Harmonic Doppler Ultrasound Embolus Characterization

谐波多普勒超声栓塞表征

• 批准号: 7027750
• 负责人: Mark A Moehring
• 金额: $ 26.12万
• 依托单位: SPENCER TECHNOLOGIES
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-03-07 至 2008-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7027750
• 关键词: adult human (21+); bioimaging /biomedical imaging; biomedical equipment development; cerebral artery; cerebrovascular imaging /visualization; clinical research; computer program /software; diagnosis design /evaluation; embolism; female; human subject; laboratory rabbit; phantom model; physical process; ultrasound blood flow measurement

DESCRIPTION (provided by applicant): This proposal is to develop a power M-mode Doppler ultrasound device for monitoring blood flow in the basal arteries of the brain for embolic events, and characterizing these emboli as gas bubbles or particulates. This device is of significant value in several venues where medical procedures result in emboli going to the brain. Substantial clinical significance of embolus characterization is found in surgeries utilizing cardiopulmonary bypass, for which numerous outcomes studies have documented short and long term cognitive decline. Approximately one third of strokes associated with CPB are intra operative[l], a majority of which are embolic. The effects of embolization are currently not appreciated until the patient comes out of anesthesia and manifests neurologic deficits in the intensive care unit, which is too late to take preventive or therapeutic action. Ultrasound differentiation of embolus composition during surgery is therefore of great value for appropriately responding to the type of emboliziation with therapy or modification in surgical approach or technique. This proposal is based on successful in vitro (flow phantom) and in vivo (characterization of emboli from prosthetic heart valves in a human subject) feasibility experiments for Doppler ultrasound discrimination of gas bubbles and particulates. The critical elements for this technology are: (1) a high dynamic range Doppler ultrasound platform capable of processing Doppler shifts from fundamental and second harmonic reflections from moving scatterers and (2) a transducer with similar sensitivity patterns at both fundamental and second harmonic frequencies. The proposed work is to further develop these critical elements by refinement of probe design, enhancement of signal processing of the fundamental and second harmonic echoes from emboli, and presentation of the characterization results to the operator in an easily appreciated image format. The system developed in this proposal will be tested in a series of experiments on a flow loop, an animal model of the human middle cerebral artery, and on human subjects undergoing Tran cranial Doppler evaluation for presence and severity of patent foramen ovale. These tests will include observation of single emboli and embolus showers, with variable embolus size and composition. This work is anticipated to result in improved neurological outcomes in the targeted heart surgery application, and a Phase III partner is ready and waiting to take the technology to market.

描述（由申请人提供）： 该建议是开发一个功率M模式多普勒超声设备，以监测大脑基础动脉中的血流以进行栓塞事件，并将这些栓塞表征为气泡或颗粒。在医疗程序导致Emboli进入大脑的几个场所中，该设备具有显着价值。在使用心肺旁路的手术中发现了栓塞表征的实质性临床意义，为此，许多结果研究记录了短期和长期认知能力下降。与CPB相关的中风中约有三分之一是手术室内[L]，其中大多数是栓塞。直到患者摆脱麻醉并表现出重症监护病房的神经系统缺陷，目前才能得到栓塞的影响，这为时已晚，无法采取预防或治疗作用。因此，在手术过程中，栓塞组成的超声分化对于适当响应手术方法或技术中的治疗或修饰的栓塞类型具有巨大的价值。该建议基于成功的体外（流动幻影）和体内（人类受试者中假体心脏瓣膜的栓塞表征）的可行性实验，用于多普勒对气泡和微粒的多普勒超声区分。该技术的关键要素是：（1）一个高动态范围多普勒超声平台，能够处理多普勒从移动散射器的基本和第二个谐波反射转移，并且（2）在基本和第二谐波频率下具有相似灵敏度模式的传感器。拟议的工作是通过细化探针设计，增强栓塞的基本和第二谐波回声的信号处理，并以易于欣赏的图像格式向操作员表现出来。该提案中开发的系统将在一系列有关流动环，人类中大脑动脉的动物模型以及接受tran颅颅多普勒评估的人类受试者中进行测试。这些测试将包括观察单个栓子和栓子淋浴，并具有可变的栓子大小和组成。预计这项工作将在靶向心脏手术应用中改善神经系统效果，并且III期合作伙伴已经准备好并等待将技术推向市场。