Depth-resolved optical imaging and microscopy of vascular compartment dynamics during somatosensory stimulation
Depth-resolved optical imaging and microscopy of vascular compartment dynamics during somatosensory stimulation
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DOI：
10.1016/j.neuroimage.2006.11.032
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发表时间：
2007-03-01
期刊：
影响因子：
5.7
通讯作者：
Boas, David A.
中科院分区：
文献类型：
--
作者：
Hillman, Elizabeth M. C.;Devor, Anna;Boas, David A.
使用深度分辨光学成像和体内双光子显微镜在单个血管室水平上研究了皮层对体感觉刺激的血流动力学反应。我们利用一种新的成像和时空分析方法，利用响应的动脉、小动脉、毛细血管和静脉的不同特征动态来隔离它们在皮层内的三维空间范围。这种空间描绘是用血管铸型验证的。时间描绘是由体内双光子显微镜的时间动力学和血管机制的动脉和静脉反应的支持。利用这些技术，我们已经能够表征不同的血管室在产生和控制体感觉刺激的血流动力学反应中的作用。我们发现小动脉总血红蛋白浓度的变化与小动脉扩张动力学非常一致，而小动脉扩张动力学又与静脉血流量的变化密切相关。对于4-s的刺激，我们只看到静脉血红蛋白浓度的微小变化，并且在静脉中没有检测到可测量的扩张或气球。相反，我们看到毛细血管充血的明显证据。我们将我们的发现与其他方式（包括功能磁共振成像）的复合血流动力学反应的历史观察结果进行比较。我们的结果的含义讨论了关于皮质血流动力学的数学模型，并对目前的理论机制的潜在神经血管耦合。我们还得出结论，我们的时空分析方法能够隔离和定位来自局部神经元激活的毛细血管床的信号，并有望提高其他血流动力学成像方式的特异性。(c) 2006爱思唯尔公司版权所有。
The cortical hemodynamic response to somatosensory stimulus is investigated at the level of individual vascular compartments using both depth-resolved optical imaging and in-vivo two-photon microscopy. We utilize a new imaging and spatiotemporal analysis approach that exploits the different characteristic dynamics of responding arteries, arterioles, capillaries and veins to isolate their three-dimensional spatial extent within the cortex. This spatial delineation is validated using vascular casts. Temporal delineation is supported by in-vivo two-photon microscopy of the temporal dynamics and vascular mechanisms of the arteriolar and venous responses.Using these techniques we have been able to characterize the roles of the different vascular compartments in generating and controlling the hemodynamic response to somatosensory stimulus. We find that changes in arteriolar total hemoglobin concentration agree well with arteriolar dilation dynamics, which in turn correspond closely with changes in venous blood flow. For 4-s stimuli, we see only small changes in venous hemoglobin concentration, and do not detect measurable dilation or ballooning in the veins. Instead, we see significant evidence of capillary hyperemia.We compare our findings to historical observations of the composite hemodynamic response from other modalities including functional magnetic resonance imaging. Implications of our results are discussed with respect to mathematical models of cortical hemodynamics, and to current theories on the mechanisms underlying neurovascular coupling. We also conclude that our spatiotemporal analysis approach is capable of isolating and localizing signals from the capillary bed local to neuronal activation, and holds promise for improving the specificity of other hemodynamic imaging modalities. (c) 2006 Elsevier Inc. All rights reserved.