Rapid MRI Measures of Absolute Fat Mass in Adipose Tissue and Organs

脂肪组织和器官中绝对脂肪量的快速 MRI 测量

• 批准号: 7590632
• 负责人: Krishna S Nayak
• 金额: $ 20.38万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-02-01 至 2010-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7590632
• 关键词: Abdomen; Abdominal Cavity; Adipose tissue; Adolescent; Adult; Affect; American; Animal Experimentation; Animal Model; Animal Testing; Animals; Area; Autopsy; Back; Body Composition; Body fat; Calibration; Cardiovascular Diseases; Cardiovascular system; Central obesity; Chemicals; Child; Clinical; Data; Development; Diabetes Mellitus; Disease; Environment; Epidemic; Evaluation; Family suidae; Farming environment; Fatty Liver; Fatty acid glycerol esters; Glucose; Goals; Gold; Health; Heart Diseases; Hour; Human; Hyperlipidemia; Image; Imaging Techniques; Infiltration; Insulin Resistance; Intervention; Ionizing radiation; Link; Liver; Liver diseases; Location; Magnetic Resonance Imaging; Magnetism; Measurement; Measures; Metabolic; Methods; Metric; Modality; Modeling; Motion; Muscle; Non-Insulin-Dependent Diabetes Mellitus; Obesity; Organ; Outcome; Pancreas; Patients; Procedures; Protocols documentation; Protons; Relative (related person); Research; Research Infrastructure; Research Personnel; Research Support; Resolution; Risk; Risk Assessment; Scanning; Scheme; Signal Transduction; Skeletal Muscle; Techniques; Testing; Time; Tissues; Translational Research; United States; Validation; Variant; Visceral; Water; base; cost; density; imaging modality; improved; in vivo; innovation; interest; novel; novel therapeutic intervention; public health relevance; rapid technique; subcutaneous; tool

DESCRIPTION (provided by applicant): Obesity is a growing epidemic in the United States, affecting multiple health outcomes in children, adolescents, and adults. Increasing data suggest that the link between obesity and poor health outcome is related to buildup of fat in specific areas (e.g. visceral fat inside the abdominal cavity) and/or infiltration of fat into the liver, pancreas, and other organs. Quantification of visceral fat and organ fat in vivo is generally performed by magnetic resonance imaging (MRI). MRI is well suited for this purpose because it is inherently three-dimensional, provides a sensitive mechanism for separating water and fat, and involves no ionizing radiation, leading to indefinite repeatability with ultra-low risk. Although MRI is becoming more frequently used in obesity research, its ability to directly quantify fat mass has not yet been developed and validated. Current measurements are either relative (e.g. fat signal fraction) or indirect (e.g. adipose tissue volume). Moreover, current MRI protocols are limited by the high-cost of magnet time, and the long and/or multiple breath-holds that are uncomfortable and reduce accuracy. The objective of this proposal is to overcome these limitations and develop and fully validate a novel MRI-based method for the rapid quantification of fat mass throughout the abdomen. Specifically, we will (1) develop signal calibration procedures that allow for the quantification of fat mass on a voxel-by-voxel basis, and (2) evaluate the accuracy of this quantification in swine, by comparing measurements of fat mass in adipose tissue, whole organs, and muscle, with post-mortem chemical analysis (the current gold standard). The SIGNIFICANCE of this proposal lies in the development of a new, promising, and potentially cost-effective tool for assessing fat mass and organ fat infiltration. The APPROACH utilizes recent advances in rapid MRI fat-water separation, calibration scans, and rigorous validation in an animal model. The INNOVATION lies in the application of novel signal models and calibration schemes for quantifying fat mass from signal intensity. The INVESTIGATORS include two MR physicists with expertise in the development of rapid MRI techniques for cardiovascular disease assessment and an established obesity researcher with expertise in the validation of body composition techniques. The ENVIRONMENT at USC provides generous access to research- dedicated imaging facilities, animal research support, and infrastructure for this translational research. PUBLIC HEALTH RELEVANCE: Abdominal obesity is a growing problem among Americans, and is linked with increased risks of fatty liver disease, heart disease, and type-2 diabetes, among other things. This proposal will develop a new non-invasive test based on magnetic resonance imaging that determines the mass and location of fat within the abdomen, including critical organs, and may potentially be a useful tool in obesity research.

描述（由申请人提供）：肥胖在美国是一种日益严重的流行病，影响儿童、青少年和成人的多种健康结果。越来越多的数据表明，肥胖与不良健康结果之间的联系与特定区域的脂肪堆积（例如腹腔内的内脏脂肪）和/或脂肪渗透到肝脏、胰腺和其他器官有关。体内内脏脂肪和器官脂肪的定量通常通过磁共振成像（MRI）进行。 MRI 非常适合此目的，因为它本质上是三维的，提供了分离水和脂肪的敏感机制，并且不涉及电离辐射，从而导致无限重复性和超低风险。尽管 MRI 在肥胖研究中的应用越来越频繁，但其直接量化脂肪量的能力尚未得到开发和验证。当前测量是相对的（例如脂肪信号分数）或间接的（例如脂肪组织体积）。此外，当前的 MRI 方案受到磁体时间成本高、长时间和/或多次屏气的限制，这些屏气会让人不舒服并降低准确性。该提案的目的是克服这些限制，开发并充分验证一种基于 MRI 的新型方法，用于快速量化整个腹部的脂肪量。具体来说，我们将（1）开发信号校准程序，允许在逐个体素的基础上量化脂肪量，以及（2）通过比较脂肪组织中脂肪量的测量值来评估猪的这种量化的准确性、整个器官和肌肉，进行尸检化学分析（当前的金标准）。该提案的意义在于开发一种新的、有前途的、具有潜在成本效益的工具来评估脂肪量和器官脂肪浸润。该方法利用了快速 MRI 脂水分离、校准扫描和动物模型严格验证方面的最新进展。创新在于应用新颖的信号模型和校准方案来根据信号强度量化脂肪量。调查人员包括两名在开发用于心血管疾病评估的快速 MRI 技术方面具有专业知识的 MR 物理学家，以及一名在验证身体成分技术方面具有专业知识的肥胖研究人员。南加州大学的环境为研究专用成像设施、动物研究支持和转化研究的基础设施提供了慷慨的机会。公共健康相关性：腹部肥胖是美国人中一个日益严重的问题，并且与脂肪肝、心脏病和 2 型糖尿病等疾病的风险增加有关。该提案将开发一种基于磁共振成像的新型非侵入性测试，可确定腹部（包括关键器官）内脂肪的质量和位置，并可能成为肥胖研究的有用工具。