小梁响应压升高在活的人类眼睛
Summary
小梁网（TM）迁移进入施累姆氏管的空间可以由急性压力上升来诱导由ophthalmodynamometer，并通过谱域光学相干断层扫描观察。该方法的目标是要量化活流出道急性压力升高的在生物体组织的原位的形态反应。
Abstract
小梁网（TM）的机械特性都与流出阻力和眼内压（IOP）调节。这种技术背后的基本原理是直接观察以旧换新急性眼压升高的机械反应。在扫描之前，眼压测量在基线和在IOP升高。角膜缘是在基线和在高眼压扫描谱域光学相干断层扫描（ophthalmodynamometer（ODM）施加于30挤压力g）。扫描处理，以提高使用ImageJ房水外流通路的可视化。血管地标被用于识别在基线和高眼压扫描体积相对应的位置。 Schlemm管（SC）的截面积（SC-CSA）和由前向沿其长轴后路SC长度手动在SC的1毫米段内10个位置测量。平均数内到外壁上的距离（短轴长度）计算为SC的由划分区域其长轴长度。为了检查邻近组织的效果的IOP升高的贡献，重复测量不具有和具有平滑肌松弛与托滴注。 TM迁移进入SC由TM刚度抵抗，但由它附着到相邻的平滑肌睫状体内的支持增强。这种技术是在第一测量生理条件下，人眼内的活的人类TM响应于压力上升的原位 。
Introduction
青光眼是全球第二大不可逆转的失明1的原因。升高的眼内压（IOP）是用于青光眼2-7的存在和发展的主要致病危险因素。 眼压是由房水8的形成和流出之间的平衡调节。最大流出阻力的位置是juxtacanicular组织和Schlemm管（SC）的内壁，SC和小梁网（TM）9-11之间的接口。而TM刚度可以在IOP升高的脸向预防SC崩溃，奥弗等人 12最近证明在青光眼基因表达被改变，从而提高SC内皮变硬，妨碍形成气孔，导致高眼压中青光眼13。 TM形态和刚度与相关设施的流出14,15，强调牛逼他需要测量其生物力学特性。
以旧换新的原子力显微镜测量表明高架刚度眼青光眼患者（81千帕）捐赠的眼睛捐助者无青光眼（4.0千帕）16相比，但这些测量是在解剖离体组织进行。后TM被锚定到经由纵肌细胞中插入到外lamellated和cribiform TM 17的前肌腱睫状肌。睫状肌（CM）的活动可能会增加TM绷紧，酷似TM升高17的刚度。观察改建耐诱导的平滑肌扰动SC崩溃的能力已经显示出在动物模型18。我们已经证明了能够非侵入性图像的主房水外流系统在活的人的眼睛的远端并包括SC使用谱域光学相干断层扫描（OCT）<SUP> 19-21。使用这种技术，我们已经证明，量化TM和SC急性IOP升高22的形态反应的能力。
本文所描述的方法的总体目标是量化活流出道急性IOP升高的在生物体组织中原位形态响应。这种技术具有检查在生理条件下对TM，其中既包括收缩纤维活性的T M和CM以TM刚度内贡献相比，在解剖组织制成公布的测量的优点。背后采用这种技术来观察机械TM响应的理由是，它为我们提供了其他原因无法分析上市公司以旧换新，我们现在知道被直接链接到水流出阻力，眼压第13条的力学性能。辨别收缩组织对整体刚度，小的银的贡献受试者室温进行了检查，并没有与抑制平滑肌的活动由托的管理。
Protocol
Representative Results
Discussion
本技术利用非侵入性的观察软组织的机械响应量化的SC崩溃。利用人类尸体的眼睛今后的工作中，需要解剖后校准组织变形实际组织硬度。但是，这样的研究将遭受先前流出模型的相同的限制;具体地，该活肌到组织张力的贡献将不存在。在哺乳动物活眼模型进一步校准可以让影像和TM的刚度直接测量校准。
有几个限制的技术。它尚待证实在其他平台华侨城。该文献表明，相同…
Divulgazioni
The authors have nothing to disclose.
Acknowledgements
Supported in part by National Institute of Health contracts R01-EY13178, and P30-EY08098 (Bethesda, MD), the Eye and Ear Foundation (Pittsburgh, PA), and unrestricted grants from Research to Prevent Blindness (New York, NY).
Materials
| Spectral Domain OCT | Zeiss | Cirrus | |
| Imaging Workstation | Apple | iMac | |
| Ophthalmodynamometer | (Baillairt Matalene Ophthalmodynamometer, Surgical instruments CO., Inc. New York, NY) | ||
| Image Processing Program | rsb.info.nih.gov/ij | ImageJ, FIJI | |
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