MRI OF CORONARY ARTERIES USING HYPERPOLARIZED HELIUM

这个项目将尝试各种方案来优化对比度 2T时大鼠脑内灰质/白质。几个脉冲序列 将使用：投影、3D IR准备的梯度回波和3D渐变 ECHO，以及FSE。各种翻转角度和TI值将是 在1.5T的结果激励下尝试梯度回波序列。 测量3只大鼠不同脑区的T1、T2和质子密度 Cp(尾壳核)、皮质灰质、丘脑和 穹窿体部。这将允许计算最佳对比度 序列。假设大鼠的大脑包含了大部分 “灰质”，这是令人满意地解决 白质束和流体区域提供的薄边界将 被调查。

This project will try various schemes to optimize the contrast of gray/white matter in the rat brain at 2T. Several pulse sequences will be used: projection, 3D ir-prepped gradient echo and 3D gradient echo, as well as FSE. A variety of flip angles and TI values will be tried for the gradient echo sequences motivated by results at 1.5T. T1, T2 and proton density will be measured in 3 rats in various brain regions such as CP (caudate-putamen), cortical gray, colliculum and corpus callosum. This will allow calculation of optimum contrast sequences. Under the assumption that the rat brain contains mostly 'gray matter', the necessary resolution to satisfactorily resolve the thin boundaries provided by white matter tracts and fluid regions will be investigated.