GE Global Research Center, Niskayuna, New York 12309, USA.
Magn Reson Med. 2011 Jun;65(6):1515-21. doi: 10.1002/mrm.22749. Epub 2011 Jan 10.
A 3-T study is presented, comparing the ability of two (1) H spectroscopy pulse sequences, Carr-Purcell point resolved spectroscopy (CPRESS; TE = 45 msec), and conventional PRESS (TE = 35 msec), to separate between groups of 20 normal control (NC) and 20 mild cognitive impairment (MCI) subjects. Both sequences showed higher myo-inositol (mI) and mI/N-acetyl-aspartate (NAA) levels in the posterior cingulate gyrus of the MCI subjects. The increased intrasubject repeatability of mI and mI/NAA CPRESS measurements (∼ 6% vs. 9% for PRESS) translated into decreased intraclass variability. A 22% intraclass mI PRESS variability was reduced to 16% for CPRESS, and an 18% intraclass mI/NAA PRESS variability was reduced to 12% for CPRESS for the group of NC subjects. Similar results were observed for the MCI subjects. Decreased intraclass variability led to improved separation between NC and MCI subjects (P = 0.017 for PRESS and P < 0.0001 for CPRESS mI/NAA, the best NC/MCI discriminant for each method). Seventy-five percent sensitivity at eighty percent specificity was demonstrated by mI/NAA CPRESS measurements in separating NC from MCI subjects. High correlations were also observed between subject performance on a number of neuropsychological tests (probing verbal memory, visuoconstruction performance, and visual motor integration) and the mI/NAA ratio; higher correlation coefficients (with stronger statistical significance) were consistently evident for CPRESS than for PRESS data.
本文呈现了一项 3T 研究，比较了两种（1）H 波谱脉冲序列，即 Carr-Purcell 点分辨波谱（CPRESS；TE = 45msec）和传统的 PRESS（TE = 35msec），以区分 20 名正常对照（NC）和 20 名轻度认知障碍（MCI）受试者组。两种序列均显示 MCI 受试者后扣带回的肌醇（mI）和 mI/N-乙酰天冬氨酸（NAA）水平升高。CPRESS 测量的 mI 和 mI/NAA 指标的受试者内重复性增加（约 6%比 PRESS 的 9%），导致组内变异性降低。22%的组内 mI PRESS 变异性降低到 CPRESS 的 16%，18%的组内 mI/NAA PRESS 变异性降低到 CPRESS 的 12%，NC 组受试者。MCI 受试者也观察到了类似的结果。组内变异性降低导致 NC 和 MCI 受试者之间的分离得到改善（PRESS 为 0.017，CPRESS mI/NAA 为 P < 0.0001，这是每种方法的最佳 NC/MCI 判别）。CPRESS 测量的 mI/NAA 在区分 NC 和 MCI 受试者方面具有 75%的灵敏度和 80%的特异性。还观察到受试者在多项神经心理学测试（探测言语记忆、视空间建构表现和视觉运动整合）上的表现与 mI/NAA 比值之间存在高度相关性；CPRESS 数据的相关系数（具有更强的统计学意义）始终高于 PRESS 数据。
