PROTON MRS FOR DETECTING AXONAL PATHOLOGY IN SPLENIUM OF BRAIN INJURED PATS

质子磁共振波谱提供了一种显示轴突的方法 创伤性脑损伤后的生存能力。质子磁共振波谱可以很容易地检测到 N-乙酰天冬氨酸的水平，这是一种专门在 神经元和轴突。弥漫性脑损伤选择性损伤白色 物质因其产生的高惯性应变而运动 旋转的加速和减速。质子磁共振波谱可能是 有利于评估创伤性脑损伤患者，活体内， 用于弥漫性损伤。这项工作的重点是确定 正常和创伤性脑压部的波谱特征 受伤的病人。痂状体，尤其是压部，是一种 易受剪切力影响而产生的DAI。调查结果来自 我们的研究表明，正常脾组织中NAA/Cr升高 与正常脑叶白质相比。的光谱分析 压部与叶白质不同。考查 在35例创伤性脑损伤中，有一组人 压部NAA/Cr值明显低于正常 控制受试者。35例中有24例呈下降趋势 NAA/Cr与对照组的平均NAA/Cr进行比较。十一 2例压部NAA/Cr值低的患者MRI平淡或正常 考试。所有11例患者均有神经创伤后遗症。 足以需要门诊康复治疗。下降 压部的NAA/Cr值可能是弥漫性弥散的标志 受伤。质子磁共振光谱学检查可能特别有用。 轻度脑损伤患者有不明原因的神经学和 认知缺陷。NAA对神经元和轴突的耗竭 剪裁可能是造成这些赤字的原因。质子磁共振 光谱学可能被证明是一种有用的工具来确定这种类型的 受伤。未来的努力集中在利用多片化学物质 移位成像(CSI)技术检查区域NAA水平。

Proton MR spectroscopy provides a method for indicating axonal viability after traumatic brain injury. Proton MRS can readily detect levels of N-acetyl aspartate, a chemical synthesized exclusively in neurons and axons. Diffuse brain injury selectively injures white matter tracts because of the high inertial strain created as a result of rotational acceleration and deceleration. Proton MRS may be beneficial in evaluating traumatic brain injured patients, in vivo, for diffuse injury. This work focused upon determining the spectroscopic profile of the splenium in normal and traumatic brain injured patients. The corpus callosum, especially the splenium, is a vulnerable site for shearing forces producing DAI. The findings from our investigation was that NAA/Cr in the normal splenium is elevated compared to normal lobar white matter. The spectroscopic profile of the splenium is distinct from that of lobar white matter. Examination of thirty five cases of traumatic brain inju ry show a population with a significantly lower NAA/Cr in the splenium compared to normal control subjects. Twenty four of the thirty five cases showed lowered NAA/Cr compared to the mean NAA/Cr found in control subjects. Eleven cases with low NAA/Cr in the splenium had unremarkable or normal MRI examinations. All eleven cases suffered neurotrauma sequelae sufficient to require outpatient rehabilitation treatment. Declines in NAA/Cr of the splenium may be a marker for widespread diffuse injury. A proton MR spectroscopy examination may be of particular use for patients with mild brain injury having unexplained neurologic and cognitive deficits. The depletion of NAA upon neuronal and axonal shearing may be responsible for these deficits. Proton MR spectroscopy may prove a useful tool for determining this type of injury. Future efforts are focused upon utilizing multislice chemical shift imaging (CSI) techniques to examine regional NAA levels.