MRI增强T1高分辨力各同性容积激发序列与TSET1W序列检出椎体转移瘤的对比分析

Comparative analysis of detection of spinal metastases with contrast-enhanced MRI T1 high resolution isotropic volume excitation and TSE T1WI sequence

目的比较增强MRI快速T1高分辨力各向同性容积激发(THRIVE)序列和TSE序列T1W检出椎体转移瘤的价值。方法对31例经穿刺活检病理证实的椎体转移瘤患者行MR增强检查,增强后先后行常规矢状位TSE T1W序列和矢状位THRIVE序列扫描。比较2个序列显示转移瘤病灶的数目、SNR、CNR和病灶边缘清晰度、运动伪影评分。结果 TSE T1W序列和THRIVE序列扫描时间分别为2min 55s和33s。增强后THRIVE序列显示病灶的数量与TSE T1W序列差异无统计学意义(Z=-0.816,P=0.414)。增强后THRIVE序列的SNR(432.54±271.60)、CNR(233.27±197.65)均低于TSE T1W序列的SNR(674.32±375.79)、CNR(312.38±207.49),差异均有统计学意义(t=-4.366、-2.660,P<0.001、0.012)。TSE T1W序列显示病灶边缘较THRIVE序列清晰(Z=-4.082,P<0.001),但运动伪影较THRIVE序列明显(Z=2.291,P=0.022)。结论增强扫描THRIVE序列扫描时间短,运动伪影少,椎体转移瘤的检出数目与TSE T1WI序列相当,在椎体转移瘤的检查中取代TSE T1W序列具有可行性。

Objective To compare the usefulness of contrast-enhanced T1 high resolution isotropic volume excitation（THRIVE）sequence and fat-saturated TSE sequence in detection of spinal metastases.Methods Thirty-one consecutive patients with spinal metastases were recruited.All patients received post-contrast TSE T1 WI followed by a fat-suppressed THRIVE sequence.The number of lesions,SNR and CNR for both sequences,and the scoring of image quality concerning motion-artifact and tumor conspicuity were compared.Results Acquisition time of the post-contrast TSE T1 W sequence and the THRIVE sequence was 2min 55 sand 33s,respectively.No significant difference was found in the number of lesions detected between the two sequences（Z=-0.816,P=0.414）.The SNR（432.54±271.60）and CNR（233.27±197.65）of the THRIVE sequence were significantly lower than the SNR（674.32±375.79）and CNR（312.38±207.49）of the TSE T1 Wsequence respectively（t=-4.366,-2.660,P〈0.001,0.012）.Tumor conspicuity of the post-contrast TSE sequence was better than that of THRIVE sequence（Z=-4.082,P〈0.001）,while the motion-artifact in TSE sequence was more severe（Z=2.291,P=0.022）.Conclusion The post-contrast THRIVE sequence is capable of decreasing acquisition time and motion-artifact.Besides,its detected efficacy is equal to that of TSE sequence.There is practical possibility to replace the conventional post-contrast TSE T1 WI sequence with the THRIVE sequence in the imaging of spinal metastases.