Name: using digital image correlation to characterize local strains on vascular tissue specimens
Uploaded: 2016-01-24T14:00:00.000+00:00
Duration: 9 min 29 s
Description: Watch this Scientific Journal Video about Using Digital Image Correlation to Characterize Local Strains on Vascular Tissue Specimens at JoVE.com

软件和技术支持是礼貌的相关解决方案公司（www.correlatedsolutions.com）。

注:下述程序进行的，在南卡罗来纳大学哥伦比亚，南卡罗来纳州批准的机构动物护理和使用委员会的协议的一部分。 1.组织收购和解剖<ol><li>消毒前，组织剥离所有的外科手术工具。高压釜外科剪刀和细标准钳子以及15 psi的压力和121℃温度下15分钟下外科刀片。 </li><li>获取一组新鲜猪（7个月大的长白男性，60-70公斤）的肾脏具有完整主动脉从本地屠宰场。运输组织返回到冰水1％的磷酸盐缓冲盐水（PBS）溶液中的实验室。 </li><li>随即抵达时，隔离用手术剪刀和镊子周围组织的腹主动脉。 </li><li>使用50毫升注射器填充用PBS（pH7.2）中洗容器三次。使用剪刀和镊子，尽量恢复血管周围组织的POSSIBLE而不损害样品的完整性。 </li><li>锋利的刀片垂直地定位到容器的中间部分，并确保它是垂直于容器纵向轴线。通过应用与剃刀刀片的三个连续圆周切口创建每两个环样品具有大约20mm的宽度。 </li><li>锋利的刀片垂直地定位到一个环样品使得该刀片被定向在径向方向。施加急性力以产生一个径向切割，这会导致对于单轴机械测试的带状样品。将样品在100毫米的玻璃培养皿中，并淹没在PBS，直到表面斑点的应用。重复第二环样品。 </li></ol> 2.创建表面散斑<ol><li>喷枪连接到压阀。 </li><li>调整喷枪的喷嘴直径，得到60-100微米的斑点（适当范围喷嘴直径应从初步研究确定）。 </li><li>倒入约2mL黑色组织标记染料进入喷枪的重力给料机。 </li><li>将喷枪大约为0.5米处的样品。 </li><li>除去从培养皿的样品。下的100磅的喷雾压力喷洒在样品的内膜表面组织标记染料为约5秒。重复三次，以确保该散斑图案均匀地覆盖样品表面。 </li></ol>实验3.性能<ol><li>样品的每端连接到使用组织粘合剂的塑料条带（1厘米宽×1厘米长×0.5厘米厚）。广场上组织砧板样品。定位样品，使得其平放并用数字游标卡尺测量其尺寸。 </li><li>启动系统控制的机械测试。在系统控制主屏幕中，选择任务栏中的"设置"选项卡上的"波形"。 </li><li>广告机械测试仪的上部握于-4毫米（4毫米分机相对于在系统中所指定的初始位置）的仅有的位置。轻轻固定一根塑料条（附着到样品中3.1）到机械测试仪的上把手和让样品自由悬挂。用数显卡尺，以确保样品与上部把手之间的距离小于2毫米。 </li><li>手动调整下夹具的位置，以使样品的自由端可以在不扩展被固定。轻轻固定附着在样品进入机械试验机的下夹具的自由端的塑料条。 <ol><li>用数显卡尺，以确保在样品和下夹具之间的距离小于2毫米。零系统负载单元。测量样品的长度并以此作为基准长度为全球圆周菌株的计算。 </li></ol></li><li>进入机械测试协议。在吨使用的协议他示范嗣继承4单轴位移周期其中18％以0.01毫米/秒的位移速率延长样品的长度。 </li><li>间歇地喷洒在整个余下的测试协议样品的PBS，以确保它保持水合。 </li><li>安装摄像头（500万像素的摄像头100毫米的镜头，3.49微米像素尺寸），其上放置1.5 m的装载架三脚架。确保相机和样品表面是由相机设置为深度的最低可用字段和操纵其对准使得整个视野是在焦点垂直。 </li><li>打开图像捕捉软件。 </li><li>选择"PGR-2"的选项"选择系统"。 </li><li>选择项目的保存路径图像进行分析。 </li><li>单击"时代广场"图标，并指定采集间隔为5秒。 </li><li>调整镜头的曝光，数值孔径，聚焦以便获得样本的清晰视图。 </li><li>调整LED的位置，以提供样品足够的照明。 </li><li>点击在图像捕获软件的"开始"图标，以获得样品表面的图像。 </li><li>打开图像分析软件。 </li><li>导入所获得的图像。放大单个斑点，然后这个人的斑点内计数的像素数。 注:确定有代表性的黑色斑点。定义散斑尺寸上的斑点的具有类似的高值两侧像素之间的直线距离。对一个可接受的斑点尺寸，穿过一个典型斑点的宽度的像素数量应大于3个像素。改善该测量空间分辨率，大多数斑点应该有不超过5-7个像素横跨斑点的宽度，只要有可能。因此，典型的斑点为这种情况下将在最大线性尺寸之间10微米的最小和23微米的范围内。确定合适的子集尺寸，一个典型的子集应当具有跨过其宽度的至少3个白色和黑色的3斑点。如果一个典型斑点是5个像素中的线性尺寸，则每个31x31子集将是至少105微米的线性尺寸。子集的中心之间的间距应至少1/6的线性尺寸。因此，对于31x31子集大小，该距离为5个像素，代表18微米的直线距离。 </li><li>核实散斑的质量后，同时单击图像采集软件在系统中的"运行"图标和"开始"图标，开始测试。 </li><li>攻克了一系列使用相机和图像采集软件映像整个测试。 </li></ol>实验结束后4清理程序<ol><li>将在生物危害袋丢弃的样品，并关闭袋。通话环境健康与安全（EHS）在南卡罗来纳大学的系进行妥善处置。 </li><li>准备磷酸盐自由消毒剂溶液用洗涤剂消毒剂蒸馏水1:64稀释比。浸泡在该溶液中20分钟的外科手术工具。 </li><li>彻底冲洗4.2中描述的蒸馏水的项目。干燥用纸巾的工具，然后将它们喷雾用70％的乙醇溶液。再次用干纸巾的手术工具，并把它们放回手术工具箱。 </li></ol> 5.图像分析来测量局部应变场<ol><li>打开图像分析软件。 </li><li>点击"斑点图像"选项卡中，选择需要进行分析的所有图像。 </li><li>点击矩形工具和选择的在第一图像感兴趣区域。 </li><li>输入子集尺寸4​​1×41像素，步长5个像素。 </li><li>点击开始，在软件分析选项卡，选择插值优化的8-陷阱;选择的标准是零归平方差和子集的权重的选择，因为高斯。 </li><li>设置阈值选项作为默认在软件中。 </li><li>单击开始分析选项卡后处理子选项卡上。点击选项，应变计算和离开过滤器的大小和过滤器为默认的软件类型。选择张量型拉格朗日。 </li><li>选择数据选项卡，然后选择任何分析的图像的表面应变场的可视化。 </li></ol>

<ol>
	<li>Holzapfel, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biomechanics+of+soft+tissue.">Biomechanics of soft tissue.</a> The handbook of materials behavior models. 3, 1049-1063 (2001).</li><li>Vito, R. P., Dixon, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blood+vessel+constitutive+models-1995-2002.">Blood vessel constitutive models-1995-2002.</a> Annu Rev Biomed Eng. 5, 413-439 (2003).</li><li>Dodson, R. B., Martin, J. T., Hunter, K. S., Ferguson, V. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+hyperelastic+properties+for+umbilical+artery+in+preeclampsia+from+uniaxial+extension+tests.">Determination of hyperelastic properties for umbilical artery in preeclampsia from uniaxial extension tests.</a> Eur J Obstet Gynecol Reprod Biol. 169, 207-212 (2013).</li><li>Chuong, C. J., Fung, Y. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+residual+stresses+in+arteries.">On residual stresses in arteries.</a> J Biomech Eng. 108, 189-192 (1986).</li><li>Borschel, G. H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tissue+engineering+of+recellularized+small-diameter+vascular+grafts.">Tissue engineering of recellularized small-diameter vascular grafts.</a> Tissue Eng. 11, 778-786 (2005).</li><li>Wagenseil, J. E., Mecham, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vascular+extracellular+matrix+and+arterial+mechanics.">Vascular extracellular matrix and arterial mechanics.</a> Physiol Rev. 89, 957-989 (2009).</li><li>Holzapfel, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+material+models+for+arterial+walls+from+uniaxial+extension+tests+and+histological+structure.">Determination of material models for arterial walls from uniaxial extension tests and histological structure.</a> J Theor Biol. 238, 290-302 (2006).</li><li>Tanaka, T. T., Fung, Y. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Elastic+and+inelastic+properties+of+the+canine+aorta+and+their+variation+along+the+aortic+tree.">Elastic and inelastic properties of the canine aorta and their variation along the aortic tree.</a> J Biomech. 7, 357-370 (1974).</li><li>Sokolis, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Passive+mechanical+properties+and+structure+of+the+aorta:+segmental+analysis.">Passive mechanical properties and structure of the aorta: segmental analysis.</a> Acta physiologica. 190, 277-289 (2007).</li><li>Twal, W., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cellularized+Microcarriers+as+Adhesive+Building+Blocks+for+Fabrication+of+Tubular+Tissue+Constructs.">Cellularized Microcarriers as Adhesive Building Blocks for Fabrication of Tubular Tissue Constructs.</a> Ann Biomed Eng. , 1-12 (2013).</li><li>Shazly, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+Uniaxial+Ring+Test+of+Tissue+Engineered+Constructs.">On the Uniaxial Ring Test of Tissue Engineered Constructs.</a> Exp Mech. , 1-11 (2014).</li><li>Kim, J., Baek, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Circumferential+variations+of+mechanical+behavior+of+the+porcine+thoracic+aorta+during+the+inflation+test.">Circumferential variations of mechanical behavior of the porcine thoracic aorta during the inflation test.</a> J Biomech. 44, 1941-1947 (2011).</li><li>Li, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+material+parameters+of+the+two-dimensional+Holzapfel-Weizsacker+type+model+based+on+uniaxial+extension+data+of+arterial+walls.">Determination of material parameters of the two-dimensional Holzapfel-Weizsacker type model based on uniaxial extension data of arterial walls.</a> Comput Methods Biomech Biomed Engin. 16, 358-367 (2013).</li><li>Li, L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+the+material+parameters+of+four-fibre+family+model+based+on+uniaxial+extension+data+of+arterial+walls.">Determination of the material parameters of four-fibre family model based on uniaxial extension data of arterial walls.</a> Comput Methods Biomech Biomed Engin. 17, 695-703 (2014).</li><li>Hoeltzel, D. A., Altman, P., Buzard, K., Choe, K. I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Strip+extensiometry+for+comparison+of+the+mechanical+response+of+bovine,+rabbit,+and+human+corneas.">Strip extensiometry for comparison of the mechanical response of bovine, rabbit, and human corneas.</a> J Biomech Eng. 114, 202-215 (1992).</li><li>Guo, X., Kassab, G. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Variation+of+mechanical+properties+along+the+length+of+the+aorta+in+C57bl/6+mice.">Variation of mechanical properties along the length of the aorta in C57bl/6 mice.</a> Am J Physiol Heart Circ Physiol. 285, H2614-H2622 (2003).</li><li>Smutz, W., Drexler, M., Berglund, L., Growney, E., An, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Accuracy+of+a+video+strain+measurement+system.">Accuracy of a video strain measurement system.</a> J Biomech. 29, 813-817 (1996).</li><li>Genovese, K., Lee, Y. U., Lee, A. Y., Humphrey, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+improved+panoramic+digital+image+correlation+method+for+vascular+strain+analysis+and+material+characterization.">An improved panoramic digital image correlation method for vascular strain analysis and material characterization.</a> J Mech Behav Biomed Mater. 27, 132-142 (2013).</li><li>Wang, C. C., Deng, J. M., Ateshian, G. A., Hung, C. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+automated+approach+for+direct+measurement+of+two-dimensional+strain+distributions+within+articular+cartilage+under+unconfined+compression.">An automated approach for direct measurement of two-dimensional strain distributions within articular cartilage under unconfined compression.</a> J Biomech Eng. 124, 557-567 (2002).</li><li>Ning, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Deformation+measurements+and+material+property+estimation+of+mouse+carotid+artery+using+a+microstructure-based+constitutive+model.">Deformation measurements and material property estimation of mouse carotid artery using a microstructure-based constitutive model.</a> J Biomech Eng. 132, 121010 (2010).</li><li>Sutton, M. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Strain+field+measurements+on+mouse+carotid+arteries+using+microscopic+three-dimensional+digital+image+correlation.">Strain field measurements on mouse carotid arteries using microscopic three-dimensional digital image correlation.</a> J Biomed Mater Res A. 84, 178-190 (2008).</li><li>Sutton, M. A., Orteu, J. J., Schreier, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Image correlation for shape, motion and deformation measurements: basic concepts, theory and applications. , (2009).</li><li>Verhulp, E., van Rietbergen, B., Huiskes, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+three-dimensional+digital+image+correlation+technique+for+strain+measurements+in+microstructures.">A three-dimensional digital image correlation technique for strain measurements in microstructures.</a> J Biomech. 37, 1313-1320 (2004).</li><li>Wang, C. C., Deng, J. M., Ateshian, G. A., Hung, C. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+automated+approach+for+direct+measurement+of+two-dimensional+strain+distributions+within+articular+cartilage+under+unconfined+compression.">An automated approach for direct measurement of two-dimensional strain distributions within articular cartilage under unconfined compression.</a> Journal of Biomechanical Engineering. 124, 557-567 (2002).</li><li>Franck, C., Hong, S., Maskarinec, S., Tirrell, D., Ravichandran, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three-dimensional+full-field+measurements+of+large+deformations+in+soft+materials+using+confocal+microscopy+and+digital+volume+correlation.">Three-dimensional full-field measurements of large deformations in soft materials using confocal microscopy and digital volume correlation.</a> Exp Mech. 47, 427-438 (2007).</li><li>Garcia, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+study+and+constitutive+modelling+of+the+passive+mechanical+properties+of+the+porcine+carotid+artery+and+its+relation+to+histological+analysis:+Implications+in+animal+cardiovascular+device+trials.">Experimental study and constitutive modelling of the passive mechanical properties of the porcine carotid artery and its relation to histological analysis: Implications in animal cardiovascular device trials.</a> Med Eng Phys. 33, 665-676 (2011).</li><li>Miller, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=How+to+test+very+soft+biological+tissues+in+extension?.">How to test very soft biological tissues in extension?.</a> J Biomech. 34, 651-657 (2001).</li><li>Sutton, M. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Springer handbook of experimental solid mechanics. , 565-600 (2008).</li><li>Han, H. C., Fung, Y. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Longitudinal+strain+of+canine+and+porcine+aortas.">Longitudinal strain of canine and porcine aortas.</a> J Biomech. 28, 637-641 (1995).</li><li>Sokolis, D. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+passive+strain-energy+function+for+elastic+and+muscular+arteries:+correlation+of+material+parameters+with+histological+data.">A passive strain-energy function for elastic and muscular arteries: correlation of material parameters with histological data.</a> Med Biol Eng Comput. 48, 507-518 (2010).</li><li>Zhou, B., Wolf, L., Rachev, A., Shazly, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+structure-motivated+model+of+the+passive+mechanical+response+of+the+primary+porcine+renal+artery.">A structure-motivated model of the passive mechanical response of the primary porcine renal artery.</a> J Mech Med Biol. , (2013).</li><li>Zhou, B., Rachev, A., Shazly, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+biaxial+active+mechanical+properties+of+the+porcine+primary+renal+artery.">The biaxial active mechanical properties of the porcine primary renal artery.</a> J Mech Behav Biomed Mater. 48, 28-37 (2015).</li><li>Sommer, G., Holzapfel, G. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=3D+constitutive+modeling+of+the+biaxial+mechanical+response+of+intact+and+layer-dissected+human+carotid+arteries.">3D constitutive modeling of the biaxial mechanical response of intact and layer-dissected human carotid arteries.</a> J Mech Behav Biomed Mater. 5, 116-128 (2012).</li></ol>

作者有没有潜在的利益冲突。

尽管以前的研究已经使用了范围广泛的染料跟踪视频的方法来评估样本的应变18,20,21,23,24，我们现在的目标是提供一个全面的方法来夫妇单轴拉伸试验与2D-DIC的评估表面菌株对血管组织样品。具有高分辨率摄像机和内部图像分析软件，应变场可以在预定的表面区域内测量样品经历单轴加载。特别是血管组织的机械测试的相关性，所提出的技术可直接适用于评估平面双轴测试，从而能够识别的组成材料性能的表面张力。 为了便于数字图像相关分析，散斑图案被施加到样品表面上。用于斑点漆是一种组织标记染料容易附着到最软组织表面。为了实现对比度良好的质量和散斑图案，60-100微米的最佳散斑大小的适当的密度和0.5米喷雾距离通过调节喷枪的喷嘴直径和样品和喷枪之间的距离来实现的。所使用的斑点尺寸是直接关系到所得到的测量值23,25的分辨率。每个斑点具有由至少3-5个像素进行采样，以获得可接受的图像的相关性。给定的视图22毫米×18毫米字段和所利用的斑点大小，所呈现的实验的分辨率为9微米/像素。 为0.01毫米/秒的装载率用于机械测试，以便获得一系列的准静态变形平衡状态为血管组织26,27。由于相机和高保真称重传感器都极其敏感的振动，应该有在实验期间最小的运动;即使小，刚体摄像头/样运动可能会出现和W不良变乱2D-DIC为基础的测量。同样，样品的变形可以导致组织脱水，从而认为PBS通过检测施加到推动2D-DIC的准确性是很重要的。 对于2D-DIC，所需规格包括子集的大小和图像匹配算法22所使用的步长。为了获得具有可忽略的偏差精确的结果，至少3个黑和3白色斑点应存在于每个子集，以由至少3-5个像素的每个采样斑点。在输出每个数据点提供的信息的平均值对应于子集大小（41x41像素），作为实验的空间分辨率的盒。在步骤大小而言两个数据点之间的距离为5个像素在该实验。为了最大限度地提高精度的斑点的位移/表面应变测量，一个8抽头样条内插方法被应用到获得精确的，子像素的强度值。 8抽头甲基外径具有稍微更高的精度获得的菌株相比，使用一个4抽头或6分接头内插滤波器获得的结果。相关标准"归一化平方差"入选的匹配，因为它不受规模的变化照明（例如，当一个畸形的子集，比基准亮30％）。这种选择是在软件默认选择，通常提供的灵活性的最佳组合和结果28。子集的加权，控制如何子集内的像素被加权的匹配处理中，被选择为高斯。具有均匀的重量，所述子集内的每个像素被均等地考虑;高斯权提供空间分辨率和位移分辨率的最佳组合。 表面应变场的变异系数分别计算与内部图像分析软件和用于量化应变异质性程度。该系数应变场的同时在圆周和纵向方向变化ficient随着全球周向应变，这已经在对其他血管组织类型（未发表的结果）类似的机械试验已经先前观察降低。在此基础上持续的趋势，这是合理的期望，表面应变场可以充分均质上述一些关键的延伸度，使得全球和本地的测量收敛。但是，很可能，这个临界值是组织 - 和样本特异性，从而支持采用局部应变测量的准确识别构成材料的特性。 一些局限性，必须考虑我们提出的方法和结果的正确解释。我们规定的范围适中全球圆周应变，从而在两个周向和纵向方向上我们实现了局部应变幅度均显著降低<html>比见于体内的值。此外，我们评估下一个采样取向单轴机械响应，并因此产生数据不足，以确定血管组织29,30构成材料的特性。但是，我们的目的不是要进行猪的主动脉的综合力学分析，而是要表现出一个试验性协议，以夫妻2D-DIC以单轴机械测试的软组织。本文中所呈现的技术可以容易地扩展到双轴机械测试，从而对血管组织31-33的构机械性能的定量。的2D-DIC方法仅捕获对应于样品表面的平面应变场。当检体变形挤出平面外，或在标本是一个非平面的几何形状（例如，血管），立体视觉影像和3D-DIC技术可应用于综合应变测量23,25。 核苷酸"&gt;综上所述，本手稿提供的方法的详细信息，以整合单轴拉伸测试和数字图像相关来表征天然血管组织的机械响应。在本研究中提出的方法，可以容易地适用于其他天然的机械特性和工程化软组织以及软水凝胶/聚合物材料，并且是特别有用的，当样品表面应变场呈现期间机械测试显著异质性。

研究丰富的历史跨度超过50年一直专注于量化血管组织的力学性能。这些研究使我们更好地理解这两种生理和病理血管行为，评价血管内装置的功效/相容性，并有助于在设计和工程化的血管的制造构建1-6提供了基础。软组织和它们的机械性能的构模拟的机械响应的精确测量固有地由于机械异质性，各向异性，和非线性大多数组织类型呈现挑战。此外，实验测量往往是由在样品握接口在机械测试的过程中引入本地复杂性（即，弯曲，摩擦，应力集中，撕裂）和机械性能的不可避免的过渡一旦组织被从活的动物切除混淆。 &lt;/ P&gt; 甲单轴拉伸实验是，可以在由固体材料制成的试样进行的最简单的机械试验中，并且通常被用来评估血管组织的机械响应。这些实验的结果提供对本地和工程化的组织来源有用的初步信息，并可以用来比较对血管壁7-11的力学行为的某些治疗，疾病状态，或药理学化合物的影响。 典型地样品上具有相对均匀的几何形状，这是最常见的狗骨或环状7,8,12-14软组织的单轴机械测试。然而，从这些理想化的几何形状显著出发，可能会发生由于与组织解剖，分离，并且测试系统内的夹紧相关的挑战。任何非均匀性的几何形状将最终引起异构应力和应变字段当样品进行单轴延伸，与异质取决于实际样品的形状，以及样本大小（相对于夹具）与材料9,15,16的机械性能的程度。当字段非均质性是显著，根据相对的抓握姿势样品应变的计算是不准确的，因此，以评估机械性能不足的基础。 视频分析系统已被广泛用于软组织应变测量，通常使用施加在试样表面17,18高对比染料标记。数字图像相关，光学计量技术，该技术通过变形之前和之后在试样的表面比较灰度强度值测量全视野表面应变，已经与视频一起使用的软组织19-21分析。相比interferometr有数字图像相关的几个优点集成电路的方法可用于测量。首先，作为以非接触测量技术，它最大限度地减少修改由于在该测量系统的影响的检体的方式的材料性质的混杂影响。第二，它需要一个更严格的测定环境，并具有较宽范围的灵敏度和分辨率比其它方法的。第三，赋有摄像视一个全视场的能力，这种技术可以表征的平均及本地机械响应。对于该方法的详细说明，我们鼓励读者通过萨顿22看的书。 以获得在试样表面的应变场，一个二维数字图像相关技术（2D-DIC）都可以使用。简言之，样品的图像被捕获在卸载和装载各种状态。第一图像被划分为称为子集（M×M像素）的小方块形成网状用于随后的计算2D应变场。使用图像匹配算法得到的变形样品每平方米的位置。每个正方形的运动，然后追踪，图像逐图像，得到随后可用于通过各种方法，包括多项式拟合或有限元插值导出变形梯度和菌株位移字段。在本手稿中，我们提供了通过整合单轴拉伸试验和2D-DIC评估原生血管组织表面应变场的详细方法。

<table><tbody><tr><td>Uniaxial tensile mechanical tester</td><td>Enduratec</td><td>3230 AT/HR</td><td></td></tr><tr><td>Blue tissue marking dye</td><td>http://www.ebay.com/itm/Tissue-Marking-Dye-in-Bottles-2oz-Bottle-1-ea-/201193551510?pt=LH_DefaultDomain_0&amp;amp;hash=item2ed811f696</td><td></td><td></td></tr><tr><td>Sprayer</td><td>Anest-iwata</td><td>CM-B</td><td>Custom Micron B</td></tr><tr><td>Camera</td><td>Point Grey</td><td>GS2-GE-50S5M-C</td><td></td></tr><tr><td>Lens</td><td>Tokina</td><td>AT-X M100</td><td></td></tr><tr><td>Vascular tissue</td><td>Caughman Inc</td><td></td><td></td></tr><tr><td>0.9% Sodium Chloride Injection PBS</td><td>BAXTER HEALTHCARE CORP.</td><td></td><td></td></tr><tr><td>Vic_snap</td><td>Correlated Solutions</td><td></td><td></td></tr><tr><td>Vic_2D</td><td>Correlated Solutions</td><td></td><td></td></tr><tr><td>Wintest 4.1</td><td>Bose ElectroForce</td><td></td><td></td></tr><tr><td>Tissue adhesive</td><td>&amp;nbsp;3M Vetbond&amp;nbsp;</td><td>1469SB</td><td></td></tr><tr><td>Disinfectant&amp;nbsp;</td><td>Fisher Scientific</td><td>04-355-13</td><td>Decon BDD Bacdown Detergent Disinfectant</td></tr></tbody></table>

using digital image correlation to characterize local strains on vascular tissue specimens

Characterization of the mechanical behavior of biological and engineered soft tissues is a central component of fundamental biomedical research and product development. Stress-strain relationships are typically obtained from mechanical testing data to enable comparative assessment among samples and in some cases identification of constitutive mechanical properties. However, errors may be introduced through the use of average strain measures, as significant heterogeneity in the strain field may result from geometrical non-uniformity of the sample and stress concentrations induced by mounting/gripping of soft tissues within the test system. When strain field heterogeneity is significant, accurate assessment of the sample mechanical response requires measurement of local strains. This study demonstrates a novel biomechanical testing protocol for calculating local surface strains using a mechanical testing device coupled with a high resolution camera and a digital image correlation technique. A series of sample surface images are acquired and then analyzed to quantify the local surface strain of a vascular tissue specimen subjected to ramped uniaxial loading. This approach can improve accuracy in experimental vascular biomechanics and has potential for broader use among other native soft tissues, engineered soft tissues, and soft hydrogel/polymeric materials. In the video, we demonstrate how to set up the system components and perform a complete experiment on native vascular tissue.

从血管组织倾斜的单轴拉伸试验获得的机械数据由负载与在给定的位移速率应用的样本位移关系。在这项研究中，2D-DIC与单轴机械测试结合用于测量在以各种变形的状态正交的方向的样品表面应变场。血管组织的粘弹性性质是通过在之前机械预处理负载 - 位移曲线的显着程度的​​滞后表现。以促进机械测试的再现性，将获得的弹性机械响应，所述组织是通过几个装载-卸载循环预处理其中滞后逐渐减小（ 图1）。尽管非常仔细的样品制备和安装，2D-DIC的测量表明，所得到的内膜表面应变场是在这两个高度异质性<html>周向和纵向的方向。正如预期的那样，当地的圆周应变值随应用的样本位移。异质在圆周应变图案通常产生值较低靠近样品的中心相比靠近样品握接口，反映本地菌株握把的效果（ 图2）。在纵向上，在样品内膜表面所得到的非均匀压缩应变增加，因为样品是逐渐扩展，并将所得应变场表现异质性的更明显的程度相比，圆周方向（ 图3）。分别计算在正交方向的表面应变场的变化（CV）的系数，以反映字段的异质性，在选择的实验状态的程度，并且发现单调增加的示例扩展（表1）降低。 jove_content"FO:保持together.within页="1"&gt; <img alt="图1" src="/files/ftp_upload/53625/53625fig1.jpg" /> 图1.单轴拉伸试验血管组织样本的实验预处理，一个长方形的样品预处理有三个装卸周期，以获得可重复的弹性响应。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53625/53625fig1large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图2" src="/files/ftp_upload/53625/53625fig2.jpg" /> 图 感兴趣的样品区域内 。2. 周向应变场 。 （ 一）有斑点样内膜表面，并确定感兴趣的领域有代表性的例子。 （二）地方圆周应变εYY（％）的利息增加了识别的区域内应用全球圆周应变级别（从1.6％提高到9％〜18％，左到右）。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53625/53625fig2large.jpg" target="_blank">请点击此处查看该图的放大版本。</a> <img alt="图3" src="/files/ftp_upload/53625/53625fig3.jpg" /> 感兴趣的样品区域内 如图3 纵向应变场。（A）的样品斑点内膜表面，并确定了感兴趣的区域代表的例子。 （ 二）局部纵向应变εXX（％）利息确定区域内的增大施加全球圆周应变级别（从1.6％提高到9％〜18％，左到右）。 <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/53625/53625fig3large.jpg" target="_blank">请点击此处查看更大的版本这个数字。</a> <tableFO:保持together.within页="1"&gt; <tbody><tr><td> 全球圆周应变[％] </td><td> 简历εYY（％） </td><td> 简历εXX（％） </td></tr><tr><td> 1.6 </td><td> 11.8 </td><td> 28.1 </td></tr><tr><td> 9 </td><td> 7.4 </td><td> 25.1 </td></tr><tr><td> 18.0 </td><td> 5.6 </td><td> 20.7 </td></tr></tbody></table> 表1.系数的应变场的变化 。样品内膜表面应变场的变化（CV）的两个周（ε 日）和纵向（εXX），在选择应用全球圆周应变水平方向的系数。

Watch this Scientific Journal Video about Using Digital Image Correlation to Characterize Local Strains on Vascular Tissue Specimens at JoVE.com

Using Digital Image Correlation to Characterize Local Strains on Vascular Tissue Specimens

利用数字图像相关表征的血管组织标本本地菌株

We describe the use of digital image correlation to characterize the local surface strain field on vascular tissue samples subjected to uniaxial tensile testing. These measurements facilitate precise quantification of the sample mechanical response and the generation of constitutive stress-strain relations.

Characterization of the mechanical behavior of biological and engineered soft tissues is a central component of fundamental biomedical research and ...

using-digital-image-correlation-to-characterize-local-strains-on

Nanyang Technological University

Research

JoVE Journal

Biology

9.4K 次观看.  University of South Carolina. We describe the use of digital image correlation to characterize the local surface strain field on vascular tissue samples subjected to uniaxial tensile testing. These measurements facilitate precise quantification of the sample mechanical response and the generation of constitutive stress-strain relations.

视频: Using Digital Image Correlation to Characterize Local Strains on Vascular Tissue Specimens

Monitoring the Wall Mechanics During Stent Deployment in a Vessel

Clinical trials have reported different restenosis rates for various stent designs1. It is speculated that stent-induced strain concentrations on the arterial wall lead to tissue injury, which initiates restenosis2-7. This hypothesis needs further investigations including better quantifications of non-uniform strain distribution on the artery following stent implantation. A non-contact surface strain measurement method for the stented artery is presented in this work. ARAMIS stereo optical surface strain measurement system uses two optical high speed cameras to capture the motion of each reference point, and resolve three dimensional strains over the deforming surface8,9. As a mesh stent is deployed into a latex vessel with a random contrasting pattern sprayed or drawn on its outer surface, the surface strain is recorded at every instant of the deformation. The calculated strain distributions can then be used to understand the local lesion response, validate the computational models, and formulate hypotheses for further in vivo study.

Stent-induced arterial strain distributions are characterized using an optical surface strain measurement system. This visualization technique is used to gain insights into the impact of stent implantation on the host vessel.

在一个容器的支架部署在监测的墙力学

Clinical trials have reported different restenosis rates for various stent designs1. It is speculated that stent-induced strain concentrations on the ...

科研

生物工程

Observing and Quantifying Fibroblast-mediated Fibrin Gel Compaction

Cells embedded in collagen and fibrin gels attach and exert traction forces on the fibers of the gel. These forces can lead to local and global reorganization and realignment of the gel microstructure. This process proceeds in a complex manner that is dependent in part on the interplay between the location of the cells, the geometry of the gel, and the mechanical constraints on the gel. To better understand how these variables produce global fiber alignment patterns, we use time-lapse differential interference contrast (DIC) microscopy coupled with an environmentally controlled bioreactor to observe the compaction process between geometrically spaced explants (clusters of fibroblasts). The images are then analyzed with a custom image processing algorithm to obtain maps of the strain. The information obtained from this technique can be used to probe the mechanobiology of various cell-matrix interactions, which has important implications for understanding processes in wound healing, disease development, and tissue engineering applications.

Time-lapse microscopy and image processing techniques were used to observe and analyze fibroblast-mediated gel compaction and fibrin fiber realignment in an environmentally controlled bioreactor over a 48 hr&#160;period.

观察和量化纤维细胞介导的纤维素凝胶压实

Cells embedded in collagen and fibrin gels attach and exert traction forces on the fibers of the gel. These forces can lead to local and global ...

Full-field Strain Measurements for Microstructurally Small Fatigue Crack Propagation Using Digital Image Correlation Method

A novel measurement approach is used to reveal the cumulative deformation field at a sub-grain level and to study the influence of microstructure on the growth of microstructurally small fatigue cracks. The proposed strain field analysis methodology is based on the use of a unique pattering technique with a characteristic speckle size of approximately 10 &#181;m. The developed methodology is applied to study the small fatigue crack behavior in body centered cubic (bcc) Fe-Cr ferritic stainless steel with a relatively large grain size allowing a high spatial measurement accuracy at the sub-grain level. This methodology allows the measurement of small fatigue crack growth retardation events and associated intermittent shear strain localization zones ahead of the crack tip. In addition, this can be correlated with the grain orientation and size. Thus, the developed methodology can provide a deeper fundamental understanding of the small fatigue crack growth behavior, required for the development of robust theoretical models for the small fatigue crack&#160;propagation in polycrystalline materials.

Microstructurally small fatigue crack growth behavior is investigated using a novel methodological approach combining crack growth rate measurement and strain-field analysis to reveal the cumulative deformation field at sub-grain level.

基于数字图像相关的微结构小疲劳裂纹扩展的全场应变测量

A novel measurement approach is used to reveal the cumulative deformation field at a sub-grain level and to study the influence of microstructure on the ...

工程学

Intermediate Strain Rate Material Characterization with Digital Image Correlation

The mechanical response of a material under dynamic load is typically different than its behavior under static conditions; therefore, the common quasistatic equipment and procedures used for material characterization are not applicable for materials under dynamic loads. The dynamic response of a material depends on its deformation rate and is broadly categorized into high (i.e., greater than 200/s), intermediate (i.e., 10&#8722;200/s) and low strain rate regimes (i.e., below 10/s). Each of these regimes calls for specific facilities and testing protocols to ensure the reliability of the acquired data. Due to the limited access to high-speed servo-hydraulic facilities and validated testing protocols, there is a noticeable gap in the results at the intermediate strain rate. The current manuscript presents a validated protocol for the characterization of different materials at these intermediate strain rates. Strain gauge instrumentation and digital image correlation protocols are also included as complimentary modules to extract the utmost level of detailed data from every single test. Examples of raw data, obtained from a variety of materials and test setups (e.g., tensile and shear) is presented and the analysis procedure used to process the output data is described. Finally, the challenges of dynamic characterization using the current protocol, along with the limitations of the facility and methods of overcoming potential problems are discussed.

Here we present a methodology for the dynamic characterization of tensile specimens at intermediate strain rates using a high-speed servo-hydraulic load frame. Procedures for strain gauge instrumentation and analysis, as well as for digital image correlation strain measurements on the specimens, are also defined.

数字图像相关的中间应变率材料表征

The mechanical response of a material under dynamic load is typically different than its behavior under static conditions; therefore, the common ...

A Method to Estimate Cadaveric Femur Cortical Strains During Fracture Testing Using Digital Image Correlation

This protocol describes the method using digital image correlation to estimate cortical strain from high speed video images of the cadaveric femoral surface obtained from mechanical testing. This optical method requires a texture of many contrasting fiduciary marks on a solid white background for accurate tracking of surface deformation as loading is applied to the specimen. Immediately prior to testing, the surface of interest in the camera view is painted with a water-based white primer and allowed to dry for several minutes. Then, a black paint is speckled carefully over the white background with special consideration for the even size and shape of the droplets. Illumination is carefully designed and set such that there is optimal contrast of these marks while minimizing reflections through the use of filters. Images were obtained through high speed video capture at up to 12,000 frames/s. The key images prior to and including the fracture event are extracted and deformations are estimated between successive frames in carefully sized interrogation windows over a specified region of interest. These deformations are then used to compute surface strain temporally during the fracture test. The strain data is very useful for identifying fracture initiation within the femur, and for eventual validation of proximal femur fracture strength models derived from Quantitative Computed Tomography-based Finite Element Analysis (QCT/FEA).

In this protocol, the femur surface strains are estimated during fracture testing using the digital image correlation technique. The novelty of the method involves application of a high-contrast stochastic speckle pattern on the femur surface, carefully specified illumination, high speed video capture, and digital image correlation analysis for strain calculations.

基于数字图像相关的骨折检测中股骨皮质应变的估算方法

This protocol describes the method using digital image correlation to estimate cortical strain from high speed video images of the cadaveric femoral ...

Measuring Local Tissue Strains in Tendons via Open-Source Digital Image Correlation

There is considerable scientific interest in understanding the strains that tendon cells experience in situ and how these strains influence tissue remodeling. Based on this interest, several analytical techniques have been developed to measure local tissue strains within tendon explants during loading. However, in several cases, the accuracy and sensitivity of these techniques have not been reported, and none of the algorithms are publicly available. This has made it difficult for the more widespread measurement of local tissue strains in tendon explants. Therefore, the objective of this paper was to create a validated analysis tool for measuring local tissue strains in tendon explants that is readily available and easy to use. Specifically, a publicly available augmented-Lagrangian digital image correlation (ALDIC) algorithm was adapted for measuring 2D strains by tracking the displacements of cell nuclei within mouse Achilles tendons under uniaxial tension. Additionally, the accuracy of the calculated strains was validated by analyzing digitally transformed images, as well as by comparing the strains with values determined from an independent technique (i.e., photobleached lines). Finally, a technique was incorporated into the algorithm to reconstruct the reference image using the calculated displacement field, which can be used to assess the accuracy of the algorithm in the absence of known strain values or a secondary measurement technique. The algorithm is capable of measuring strains up to 0.1 with an accuracy of 0.00015. The technique for comparing a reconstructed reference image with the actual reference image successfully identified samples that had erroneous data and indicated that, in samples with good data, approximately 85% of the displacement field was accurate. Finally, the strains measured in mouse Achilles tendons were consistent with the prior literature. Therefore, this algorithm is a highly useful and adaptable tool for accurately measuring local tissue strains in tendons.

Measuring Local Tissue Strains in Tendons via Open-Source Digital Image Correlation

This paper describes an open-source digital image correlation algorithm for measuring local 2D tissue strains within tendon explants. The accuracy of the technique has been validated using multiple techniques, and it is available for public use.

通过开源数字图像相关 测量 肌腱中的局部组织应变

There is considerable scientific interest in understanding the strains that tendon cells experience in situ and how these strains influence tissue ...

Controlled Strain of 3D Hydrogels under Live Microscopy Imaging

External forces are an important factor in tissue formation, development, and maintenance. The effects of these forces are often studied using specialized in vitro stretching methods. Various available systems use 2D substrate-based stretchers, while the accessibility of 3D techniques to strain soft hydrogels, is more restricted. Here, we describe a method that allows external stretching of soft hydrogels from their circumference, using an elastic silicone strip as the sample carrier. The stretching system utilized in this protocol is constructed from 3D-printed parts and low-cost electronics, making it simple and easy to replicate in other labs. The experimental process begins with polymerizing thick (&#62;100 &#956;m) soft fibrin hydrogels (Elastic Modulus of ~100 Pa) in a cut-out at the center of a silicone strip. Silicone-gel constructs are then attached to the printed-stretching device and placed on the confocal microscope stage. Under live microscopy the stretching device is activated, and the gels are imaged at various stretch magnitudes. Image processing is then used to quantify the resulting gel deformations, demonstrating relatively homogenous strains and fiber alignment throughout the gel&#8217;s 3D thickness (Z-axis). Advantages of this method include the ability to strain extremely soft hydrogels in 3D while executing in situ microscopy, and the freedom to manipulate the geometry and size of the sample according to the user&#8217;s needs. Additionally, with proper adaptation, this method can be used to stretch other types of hydrogels (e.g., collagen, polyacrylamide or polyethylene glycol) and can allow for analysis of cells and tissue response to external forces under more biomimetic 3D conditions.

The presented method involves uniaxial stretching of 3D soft hydrogels embedded in silicone rubber while allowing live confocal microscopy. Characterization of the external and internal hydrogel strains as well as fiber alignment are demonstrated. The device and protocol developed can assess the response of cells to various strain regimes.

实时显微镜成像下的 3D 水凝胶控制应变

External forces are an important factor in tissue formation, development, and maintenance. The effects of these forces are often studied using specialized ...

A Method to Study the Correlation Between Local Collagen Structure and Mechanical Properties of Atherosclerotic Plaque Fibrous Tissue

The rupture of atherosclerotic plaques in coronary and carotid arteries is the primary cause of fatal cardiovascular events. However, the rupture mechanics of the heterogeneous, highly collagenous plaque tissue, and how this is related to the tissue's fibrous structure, are not known yet. Existing pipelines to study plaque mechanics are limited to obtaining only gross mechanical characteristics of the plaque tissue, based on the assumption of structural homogeneity of the tissue. However, fibrous plaque tissue is structurally heterogeneous, arguably mainly due to local variation in the collagen fiber architecture.
The mechano-imaging pipeline described here has been developed to study the heterogeneous structural and mechanical plaque properties. In this pipeline, the tissue's local collagen architecture is characterized using multiphoton microscopy (MPM) with second-harmonic generation (SHG), and the tissue's failure behavior is characterized under uniaxial tensile testing conditions using digital image correlation (DIC) analysis. This experimental pipeline enables correlation of the local predominant angle and dispersion of collagen fiber orientation, the rupture behavior, and the strain fingerprints of the fibrous plaque tissue. The obtained knowledge is key to better understand, predict, and prevent atherosclerotic plaque rupture events.

We have developed a mechano-imaging pipeline to study the heterogeneous structural and mechanical atherosclerotic plaque properties. This pipeline enables correlation of the local predominant angle and dispersion of collagen fiber orientation, the rupture behavior, and the strain fingerprints of the fibrous plaque tissue.

一种研究动脉粥样硬化斑块纤维组织局部胶原结构与力学性能相关性的方法

The rupture of atherosclerotic plaques in coronary and carotid arteries is the primary cause of fatal cardiovascular events. However, the rupture ...

A Novel Approach to Monitoring Graft Neovascularization in the Human Gingiva

Laser speckle contrast imaging (LSCI) is a novel method for measuring superficial blood perfusion over large areas. Since it is non-invasive and avoids direct contact with the measured area, it is suitable for monitoring blood flow changes during wound healing in human patients. Vestibuloplasty is periodontal surgery to the oral vestibule, aiming to restore vestibular depth with simultaneous enlargement of the keratinized gingiva. In this special clinical case, a split thickness flap was elevated at the first upper premolar and a xenogenic collagen matrix was adapted to the resulting recipient bed. LSCI was used to monitor the re- and neovascularization of the graft and the surrounding mucosa for one year. A protocol is introduced for the correct adjustment of microcirculation measurement in the oral mucosa, highlighting difficulties and possible failures.
The clinical case study presented demonstrated that &#8212; following the appropriate protocol &#8212; LSCI is a suitable and reliable method for following up microcirculation in a healing wound in the human oral mucosa and gives useful information on graft integration.

This study introduces a protocol for measuring microcirculation in human oral mucosa by laser speckle contrast imaging. The monitoring of wound healing after vestibuloplasty combined with a xenogenic collagen graft is presented on a clinical case.

一种监测人牙龈移植新生血管的新方法

Laser speckle contrast imaging (LSCI) is a novel method for measuring superficial blood perfusion over large areas. Since it is non-invasive and avoids ...

医学

Quantification of Vascular Parameters in Whole Mount Retinas of Mice with Non-Proliferative and Proliferative Retinopathies

Retinopathies are a heterogeneous group of diseases that affect the neurosensory tissue of the eye. They are characterized by neurodegeneration, gliosis&#160;and a progressive change in vascular function and structure. Although the onset of the retinopathies is characterized by subtle disturbances in visual perception, the modifications in the vascular plexus are the first signs detected by clinicians. The absence or presence of neovascularization determines whether the retinopathy is classified as either non-proliferative (NPDR) or proliferative (PDR). In this sense, several animal models tried to mimic specific vascular features of each stage to determine the underlying mechanisms involved in endothelium alterations, neuronal death and other events taking place in the retina. In this article, we will provide a complete description of the procedures required for the measurement of retinal vascular parameters in adults and early birth mice at postnatal day (P)17. We will detail the protocols to carry out retinal vascular staining with Isolectin GSA-IB4 in whole mounts for later microscopic visualization. Key steps for image processing with Image J Fiji software are also provided, therefore, the readers will be able to measure vessel density, diameter and tortuosity, vascular branching, as well as avascular and neovascular areas. These tools are highly helpful to evaluate and quantify vascular alterations in both non-proliferative and proliferative retinopathies.

This article describes a well-established and reproducible lectin stain assay for the whole mount retinal preparations and the protocols required for the quantitative measurement of vascular parameters frequently altered in proliferative and non-proliferative retinopathies.

利用数字图像相关表征的血管组织标本本地菌株

摘要

探索更多视频

此视频中的章节

在一个容器的支架部署在监测的墙力学

观察和量化纤维细胞介导的纤维素凝胶压实

基于数字图像相关的微结构小疲劳裂纹扩展的全场应变测量

数字图像相关的中间应变率材料表征

基于数字图像相关的骨折检测中股骨皮质应变的估算方法

通过开源数字图像相关测量肌腱中的局部组织应变

实时显微镜成像下的 3D 水凝胶控制应变

一种研究动脉粥样硬化斑块纤维组织局部胶原结构与力学性能相关性的方法

一种监测人牙龈移植新生血管的新方法

非增殖性和增殖性视网膜病变小鼠整个视网膜血管参数的定量

利用数字图像相关表征的血管组织标本本地菌株

摘要

探索更多视频

此视频中的章节

在一个容器的支架部署在监测的墙力学

观察和量化纤维细胞介导的纤维素凝胶压实

基于数字图像相关的微结构小疲劳裂纹扩展的全场应变测量

数字图像相关的中间应变率材料表征

基于数字图像相关的骨折检测中股骨皮质应变的估算方法

通过开源数字图像相关 测量 肌腱中的局部组织应变

实时显微镜成像下的 3D 水凝胶控制应变

一种研究动脉粥样硬化斑块纤维组织局部胶原结构与力学性能相关性的方法

一种监测人牙龈移植新生血管的新方法

非增殖性和增殖性视网膜病变小鼠整个视网膜血管参数的定量

通过开源数字图像相关测量肌腱中的局部组织应变