MAGNETIC RESONANCE ELASTOGRAPHY

人们很早就知道，恶性肿瘤的特点是 通过与周围环境本质上不同的机械性能 正常组织。这就解释了触诊作为一种 在可接近的区域检测癌症的临床技术 尸体。事实上，大多数甲状腺、乳腺和前列腺肿瘤都是 仍然是通过这种有数百年历史的诊断技术首次发现的。 不幸的是，小的或无法触及的病变不能通过 触摸和传统的诊断成像方法，例如 超声波、计算机断层扫描(CT)和磁共振成像 (MRI)不提供以任何方式类似的信息。 本提案的目标是开发和验证诊断 定量勾画机械结构的成像技术 组织的特性。建议的技术应用于机械 波到组织并通过分析组织和测量区域弹性 波的传播模式。这款新产品的关键组件 技术是最近发展起来的一种直接观察的方法 在组织中传播声波，使用MRI序列 同步运动敏感渐变。的中心假说 这项工作表明，所提出的技术是可以成功的 作为一种临床工具实施，并将对 检测和描述局灶性和弥漫性疾病过程 这可能很难用其他方法进行调查。 研究计划包括以下方面的调查(一) 改进磁共振声波成像序列，(2)研制 对组织施加声波的有效方法，(3) 提炼了所需的图像处理方法，(4)研究了 该技术在组织表征方面的潜力，以及(5) 将这项技术应用于人体研究。这些方法将 包括理论工作、基本MRI脉冲序列开发 设备工程，动物和人体组织标本的研究， 以及正常志愿者和患者志愿者的试验，特别强调 优化乳腺癌检测技术。 如果研究成功，它将产生一种新的诊断方法 成像工具，可：(I)提供一种非侵入性“触诊”的方法 通过成像“身体的某些区域，这些区域超出了 医生的手，(2)在肿瘤足够大之前勾勒出它们 通过触摸检测，(3)为评估提供更高的灵敏度 组织弹性的变化，以及(4)提供了有用的新的 用于描述组织特征的定量工具。

It has long been known that malignant tumors are often characterized by substantially different mechanical properties than surrounding normal tissue. This accounts for the efficacy of palpation as a clinical technique to detect cancer in accessible regions of the body. Indeed, most tumors of the thyroid, breast, and prostate are still first detected by this centuries-old diagnostic technique. Unfortunately, small or inaccessible lesions cannot be detected by touch, and conventional diagnostic imaging methods such as ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI) do not provide information that is in any way analogous. The goal of this proposal is to develop and validate a diagnostic imaging technique for quantitatively delineating mechanical properties of tissues. The proposed technique applies mechanical waves to tissue and measures regional elasticity by analyzing the pattern of wave propagation. A critical component of this new technique is a recently-developed method for directly observing propagating acoustic waves in tissue, using an MRI sequence with synchronous motion-sensitizing gradients. The central hypothesis of this work is that the proposed technique can be successfully implemented as a clinical tool and that it will be useful for detecting and characterizing focal and diffuse disease processes that may be difficult to investigate by other methods. The research plan includes investigations in the following areas (I) improving the MR acoustic wave imaging sequence, (2) developing effective methods for applying acoustic waves to tissue, (3) refining the required image processing methods, (4) studying the potential of the technique for tissue characterization, and (5) implementing the technique in human studies. The methods will encompass theoretical work, basic MRI pulse sequence development, device engineering, studies of animal and human tissue specimens, and trials with normal and patient volunteer's, special emphasis on optimizing the technique for breast cancer detection. If the research is successful, it will yield a new diagnostic imaging tool that may: (I) provide a means to noninvasively "palpate by imaging" regions of the body that are beyond the reach of the physician's hand, (2) delineate tumors before they are large enough to detect by touch, (3) provide greater sensitivity for assessing changes in tissue elasticity, and (4) provide a useful new quantitative tool for characterizing tissue.