Joe Bonnie N, Vahidi Kiarash, Zektzer Andrew, Chen Mei-Hsiu, Clifton Matthew S, Butler Thomas, Keshari Kayvan, Kurhanewicz John, Coakley Fergus, Swanson Mark G
Department of Radiology, University of California San Francisco, 1600 Divisadero St., Room C250, Box 1667, San Francisco, CA 94115, USA.
J Magn Reson Imaging. 2008 Dec;28(6):1540-5. doi: 10.1002/jmri.21592.
To determine the intra- and interobserver reproducibility of human amniotic fluid metabolite concentration measurements (including potential markers of fetal lung maturity) detectable by MR spectroscopy.
(1)H high-resolution magic angle spinning (HR-MAS) spectroscopy was performed at 11.7 T on 23 third-trimester amniotic fluid samples. Samples were analyzed quantitatively using 3-(trimethylsilyl)propionic-2,2,3,3-d(4) acid (TSP) as a reference. Four observers independently quantified eight metabolite regions (TSP, lactate doublet and quartet, alanine, citrate, creatinine, choline, and glucose) twice from anonymized, randomized spectra using a semiautomated software program.
Excellent inter- and intraobserver reproducibility was found for all metabolites. Intraclass correlation as a measure of interobserver agreement for the four readers ranged from 0.654 to 0.995. A high correlation of 0.973 was seen for choline in particular, a major component of surfactant. Pearson correlation as a measure of intraobserver reproducibility ranged from 0.478 to 0.999.
Quantification of choline and other metabolite concentrations in amniotic fluid by high-resolution MR spectroscopy can be performed with high inter- and intraobserver reproducibility. Demonstration of reproducible metabolite concentration measurements is a critical first step in the search for biomarkers of fetal lung maturity.
确定通过磁共振波谱法可检测的人羊水代谢物浓度测量（包括胎儿肺成熟度的潜在标志物）的观察者内和观察者间的可重复性。
在11.7T下对23份孕晚期羊水样本进行（1）H高分辨率魔角旋转（HR-MAS）波谱分析。以3-（三甲基硅烷基）丙酸-2,2,3,3-d（4）酸（TSP）作为参考对样本进行定量分析。四名观察者使用半自动软件程序，从匿名的、随机的波谱中对八个代谢物区域（TSP、乳酸双峰和四重峰、丙氨酸、柠檬酸盐、肌酐、胆碱和葡萄糖）进行了两次独立定量。
所有代谢物均具有出色的观察者间和观察者内可重复性。作为四名读者观察者间一致性度量的组内相关性范围为0.654至0.995。特别是表面活性剂的主要成分胆碱，其相关性高达0.973。作为观察者内可重复性度量的Pearson相关性范围为0.478至0.999。
通过高分辨率磁共振波谱法定量羊水胆碱和其他代谢物浓度，可实现高度的观察者间和观察者内可重复性。可重复的代谢物浓度测量证明是寻找胎儿肺成熟生物标志物的关键第一步。
