Technology for Portable MRI

便携式 MRI 技术

• 批准号: 9346073
• 负责人: Lawrence L Wald
• 金额: $ 60.82万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-01 至 2020-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9346073
• 关键词: Accident and Emergency department; Acute; Address; Ambulances; Area; Beds; Birds; Brain; Brain Diseases; Brain Injuries; Brain hemorrhage; Brain imaging; Caliber; Caring; Clinic; Clinical; Clinical assessments; Consumption; Critical Illness; Data; Detection; Development; Devices; Diagnosis; Diagnostic; Dimensions; Disease; Emergency Medicine; Emergency Situation; Goals; Head; Helmet; Hematoma; Hemorrhage; Hospitals; Human; Image; Intensive Care Units; Lesion; Location; Magnetic Resonance Imaging; Maintenance; Methods; Military Personnel; Modeling; Monitor; Nature; Nervous System Trauma; Neurologic; Neurology; Operative Surgical Procedures; Pathology; Patients; Pattern; Performance; Perioperative; Phase; Procedures; Protons; Rotation; Rural; Schools; Signal Transduction; Site; Source; Sports; Stents; System; Technology; Testing; Three-Dimensional Imaging; Time; Ultrasonography; Weight; Work; X-Ray Computed Tomography; cohort; cost; cryogenics; density; design; design and construction; diagnostic accuracy; experimental study; image reconstruction; imaging system; improved; instrument; killings; light weight; magnetic field; miniaturize; nervous system disorder; neuro-oncology; neurosurgery; novel; novel strategies; point of care; portability; pre-clinical trial; prototype; public health relevance; reconstruction; research clinical testing; rural healthcare; simulation; standard of care

DESCRIPTION (provided by applicant): Magnetic Resonance Imaging (MRI) has been the undisputed standard of care for the detection and diagnosis of neurological disorders and injuries since its inception over 3 decades ago. The cost, weight, size, and maintenance needs of MRI scanners, however, typically precludes their use in some locations with perhaps the greatest need - including Emergency Departments, Neurological Intensive Care Units (ICUs), surgical suites, sports fields, battlefields, rural healthcare sites, and ambulances. Indeed, no truly portable, "point-of-care" MRI system currently exists, despite attempts by several groups to miniaturize and simplify MRI scanner components. A new approach is needed to create such a truly portable, affordable brain scanner, referred to here as the "Portable Brain Scanner" (PBS). The problem, however, with rendering conventional scanners portable is not only the requirement for a large, highly homogeneous magnetic field (necessitating the use of multi ton magnets and cryogenic apparatus), but also, the weight and power consumption requirements of switchable gradient encoding fields (an additional ton of weight and up to 2 MW of peak power). In this work, we refine our proof-of-concept prototype PBS and, in pilot clinical testing, validate it as a low cost, point-of-care MRI scanner that can be sited almost anywhere. We employ an approach whereby the magnet's field homogeneity requirements are relaxed approximately 1000 fold. This allows a lightweight, permanent magnet design with no cryogens or power consumption. Our prototype brain magnet weighs just 45kg. We achieve image encoding and eliminate the heavy, power consuming gradient coil, by rotating this inhomogeneous field around the head using the magnet's field inhomogeneity to spatially modulate the signal in a generalized fashion compared to what is done with conventional imaging gradients. Specifically, the field inhomogeneities of the main magnet serve as the encoding field, and the image is reconstructed as an iterative inverse problem. This design "kills two birds with one stone", in that it both simplifies the magnet and eliminates the gradient coil - resulting in a truly "point-of-care" brain MRI scanner. We further refine this design by adding truly parallel reception, to improve spatial encoding, as well as by adding TRASE encoding for the third dimension. Preliminary clinical evaluation of this prototype will be performed on a cohort of patients with mild-to-moderate hemorrhagic brain injury in the Emergency Department, and in stable peri-operative patients with structural lesions in the Neurological Intensive Care Unit.

描述（由申请人提供）：磁共振成像（MRI）是自3年前成立以来神经系统疾病和伤害的检测和诊断的无可争议的护理标准。然而，MRI扫描仪的成本，重量，大小和维护需求通常排除在某些地方的使用，也许最大的需求 - 包括急诊部门，神经系统重症监护病房（ICU），外科手术套房，运动场，战场，战场，农村医疗保健场所和救护车。的确，尽管有几个小组试图微型化和简化MRI扫描仪组件，但目前尚无真正便携式的“现有” MRI系统。需要一种新的方法来创建这种真正的便携式，负担得起的脑扫描仪，并在此称为“便携式脑扫描仪”（PBS）。但是，由于渲染传统的扫描仪便携式，问题不仅是对高度均匀的磁场（需要使用多吨磁铁和低温设备）的要求，而且还需要切换梯度编码场的重量和功率消耗（额外的重量和高达2 MW的峰值电源））。在这项工作中，我们完善了概念验证原型PBS，在试点临床测试中，将其验证为低成本，即护理点MRI扫描仪，几乎可以在任何地方放置。我们采用一种方法，从而使磁铁的场均匀性要求放松约1000倍。这允许轻巧，永久性的磁铁设计，没有冷冻剂或功耗。我们的原型脑磁铁仅重45公斤。我们通过使用磁铁场不均匀旋转此不均匀的磁场来实现图像编码并消除了沉重的，消耗的梯度线圈，与传统成像梯度相比，以广义方式调节了信号的空间调节信号。具体而言，主磁体的字段不均匀性用作编码场，并将图像重建为迭代反问题。这种设计“用一块石头杀死两只鸟”，因为它既简化了磁铁，又消除了梯度线圈 - 导致真正的“护理点”脑MRI扫描仪。我们通过添加真正的并行接收，改善空间编码以及为第三维编码添加Trase编码来进一步完善该设计。该原型的初步临床评估将对急诊科中轻度至中度出血性脑损伤的患者进行，并在神经系统重症监护病房中具有结构性病变的稳定术患者中进行。

项目成果

Transmit Array Spatial Encoding (TRASE) using broadband WURST pulses for RF spatial encoding in inhomogeneous B0 fields.

• DOI: 10.1016/j.jmr.2016.04.005
• 发表时间: 2016-07
• 期刊: Journal of magnetic resonance (San Diego, Calif. : 1997)
• 作者: Stockmann JP;Cooley CZ;Guerin B;Rosen MS;Wald LL
• 通讯作者: Wald LL

Low-cost and portable MRI.

• DOI: 10.1002/jmri.26942
• 发表时间: 2020-09
• 期刊: JOURNAL OF MAGNETIC RESONANCE IMAGING
• 影响因子: 4.4
• 作者: Wald, Lawrence L.;McDaniel, Patrick C.;Witzel, Thomas;Stockmann, Jason P.;Cooley, Clarissa Zimmerman
• 通讯作者: Cooley, Clarissa Zimmerman