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方面的根本局限性。我们将开发一种完整的3D失真校正成像和重建技术，提供没有金属诱导伪影的诊断图像。我们还将为近金属成像提供不同的对比度机制。所有这些技术都将在身体模型和脊柱植入物的受试者体内得到验证。相关性：MRI被广泛认为是骨髓炎、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等骨科疾病的最佳成像方式。不幸的是，在金属植入物的患者中，磁共振成像受到金属诱导的伪影(例如，严重的信号丢失、失真)和植入物附近脂肪抑制失败的阻碍。这些正是手术后并发症可能发生的地方，因此准确的成像可能会产生最大的临床影响。方法：这个项目解决了在金属植入物附近进行磁共振成像的这些技术挑战。我们的方法是开发新的脉冲序列，这种序列不需要额外的硬件，可以在1.5T磁共振系统的大量安装基础上使用。具体地说，我们的目标是(1)开发3D成像方法以消除所有金属诱导的伪影，(2)在金属存在的情况下开发更强大的脂肪抑制，以及(3)在身体研究中评估我们的成像方法，随后对12名以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强大的脂肪抑制的方法。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：金属植入物正越来越多地被用于治疗脊柱、髋关节和膝盖的慢性和急性损伤。磁共振成像(MRI)通常用于评估骨科状况，但由于金属引起的严重磁场不均匀，在金属植入物附近无法使用。这项研究项目将开发金属引起的扭曲的完全3D校正，以从根本上改善种植体附近的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.