Finelli D A, Hurst G C, Amantia P, Gullapali R P, Apicella A
Department of Radiology, Case Western Reserve University School of Medicine, MetroHealth Medical Center, Cleveland, OH 44109-1998, USA.
Radiology. 1996 Apr;199(1):219-26. doi: 10.1148/radiology.199.1.8633148.
To evaluate white matter disorders with magnetization transfer (MT) techniques.
In 46 healthy volunteers and 46 clinical patients, MT Z spectra were obtained with various continuous-wave-equivalent MT powers (B1CW) and frequency offsets.
With B1CW of 270 Hz and 4,000-Hz frequency offset, the MT ratio of normal callosal white matter was 59.2% +/- 1.5 (standard deviation), with less than 5% contribution from direct saturation and spin locking. A small statistically significant (P < .01) regional variation in normal white matter was seen. Plaques in MS patients had a broad (or wide) range of MT ratios; normal appearing white matter had a slightly reduced MT ratio. Vasogenic edema had a minimal effect on MT ratio, and radiation necrosis showed prominent reductions in MT ratio.
High MT power techniques can expand the dynamic range of MT ratios, maintain a relatively pure MT effect, and be used effectively in MT imaging to evaluate white matter disorders.
利用磁化传递（MT）技术评估白质病变。
对46名健康志愿者和46名临床患者，采用不同的连续波等效MT功率（B1CW）和频率偏移获取MT Z谱。
在B1CW为270 Hz且频率偏移为4000 Hz时，正常胼胝体白质的MT比率为59.2%±1.5（标准差），直接饱和及自旋锁定的贡献小于5%。正常白质存在微小但具有统计学意义（P<.01）的区域差异。多发性硬化症（MS）患者的斑块具有广泛的MT比率范围；外观正常的白质MT比率略有降低。血管源性水肿对MT比率影响极小，放射性坏死则表现为MT比率显著降低。
高MT功率技术可扩大MT比率的动态范围，维持相对纯净的MT效应，并能有效地用于MT成像以评估白质病变。
