Technology for Portable MRI

便携式 MRI 技术

基本信息

批准号：
9132788
负责人：
Lawrence L Wald
金额：
$ 59.23万
依托单位：
MASSACHUSETTS GENERAL HOSPITAL
依托单位国家：
美国
项目类别：
财政年份：
2014
资助国家：
美国
起止时间：
2014-09-01 至 2018-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9132788
关键词：
Accident and Emergency department Acute Address Ambulances Area Beds 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 Health Healthcare Helmet Hematoma Hospitals Human Image Intensive Care Units Lesion Location Magnetic Resonance Imaging Maintenance Maps Methods Military Personnel Modeling Monitor Nature Nervous System Trauma Neurologic Neurology Operative Surgical Procedures Pathology Patients Pattern Performance Phase Procedures Protons Rotation Rural Schools Shapes Side 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 image reconstruction imaging system improved instrument light weight magnetic field miniaturize nervous system disorder neuro-oncology neurosurgery novel novel strategies point of care pre-clinical trial prototype reconstruction research clinical testing research study simulation standard of care

项目摘要

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）：自三十多年前诞生以来，磁共振成像 (MRI) 一直是检测和诊断神经系统疾病和损伤的无可争议的护理标准。然而，MRI 扫描仪的成本、重量、尺寸和维护需求通常妨碍它们在一些可能最需要的地方使用，包括急诊室、神经重症监护病房 (ICU)、手术室、运动场、战场、农村医疗场所和救护车。事实上，尽管多个团体尝试小型化和简化 MRI 扫描仪组件，但目前尚不存在真正便携式的“现场护理”MRI 系统。需要一种新方法来创建这样一个真正便携式、经济实惠的脑部扫描仪，这里称为“便携式脑部扫描仪”(PBS)。然而，使传统扫描仪便携化的问题不仅在于需要大的、高度均匀的磁场（需要使用数吨磁铁和低温设备），而且还在于可切换梯度编码场的重量和功耗要求（增加一吨重量和高达 2 MW 的峰值功率）。在这项工作中，我们改进了 PBS 的概念验证原型，并在试点临床测试中将其验证为一种低成本、床旁 MRI 扫描仪，几乎可以放置在任何地方。我们采用一种方法，将磁铁的磁场均匀性要求放宽大约 1000 倍。这样可以实现轻量级永磁体设计，无需制冷剂或功耗。我们的脑磁体原型仅重 45 公斤。与传统成像梯度相比，我们通过使用磁场不均匀性围绕头部旋转该不均匀场，以通用方式空间调制信号，从而实现图像编码并消除笨重、耗电的梯度线圈。具体来说，主磁体的场不均匀性作为编码场，并且图像被重建为迭代逆问题。这种设计“一石二鸟”，既简化了磁铁，又省去了梯度线圈—— 从而产生真正的“即时护理”脑部 MRI 扫描仪。我们通过添加真正的并行接收来进一步完善此设计，以改进空间编码，以及添加第三维的 TRASE 编码。该原型的初步临床评估将在急诊科的一组轻度至中度出血性脑损伤患者以及神经重症监护病房的稳定的结构性病变围手术期患者中进行。