Design and characterization of a microfabricated hydrogen clearance blood flow sensor.
Design and characterization of a microfabricated hydrogen clearance blood flow sensor.
复制标题
微制造氢清除率血流传感器的设计和表征。
DOI：
10.1016/j.jneumeth.2016.04.014
复制
发表时间：
2016
影响因子：
3
通讯作者：
Wightman,RMark
中科院分区：
文献类型：
--
作者：
Walton,LindsayR;Edwards,MartinA;McCarty,GregoryS;Wightman,RMark
背景现代脑血流量（CBF）检测倾向于使用限于大脑皮层区域的光学技术或昂贵的磁共振。几十年前，吸入气体清除率是定量CBF的首选方法，但其时间分辨率较差。电解H2清除（EHC）产生和收集气体原位在电极对，这提高了时间分辨率，但探针的大小已经禁止有意义的皮层下use.New methodWe微制造EHC电极的数量级小于现有的，在100 μm的规模，允许使用脑内深处。该设备提供了卓越的信噪比，在体外实现了高收集效率（40-50%），并与理论建模一致。体外化学反应模型用于确认我们的器械检测到的流速高于生理学预期。结合现实的噪声水平的计算建模表明，设备将是敏感的生理CBF rates.Comparison with existing methodThe减小尺寸的我们的阵列使他们适合皮层下的EHC测量，而不是较大的，现有的EHC电极，会造成实质性的组织损伤。我们的阵列每分钟可以收集多个CBF测量结果，因此可以在比现有气体清除测量更短的时间尺度上解决发生的生理变化。结论我们提出并表征了微加工EHC电极和随附的理论模型来解释获取的数据。微加工允许高通量生产可再现的设备，这些设备能够以亚分钟分辨率监测深部脑CBF。
BackgroundModern cerebral blood flow (CBF) detection favors the use of either optical technologies that are limited to cortical brain regions, or expensive magnetic resonance. Decades ago, inhalation gas clearance was the choice method of quantifying CBF, but this suffered from poor temporal resolution. Electrolytic H2clearance (EHC) generates and collects gas in situ at an electrode pair, which improves temporal resolution, but the probe size has prohibited meaningful subcortical use.New methodWe microfabricated EHC electrodes to an order of magnitude smaller than those existing, on the scale of 100 μm, to permit use deep within the brain.ResultsNovel EHC probes were fabricated. The devices offered exceptional signal-to-noise, achieved high collection efficiencies (40–50%) in vitro, and agreed with theoretical modeling. An in vitro chemical reaction model was used to confirm that our devices detected flow rates higher than those expected physiologically. Computational modeling that incorporated realistic noise levels demonstrated devices would be sensitive to physiological CBF rates.Comparison with existing methodThe reduced size of our arrays makes them suitable for subcortical EHC measurements, as opposed to the larger, existing EHC electrodes that would cause substantial tissue damage. Our array can collect multiple CBF measurements per minute, and can thus resolve physiological changes occurring on a shorter timescale than existing gas clearance measurements.ConclusionWe present and characterize microfabricated EHC electrodes and an accompanying theoretical model to interpret acquired data. Microfabrication allows for the high-throughput production of reproducible devices that are capable of monitoring deep brain CBF with sub-minute resolution.