Presurgical functional MRI in patients with large susceptibility artifacts

磁敏感伪影较大的患者的术前功能性 MRI

• 批准号: 9337439
• 负责人: Jun Hua
• 金额: $ 20.2万
• 依托单位: HUGO W. MOSER RES INST KENNEDY KRIEGER
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-01 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9337439
• 关键词: Affect; Air; Area; Brain; Brain Neoplasms; Brain region; Calcified; Clinical; Clinical Protocols; Clinical Research; Cognitive; Craniotomy; Data; Detection; Diagnostic Procedure; Dropout; Echo-Planar Imaging; Epilepsy; Excision; Functional Magnetic Resonance Imaging; Goals; Head; Hemorrhage; Hospitals; Image; Implant; Individual; Language; Magnetic Resonance Imaging; Magnetism; Medical center; Metals; Methods; Morphologic artifacts; Neurosciences; Neurosciences Research; Neurosurgeon; Operative Surgical Procedures; Outcomes Research; Pathology; Patients; Physiologic pulse; Predisposition; Preparation; Protocols documentation; Reproducibility; Research; Running; Scanning; Scheme; Sensitivity and Specificity; Signal Transduction; Structure; Surgically-Created Resection Cavity; Techniques; Temporal Lobe; Time; Tissues; Training; calcification; data acquisition; healthy volunteer; image reconstruction; improved; magnetic field; metallicity; novel; patient subsets; relating to nervous system; temporal measurement; tool; treatment strategy; tumor

PROJECT SUMMARY/ABSTRACT Presurgical fMRI is increasingly performed in large medical centers across the US and in the world, including here at Johns Hopkins. It is commonly used in brain tumor and epilepsy patients to noninvasively locate essential cortical sensorimotor and language areas and to determine the language dominant hemisphere prior to surgery, thus helping to reduce the need for invasive diagnostic procedures such as intraoperative cortical stimulation mapping. However, a significant subpopulation of patients undergoing presurgical fMRI are affected by the well-known problems of geometric distortion and signal dropout (thus compromised sensitivity) in regions with large magnetic susceptibility effects when using the current standard BOLD fMRI method: gradient echo (GRE) echo-planar-imaging (EPI). These include several frontal and temporal regions particularly relevant for language mapping in presurgical fMRI. Furthermore, such susceptibility artifacts can also arise from cavities related to previous surgery, calcified structures, hemorrhage, and metal implants. For instance, about 25% of our presurgical fMRI referrals have undergone prior resection and are being considered for a second resection, who will suffer from susceptibility artifacts related to resection cavities and surgical metallic craniotomy hardware. Although many methods have been developed to mitigate these problems, most are region dependent or require extra data acquisition. We have recently developed a T2-prepared (T2prep) BOLD fMRI method, which showed minimal distortion and dropout and sufficient BOLD sensitivity in the entire brain even in the presence of metallic head implants, and superior BOLD sensitivity than GRE EPI in regions affected by large susceptibility artifacts. The method was initially developed at ultra-high magnetic field (7 Tesla, 7T). The goal of this R21 is to optimize and validate T2prep BOLD for presurgical fMRI in tumor patients on 3T clinical MRI scanners. Aim 1: To optimize whole-brain T2prep BOLD fMRI for typical presurgical fMRI paradigms in healthy volunteers on 3T clinical MRI scanners. The multiband techniques will be implemented for T2prep BOLD. Image quality, functional sensitivity and specificity (in regions with small or large susceptibility effects) will be compared with GRE EPI BOLD fMRI (current standard). Aim 2: To determine whether T2prep BOLD fMRI can be used as a complementary method for presurgical planning in brain tumor patients with large susceptibility artifacts at 3T. Functional results from patients using typical presurgical fMRI paradigms will be compared between T2prep BOLD and GRE EPI BOLD fMRI, and will be validated by intraoperative cortical stimulation mapping data. If the proposed research is successful, it is expected to benefit a significant subset of patients undergoing presurgical fMRI. As presurgical fMRI protocols often consist of several functional scans, T2prep BOLD fMRI can be feasibly incorporated into existing clinical protocols. Besides, we also expect the T2prep BOLD approach to be useful for other functional studies in neuroscience and clinical research as an alternative fMRI tool that can assess brain functions in previously less explored brain territories due to susceptibility related signal losses in EPI BOLD fMRI.

项目摘要/摘要 术前fMRI越来越多地在美国和世界各地的大型医疗中心进行，包括 在约翰·霍普金斯（Johns Hopkins）。它通常用于脑肿瘤和癫痫患者，可无创定位必不可少 皮质感觉运动和语言区域，并在手术前确定语言主导的半球 因此有助于减少对侵入性诊断程序的需求，例如术中皮质刺激 映射。然而，受到术前fMRI的患者的显着亚群受到 几何失真和信号辍学的问题（从而损害灵敏度）的众所周知的问题 当使用当前标准BOLD FMRI方法时，磁敏感性较大：梯度回声（GRE） 回声平面成像（EPI）。其中包括几个与语言特别相关的额叶和时间区域 绘图术前fMRI。此外，这种敏感性伪像也可能是由与 先前的手术，钙化结构，出血和金属植入物。例如，我们约有25％ 术前FMRI转诊已经进行了事先切除，并正在考虑进行第二次切除， 将遭受与切除腔和手术金属颅骨手术硬件有关的敏感伪像。 尽管已经开发了许多方法来减轻这些问题，但大多数是区域依赖或需要的 额外的数据获取。我们最近开发了一种预先准备的（T2PREP）BOLD FMRI方法，该方法显示 即使在有金属的情况下 在受大敏感性伪像的区域中，头部植入物和比GRE EPI优于GRE EPI。 该方法最初是在超高磁场（7 Tesla，7t）上开发的。 R21的目标是优化 并在3T临床MRI扫描仪上验证肿瘤患者的T2PREP BOLD t2PREP BOLD。目标1：优化 在3T临床MRI上，健康志愿者的典型前fMRI范例的全脑T2PREP BOLD FMRI 扫描仪。将针对T2PREP BOLD实施多频道技术。图像质量，功能灵敏度 将特异性（在具有较小敏感性效果的区域中）与Gre Epi Bold fMRI进行比较 （当前标准）。目标2：确定T2PREP BOLD FMRI是否可以用作补充方法 用于脑肿瘤患者的术前计划，该患者在3T时具有较大的敏感性伪影。功能结果 将比较使用典型的前fMRI范式的患者在T2PREP BOLD和GRE EPI BOLD之间进行比较 fMRI，将通过术中皮质刺激映射数据进行验证。如果拟议的研究是 成功的，预计将受益于大量接受术前功能磁共振成像的患者。作为术前 fMRI协议通常由几项功能扫描组成，T2PREP BOLD FMRI可以可行地纳入 现有的临床方案。此外，我们还期望T2PREP粗体方法对其他功能有用 神经科学和临床研究的研究是可以评估大脑功能的替代FMRI工具 以前，由于EPI BOLD fMRI中易感性相关的信号损失，探索较少的大脑领土。