刀锋伪影校正技术在头部运动伪影纠正的应用

Clinical Application of MR BLADE Techniques in Correcting Head Motion Artifacts

目的:探讨刀锋伪影校正(BLADE)技术在MRI头部运动伪影纠正方面的应用价值。方法:15例健康志愿者行常规头颅MRI检查,后行BLADE序列扫描(轴位T2WI、矢状位T1WI、轴位T1WI),其中10例在每次扫描启动后20s、40s、60s作左右30°的转动各一次,每次在2s内完成。另外5名志愿者在扫描启动20s、40s、60s分别作左右60°运动,2s内完成。这5名志愿者在扫描结束后再模拟不配合患者在扫描启动后后作持续的任意运动。35例常规头部MRI检查出现头部运动伪影患者,行BLADE序列扫描(轴位T2WI、矢状位T1WI、轴位T1WI),对比常规扫描序列并评价BLADE技术对头部运动伪影纠正的作用。判断标准:以显示基底节区结构的清晰程度,行0～3级评分法。结果:设计为30°转动的10例健康志愿者,常规序列扫描,头部运动伪影均为2级及以上,影响诊断,占100%,采用BLADE技术后,头部运动伪影均降为2级以下,符合诊断要求,占100%,两者比较有显著差异(P<0.01)。设计为60°转动和持续运动的5例健康志愿者,常规序列扫描,头部运动伪影均为2级及以上,影响诊断,占100%,采用BLADE技术后,头部运动伪影降为2级以下者占70%和80%,两者比较有显著差异(P<0.01)。35例头部运动伪影中,2级及以上影响诊断的病例共26例,占74.3%。采用BLADE技术后,符合诊断的2级以下病例共32例,占91.4%,两者比较有显著差异(P<0.01)。结论:BLADE技术对常规头颅扫描中产生的运动伪影有明显的校正作用,可广泛用于不配合病人和儿童等易产生头部运动伪影的病人检查,提供清晰图像。

Purpose：To evaluate the application value of BLADE techniques in correcting head motion artifacts.Methods：Fifteen healthy volunteers were examined with routine cranial MRI examination by BLADE sequences（axial T2WI,sagittal T1WI,axial T1WI）.Ten of them were asked to rotate their heads at 20,40,60 s for 30° in 2s when under scanning.Another 5 of them were asked to rotate their heads at 20,40,60 s for 60° in 2s,or move their heads continuously when under scanning.Thirty-five patients with motion artifacts on routine head MRI were undergone BLADE sequences.The evaluation of the BLADE technology in correcting the head motion artifact effect was done.The clarity of the structure of basal ganglia（0-3 grade） was used as the criteria.Results：The head motion artifacts on regular sequences in 10 healthy volunteers with 30° rotation which were scored as grade 2 and above in 100%,while after BLADE was used,all cases of head motion artifacts were scored as below grade 2（100%）,and there was significant difference between the two methods（P0.01）.The head motion artifacts on regular sequences in 5 healthy volunteers with 60 ° rotation and continuous movement which were scored as grade 2 and above in 100%,while after BLADE was used,70% and 80% cases of head motion artifacts were scored as below grade 2（100%）,and there was significant difference between the two methods（P 0.01）.The head motion artifacts of 35 patients with routine MRI were scored as grade 2 and above in 26 cases（74.3%）,while after BLADE was used,32 cases（91.4%） of head motion artifacts were scored as below grade 2,and there was significant difference between the two methods（P0.01）.Conclusion：The Motion artifacts on routine MRI can be corrected by BLADE technology,it can be widely used in non-cooperative patients and children.