Fellner F, Fellner C, Held P, Schmitt R
Department of Neuroradiology, Oberösterreichische Landesnervenklinik, Linz, Austria.
AJNR Am J Neuroradiol. 1997 Oct;18(9):1617-25.
To determine the value of the gradient- and spin-echo (GRASE) technique as compared with the fast spin-echo and conventional spin-echo techniques in MR imaging of the brain.
Sixty-six patients with ischemic and neoplastic brain lesions were examined with T2-weighted spin-echo, fast spin-echo, and GRASE sequences. Three independent observers evaluated the contrast characteristics of anatomic and pathologic structures and of artifacts. Quantitative image analysis included region-of-interest measurements of anatomic structures and lesions.
The contrast of anatomic structures was superior in images obtained with conventional and fast spin-echo techniques as compared with those obtained with the GRASE technique. Extended lesions, such as tumors and territorial infarcts, were identified equally with all techniques. For delineation of small ischemic lesions, GRASE was slightly inferior to fast and conventional spin-echo sequences. Flow artifacts were considerably reduced with fast spin-echo and GRASE sequences. Chemical-shift artifacts were significantly reduced, but ringing artifacts were more pronounced with GRASE.
Fast spin-echo remains the standard technique in MR imaging of the brain. However, GRASE might be useful in special cases, such as with uncooperative patients whose conventional or fast spin-echo images show severe motion artifacts.
在脑部磁共振成像中，将梯度与自旋回波（GRASE）技术与快速自旋回波和传统自旋回波技术相比较，以确定其价值。
对66例患有缺血性和肿瘤性脑病变的患者，采用T2加权自旋回波、快速自旋回波和GRASE序列进行检查。三名独立观察者评估了解剖和病理结构以及伪影的对比特征。定量图像分析包括对解剖结构和病变的感兴趣区测量。
与GRASE技术获得的图像相比，传统和快速自旋回波技术获得的图像中解剖结构的对比度更高。所有技术对肿瘤和大面积梗死等扩展病变的识别效果相同。对于小缺血性病变的描绘，GRASE略逊于快速和传统自旋回波序列。快速自旋回波和GRASE序列可显著减少流动伪影。化学位移伪影显著减少，但GRASE的振铃伪影更明显。
快速自旋回波仍然是脑部磁共振成像的标准技术。然而，GRASE在特殊情况下可能有用，例如对于传统或快速自旋回波图像显示严重运动伪影的不合作患者。
