Magnetic Resonance Imaging Near Metallic Implants

描述（由申请人提供）：本项目的目标是解决磁共振成像（MRI）在评估金属植入物患者时的基本局限性。我们将开发一种完整的三维畸变校正成像和重建技术，提供无金属诱发伪影的诊断图像。我们还将提供不同的对比机制来成像近金属。所有的技术都将在尸体模型和体内脊椎植入物中进行验证。相关性：MRI被广泛认为是骨科疾病的最佳成像方式，如骨髓炎、血管坏死、肌腱或韧带损伤、骨或软组织病变、脊神经根受压和椎管狭窄。不幸的是，在使用金属植入物的患者中，MRI会受到金属诱发的伪影（例如，严重的信号丢失、扭曲）和植入物附近脂肪抑制失败的影响。这些正是术后并发症可能发生的位置，因此准确的成像可能具有最大的临床影响。方法：本项目解决了在金属植入物附近进行MRI的这些技术挑战。我们的方法是开发新的脉冲序列，不需要额外的硬件，可以在1.5T MRI系统的大型安装基础上使用。具体来说，我们的目标是：(1)开发3D成像方法来消除所有金属诱发的伪影；(2)在金属存在下开发更强大的脂肪抑制；(3)在尸体研究中评估我们的成像方法，随后对12名先前接受过脊柱植入物的患者进行研究。在资助期结束时，我们将开发出在金属植入物附近提供无失真图像和健壮脂肪抑制的方法。该项目的成功将改善数百万患者的诊断和治疗。公共卫生相关性：金属植入物越来越多地被用于治疗脊柱、髋关节和膝关节的慢性和急性损伤。磁共振成像（MRI）通常用于评估骨科疾病，但由于金属引起的严重磁场不均匀性，在金属植入物附近失效。该研究项目将开发金属引起的扭曲的完整3D校正，从根本上改善植入物附近的MRI。

DESCRIPTION (provided by applicant): The goals of this project are to address the fundamental limitations of magnetic resonance imaging (MRI) in evaluating patients with metallic implants. We will develop a complete 3D distortion- corrected imaging and reconstruction technique that provides diagnostic images without metal-induced artifacts. We will also provide different contrast mechanisms for imaging near metal. All the techniques will be validated in a cadaveric model and in vivo in subjects with spinal implants. Relevance: MRI is widely regarded as the best imaging modality for orthopedic conditions such as osteomyelitis, a vascular necrosis, tendon or ligamentous injury, bone or soft tissue lesions, spinal nerve root compression, and spinal stenosis. Unfortunately, in patients with metallic implants, MRI is hampered by metal-induced artifacts (e.g., severe signal loss, distortions), and failure of fat suppression at the locations near the implants. These are precisely the locations where post-surgical complications are likely to occur, and thus where accurate imaging could have the greatest clinical impact. Approach: This project addresses these technical challenges of performing MRI near metallic implants. Our approach is to develop new pulse sequences that require no additional hardware and can be utilized on the large installed base of 1.5T MRI systems. Specifically, we aim to (1) develop 3D imaging methods to eliminate all metal-induced artifacts, (2) develop more robust fat suppression in the presence of metal, and (3) evaluate our imaging methods in a cadaver study, followed by a study of 12 patients who have previously received spinal implants. At the end of the funding period, we will have developed methods that provide distortion- free images and robust fat suppression near metallic implants. The success of this project will improve the diagnosis and treatment of millions of patients. PUBLIC HEALTH RELEVANCE: Metallic implants are being used increasingly to treat chronic and acute injuries to the spine, hip and knee. Magnetic resonance imaging (MRI) is commonly used for evaluating orthopedic conditions, but fails near metallic implants due to severe magnetic field inhomogeneities caused by metal. This research project will develop complete 3D correction of metal-induced distortions to radically improve MRI near implants.