摘要
目的与磁共振成像(magnetic resonance imaging,MRI)传统扩散加权成像(diffusion weighted imaging,DWI)对比,探讨MRI多层并采扩散峰度成像(multi-band EPI diffusion kurtosis imaging,m-DKI)界定急性缺血性卒中梗死核心的准确性。方法选择在发病3~8 h进行MRI检查的急性缺血性卒中患者,所有患者经灌注加权成像(perfusion weighted imaging,PWI)判定不存在缺血半暗带,没有接受静脉溶栓/动脉取栓治疗。基线扫描时加入传统DWI以及m-DKI序列,并在患者发病亚急性期([7±1)d]复查MRI扫描,利用Mricron软件分别对基线MRI检查表观扩散系数(apparent diffusion coefficient,ADC)图,平均扩散峰度(mean kurtosis,MK)图以及复查MRI T_1加权成像(T_1 weighted imaging,T_1WI)责任病灶体积进行测量,分别计算ADC图、MK图与T_1WI责任病灶体积的差值,并进行比较。结果入组的19例患者,1例患者DWI显示缺血病灶,但MK图及复查MRI均未见责任病灶;1例患者病灶位于基底节区附近,影响MK图责任病灶观察及测量。余17例患者MK图显示责任病灶的体积与亚急性期T_1WI责任病灶体积的差值为(0.25±0.37),而ADC图显示责任病灶的体积与亚急性期T_1WI体积的差值为(0.73±0.72)(t=3.968,P=0.001)。MK图责任病灶的体积更接近T_1WI的体积。结论与传统DWI相比,基线m-DKI显示责任病灶的体积更接近复查T_1WI的体积,对最终梗死核心的界定更为准确。
Objective To compare the accuracy of multi-band EPI diffusion kurtosis imaging(m-DKI) with traditional diffusion weighted imaging(DWI) in identifying infarct lesion in acute ischemic stroke patients. Methods The patients with suspected acute ischemic stroke who underwent MR examination(3-8 h after onset) were admitted into this study. The MR results showed these patients had no ischemic penumbra. These patients didn't receive intravenous thrombolytic therapy or thromboembolectomy. The baseline MR included conventional DWI and m-DKI sequence,the follow-up MR of all the patients were carried out in(7±1) days after onset of stroke. The infarct lesion volume of baseline MRI apparent diffusion coefficient(ADC) map,mean kurtosis(MK) map and follow-up MRI T_1 weighted imaging(T_1WI) were measured with Mricron. The lesion volume differences between ADC map and T_1 WI,and between MK map and T_1 WI were calculated. Then the percentage of difference in the volume of lesion on T_1 WI was calculated and compared. Results A total of 19 patients were admitted into this study. The baseline DWI of one patientshowed ischemic tissue,though the baseline m-DKI and follow-up T_1 WI didn't show infarct lesion. The infarct lesion of one patient was located around basal ganglia,which added difficulty to observe and measure the lesion on MK map. The D-value percentage of the volume of lesions of the left 17 patients between MK map and T_1 WI was(0.25±0.37),while the D-value percentage between ADC map and T_1 WI was(0.73±0.72)(t =3.968,P=0.001). The volumes of lesion by MK map was much closer to the real size of T_1 WI. Conclusion In the identification of the final infarct size in acute ischemic stroke,the volume measurement by baseline m-DKI on acute-phase is more reliable than that of conventional DWI.
出处
《中国卒中杂志》
2016年第3期184-190,共7页
Chinese Journal of Stroke
基金
国家自然科学基金急性脑梗死责任斑块的组织学及磁共振成像评估研究中美合作项目(812111546)
"十二五"国家科技支撑计划项目(2011BA108B09)
关键词
卒中
扩散峰度成像
梗死核心
Stroke
Diffusion kurtosis imaging
Infarct core