HIGHLY EFFICIENT CEREBRAL PERFUSION MRI

高效脑灌注 MRI

• 批准号: 9244859
• 负责人: David Alan Feinberg
• 金额: $ 68.83万
• 依托单位: ADVANCED MRI TECHNOLOGY, LLC
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2020-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9244859
• 关键词: Acceleration; Algorithms; Alzheimer' s Disease; Area; Arteriogram; Biological Markers; Blood; Blood capillaries; Bolus Infusion; Brain; Brain Diseases; Brain Neoplasms; Brain imaging; Brain scan; California; Cerebrovascular Circulation; Cerebrum; Characteristics; Clinical; Clinical Protocols; Clinical Research; Computer software; Data; Data Set; Degenerative Disorder; Diagnosis; Diagnostic; Diffusion; Disease; Evaluation; Family; Functional Imaging; Functional Magnetic Resonance Imaging; General Hospitals; Goals; Human; Image; Image Analysis; Imaging Techniques; Imaging technology; Injection of therapeutic agent; Label; Leukoencephalopathy; Magnetic Resonance Imaging; Manufacturer Name; Massachusetts; Measurement; Measures; Medical; Medical Research; Medical center; Methodology; Methods; Morphologic artifacts; Motion; Multiple Sclerosis; Neurodegenerative Disorders; Neurosciences Research; Noise; Parkinson Disease; Patients; Pennsylvania; Performance; Perfusion; Pharmacologic Substance; Pharmacotherapy; Phase; Physiologic pulse; Physiological; Predisposition; Process; Protocols documentation; Radiation; Research; Research Personnel; Resolution; San Francisco; Scanning; Scheme; Sensitivity and Specificity; Signal Transduction; Site; Slice; Speed; Spin Labels; Stroke; Sum; Techniques; Technology; Thick; Three-Dimensional Imaging; Time; Tissues; Tracer; Training; United States National Institutes of Health; Universities; age group; base; bioimaging; blood fractionation; blood perfusion; capillary; clinical Diagnosis; clinical imaging; connectome; contrast enhanced; design; hemodynamics; imaging approach; improved; innovation; medical schools; millisecond; nervous system disorder; neurovascular; new technology; normal aging; novel therapeutics; perfusion imaging; prevent; prototype; public health relevance; reconstruction; research clinical testing; time use; tool; tumor

DESCRIPTION (provided by applicant): MRI cerebral perfusion imaging is a widely disseminated technique on nearly all MRI scanners used for clinical diagnosis of brain disease and for neuroscience research. Over the last five years there has been considerably increased use of arterial spin labeling (ASL) for clinical diagnosis, while still i.v. injections of a gadoliium based contrast bolus are widely used clinically. Both brain perfusion methods, ASL and DSC techniques, involve making images very fast to identify the passage of blood through the capillary compartment. The image signal-to-noise ratio (SNR) is limited by the small (e.g., 3%) fraction of blood in tissue volumes. This is proportionately small but a second limitation is the time window of imaging, which is constrained to about 500-700 milliseconds for the capillary phase of blood passage. Therefore, rapid imaging of blood inflow is essential. For this reason DSC contrast based methods and ASL with multi-slice 2D EPI have not been able to satisfactorily image perfusion in the entire brain except with thick slices hence reduced spatial resolution. 3D imaging has therefore been developed as an alternative to 2D EPI. However, 2D images have certain desirable characteristics compared with 3D if there are patient motion artifacts. To overcome these limitations we propose to develop novel technology to acquire images simultaneously instead of separately. This approach called simultaneous multi-slice imaging ASL (SMS ASL) and SMS DSC increases by several fold the number of images that are acquired during the limited time window of capillary perfusion phase so the whole brain can be imaged. Another benefit of SMS-ASL is that the time to scan the brain can be greatly reduced by avoiding repeated scans of different brain areas, thus, reducing motion artifacts. A second major innovation in this project is the Hadamard encoded ASL, which is highly useful in clinical studies where the blood arterial transit time (ATT) is not known as in normal aging of people. The Hadamard-ASL acquires images at several different inflow times (TI) to be sure to capture the capillary perfusion phase of blood in at least one set of images. By acquiring the different TI values in a well-defined sub-bolus partitioning of the labeling period, their combination gives separated images at the distinct TI with essentially 2x the SNR and half the net scan time as required by current methodology which acquires each TI data set independently and sequentially. Both the Hadamard and the SMS can be combined for further improvements in SNR, speed and spatial resolution. This will highly impact the accessibility to patients and the robustness of the perfusion technology in clinical use. The availability of the new simultaneous perfusion imaging technology will give clinicians and researchers the capability of performing significantly improved MRI perfusion measurements in patients and these improvements will impact the diagnosis of many different brain diseases, including stroke, leukoencephalopathies and degenerative diseases; i.e., Alzheimer's disease and Parkinson's disease. Perfusion measurements of quantitative cerebral blood flow (CBF) and ATT are important quantitative biomarkers useful as physiological imaging in evaluating new drug therapies for brain diseases. This family of new perfusion imaging techniques utilizes more efficient pulse sequences that provide major advantages in resolution, slice coverage, SNR and speed. The new simultaneous imaging will have high utility and be highly desirable for use on clinical scanners worldwide. The improved quantitative MRI perfusion imaging offers overall increased efficiency that is highly commercializable given they provide improved diagnostic approaches to evaluate brain disease and further improve specificity and sensitivity in MRI neuroradiological exams. The new sequences will be designed, implemented and evaluated on MRI scanners operating at 1.5 Tesla at AMRIT, at 3T at University of California Berkeley and at 3T and 7T at University of California, San Francisco Medical Center and at Martinos Center for Biomedical Imaging, Massachusetts General Hospital, and Harvard Medical School. Once the new perfusion sequences are optimized they will be further evaluated and optimized in collaborative clinical test sites of UCSF Medical Center, UCLA and University of Pennsylvania. In addition to establishing their value in neuroradiology exams, they will be made into useful tools for basic and clinical neuroscience research.

描述（由申请人提供）：MRI脑灌注成像是几乎所有用于脑病临床诊断和神经科学研究的MRI扫描仪广泛传播的技术。在过去的五年中，对临床诊断的动脉自旋标记（ASL）的使用大大增加了，而仍在静脉注射。临床上广泛使用了基于Gadoliium的对比推注的注射。两种脑灌注方法，ASL和DSC技术都涉及使图像非常快地确定血液通过毛细管室的通道。图像信噪比（SNR）受组织体积中血液的小（例如3％）的限制。这是成比例小的，但第二个限制是成像的时间窗口，对于血液的毛细管阶段，该成像的时间窗口约为500-700毫秒。因此，血液流入的快速成像至关重要。因此，基于DSC对比度的方法和具有多型2D EPI的ASL无法在整个大脑中令人满意的图像灌注令人满意，除了切片较厚，因此空间分辨率降低。因此，已经开发出3D成像作为2D EPI的替代方法。但是，如果有患者运动伪像，则2D图像具有某些理想的特征。为了克服这些局限性，我们建议开发新技术以同时获得图像而不是单独获取图像。这种方法称为同时进行多切片成像ASL（SMS ASL）和SMS DSC的方法增加了几倍，比毛细血管灌注阶段的有限时间窗口中获得的图像数量增加，因此可以成像整个大脑。 SMS-ASL的另一个好处是，扫描大脑的时间可以通过避免反复对不同大脑区域的扫描来大大减少，从而减少了运动伪像。该项目中的第二个主要创新是Hadamard编码的ASL，在临床研究中非常有用，在临床研究中，血管过渡时间（ATT）在正常衰老中不被称为正常人。 Hadamard-ASL在几个不同的流入时间（Ti）中获取图像，以确保在至少一组图像中捕获血液的毛细血管灌注阶段。通过在标签周期的明确定义的子螺栓分区中获取不同的Ti值，它们的组合在不同的Ti上给出了分离的图像，基本上是2X，SNR和一半的净扫描时间按当前方法所需的一半，从而获得了每个TI数据集，从而独立和顺序地获得了每个TI数据集。 Hadamard和SMS都可以合并，以进一步改进SNR，速度和空间分辨率。这将极大地影响患者的可及性以及灌注技术在临床使用中的鲁棒性。新的同时灌注成像技术的可用性将使临床医生和研究人员在患者的MRI灌注测量中显着改善，这些改善将影响许多不同脑部疾病的诊断，包括中风，白血病术和退化性疾病；即阿尔茨海默氏病和帕金森氏病。定量脑血流（CBF）和ATT的灌注测量是重要的定量生物标志物，可作为生理成像，可用于评估用于脑疾病的新药物疗法。这种新的灌注成像技术家族利用了更有效的脉冲序列，这些脉冲序列在分辨率，切片覆盖率，SNR和速度方面具有主要优势。新的同时成像将具有很高的实用性，并且非常需要在全球临床扫描仪上使用。改进的定量MRI灌注成像提供了总体上提高的效率，鉴于它们提供了改进的诊断方法来评估脑部疾病并进一步提高MRI神经放射学检查的特异性和敏感性。新序列将在AMRIT的1.5 Tesla，加利福尼亚大学伯克利分校的3T和加利福尼亚大学，加利福尼亚大学，旧金山大学医疗中心以及马提尼斯生物医学成像中心的3T和7T上设计，实施和评估。一旦对新的灌注序列进行了优化，将在UCSF医学中心，加州大学洛杉矶分校和宾夕法尼亚大学的协作临床测试地点进行进一步评估和优化。除了建立其在神经放射学检查中的价值外，它们还将成为基础和临床神经科学研究的有用工具。