Huang Y-C K, Huang T-Y, Chiu H-C, Kuo T-S, Hsueh C-J, Kao H-W, Wang C-W, Hsu H-H, Juan C-J
From the Department of Electrical Engineering (Y.-C.K.H., T.-S.K.), National Taiwan University, Taipei, Taiwan, Republic of ChinaDepartment of Radiology (Y.-C.K.H., C.-J.H., H.-W.K, C.-W.W., H.-H. H., C.-J.J.), Tri-Service General Hospital, Taipei, Taiwan, Republic of China.
Department of Electrical Engineering (T.-Y.H.), National Taiwan University of Science and Technology, Taiwan, Republic of China.
AJNR Am J Neuroradiol. 2014 Jun;35(6):1137-44. doi: 10.3174/ajnr.A3863. Epub 2014 Apr 10.
Current T2-weighted imaging takes >3 minutes to perform, for which the ultrafast transition into driven equilibrium (TIDE) technique may be potentially helpful. This study qualitatively and quantitatively evaluates the imaging of transition into driven equilibrium of the balanced steady-state free precession (TIDE) compared with TSE and turbo gradient spin-echo on T2-weighted MR images.
Thirty healthy volunteers were examined with T2-weighted images by using TIDE, TSE, and turbo gradient spin-echo sequences. Imaging was evaluated qualitatively by 2 independent observers on the basis of a 4-point rating scale regarding contrast characteristics and artifacts behavior. Image SNR and contrast-to-noise ratio were quantitatively assessed.
TIDE provided T2-weighted contrast similar to that in TSE and turbo gradient spin-echo with only one-eighth of the scan time. TIDE showed gray-white matter differentiation and iron-load sensitivity inferior that of TSE and turbo gradient spin-echo, but with improved motion artifacts reduction on qualitative scores. Nonmotion ghosting artifacts were uniquely found in TIDE images. The overall SNRs of TSE were 1.9-2.0 times those of turbo gradient spin-echo and 1.7-2.2 times of those of TIDE for brain tissue (P < .0001). TIDE had a higher contrast-to-noise ratio than TSE (P = .169) and turbo gradient spin-echo (P < .0001) regarding non-iron-containing gray matter versus white matter. TIDE had a lower contrast-to-noise ratio than turbo gradient spin-echo and TSE (P < .0001) between iron-containing gray matter and white matter.
TIDE provides T2-weighted images with reduced scan times and reduced motion artifacts compared with TSE and turbo gradient spin-echo with the trade-off of reduced SNR and poorer gray-white matter differentiation.
当前的T2加权成像需要超过3分钟才能完成,而超快驱动平衡转换(TIDE)技术可能会有所帮助。本研究定性和定量地评估了与TSE和涡轮梯度自旋回波相比,平衡稳态自由进动的驱动平衡转换(TIDE)在T2加权磁共振图像上的成像情况。
30名健康志愿者使用TIDE、TSE和涡轮梯度自旋回波序列进行T2加权成像检查。由2名独立观察者根据4分制评分量表对成像的对比特征和伪影表现进行定性评估。对图像信噪比和对比噪声比进行定量评估。
TIDE提供的T2加权对比度与TSE和涡轮梯度自旋回波相似,但扫描时间仅为其八分之一。TIDE显示出灰质与白质的区分以及对铁负荷的敏感性低于TSE和涡轮梯度自旋回波,但在定性评分上减少运动伪影的效果更好。在TIDE图像中独特地发现了非运动重影伪影。脑组织的TSE总体信噪比是涡轮梯度自旋回波的1.9 - 2.0倍,是TIDE的1.7 - 2.2倍(P < .0001)。对于不含铁的灰质与白质,TIDE的对比噪声比高于TSE(P = .169)和涡轮梯度自旋回波(P < .0001)。在含铁灰质与白质之间,TIDE的对比噪声比低于涡轮梯度自旋回波和TSE(P < .0001)。
与TSE和涡轮梯度自旋回波相比,TIDE能提供扫描时间缩短且运动伪影减少的T2加权图像,但代价是信噪比降低和灰质与白质区分较差。