Development of Novel Methods for Tissue Characterization in the Heart with Ultrasound Imaging

超声成像心脏组织定征新方法的研究进展 背景：超声成像因其相对低的成本、安全性(无电离辐射X射线)、便携和快速的采集速度而成为使用最广泛的医学成像方式之一(全球数以万计的临床和研究机器)。心脏超声成像(超声心动图)通常用于测量心脏的结构和功能、血流和心脏的其他几个属性(最常用于心脏病诊断的临床成像测试)。然而，超声心动图(超声应用于心脏)目前不能用于检测心脏中的疤痕(纤维化)。 动机：当心肌受损(如心脏病发作)时，部分肌肉死亡，形成一种保护性疤痕，称为替代性纤维化，由胶原等结构分子组成。心脏病的准确诊断和最佳治疗处方需要关于心脏疤痕(纤维化)形成的信息。目前，磁共振成像(MRI)是检测纤维化的金标准。然而，核磁共振相对昂贵，在主要医院中心之外无法获得，排除了许多患者(例如许多植入设备的患者、重症监护环境中的患者、肥胖患者)，并且需要注射造影剂来检测纤维化。拟议的计划将以超声成像的发展为中心，以允许对瘢痕(纤维化)进行成像。 方法：我们将使用一种名为谐波超声的特殊超声成像模式来实现我们的目标。谐声波是从具有一定材料特性的结构中产生的。心脏病中形成的疤痕组织主要由胶原蛋白和其他分子组成，这些分子会产生非常强烈的谐波声波。通过优化超声成像以提供来自胶原蛋白的最大谐波信号，我们希望能够生成心脏疤痕组织的清晰图像。 影响：心脏疤痕的新超声心动图测试的开发将立即影响超声成像领域以及成千上万的加拿大人。我们预计，我们提出的技术创新将推进心脏和所有其他组织的超声成像领域。对于加拿大人来说，我们预计，对加拿大最常见的心脏病(心脏病发作)进行更快、更便宜、更广泛的检测将有助于改善医疗保健的提供。最好的治疗(基于准确的诊断)在最初的事件发生后尽快应用将产生最高的影响。通过向心脏病学中最广泛使用的成像工具(超声心动图)提供SCAR成像，我们希望每天使用超声波改善大型医疗中心和较小卫星中心的一线医疗保健。

Development of Novel Methods for Tissue Characterization in the Heart with Ultrasound Imaging BACKGROUND: Ultrasound imaging is one of the most widely used medical imaging modalities (tens of thousands of clinical and research machines worldwide) as a result of its relatively low cost, safety (no ionizing radiation - X-Rays), portability and rapid acquisition speeds. Ultrasound imaging in heart disease (Echocardiography) is routinely used to measure heart structure and function, blood flow, and several other properties of the heart (most used clinical imaging test for diagnosis of heart disease). However, Echocardiography (ultrasound applied to the heart) is not currently used to detect scar (fibrosis) in heart. MOTIVATION: When the heart muscle is damaged (e.g. heart attack), part of the muscle dies and a protective scar forms, called replacement fibrosis, which is composed of structural molecules such as collagen. The accurate diagnoses of heart disease and optimal prescription of therapy requires information about the formation of scar (fibrosis) in the heart. Currently, magnetic resonance imaging (MRI) is the gold standard test for the detection of fibrosis. However, MRI is relatively expensive, not available outside major hospital centres, excludes many patients (e.g. many with implanted devices, those in critical care environments, obese patients) and requires an injected contrast agent injection to detect fibrosis. The proposed program will center on the development of ultrasound imaging to allow the imaging of scar (fibrosis). METHODS: We will achieve our goals using a special mode of ultrasound imaging called harmonic ultrasound. Harmonic sound waves are generated from structures that have certain material properties. The scar tissue that forms in heart disease is made primarily of collagen and other molecules that generate very strong harmonic sound waves. By optimizing ultrasound imaging to give the maximum harmonic signal from collagen, we expect to be able to generate clear images of scar tissue in the heart. IMPACT: The development of new echocardiography tests for scar in the heart will immediately impact the field of ultrasound imaging as well as thousands of Canadians. We expect our proposed technical innovations will advance the field of ultrasound imaging, in the heart and all other tissues. For Canadians, we anticipate that a faster, cheaper and more widely available test for the most common heart disease in Canada (heart attack) will lead to improved delivery of health care. The best therapy (based on accurate diagnosis) applied as soon as possible after the initial event will have the highest impact. By providing imaging of scar to the most widely available imaging tool in cardiology (Echocardiography) we hope to improve frontline medical care in both large medical centres and the smaller satellite centres using ultrasound on a daily basis.