备<ol><li>用一个小房间内温度受控室，其中所述受试者被暴露于所需的温度。 注意:通过使用一个小房间，也能够最大限度地减少在房间温度梯度。例如，这里使用的房间大小为7&#39;×6&#39;8"×8&#39;高，（373.33立方英尺）。 </li><li>准备之前进入房间，以便有足够的时间为房间达到稳定的温度的主体室至少60分钟。 </li><li>保持对RT要么与便携式空调装置和一个旋转底板风扇以保持冷气循环，或使用可编程便携式加热器，其振荡循环在房间的暖空气。 </li><li>停用或减少任何现有恒温控制空调或房间的加热，以避免相互冲突的与所需的RT终端的便携设备。 </li></ol></li><li>之前进入恒温室<ol><li>有主题的变化转换成标准的医疗短裤和衬衫。删除袜子和鞋子。如果拍摄对象是女性，让运动胸罩不含任何金属的磨损。 </li><li>改变成标准衣物后测量被检者的身高，体重和腰围测量。 </li><li>测量被检者的体温全光照GA舌下温度计。 </li></ol></li><li>在温控室<ol><li>指示受试者进入温度受控室。让拍摄对象静静的坐着，不执行任何可能改变体温， 如活性，运动，打字，或入睡。 </li><li>坐在房间1小时后，用舌下温度计再次测量体温。 </li><li>坐在所述温度受控室的第二小时后，用舌下温度计再次测量体温。 </li><li>关于当受试者坐在在冷室中的MRI天，使用冷背心保持寒冷的环境，而主体被输送到MRI扫描仪。放在前向受试者而使温度受控室的主体的冷背心。 </li><li> 2小时后，在温度受控室，输送在轮椅到MRI扫描仪的主体。使用轮椅，以保持学科在重新laxed，久坐不动的状态，并尽量减少任何"升温"，从走路可能发生的。此外，使用轮椅有助于避免在PET示踪剂的任何摄取到骨骼肌，虽然它可能会是最小的。 </li></ol></li><li> MRI收购协议<ol><li>收购MRI扫描采用3T MRI扫描仪配备了双通道并行传输能力，超大的16通道躯干接收线圈和修改桌面。 </li><li>挂躯干的前部接收线圈从扫描器膛的在织物吊索的顶部。允许吊索挂低到足以滑动针对被检者的身体以便最大化信噪比（SNR）。 </li><li>放置在躯干的后部接收线圈在一个滚动"线圈车皮"桌面的两层之间。作为表移动通过扫描仪内孔，通过安装在扫描器绑带保持线圈车皮在等角点覆盖在前面和叔背面他电脑灯孔，使得后部线圈元件保持静止。 </li><li>定位在床的受试者在仰卧位置的第一输入扫描器脚。 <ol><li>如果拍摄对象是穿着冷背心，删除马甲的主题之前，躺着。 </li></ol></li><li>一旦躺着，已受试者地方两臂内类似于枕套一个袋子，并且降低臂到主体的任一侧。这有助于确保肩部都在MRI和PET / CT检查，这使得图像配准过程中更容易定位在一个类似的方式。 注:允许受躺在扫描台上自然，利用每一个扫描过程中头下缓冲相同数量，并使用枕套袋来支持武器，都有助于减少扫描之间受定位之间的差异。在一个扫描周期用于受试者的任何支持，例如膝盖下一个枕头或下背部，应始终以同样的方式对第使用在主题，期间无论是MRI和PET / CT扫描。 </li><li>获得使用多协议栈，多层，多领域的快速回波（mFFE）收购7成堆的20轴位片，从头顶到大腿上部覆盖脂肪水MRI（FWMRI）。片是连续与片之间的0毫米差距。 <ol><li>收集FWMRI扫描使用定制软件，使收购获得的两个交错套四呼应了TR = 83毫秒，TE 1 = 1.024毫秒，有效ΔTE= 0.779毫秒8相呼应。其它采集协议的细节，包括:翻转角= 20度，水的脂肪移= 0.323像素，读出用采样带宽= 1346.1赫兹/像素，轴向平面内的视场=520毫米×408毫米，获得体素尺寸为2mm×2mm的X7.5毫米和灵敏度编码（SENSE）平行成像因子= 3（前后方向）。每个站准备阶段包括中心频率（F 0）的优化和一阶线性匀场。 Acquisiti时间是27.8秒，20片。 </li><li>执行呼吸保持着站覆盖骨盆肩上有两个呼吸每站的成立， 即 ，无呼吸暂停的时间超过14秒。在每个表中的位置，取得了双角度B 1校准扫描（采集时间15.1秒），以使优化的RF匀场（相对RF振幅和相位调整）为扫描仪的双通道传输能力。 </li><li>在收购与12.1秒的采集时间每个表位置的SENSE参考扫描。推荐FWMRI参数列于表1中 。 </li></ol></li></ol></li></ol> 5.程序上的研究日 - 为PET-CT <ol><li>温度控制机房准备<ol><li>用一个小房间内温度受控室，其中所述受试者被暴露于所需的温度。 注意:通过使用一个小房间，也能够最大限度地减少在房间温度梯度。 ˚F或者例如，这里使用的房间大小为7&#39;×6&#39;8"×8&#39;高，（373.33立方英尺）。 </li><li>房间准备进入房间，以便有足够的时间为房间达到稳定的温度的主体，至少60分钟之前。 </li><li>保持对RT要么与便携式空调装置和一个旋转底板风扇以保持冷气循环以达到冷刺激的温度，或者使用oscaillating便携式加热器以保持热中性温度。 </li><li>停用或减少任何现有恒温控制空调或房间的加热，以避免相互冲突的与所需的RT终端的便携设备。 </li></ol></li><li>受准备<ol><li>直接受PET成像套件有放置在手或手臂静脉静脉口。此四端口允许放射科技术人员到放射性示踪剂后注入，当对象正坐在所述温度受控室。 </li><li>我f显示主体是女性，进行血清妊娠试验，以确保她是不是怀孕了。 注:在本研究中，内部审查委员会要求妊娠试验不到24小时前，被收购的PET / CT扫描。 </li></ol></li><li>之前进入恒温室<ol><li>有主题的变化转换成标准的医疗短裤和衬衫。删除袜子和鞋子。如果拍摄对象是女性，让运动胸罩不含任何金属的磨损。 </li><li>改变成标准衣物后测量被检者的身高，体重和腰围测量。 </li><li>使用舌下温度计测量受验者的体温。 </li></ol></li><li>在温控室<ol><li>指示受试者进入温度受控室。让拍摄对象静静的坐着不执行任何可能改变体温活动， 如运动，打字，或入睡。 </l我&gt; <li>坐在房间1小时后，用舌下温度计再次测量体温。 </li><li>上，在温度受控室的第一个小时后，PET-CT扫描天，有通过第四端口一个放射技术人员施用注射氟脱氧（18F-FDG）的。注入0.14毫居里/千克（约10毫居里70千克主题）的18 F-FDG。计算基于主题比重确切剂量。 </li><li>坐在所述温度受控室的第二小时后，用舌下温度计再次测量体温。 注意:与冷的MRI天后，用冷背心是不必要的冷PET-CT天因为18F-FDG示踪剂摄取到活化的BAT小时交示踪剂注射期间。示踪剂不会离开组织即使被摄体变得温暖，因为他/她被运到扫描仪。因此，由于它能够检测的ACTIVAT存在编BAT上即使BAT不保持有效的PET-CT扫描期间在PET-CT图像，冷背心是没有必要的。 </li><li> 2小时后，在温度受控室，输送在轮椅与PET-CT扫描仪的主题。使用轮椅，以保持在一个轻松，久坐不动的状态的问题，并尽量减少任何"升温"，从走路可能发生的。此外，使用轮椅有助于避免在PET示踪剂的任何摄取到骨骼肌，虽然它可能会是最小的。 </li></ol></li><li> PET-CT采集协议<ol><li>收购上发现STE PET / CT扫描PET-CT扫描（STE代表见和治疗精英）。 </li><li>定位在床的受试者在仰卧位置首先进入扫描头。 </li><li>一旦躺着，已受试者地方两臂内类似于枕套一个袋子，并且降低臂到主体的任一侧。这有助于确保在肩期间都定位在一个类似的方式MRI和PET / CT检查，这使得图像配准更容易。 注:观点的PET / CT显像领域从头部到大腿中部的7-9层位置的表冠盖，根据被摄物体的高度（每床位置2分钟）。推荐PET-CT参数列于表2中 。 </li></ol></li></ol> 6. MRI后处理<ol><li>保存实部和虚MR图像对通过MRI测量的离线工艺加工信号是与两个大小和方向，可以被表示为复数与实部和虚部的矢量量。在临床上，通常显示的大小的图像。然而，复杂的信息，需要用于处理入脂肪和水的图像。 </li><li>执行三维水/脂肪分离和基于多尺度整体图像优化算法45用C ++实现为每个单独的片叠，R 2 *估计。脂肪是用9峰建模<s<html>达&gt; 46。 </li><li>丢弃每4-回波串的第一回声，以避免在复杂的水发信号模型势涡流的污染。 </li></ol> 7. PET-CT后处理<ol><li>负载的CT DICOM数据到MATLAB和通过施加扫描器提供的重新调整值的数据值转换为亨斯菲尔德单位（HU）。 </li><li>加载的PET DICOM数据到MATLAB中，并转换为使用下式标准摄取值（SUV）: <img alt="式（1）" fo:content-width="3in" src="/files/ftp_upload/52415/52415eq1.jpg" /> 其中，"像素值"是在该像素位置的DICOM文件中存储的值。 <img alt="公式2" fo:content-width="3in" src="/files/ftp_upload/52415/52415eq2.jpg" /> 注:PET示踪剂活性的放射性核素的总剂量，并且可以从图像的元数据（DICOM头文件）被读取。 .JPG"/&gt; </li><li>内插的PET数据，以具有相同的尺寸的CT数据。 <ol><li>因为PET和CT图像与相同的切片厚度获得，在XY平面内使用一个2维样条函数进行内插。 </li></ol></li></ol> 8.数据后处理<ol><li>分析图像，使用刚体配准算法47通过半自动化的方法，在内部开发的3平面视图软件来验证登记的所有三个维度共同注册所有4图像体积为每个主题。 </li><li>由于与登记在所有四个时间点的整个图像体积的困难，集中登记上覆盖颈部到肺部的顶点的区域。在进一步的数据处理只能使用注册成功的区域。 </li><li>下面图像配准，加载FWMRI，CT HU和PET SUV数据到MATLAB和使用，定义感兴趣BAT地区。 注:类似于以前公共区域ished方法使用的PET的SUV和CT胡值，要考虑的最佳可行掩模的一部分区分BAT的19,25,48，图像中的每个体素，必须满足以下条件:（1），HU值落入的范围:-200 &lt;胡&lt;-1，在两个冷热CT扫描; （2）SUV&gt; 2.0冰冷的PET扫描; （3）的SUV信号分数[（冷SUV）/（冷的SUV +暖SUV）]&gt; 0.55， 即 ，冷的PET扫描必须产生在该体素观察到的SUV信号总数的55％以上;和（4）仅含有从MRI扫描，在那里大津算法49用于前景像素分类的前景像素。 </li><li>如果一个像素满足所有这些标准，包括BAT身份的二元面具体素。 </li><li>适用于以下二进制形态的步骤。 <ol><li>创建的矩阵相同大小的图像被处理。在新的矩阵中的每个空间位置是其所有相邻的邻居，在二进制的BAT掩模，包括对角线的3D总和。在和最大S嗯是26。 </li><li>阈值这个新的矩阵，包括与15或更多的3D邻居只能地点。此矩阵随后形成最终的二进制掩模的BAT。 注意:这些规则是足以段BAT组织，并且没有进一步的修改，以在掩模必须消除非BAT体素。这形成PET-CT切片逐片掩模在共注册肩区域确认的BAT。 </li></ol></li><li>敷面膜的所有共同注册的图像获取SUV，HU，发信号分数（FSF）和R 2 *值在BAT地区来说，无论是寒冷和温暖的扫描。 </li></ol>

The authors declare that they have no competing financial interests or other conflicts of interests.

所描述的研究协议被设计为使用两个热中性和冷活化PET / CT给受试者特定基础上自动段的BAT仓库。的利益，这些自动生成的区域可以被应用到已经被共同登记到同一检体的PET / CT扫描既适温和冷启动MRI扫描。尽我们所知，这是第一个研究后对同一健康成人志愿者适温和冷启动条件来执行MRI和PET / CT。这里所描述的过程需要四次访问，有一个成像会议上的每一天进行。通过使用该方法进一步分析，这?...

由于全球肥胖的显着上升，有旨在了解能量平衡研究领域的兴趣增加。肥胖可能导致昂贵的和破坏性的医疗条件，如糖 ​​尿病，肝脏疾病，心血管疾病和癌症，使得它关注的公共卫生1显著区域。研究的一个领域，旨在了解能量摄入的能量消耗与平衡是棕色脂肪组织或BAT的研究。虽然被称为脂肪组织，BAT不同于更普通的白色脂肪组织（WAT）在许多方面2。的白色脂肪细胞的功能是存储在每单元单个大脂质液泡甘油三酯，并在需要时释放这些甘油三酯作为能量来源进入血流。在一个非常不同的方式，褐色脂肪细胞的功能是产生热量。通过它发生这种情况的一个机制是通过受寒。这将导致增加sympathetiÇ神经系统的活动，这反过来又激活BAT。当被激活时，褐色脂肪细胞产生的热量。要做到这一点，它们使用包含在每个单元中的许多小脂质空泡的甘油三酯，并通过解偶联蛋白在丰富的线粒体中存在1（UCP1），转换甘油三酯代谢底物，而不产生ATP，从而导致熵损失作为发热体。作为存储在小脂质液泡的甘油三酯被耗尽时，脂肪细胞占用葡萄糖和甘油三酯存在于血液流3。 9 -在研究的BAT的兴趣大大近年来，由于其向非颤抖生热，其在调节体内的能量消耗的作用，和BAT和肥胖3之间的电势相反的关系的贡献增加。此外，最近的动物研究表明，BAT中清除甘油三酯和葡萄糖˚F起着关键的作用ROM中的血液流，尤其是以下的高脂肪膳食摄取10,11。然而，大多数的我们所知道的BAT是研究小型哺乳动物，其中包含BAT 4,9,12许多车厂的结果- 15。尽管一些早期的研究16 - 18，BAT在人体中的存在是普遍认为近期削弱随着年龄的增长，直到当研究人类BAT兴趣一直延续。最近的研究表明，相对少量的BAT持续到成年期19 - 24。一个附加的限制因素，以学习的BAT是除了活组织检查和组织染色，用于检测的BAT当前被接受的明确的方法是（18）F-氟（18 F-FDG）正电子发射断层扫描（PET）。现代PET扫描仪典型地结合了计算机断层摄影（CT）扫描仪。当冷暴露激活，BAT占用18 </s向上&gt; F-FDG的放射性示踪剂，这是葡萄糖代谢类似物，并在PET图像变得可见，在比较的18 F-FDG摄取的低得多的水平时BAT处于非活动状态20,21,23,25。在PET-CT扫描仪的帮助下，PET考试期间获得的CT图像提供解剖信息的组织与最高的18架F-FDG摄取之间的区别。此使用的PET-CT成像暴露受电离辐射（由PET主要是​​，尽管从CT扫描的剂量是不可忽略的），因此对BAT检测不期望的方法。 虽然英美烟草在健康成人的研究不断增多，人类最近的BAT的研究主要局限于回顾性PET-CT研究19,25，人类婴儿尸体26,27，谁已经被送往医院接受人体青少年其他原因27 - 30，和健康成人的几个人的研究31 - 35。之一的儿童和回顾性研究的两项研究的挑战之一是改变的结果的可能性，当研究的患者人群是谁病，这可能影响的BAT。此外，由于葡萄糖不能BAT 36的优选的燃料源，PET研究可能不总是检测活化的BAT，并因此可能underrepresent BAT的存在下进行。在研究的BAT与生物医学成像的另一个困难是与执行图像分割，以限定组织仓库的边界。目前，BAT在人类研究中的分段常依赖于某种程度的手动图像分割的，因此容易受到误认BAT车厂，以及间信变性。 由于这些挑战，可靠的空间映射技术，可以从WAT分布区分BAT，随着自动化的分割方法，将为调查提供了强大的新的醇与学习BAT。磁共振成像（MRI）具有用于识别，空间映射，和BAT的体积定量的能力，并且不象现有的混合型PET-CT成像的方法，其中包括一个放射性剂量为成像对象，MRI不涉及电离辐射，可以安全地使用反反复复。识别和利用MRI可以对临床内分泌学一个戏剧性的积极影响和追求肥胖研究的新途径量化BAT的能力。以前脂肪水MRI（FWMRI）BAT在小鼠和人类的研究表明，脂肪-信号-级分（FSF）BAT的是在40-80％的脂肪的范围内，而WAT是90％以上的脂肪15,26 27。因此，我们假设，这种定量​​FWMRI度量，与其他定量磁共振度量相结合，可用于在以后的工作，以可视化和量化的BAT仓库在人类。这将为研究团体与该研究BAT的影响力的有力工具上的满足不使用电离辐射abolism和能量消耗。 我们的研究小组一直在研究BAT在成年人在过去的三年。在使用MRI调查涉嫌BAT在一个成人受到我们的第一次公开演讲发生在2012年2月举行的国际学会磁共振医学（ISMRM）脂肪水分离车间在加州长滩37。两个月后，我们组提出FSF值怀疑BAT在两个成年人在20 日年度ISMRM在2012年4月在澳大利亚墨尔本38会议。一年后，在21年的ISMRM在2013年4月在盐湖城，犹他州会议，在这个手稿中描述的协议，被用于第一个（在我们所知）的PET-MRI确诊量化公开演讲BAT在成年人受试者39。具体而言，我们提出证据表明previouslŸ怀疑BAT被证实同时使用冷启动和热中性18 F-FDG PET-CT显像是激活BAT。自从2013年，我们的健康成年人受试者的队列适温和冷启动条件下成像与MRI和PET / CT已扩大到20多个科目最近在研讨会上提出，2014年二月统计调查结果"探索布朗脂肪的作用在人类"主办的美国国立卫生研究院NIDDK 40。具体地讲，我们报道FWMRI FSF和R 2 *在由18F-FDG PET-CT在成年人中，可确认在BAT的ROI锁骨BAT的区域缓和特性利用自动分割算法基于冷启动和热中性PET-CT划定扫描。最近，我们提出了温度映射的18架F-FDG PET-CT在采用先进的FWMRI测温41,42成人证实BAT结果。 这里的程序提出收购两者兼而有之MRI和关于同一主题的18架F-FDG PET-CT扫描，每次曝光既冷启动和热中性条件后。冷启动和热中性18 F-FDG PET-CT扫描用于创建兴趣分段自动BAT的区域（投资回报），主题特定的基础上。这些BAT的ROI，然后应用到共同注册的MRI扫描来测量MRI性能，在PET-CT证实BAT。 此协议的一个限制是，暴露受试者要么暖或冷的刺激时所使用的空气温度是为每一个主题是一致的。这是一个限制，因为在每个受试者经历感温或冷却的温度可以不同。因此，通过运行一个试验会议期间，空气温度被调节，以适应个体的反应，然后在热中性和冷激活协议利用这些温度下，它可能是能够获得更好的响应从褐色脂肪组织。

<table><tbody><tr><td>MRI</td><td>Philips</td><td>Achieva 3T</td><td></td></tr><tr><td>MRI Torso-XL coil</td><td>Philips</td><td>Philips SENSE XL Torso coil 16-elements</td><td></td></tr><tr><td>MRI X-tend Table</td><td>X-Tend</td><td>X-tend table, Acieva 3T compatible</td><td></td></tr><tr><td>X-tend armsupport</td><td>X-Tend</td><td>X-tend, accessories</td><td></td></tr><tr><td>X-tend fabricsling</td><td>X-Tend</td><td>X-tend, accessories</td><td></td></tr><tr><td>PET/CT</td><td>GE</td><td>Discovery STE</td><td></td></tr><tr><td>Portable A/C Unit</td><td>Soleus Air</td><td>XL-140, 14000 BTU</td><td></td></tr><tr><td>Floor fan</td><td>Lasko Pedestal Fan</td><td>2527</td><td></td></tr><tr><td>Portable Heater</td><td>Lasko Ceramic Air</td><td>5536</td><td></td></tr><tr><td>Chair</td><td>Winco Lifecare Recliner</td><td>585</td><td></td></tr><tr><td>Sublingual Thermometer</td><td>WelchAllyn</td><td>SureTemp Plus 690</td><td></td></tr><tr><td>Cold vest</td><td>Polar Products</td><td>Cool58 #PCVZ</td><td></td></tr><tr><td>Thermal IR Camera</td><td>FLUKE</td><td>TIR-125</td><td></td></tr></tbody></table>

human brown adipose tissue depots automatically segmented by positron emission tomography/computed tomography and registered magnetic resonance images

可靠地鉴别由其他组织中褐色脂肪组织（BAT），使用非侵入性的成像方法是朝向在人类研究的BAT的一个重要步骤。检测BAT通常由注射放射性示踪剂（18）F-氟脱氧（18F-FDG）成脂肪组织仓库的摄取证实，通过正电子发射断层扫描曝光受试者对冷刺激后测量/计算机断层扫描（PET-CT）扫描。脂肪 - 水分离的磁共振成像（MRI）具有区分的BAT，而无需使用放射性示踪物的能力。迄今为止，BAT在成年人的MRI尚未共同注册用冷活化PET-CT。因此，该协议使用（18）F-FDG PET-CT扫描，以自动生成一个BAT掩模，然后将其施加到共同注册同一受试者的MRI扫描。这种方法使英美烟草定量MRI性能测量没有手动分割。 BAT面具从两个PE创建T型CT扫描:曝光2小时要么适温（TN）（24℃）或冷活化（CA）（17℃）的条件之后。在TN和CA的PET-CT扫描被注册，并在PET标准摄取和CT的Hounsfield值用于创建仅包含的BAT的掩模。 CA和TN MRI扫描也可以获得对同一主题和注册的PET-CT扫描，以便将自动定义BAT规则范围内建立定量MRI性能。这种方法的一个优点是，所述分割是完全自动的，并且用于鉴定活化的BAT（PET-CT）的广为接受的方法的基础上。建立使用该协议可以作为基础的MRI仅BAT检查，避免与PET-CT相关联的辐射BAT的定量磁共振成像性能。

关于同一主题的收购MRI和PET-CT扫描，并在所有的扫描进行联合注册使英美烟草定量MRI指标可靠的测量。 图1显示了未经处理的温暖（TN）和冷（CA）PET-CT和MRI扫描从一个主题。通过获得两个TN和CA的PET-CT数据，因此能够通过增大（18）F-FDG摄取明确区分冷活化的BAT仓库。后共登记所有四个扫描（图2和3），它可以创建使用从PET-CT图像衍生的标准，一个特定?...

Watch this Scientific Journal Video about Human Brown Adipose Tissue Depots Automatically Segmented by Positron Emission Tomography/Computed Tomography and Registered Magnetic Resonance Images at JoVE

Human Brown Adipose Tissue Depots Automatically Segmented by Positron Emission Tomography/Computed Tomography and Registered Magnetic Resonance Images

这里介绍的方法，使用（18）F-氟脱氧（18F-FDG）正电子发射断层扫描/计算机断层扫描（PET-CT）和脂肪-水分离的磁共振成像（MRI），每个被扫描之后2小时暴露于热中性（24℃下），并以图中成年人受试者褐色脂肪组织（BAT）寒冷条件（17℃）。

人类的褐色脂肪组织的仓库的正电子发射断层扫描/计算机断层扫描自动分段及注册磁共振图像

Reliably differentiating brown adipose tissue (BAT) from other tissues using a non-invasive imaging method is an important step toward studying BAT in ...

human-brown-adipose-tissue-depots-automatically-segmented-positron

Research

JoVE Journal

Medicine

12.1K 次观看.  Vanderbilt University. 这里介绍的方法，使用（18）F-氟脱氧（18F-FDG）正电子发射断层扫描/计算机断层扫描（PET-CT）和脂肪-水分离的磁共振成像（MRI），每个被扫描之后2小时暴露于热中性（24℃下），并以图中成年人受试者褐色脂肪组织（BAT）寒冷条件（17℃）。 

视频: Human Brown Adipose Tissue Depots Automatically Segmented by Positron Emission Tomography/Computed Tomography and Registered Magnetic Resonance Images

Basic Surgical Techniques in the G&ouml;ttingen Minipig: Intubation, Bladder Catheterization, Femoral Vessel Catheterization, and Transcardial Perfusion

The emergence of the G&ouml;ttingen minipig in research of topics such as neuroscience, toxicology, diabetes, obesity, and experimental surgery reflects the close resemblance of these animals to human anatomy and physiology 1-6.The size of the G&ouml;ttingen minipig permits the use of surgical equipment and advanced imaging modalities similar to those used in humans 6-8. The aim of this instructional video is to increase the awareness on the value of minipigs in biomedical research, by demonstrating how to perform tracheal intubation, transurethral bladder catheterization, femoral artery and vein catheterization, as well as transcardial perfusion. 
Endotracheal Intubation should be performed whenever a minipig undergoes general anesthesia, because it maintains a patent airway, permits assisted ventilation and protects the airways from aspirates. Transurethral bladder catheterization can provide useful information about about hydration state as well as renal and cardiovascular function during long surgical procedures. Furthermore, urinary catheterization can prevent contamination of delicate medico-technical equipment and painful bladder extension which may harm the animal and unnecessarily influence the experiment due to increased vagal tone and altered physiological parameters. Arterial and venous catheterization is useful for obtaining repeated blood samples and monitoring various physiological parameters. Catheterization of femoral vessels is preferable to catheterization of the neck vessels for ease of access, when performing experiments involving frame-based stereotaxic neurosurgery and brain imaging. When performing vessel catheterization in survival studies, strict aseptic technique must be employed to avoid infections6. Transcardial perfusion is the most effective fixation method, and yields preeminent results when preparing minipig organs for histology and histochemistry2,9. For more information about anesthesia, surgery and experimental techniques in swine in general we refer to Swindle 2007. Supplementary information about premedication and induction of anesthesia, assisted ventilation, analgesia, pre- and postoperative care of G&ouml;ttingen minipigs are available via the internet at <a href="http://www.minipigs.com">http://www.minipigs.com</a>10. For extensive information about porcine anatomy we refer to Nickel et al. Vol. 1-511.

Basic Surgical Techniques in the G&#246;ttingen Minipig: Intubation, Bladder Catheterization, Femoral Vessel Catheterization, and Transcardial Perfusion

The use of domestic and miniature pigs in science has increased significantly in recent years. By demonstrating how to perform intubation, transurethral bladder catheterization, femoral artery and vein catheterization, as well as transcardial perfusion, we aim to further increase the value of G&ouml;ttingen minipigs in biomedical research.

基本外科技术，在哥廷根微型猪：气管插管，膀胱导尿，股血管的导管和Transcardial灌注

The emergence of the G&ouml;ttingen minipig in research of topics such as neuroscience, toxicology, diabetes, obesity, and experimental surgery reflects ...

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 ...

Non-invasive Imaging and Analysis of Cerebral Ischemia in Living Rats Using Positron Emission Tomography with 18F-FDG

Stroke is the third leading cause of death among Americans 65 years of age or older1. The quality of life for patients who suffer from a stroke fails to return to normal in a large majority of patients2, which is mainly due to current lack of clinical treatment for acute stroke. This necessitates understanding the physiological effects of cerebral ischemia on brain tissue over time and is a major area of active research. Towards this end, experimental progress has been made using rats as a preclinical model for stroke, particularly, using non-invasive methods such as 18F-fluorodeoxyglucose (FDG) coupled with Positron Emission Tomography (PET) imaging3,10,17. Here we present a strategy for inducing cerebral ischemia in rats by middle cerebral artery occlusion (MCAO) that mimics focal cerebral ischemia in humans, and imaging its effects over 24 hr using FDG-PET coupled with X-ray computed tomography (CT) with an Albira PET-CT instrument. A VOI template atlas was subsequently fused to the cerebral rat data to enable a unbiased analysis of the brain and its sub-regions4. In addition, a method for 3D visualization of the FDG-PET-CT time course is presented. In summary, we present a detailed protocol for initiating, quantifying, and visualizing an induced ischemic stroke event in a living Sprague-Dawley rat in three dimensions using FDG-PET.

Non-invasive Imaging and Analysis of Cerebral Ischemia in Living Rats Using Positron Emission Tomography with 18F-FDG

Brain damage resulting from cerebral ischemia may be non-invasively imaged and studied in rats using pre-clinical positron emission tomography coupled with the injectable radioactive probe, 18F-fluorodeoxyglucose. Further, the use of modern software tools that include volume of interest (VOI) brain templates dramatically increase the quantitative information gleaned from these studies.

无创成像和脑缺血分析生活中的大鼠使用正电子发射断层扫描<sup&gt; 18</sup&gt; F-FDG

Stroke is the third leading cause of death among Americans 65 years of age or older1. The quality of life for patients who suffer from a stroke fails to ...

Cerenkov Luminescence Imaging of Interscapular Brown Adipose Tissue

Brown adipose tissue (BAT), widely known as a &#8220;good fat&#8221; plays pivotal roles for thermogenesis in mammals. This special tissue is closely related to metabolism and energy expenditure, and its dysfunction is one important contributor for obesity and diabetes. Contrary to previous belief, recent PET/CT imaging studies indicated the BAT depots are still present in human adults. PET imaging clearly shows that BAT has considerably high uptake of 18F-FDG under certain conditions. In this video report, we demonstrate that Cerenkov luminescence imaging (CLI) with 18F-FDG can be used to optically image BAT in small animals. BAT activation is observed after intraperitoneal injection of norepinephrine (NE) and cold treatment, and depression of BAT is induced by long anesthesia. Using multiple-filter Cerenkov luminescence imaging, spectral unmixing and 3D imaging reconstruction are demonstrated. Our results suggest that CLI with 18F-FDG is a practical technique for imaging BAT in small animals, and this technique can be used as a cheap, fast, and alternative imaging tool for BAT research.

In this video report, we show the application of Cerenkov Luminescence Imaging (CLI) for interscapular brown adipose tissue in mice under activated and depressed conditions.

肩胛间褐色脂肪组织的切伦科夫发光成像

Brown adipose tissue (BAT), widely known as a &#8220;good fat&#8221; plays pivotal roles for thermogenesis in mammals. This special tissue is closely ...

Localization, Identification, and Excision of Murine Adipose Depots

Obesity has increased dramatically in the last few decades and affects over one third of the adult US population. The economic effect of obesity in 2005 reached a staggering sum of $190.2 billion in direct medical costs alone. Obesity is a major risk factor for a wide host of diseases. Historically, little was known regarding adipose and its major and essential functions in the body. Brown and white adipose are the two main types of adipose but current literature has identified a new type of fat called brite or beige adipose. Research has shown that adipose depots have specific metabolic profiles and certain depots allow for a propensity for obesity and other related disorders. The goal of this protocol is to provide researchers the capacity to identify and excise adipose depots that will allow for the analysis of different factorial effects on adipose; as well as the beneficial or detrimental role adipose plays in disease and overall health. Isolation and excision of adipose depots allows investigators to look at gross morphological changes as well as histological changes. The adipose isolated can also be used for molecular studies to evaluate transcriptional and translational change or for in vitro experimentation to discover targets of interest and mechanisms of action. This technique is superior to other published techniques due to the design allowing for isolation of multiple depots with simplicity and minimal contamination.

Due to the drastic and negative connection between obesity and other comorbidities, research on the role adipose plays in disease and overall health is warranted. We present a protocol for the isolation and excision of adipose depots allowing for the study of adipose using in situ and in vitro methods.

本地化识别，切除脂肪小鼠油库，并

Obesity has increased dramatically in the last few decades and affects over one third of the adult US population. The economic effect of obesity in 2005 ...

Functional Imaging of Brown Fat in Mice with 18F-FDG micro-PET/CT

Brown adipose tissue (BAT) differs from white adipose tissue (WAT) by its discrete location and a brown-red color due to rich vascularization and high density of mitochondria. BAT plays a major role in energy expenditure and non-shivering thermogenesis in newborn mammals as well as the adults 1. BAT-mediated thermogenesis is highly regulated by the sympathetic nervous system, predominantly via &beta; adrenergic receptor 2, 3. Recent studies have shown that BAT activities in human adults are negatively correlated with body mass index (BMI) and other diabetic parameters 4-6. BAT has thus been proposed as a potential target for anti-obesity/anti-diabetes therapy focusing on modulation of energy balance 6-8. While several cold challenge-based positron emission tomography (PET) methods are established for detecting human BAT 9-13, there is essentially no standardized protocol for imaging and quantification of BAT in small animal models such as mice. Here we describe a robust PET/CT imaging method for functional assessment of BAT in mice. Briefly, adult C57BL/6J mice were cold treated under fasting conditions for a duration of 4 hours before they received one dose of 18F-Fluorodeoxyglucose (FDG). The mice were remained in the cold for one additional hour post FDG injection, and then scanned with a small animal-dedicated micro-PET/CT system. The acquired PET images were co-registered with the CT images for anatomical references and analyzed for FDG uptake in the interscapular BAT area to present BAT activity. This standardized cold-treatment and imaging protocol has been validated through testing BAT activities during pharmacological interventions, for example, the suppressed BAT activation by the treatment of &beta;-adrenoceptor antagonist propranolol 14, 15, or the enhanced BAT activation by &beta;3 agonist BRL37344 16. The method described here can be applied to screen for drugs/compounds that modulate BAT activity, or to identify genes/pathways that are involved in BAT development and regulation in various preclinical and basic studies.

Functional Imaging of Brown Fat in Mice with 18F-FDG micro-PET/CT

A method of functional imaging of mouse brown adipose tissue (BAT) is described in which cold-stimulated uptake of 18F-Fluorodeoxyglucose (FDG) in BAT is non-invasively assessed with a standardized micro-PET/CT protocol. This method is robust and sensitive to detect differences in BAT activities in mouse models.

功能成像在小鼠体内的棕色脂肪与FDG micro-PET/CT

Brown adipose tissue (BAT) differs from white adipose  tissue (WAT) by its discrete location and a brown-red color due to rich  vascularization and high ...

生物学

Whole Body and Regional Quantification of Active Human Brown Adipose Tissue Using 18F-FDG PET/CT

In endothermic animals, brown adipose tissue (BAT) is activated to produce heat for defending body temperature in response to cold. BAT&#39;s ability to expend energy has made it a potential target for novel therapies to ameliorate obesity and associated metabolic disorders in humans. Though this tissue has been well studied in small animals, BAT&#39;s thermogenic capacity in humans remains largely unknown due to the difficulties of measuring its volume, activity, and distribution. Identifying and quantifying active human BAT is commonly performed using 18F-Fluorodeoxyglucose (18F-FDG) positron emission tomography and computed tomography (PET/CT) scans following cold-exposure or pharmacological activation. Here we describe a detailed image-analysis approach to quantify total-body human BAT from 18F-FDG PET/CT scans using an open-source software. We demonstrate the drawing of user-specified regions of interest to identify metabolically active adipose tissue while avoiding common non-BAT tissues, to measure BAT volume and activity, and to further characterize its anatomical distribution. Although this rigorous approach is time-consuming, we believe it will ultimately provide a foundation to develop future automated BAT quantification algorithms.

Whole Body and Regional Quantification of Active Human Brown Adipose Tissue Using 18F-FDG PET/CT

Using free, open-source software, we have developed an analytical approach to quantify total and regional brown adipose tissue (BAT) volume and metabolic activity of BAT using 18F-FDG PET/CT.

18F-fdg Petct 对活性人棕色脂肪组织的全身和区域定量

In endothermic animals, brown adipose tissue (BAT) is activated to produce heat for defending body temperature in response to cold. BAT&#39;s ability to ...

Using a Combination of Indirect Calorimetry, Infrared Thermography, and Blood Glucose Levels to Measure Brown Adipose Tissue Thermogenesis in Humans

In mammals, brown adipose tissue (BAT) is activated rapidly in response to cold in order to maintain body temperature. Although BAT has been studied greatly in small animals, it is difficult to measure the activity of BAT in humans. Therefore, little is known about the heat-generating capacity and physiological significance of BAT in humans, including the degree to which components of the diet can activate BAT. This is due to the limitations in the currently most used method to assess the activation of BAT-radiolabeled glucose (fluorodeoxyglucose or 18FDG) measured by positron emission tomography-computerized tomography (PET-CT).
This method is usually performed in fasted subjects, as feeding induces glucose uptake by the muscles, which can mask the glucose uptake into the BAT. This paper describes a detailed protocol for quantifying total-body human energy expenditure and substrate utilization from BAT thermogenesis by combining indirect calorimetry, infrared thermography, and blood glucose monitoring in carbohydrate-loaded adult males. To characterize the physiological significance of BAT, measures of the impact of BAT activity on human health are critical. We demonstrate a protocol to achieve this by combining carbohydrate loading and indirect calorimetry with measurements of supraclavicular changes in temperature. This novel approach will help to understand the physiology and pharmacology of BAT thermogenesis in humans.

Here, we present a protocol to quantify the physiological significance of the impact of brown adipose tissue (BAT) activity on human metabolism. This is achieved by combining carbohydrate loading and indirect calorimetry with measurements of supraclavicular changes in temperature. This novel approach can help develop a pharmacological target for BAT thermogenesis in humans.

使用间接量热法、红外热成像和血糖水平的组合来测量人类棕色脂肪组织的产热

In mammals, brown adipose tissue (BAT) is activated rapidly in response to cold in order to maintain body temperature. Although BAT has been studied ...

Visualization and Quantification of Brown and Beige Adipose Tissues in Mice using [18F]FDG Micro-PET/MR Imaging

Brown and beige adipocytes are now recognized as potential therapeutic targets for obesity and metabolic syndromes. Non-invasive molecular imaging methods are essential to provide critical insights into these thermogenic adipose depots. Here, the protocol presents a PET/MR imaging-based method to evaluate the activity of brown and beige adipocytes in mouse interscapular brown adipose tissue (iBAT) and inguinal subcutaneous white adipose tissue (iWAT). Visualization and quantification of the thermogenic adipose depots were achieved using [18F]FDG, the non-metabolizable glucose analog, as the radiotracer, when combined with the precise anatomical information provided by MR imaging. The PET/MR imaging was conducted 7 days after cold acclimation and quantitation of [18F]FDG signal in different adipose depots was conducted to assess the relative mobilization of thermogenic adipose tissues. Removal of iBAT substantially increased cold-evoked [18F]FDG uptake in iWAT of the mice.

Visualization and Quantification of Brown and Beige Adipose Tissues in Mice using [18F]FDG Micro-PET/MR Imaging

Functional imaging and quantitation of thermogenic adipose depots in mice using a micro-PET/MR imaging-based approach.

使用[18F]FDG微PET / MR成像对小鼠中的棕色和米色脂肪组织进行可视化和定量

Brown and beige adipocytes are now recognized as potential therapeutic targets for obesity and metabolic syndromes. Non-invasive molecular imaging methods ...

Differentiation and Imaging of Brown Adipocytes from the Stromal Vascular Fraction of Interscapular Adipose Tissue from Newborn Mice

Brown adipose tissue (BAT) is only present in mammals and has a thermogenic function. Brown adipocytes are characterized by a multilocular cytoplasm with multiple lipid droplets, a central nucleus, a high mitochondrial content, and the expression of uncoupling protein 1 (UCP1). BAT has been proposed as a potential therapeutic target for obesity and its associated metabolic disorders due to its ability to dissipate metabolic energy as heat. To investigate BAT function and regulation, brown adipocyte culturing is indispensable. The present protocol optimizes tissue processing and cell differentiation for culturing brown adipocytes from newborn mice. Additionally, procedures for the imaging of differentiated adipocytes with both confocal immunofluorescence and transmission electron microscopy are shown. In the brown adipocytes differentiated with the techniques described herein, the major defining features of classical BAT are preserved, including high UCP1 levels, increased mitochondrial mass, and very close physical contact between the lipid droplets and mitochondria, making this method a valuable tool for BAT studies.

Preadipocytes are isolated from the stromal vascular fraction of interscapular brown adipose tissue from newborn mice and differentiated into cells that accumulate lipid droplets, express molecular markers, and show the mitochondrial morphology of mature brown adipocytes. These cells are further analyzed by immunofluorescence and transmission electron microscopy.

新生小鼠肩胛间脂肪组织基质血管部分棕色脂肪细胞的分化和成像

Brown adipose tissue (BAT) is only present in mammals and has a thermogenic function. Brown adipocytes are characterized by a multilocular cytoplasm with ...

人类的褐色脂肪组织的仓库的正电子发射断层扫描/计算机断层扫描自动分段及注册磁共振图像

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