HIGH RESOLUTION BOLD VENOGRAPHIC IMAGING

高分辨率大胆静脉造影成像

• 批准号: 6286243
• 负责人: Ewart Mark Haacke
• 金额: $ 35.8万
• 依托单位: MRI INSTITUTE FOR BIOMEDICAL RESEARCH
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-16 至 2004-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6286243
• 关键词: bioimaging /biomedical imaging; blood volume; brain circulation; brain disorder diagnosis; brain imaging /visualization /scanning; clinical research; contrast media; diagnosis quality /standard; functional magnetic resonance imaging; hemodynamics; human subject; method development; neurophysiology; oxygen; oxygen transport; oxyhemoglobin; venography

DESCRIPTION (Verbatim from the Applicant's Abstract): A new venographic imaging method has been developed to probe brain function. The method relies on the changes induced in the MR signal in venous blood caused by the blood oxygenation level dependent (BOLD) effect from the presence of de-oxyhemoglobin. These changes cause a signal loss in the MR images due to the cancellation of venous blood with surrounding brain parenchyma. When this signal loss is examined as a function of echo time it reveals a unique signature, a non-exponential decay, indicative of the state of oxygen saturation and venous blood volume in the tissue. In this proposal, we plan to use a high resolution 3D version of this BOLD venographic (HRBV) method to cover a large region of interest in the brain. Specifically, we wish to understand the roles of intravascular and extravascular effects in causing this signal loss as a function of vessel size, oxygen saturation and field strength. Given this knowledge, we will attempt to predict both venous oxygen saturation and venous blood volume. This capability will be used under a number of physiologically challenged states in the brain using oxygen, and diamox. It is expected that a robust 3D methodology will be developed and validated to make this approach generally viable for clinical utility in the future. As part of this goal, we will revisit the quantification of oxygen saturation and blood volume measurements using a T1 reducing contrast agent. This will lead to higher quality images and improved accuracy and precision. Finally, we will test a new approach to functional brain imaging which offers the advantage of having a reduced sensitivity to field distortion and its associated signal loss when very long echo times are used. Today, refined techniques exist to handle many of the key experimental issues needed to accomplish these goals. The success of this research may offer a better means to evaluate brain function in fMRI experiments, to diagnose occult venous lesions, to study tumors and other vascular related diseases.

描述（逐字摘自申请人的摘要）：已经开发出一种新的静脉造影成像方法来探测脑功能。该方法依赖于 由血液引起的静脉血中MR信号的变化 存在的氧合水平依赖性（BOLD）效应 脱氧血红蛋白。这些变化会导致 MR 图像中的信号丢失，因为 静脉血与周围脑实质的取消。当这个 信号损失作为回波时间的函数进行检查，它揭示了一个独特的 特征，非指数衰减，指示氧的状态 组织中的饱和度和静脉血量。在本提案中，我们计划 使用这种 BOLD 静脉造影 (HRBV) 方法的高分辨率 3D 版本 覆盖大脑中一大片感兴趣的区域。具体来说，我们希望 了解血管内和血管外效应在导致这种情况中的作用 信号损失是血管尺寸、氧饱和度和场强的函数。 有了这些知识，我们将尝试预测静脉血氧饱和度 和静脉血量。此功能将在多种情况下使用 使用氧气和 Diamox 来调节大脑中的生理挑战状态。这是 预计将开发并验证强大的 3D 方法 这种方法在未来的临床应用中通常是可行的。作为一部分 为了这个目标，我们将重新审视血氧饱和度和血液的量化 使用 T1 还原造影剂进行体积测量。这将导致 更高质量的图像以及更高的准确性和精度。最后，我们将 测试一种新的功能性脑成像方法，该方法具有以下优点： 对场失真及其相关信号损失的敏感性降低 当使用很长的回波时间时。如今，已有先进的技术来处理 实现这些目标所需的许多关键实验问题。这 这项研究的成功可能为评估大脑功能提供更好的方法 功能磁共振成像实验，诊断隐匿性静脉病变，研究肿瘤和其他 血管相关疾病。