Bhattacharyya P K, Lowe M J, Phillips M D
Division of Radiology, Cleveland Clinic, Foundation, Cleveland, Ohio 44195, USA.
Magn Reson Med. 2007 Oct;58(4):808-12. doi: 10.1002/mrm.21337.
Motion has an adverse effect on spectral quality and needs to be properly identified in MR spectroscopy (MRS) scans. Spectral subtraction-based techniques like J-difference editing are prone to be affected more by subject motion where motion can result in false peaks or inefficient subtraction of peaks. Introducing a water signal-based interleaved navigator scan in the MEGA point-resolved spectroscopy (MEGA-PRESS) sequence and acquiring data on a shot-by-shot basis, subject motion inside a scanner was tracked and motion-corrupted data were identified and excluded from the dataset. Performing a gamma-aminobutyric acid (GABA) editing scan at the occipital cortex, it was possible to retrieve a properly edited GABA spectrum from a dataset otherwise to be discarded due to motion. This study demonstrates the importance of independent motion assessment in J-difference editing.
运动对频谱质量有不利影响,在磁共振波谱(MRS)扫描中需要对其进行正确识别。像J-差分编辑这样基于频谱减法的技术更容易受到受试者运动的影响,运动可能会导致出现假峰或峰的减法效率低下。在MEGA点分辨波谱(MEGA-PRESS)序列中引入基于水信号的交错导航扫描,并逐次采集数据,对扫描仪内的受试者运动进行跟踪,识别出受运动影响的数据并将其从数据集中排除。在枕叶皮质进行γ-氨基丁酸(GABA)编辑扫描时,能够从原本因运动而要丢弃的数据集中检索出经过正确编辑的GABA频谱。本研究证明了在J-差分编辑中进行独立运动评估的重要性。