Umek W, Ba-Ssalamah A, Prokesch R, Mallek R, Heimberger K, Hittmair K
Department of Radiology, University of Vienna, AKH, Währinger Gürtel 18-20, A-1090 Vienna, Austria.
Eur Radiol. 1998;8(3):409-15. doi: 10.1007/s003300050402.
The aim of our study was to compare gradient-spin-echo (GRASE) to fast-spin-echo (FSE) sequences for fast T2-weighted MR imaging of the brain. Thirty-one patients with high-signal-intensity lesions on T2-weighted images were examined on a 1.5-T MR system. The FSE and GRASE sequences with identical sequence parameters were obtained and compared side by side. Image assessment criteria included lesion conspicuity, contrast between different types of normal tissue, and image artifacts. In addition, signal-to-noise, contrast-to-noise, and contrast ratios and were determined. The FSE technique demonstrated more lesions than GRASE and with generally better conspicuity. Smaller lesions in particular were better demonstrated on FSE because of lower image noise and slightly weaker image artifacts. Gray-white differentiation was better on FSE. Ferritin and hemosiderin depositions appeared darker on GRASE, which resulted in better contrast. Fatty tissue was less bright on GRASE. With current standard hardware equipment, the FSE technique seems preferable to GRASE for fast T2-weighted routine MR imaging of the brain. For the assessment of hemosiderin or ferritin depositions, GRASE might be considered.
我们研究的目的是比较梯度自旋回波(GRASE)和快速自旋回波(FSE)序列用于脑部快速T2加权磁共振成像的效果。在1.5-T磁共振系统上对31例T2加权图像上有高信号强度病变的患者进行了检查。获取了具有相同序列参数的FSE和GRASE序列并进行并排比较。图像评估标准包括病变的清晰度、不同类型正常组织之间的对比度以及图像伪影。此外,还测定了信噪比、对比噪声比和对比度。FSE技术显示的病变比GRASE更多,且总体清晰度更好。由于图像噪声较低和图像伪影稍弱,特别是较小的病变在FSE上显示得更好。FSE上的灰白质分化更好。铁蛋白和含铁血黄素沉积在GRASE上显得更暗,从而产生了更好的对比度。GRASE上的脂肪组织不太亮。使用当前的标准硬件设备,对于脑部快速T2加权常规磁共振成像,FSE技术似乎比GRASE更可取。对于含铁血黄素或铁蛋白沉积的评估,可以考虑使用GRASE。