鼠肝MR成像技术参数探讨

探寻大白鼠肝脏MR成像序列及参数。材料和方法:采用GE0.5T Veetra MR成像仪匹配的SE序列,选择不同大小的像素及TR、TE进行MR成像,然后根据图像的解剖结构图像的均一性,伪影信噪比(SNR),对比噪声比(CNR),和对癌灶的显示,判断图像的优劣,分析不同的成像参数对图像的影响。结果:像素为0.491mm(成像孔径11cm,成像矩阵224×128)时,T_1加权图像的SNR,CNR及优质率分别为17.851±1.774,14.333±3.152,及77.78％(7/9),T_2加权图像的SNR,CNR及优质率分别为8.851±2.518,7.435±1.096及77.78％(7/9);像素为0.351mm(成像孔径9cm,成像矩阵256×160)时,T_1加权图像的SNR,CNR及优质率分别为9.207±1.644,8.203±0.657,及20％(1/5),T_2加权图像SNR,CNR及优质率分别为5.961±1.326,4.463±0.590及20％(1/5)。前者明显后者(P<0.05)。TR 2000ms图像的清晰度和对癌灶显示能力较TR 1500,2500ms为好;TE 30ms,80ms较60ms,120ms好。结论:T_1加权像(TR 480ms,TE 21ms),T_2加权像(TR 2000ms,TE 30/80ms)像素0.491mm是GE0.5T Vectra鼠肝MR成像较为理想的成像参数。

The Study of Parameters of MR Imaging in Mouse Liver

To investigate sequences and paramters of MR imaging in mouse liver. Methods: The mouse liver images were obtained by SE sequence with different pixel, TE and TR The effects on MR images quality were analyzed, the quality of images was assessed by anatomy, homogenous, artifact, SNR, CNR and revealing for lesions of carcinoma. Results: The image of T1WI and T2WI at 0.491mm pixel was better than at 0.351mm. The quality of imagewith TR at 2000ms was better than 1500ms and 2500ms, the quality of image with TE at 30 and 80ms was better than 60ms and 120ms. Conclusion: T1WI(TR480ms, TE21ms), T2WI(TR2000ms, TE30ms and 80ms), at 0.491mm pixel is fairly ideal parameters of MR1 for mouse liver with GE 0. 5T Vectra MR imager.