Analyses of gradient echo MRI data

梯度回波 MRI 数据分析

• 批准号: 8098408
• 负责人: Yi Wang
• 金额: $ 39.45万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-04-15 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8098408
• 关键词: Acute; Algorithms; Blood; Calibration; Cerebral hemisphere hemorrhage; Data; Data Analyses; Development; Diagnosis; Diffusion Magnetic Resonance Imaging; Disease; Drug Formulations; Equation; Ferritin; Foundations; Functional Magnetic Resonance Imaging; Growth; Hematoma; Hemorrhage; Hemosiderin; Image; Imagery; In Vitro; Iron; Link; Magnetic Resonance Imaging; Maps; Measurement; Measures; Methemoglobin; Methods; Morbidity - disease rate; Morphologic artifacts; Morphology; Neurodegenerative Disorders; Patients; Phase; Predisposition; Property; Research; Severities; Signal Transduction; Solutions; Source; Structure; Testing; Tissue Extracts; Tissues; Traumatic Brain Injury; Validation; Vascular Diseases; Weight; acute stroke; base; blood product; clinical practice; deoxyhemoglobin; in vivo; magnetic field; method development; mortality; novel; object shape; simulation

DESCRIPTION (provided by applicant): The objective of this research is to develop novel analyses of the gradient echo (GRE) MRI data for quantitative characterization of intrinsic tissue property. Gradient echo MRI has been routinely used in clinical practice. A major aspect of its image contrast is based on its unique signal sensitivity to tissue susceptibility, which is particularly useful for studying blood deoxyhemoglobin (foundation of fMRI) and blood breakdown products, methemoglobin, hemosiderin and ferritin (various bleeding disorders including traumatic brain injury, hemorrhage and microbleed, vascular disorders, neurodegenerative diseases, et al) that have strong susceptibilities. For example, GRE MRI is becoming a method replacing CT for measuring acute intracerebral hemorrhage (ICH). However, GRE MRI is well known to have blooming susceptibility artifacts that make it difficult to identify the true boundary of hematoma and overestimate hematoma volume, a critical parameter in managing ICH patients. We hypothesize that rigorous analysis of GRE MRI data can allow accurate mapping of susceptibility source, enabling robust identification of hematoma volume. Mapping tissue susceptibility requires solving the field-to-source inverse problem, which is ill-posed using the phase data alone. We propose to develop a novel morphology enabled dipole inversion (MEDI) approach for analyzing both phase and magnitude data gradient echo MRI to extract tissue susceptibility quantity. The phase image contains the magnetic field information for fitting susceptibility via Maxwell's Equation. The magnitude image contains tissue structure information for matching with susceptibility interfaces via least discordance. We have proved mathematically that these phase and magnitude information are sufficient to determine susceptibility. We have obtained very encouraging preliminary data indicating that our MEDI inverse approach is sufficiently accurate in solving the field to source inverse problem. Accordingly, our proposed research consists of the following specific aims. 1) Develop the MEDI approach for analyzing phase and magnitude data in gradient echo MRI. 2) Apply MEDI to analyze gradient echo MRI of patients with primary ICH for measuring hematoma by comparing with CT. PUBLIC HEALTH RELEVANCE: This proposed research will develop novel analyses of gradient echo MRI data for characterizing tissue intrinsic susceptibility property. Successful development of this susceptibility mapping will allow accurate identification of hemorrhage border, solving a major problem of hematoma volume measurement in gradient echo MRI of intracerebral hemorrhage.

描述（由申请人提供）：本研究的目的是对梯度回波（GRE）MRI 数据进行新颖的分析，以定量表征内在组织特性。梯度回波 MRI 已常规用于临床实践。其图像对比度的一个主要方面是基于其对组织敏感性的独特信号敏感性，这对于研究血液脱氧血红蛋白（功能磁共振成像的基础）和血液分解产物、高铁血红蛋白、含铁血黄素和铁蛋白（各种出血性疾病，包括创伤性脑损伤、出血和微出血、血管疾病、神经退行性疾病等）具有很强的敏感性。例如，GRE MRI 正在成为替代 CT 测量急性脑出血 (ICH) 的方法。然而，众所周知，GRE MRI 具有光晕敏感性伪影，导致难以识别血肿的真实边界并高估血肿体积，而血肿体积是治疗 ICH 患者的关键参数。 我们假设对 GRE MRI 数据的严格分析可以准确绘制磁敏感源，从而能够可靠地识别血肿体积。绘制组织磁化率需要解决场到源逆问题，仅使用相位数据是不适定的。我们建议开发一种新型形态学偶极子反演（MEDI）方法，用于分析相位和幅度数据梯度回波 MRI，以提取组织磁化率量。相位图像包含用于通过麦克斯韦方程拟合磁化率的磁场信息。幅度图像包含用于通过最小不一致与磁化率界面进行匹配的组织结构信息。我们已经在数学上证明这些相位和幅度信息足以确定磁化率。我们已经获得了非常令人鼓舞的初步数据，表明我们的 MEDI 逆方法在解决场源逆问题时足够准确。因此，我们提出的研究包括以下具体目标。 1) 开发 MEDI 方法来分析梯度回波 MRI 中的相位和幅度数据。 2)应用MEDI分析原发性ICH患者的梯度回波MRI以测量血肿，并与CT进行比较。 公共健康相关性：这项拟议的研究将对梯度回波 MRI 数据进行新颖的分析，以表征组织内在的敏感性特性。这种磁敏感图的成功开发将能够准确识别出血边界，解决脑出血梯度回波MRI中血肿体积测量的主要问题。