Ultrasonic Instrumentation for Cardiovascular Studies

描述(逐字摘自申请者摘要)：总体目标 该项目是开发关于超声波仪器、换能器和 人体和动物模型心血管功能的评估技术 人类疾病。在过去的二十年里，已经发生了一个转变， 在医学研究中使用较小的动物，如大鼠和小鼠，因为 成本和近亲繁殖和基因工程模型的可用性。在这 更新提出了以下具体目标：1)发展多渠道， 高保真多普勒频谱分析仪和软件允许速度 在两个或多个部位同时测量小鼠的波形 足够的保真度以允许计算频谱以进行阻抗评估 以及涡度的探测和评估，以及亚毫秒级 评价心脏节律和动脉脉搏波的时间分辨率 速度。2)研制了一种简易的高空间分辨率M型超声心动图。 时间分辨率，并能够跟踪两个界面以进行生成 实时直径波形。该系统将与 现有的脉冲多普勒系统将提供动态的、时间相干的 测量信号以补充来自小鼠的速度、压力和心电信号。 3)发展小的、聚焦的、单元素的经胸和经食道 用于高分辨率多普勒和M型超声心动图的换能器 20 MHz在小鼠身上。这些将用于提高空间分辨率和(来自 食道入路)，以实现对主动脉和颈动脉的免提监测 速度和/或心脏大小。4)开发尾套压力测量系统 使用多普勒探头检测尾动脉血流的系统 在正常小鼠身上，舒张压可以无创地测量。5) 开发一种测量新鲜整体小样本(&lt；50 Ill)粘度的方法 血液利用多普勒检测自身产生的声流。6)申请 上述评估详细血流动力学的技术和系统 人类状况的小鼠模型，包括：动脉粥样硬化，心肌 缺血、心肌肥大、高血压、衰老、红细胞增多症等 心血管疾病。开发的方法将允许测量和 评估结果如何？心脏节律、血流速度、动脉脉搏波 血流速度、动脉阻抗谱、流体动力学、血液粘度；流量 扰动和涡度，压力-体积和压力-直径关系， 和外围电阻。其中一些非侵入性方法将是简单和 足够快的速度来筛选大量的转基因小鼠 心血管异常。

DESCRIPTION (Verbatim from Applicant's Abstract): The general goal of this project is to develop ultrason aboutc instrumentation, transducers, and techniques to evaluat about cardiovascular function in man and in animal models of human diseases. During the last two decades there has been a shift toward the use of smaller animals such as rats and mice in medical research because of cost and the availability of inbred and genetically engineered models. In this renewal the following specific aims are proposed: 1) Develop a multichannel, highfidelity Doppler spectrum analyzer and software to permit velocity waveforms to be measured at two or more sites simultaneously in mice with sufficient fidelity to allow calculations of spectra for impedance evaluation and the detection and evaluation of vorticity, and with sub-millisecond temporal resolution for evaluation of cardiac timing and arterial pulse wave velocity. 2) Develop a simple M-mode echocardiograph with high spatial and temporal resolution and with the ability to track two interfaces for generation of real-time diameter waveforms. The system would operate simultaneously with the existing pulsed Doppler system and would provide dynamic, time-coherent dimension signals to complement velocity, pressure, and ECG signals from mice. 3) Develop small, focussed, single-element transthoracic and transesophageal transducers for high-resolution Doppler and M-mode echocardiography at 10 and 20 MHz in mice. These would be used to improve spatial resolution and (from the esophageal approach) to permit hands-free monitoring of aortic and carotid velocity and/or cardiac dimensions. 4) Develop a tail-cuff pressure measurement system using a Doppler probe to sense tail artery flow so that both systolic and diastolic pressure could be measured noninvasively in intact mice. 5) Develop a method to measure viscosity in small (<50 Ill) samples of fresh whole blood using Doppler detection of self-generated acoustic streaming. 6) Apply the techniques and systems outlined above to evaluate detailed hemodynamics in murine models o human conditions including: atherosclerosis, myocardial ischemia, cardiac hypertrophy, hypertension, aging, polycythemia, and other cardiovascular disorders. The developed methods will allow measurement and evaluation oi? cardiac timing, blood flow velocity, arterial pulse wave velocity, arterial impedance spectra, fluid dynamies, blood viscosity;flow disturbances and vorticity, pressure-volume and pressure-diameter relations, and peripheral resistance. Some of these noninvasive methods will be simple and fast enough for screening large numbers of genetically-altered mice for cardiovascular abnormalities.