Assessment of measurement precision in single‐voxel spectroscopy at 7 T: Toward minimal detectable changes of metabolite concentrations in the human brain in vivo
Assessment of measurement precision in single‐voxel spectroscopy at 7 T: Toward minimal detectable changes of metabolite concentrations in the human brain in vivo
复制标题
7 T 下单体素光谱测量精度的评估：实现人脑体内代谢物浓度的最小可检测变化
DOI：
10.1002/mrm.29034
复制
发表时间：
2022
影响因子：
3.3
通讯作者：
Ariane Fillmer
中科院分区：
文献类型：
--
作者：
Layla Tabea Riemann;Christoph Stephan Aigner;Stephen L.R. Ellison;Rüdiger Brühl;Ralf Mekle;Sebastian Schmitter;Oliver Speck;Georg Rose;Bernd Ittermann;Ariane Fillmer
目的介绍一种研究设计和统计分析框架，以评估体内 MRS 测定的代谢物浓度的重复性、再现性和最小可检测变化 (MDC)。方法选择不平衡嵌套研究设计来获取不同重复性和再现性场景下的体内 MRS 数据。 7T 采用自旋回波、全强度采集局部（SPECIAL）序列，利用三种不同的反转脉冲：双曲正割（HS）、梯度偏移独立绝热（GOIA）和宽带、均匀速率、平滑截断（WURST）脉冲。计算了代谢物浓度、Cramér-Rao 下限 (CRLB) 和变异系数 (CV)。进行 Bland-Altman 分析和限制最大似然估计 (REML) 分析来估计测量浓度的重复性和再现性的不同方差贡献。对光谱形状进行 Bland-Altmann 分析，以评估光谱形状的方差，独立于量化模型的影响。结果对于所使用的设置，发现脑代谢物浓度的最小可检测变化在 0.40 µmol/g 至 2.23 µmol/g 之间。 CRLB 仅占代谢物浓度总方差的 16% 至 74%。 SPECIAL 中梯度调制反转脉冲的应用导致重复性略有改善，但总体重现性似乎受到不同会话中定位、校准和其他日常变化的差异的限制。结论引入了一个框架来估计体内 MRS 获得的代谢物浓度的精度，并获得了使用 SPECIAL 在 7 T 下测量的 13 种代谢物浓度的最小可检测变化。
PurposeTo introduce a study design and statistical analysis framework to assess the repeatability, reproducibility, and minimal detectable changes (MDCs) of metabolite concentrations determined by in vivo MRS.MethodsAn unbalanced nested study design was chosen to acquire in vivo MRS data within different repeatability and reproducibility scenarios. A spin‐echo, full‐intensity acquired localized (SPECIAL) sequence was employed at 7 T utlizing three different inversion pulses: a hyperbolic secant (HS), a gradient offset independent adiabaticity (GOIA), and a wideband, uniform rate, smooth truncation (WURST) pulse. Metabolite concentrations, Cramér‐Rao lower bounds (CRLBs) and coefficients of variation (CVs) were calculated. Both Bland‐Altman analysis and a restricted maximum‐likelihood estimation (REML) analysis were performed to estimate the different variance contributions of the repeatability and reproducibility of the measured concentration. A Bland‐Altmann analysis of the spectral shape was performed to assess the variance of the spectral shape, independent of quantification model influences.ResultsFor the used setup, minimal detectable changes of brain metabolite concentrations were found to be between 0.40 µmol/g and 2.23 µmol/g. CRLBs account for only 16 % to 74 % of the total variance of the metabolite concentrations. The application of gradient‐modulated inversion pulses in SPECIAL led to slightly improved repeatability, but overall reproducibility appeared to be limited by differences in positioning, calibration, and other day‐to‐day variations throughout different sessions.ConclusionA framework is introduced to estimate the precision of metabolite concentrations obtained by MRS in vivo, and the minimal detectable changes for 13 metabolite concentrations measured at 7 T using SPECIAL are obtained.
登录
查看更多内容
在 3T 和 7T 临床平台上以超短回波时间增强信号强度的人脑 MR 波谱
影响因子：
3.3
作者：
R. Mekle;V. Mlynárik;G. Gambarota;M. Hergt;G. Krueger;R. Gruetter
通讯作者：
R. Gruetter
适用于 7T 的松弛参数映射以及针对优化的单体素 MRS 的验证
DOI：
--
发表时间：
2013
期刊：
影响因子：
--
作者：
M. Wyss;T. Kirchner;A. Ringenbach;K. Prüssmann;A. Henning
通讯作者：
A. Henning
临床 MRI 系统的切片轮廓改进。
影响因子：
2.5
作者：
J. Mao;H. Yan;J. Fitzsimmons
通讯作者：
J. Fitzsimmons
影响因子：
3.3
作者：
S. Nassirpour;P. Chang;A. Fillmer;A. Henning
通讯作者：
A. Henning
体内 1H MRS 应用
DOI：
--
发表时间：
2010
期刊：
影响因子：
--
作者：
A. Henning
通讯作者：
A. Henning