Anatomically Guided Sodium MRI: Accurately Monitoring Chronic Ion Pump Dysfunction in the Human Brain

项目概要： 该提案致力于开发，临床实施和评价一种新的方法， 用于产生具有无与伦比的分辨率和信噪比的脑钠图像。这种方法是一种 结果或贝叶斯图像重建和流形映射技术的最新发展， 一起使得有可能鲁棒地利用来自高分辨率脑扫描的解剖信息来引导 降低来自较低分辨率、较低信噪比（SNR）脑部扫描的部分体积效应。 尽管这种“限制性重建”方案在MRI成像界一直被提倡， 它们的计算要求、有限的性能和繁重的操作员输入以前限制了它们的 评估和实际的表征，从而使它们不切实际的使用范围内， 临床环境最近，我们已经表明，结合使用分割免费贝叶斯 与流形映射技术一起的方法可以用于提供快速框架， 解剖引导的重建，其中信息形式的高分辨率脑扫描是使用，例行， 提高同时采集的脑部PET扫描的空间分辨率和SNR，从而提高灵敏度 用于检测大脑中的低对比度病变。我们对这种方法的扩展的初步经验是， 大脑的钠MRI产生的图像的空间分辨率和SNR远远超过了 以前使用高和超高磁场强度实现。确定这种方法的局限性 并描述其在临床相关病例中的性能是该提案的主旨。

PROJECT SUMMARY: This proposal is devoted to the development, clinical implementation and evaluation of a novel, methodology for generating brain sodium images of unparalleled resolution and signal-to-noise-ratio. This methodology is a result or recent developments in Bayesian image reconstruction and manifold mapping techniques that together make it possible to robustly utilize anatomical information from high-resolution brain scans to guide the reduction of partial voluming effects from lower resolution, lower signal-to-noise ratio (SNR) brain scans. Though such “constrained reconstruction” schemes have been long-advocated in the MRI imaging community, their computational demands, limited performance and heavy operator input had previously limited their evaluation and practical characterization thus rendering them impractical for use within the confines of a clinical environment. Recently, we have shown that the combined use of segmentation free Bayesian approaches together with manifold mapping techniques can be used to provide a fast framework for Anatomically Guided Reconstruction where the information form high-resolution brain scans is used, routinely, to improve spatial resolution and SNR of concurrently acquired brain PET scans leading to improved sensitivity for the detection of low-contrast lesions in the brain. Our initial experience with extensions of this approach for sodium MRI of the brain has produced images of spatial resolution and SNR that far exceed what had been previously achieved using high and ultra-high magnetic field strengths. Establishing the limits of this approach and characterizing its performance on clinically relevant cases is the thrust of this proposal.