Reproducibility of total choline/water ratios in mouse U87MG xenograft tumors by 1H-MRS

• Published in: Journal of magnetic resonance imaging 2012-08, Vol.36 (2), p.459-467
• Main Authors: Zhu, Mingming, Fischl, Anthony S., Trowbridge, Melissa A., Shannon, Harlan E.
• Format: Article
• Language: English
• Subjects: 1H-MRS; Animals; Biomarkers, Tumor - analysis; Body Water - chemistry; Cell Line, Tumor; Choline - analysis; Glioblastoma - diagnosis; Glioblastoma - metabolism; Humans; limits of agreement; Magnetic Resonance Imaging - methods; Mice; Protons; reproducibility; Reproducibility of Results; Sensitivity and Specificity; total choline; U87MG; Water - analysis; xenograft
• ISSN: 1053-1807; 1522-2586
• DOI: 10.1002/jmri.23664

Purpose: To evaluate the reproducibility of the measurement of the total choline‐to‐water ratio, and the effect of repositioning the subject between scans, using 1H‐magnetic resonance spectroscopy in a mouse U87MG xenograft model. Materials and Methods: In vivo single‐voxel MR spectra at 7T from xenograft tumors were obtained using both a water‐suppressed and a nonwater‐suppressed point‐resolved spectroscopy (PRESS) sequence. Reproducibility of the total choline/water ratio was evaluated under the conditions of immediate rescan with no change in position of the animal or voxel, immediate reposition, and reposition after 1 or 7 days. Results: Total choline‐to‐water ratios in U87MG tumor xenografts averaged ≈0.018 across all of the groups. The average percent difference between the two scans in each condition was always less than ≈3.0%, and the coefficient of variation was always less than ≈12%. Bias was unrelated to the testing condition and relatively negligible in magnitude (