Yen Yi-Fen, Field Aaron S, Martin Eric M, Ari Narter, Burdette Jonathan H, Moody Dixon M, Takahashi Atsushi M
Department of Medical Engineering, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA.
Magn Reson Med. 2002 May;47(5):921-8. doi: 10.1002/mrm.10140.
The reproducibility of quantitative cerebral blood flow (CBF) measurements using MRI with arterial spin labeling and acetazolamide challenge was assessed in 12 normal subjects, each undergoing the identical experimental procedure on two separate days. CBF was measured on a 1.5T scanner using a flow-sensitive alternating inversion recovery (FAIR) pulse sequence, performed both at baseline and 12 min after intravenous administration of acetazolamide. T(1) was measured in conjunction with the FAIR scan in order to calculate quantitative CBF. The CBF maps were segmented to separate gray matter (GM) from white matter (WM) for region-of-interest (ROI) analyses. Post- acetazolamide CBF values (ml/100 g/min, mean +/- SD) of 87.5 +/- 12.5 (GM) and 46.1 +/- 10.8 (WM) represented percent increases of 37.7% +/- 24.4% (GM) and 40.1% +/- 24.4% (WM). Day-to-day differences in baseline CBF were -1.7 +/- 6.9 (GM) and -1.4 +/- 4.7 (WM) or, relative to the mean CBF over both days for each subject, -2.5% +/- 11.7% (GM) and -3.8% +/- 13.6% (WM) Day- to-day differences in absolute post-ACZ CBF increase were -2.5 +/- 6.8 (GM) and 2.7 +/- 9.4 (WM) or, relative to the mean CBF increase over both days for each subject, -4.7% +/- 13.3% (GM) and 9.1% +/- 26.2% (WM). Thus, FAIR- based CBF measurements show satisfactory reproducibility from day to day, but with sufficient variation to warrant caution in interpreting longitudinal data. The hemispheric asymmetry of baseline CBF and post-acetazolamide CBF increases varied within a narrower range and should be sensitive to small changes related to disease or treatment.
在12名正常受试者中评估了使用磁共振成像（MRI）结合动脉自旋标记和乙酰唑胺激发来定量测量脑血流量（CBF）的可重复性，每位受试者在两个不同日期接受相同的实验程序。使用流敏感交替反转恢复（FAIR）脉冲序列在1.5T扫描仪上测量CBF，分别在基线时以及静脉注射乙酰唑胺后12分钟进行测量。结合FAIR扫描测量T(1)以计算定量CBF。将CBF图进行分割，以将灰质（GM）与白质（WM）分开，用于感兴趣区域（ROI）分析。乙酰唑胺激发后的CBF值（ml/100 g/min，平均值±标准差），灰质为87.5±12.5，白质为46.1±10.8，分别代表增加了37.7%±24.4%（灰质）和40.1%±24.4%（白质）。基线CBF的每日差异，灰质为-1.7±6.9，白质为-1.4±4.7；或者相对于每位受试者两天的平均CBF，灰质为-2.5%±11.7%，白质为-3.8%±13.6%。乙酰唑胺激发后CBF绝对增加量的每日差异，灰质为-2.5±6.8，白质为2.7±9.4；或者相对于每位受试者两天的平均CBF增加量，灰质为-4.7%±13.3%，白质为9.1%±26.2%。因此，基于FAIR的CBF测量显示出令人满意的每日可重复性，但存在足够的变异性，在解释纵向数据时需谨慎。基线CBF和乙酰唑胺激发后CBF增加的半球不对称性在较窄范围内变化，并且应该对与疾病或治疗相关的微小变化敏感。
