3.0T磁共振PWI、DTI及MRS在单侧大脑中动脉闭塞中的应用

发布时间：2018-01-23 13:35

本文关键词： 磁共振脑动脉闭塞灌注加权成像磁共振脑动脉闭塞弥散张量成像磁共振脑动脉闭塞磁共振波谱　出处：《山东大学》2014年博士论文　论文类型：学位论文

【摘要】：前言常规影像学检查(如CT、MRI)阴性的脑动脉闭塞或狭窄的脑血管病与脑卒中、白质疏松、脑萎缩、血管性痴呆有明显关系,采用有效的无创检查方法评价狭窄或闭塞动脉供血区脑组织的缺血损害程度尤为重要。本研究拟采用3.0T磁共振PWI、DTI及MRS研究常规影像学检查阴性的脑动脉闭塞或重度狭窄患者的脑组织血流灌注、弥散及代谢改变,为临床提供有效诊断信息。研究分为三部分,第一部分：3.0T磁共振PWI在单侧大脑中动脉闭塞的应用；第二部分：3.OT磁共振DTI在单侧大脑中动脉闭塞的应用；第三部分3.0T磁共振MRS在单侧大脑中动脉闭塞的应用。第一部分3.0T磁共振PWI在单侧大脑中动脉闭塞中的应用摘要目的：利用3.0T磁共振PWI对常规MRI脑实质无异常信号的单侧大脑中动脉闭塞或重度狭窄患者进行研究,以评价其供血区脑组织及远端脑白质灌注改变。方法：采用GE EXCITE Ⅱ3. OT双梯度超导磁共振仪,对脑实质无异常信号的34例单侧大脑中动脉M1段闭塞或重度狭窄("g75%)患者进行PWI研究,PWI采用T2*梯度回波EPI (T2*-GRE-EPI)成像序列,采用正交头线圈,扫描范围包括全脑,对比剂采用马根维显(Gd-DTPA),注射剂量0.2mmol/kg,流速4m1/s。采用GE functool4.2软件对受检者灌注数据进行后处理,对患、健侧放射冠区、颞叶皮质、丘脑、豆状核、内囊前肢、内囊后肢、大脑脚rCBF、rCBV、MTT、TTP进行分析,统计学方法利用SPSS13.0软件,采用配对t检验或秩和检验方法,按α=0.05水准,PO.05为差异具有统计学意义。结果：患侧放射冠区较镜像健侧平均MTT及TTP延长(P0.01),平均rCBF降低(P0.01),平均rCBV无统计学差异；患侧颞叶皮质较健侧镜像区平均MTT及TTP延长(P0.01),平均rCBF、rCBV无统计学差异；患侧豆状核较健侧镜像区平均TTP延长(P0.01),平均MTT、rCBF、rCBV无统计学差异；患侧内囊前肢及后肢较镜像健侧区平均TTP延长(P0.01),平均MTT、rCBF及rCBV无统计学差异；患侧丘脑、大脑脚MTT、rCBF、rCBV及TTP较镜像健侧无统计学差异。结论：利用MTT、rCBF、rCBV及TTP可快速、无创地评价常规MRI脑实质无异常的脑动脉闭塞或重度狭窄供血区脑组织血流灌注异常改变,其供血区远端脑白质无灌注异常发生,其中以MTT及TTP两参数最为敏感。目的：利用3.0T磁共振DTI对常规MRI脑实质无异常信号的单侧大脑中动脉Ml段闭塞或重度狭窄患者进行研究,以评价供血区及其远端脑组织弥散改变。方法：采用GE EXCITE Ⅱ3.0T双梯度超导磁共振仪,对脑实质无异常信号的34例单侧大脑中动脉闭塞或重度狭窄("g75%)患者进行DTI研究。DTI采用单次激励自旋回波EPI序列：(TR,6000ms;TE,90ms;NEX,4;thickness,5mm),扩散敏感梯度取15个方向,通过预实验b值取2200s/mm2。采用GE functool4.2软件对受检者DTI数据进行后处理,测量受检者患、健侧放射冠区、颞叶皮质、丘脑、豆状核、内囊前肢、内囊后肢、大脑脚及脑桥FA值、ADC值、平行弥散方向本征值λ1及垂直弥散方向本征值λ23。统计学方法利用SPSS13.0软件,采用配对t检验或秩和检验,按α=0.05水准,P0.05为差异具有统计学意义。结果：患侧放射冠区较镜像健侧FA值减小(P0.05),ADC、λ1及λ23值增大(P0.05)；患侧颞叶皮质λ23值较健侧增大(P0.05),而FA、ADC、λ1值无统计学差异；患侧豆状核较健侧λ23值增大(P0.05),而患、健侧FA、ADC及λ1值无统计学差异；患侧内囊前肢及后肢较健侧FA值减小(P0.05),λ23值增大(P0.05),而ADC及λ1值与健侧无统计学差异。患、健侧丘脑、大脑脚及脑桥FA、ADC、λ1及λ23值无统计学差异。结论：采用高b值DTI能够敏感探测常规MRI无异常信号的慢性脑动脉闭塞或重度狭窄供血区脑组织弥散异常,而缺血区远端脑白质无弥散异常改变。目的：利用3.0T磁共振MRS对常规MRI脑实质无异常信号的单侧大脑中动脉闭塞或重度狭窄患者进行研究,以评价供血区脑组织代谢改变。方法：采用GE EXCITE Ⅱ3.0T双梯度超导磁共振仪,对脑实质无异常信号的34例单侧大脑中动脉M1段闭塞或重度狭窄("g75%)患者进行MRS研究。MRS采用化学位移成像(Chemical Shift Imaging, CSI)进行多体素采集,点解析波谱(Point Resolved Spectroscopy, PRESS)序列扫描,TR1500ms, TE135ms,采集时间5.6min。应用GE EXCITE Ⅱ3.0T MR仪自带MRS分析软件,测量患、健侧放射冠区、丘脑、豆状核NAA、Cr、Cho及NAA/Cho、NAA/Cr、Cho/Cr值,并观察Lac峰。统计学方法利用SPSS13.0软件,采用配对t检验或秩和检验,按α=0.05水准,P0.05为差异有统计学意义。结果：患侧放射冠区较镜像健侧平均NAA、Cr、NAA/Cr及NAA/Cho减小(P0.01), Cho及Cho/Cr增大(P0.05)；患侧丘脑平均Cho、NAA、Cr、NAA/Cr、 NAA/Cho及Cho/Cr与镜像健侧无统计学差异；患侧豆状核较镜像健侧平均NAA、NAA/Cho降低降低(P0.05), Cho及Cho/Cr升高(P0.05),患侧豆状核Cr及NAA/Cr与镜像健侧无统计学差异,所有患者患侧各测量部位未观察到Lac峰。结论：MRS可敏感检测慢性脑动脉重度狭窄或闭塞所致供血区脑组织的代谢改变,弥补了常规MRI的不足。
[Abstract]:The conventional imaging (such as CT, MRI) negative cerebral artery occlusion or stenosis of cerebral vascular disease and stroke, leukoaraiosis, cerebral atrophy was related to vascular dementia, the effective evaluation of non invasive examination methods of artery stenosis or occlusion of cerebral ischemia, the extent of damage is particularly important. The study of 3.0T magnetic resonance PWI, DTI and MRS on routine examination negative imaging of cerebral artery occlusion or severe stenosis in patients with cerebral perfusion, diffusion and metabolic changes, to provide effective information for clinical diagnosis. The research is divided into three parts, the first part: occlusion by 3.0T magnetic resonance PWI in unilateral cerebral artery in the second part; occlusion by 3.OT magnetic resonance DTI artery in unilateral middle cerebral artery in the brain; the application of unilateral occlusion of the third part of the 3.0T magnetic resonance MRS.
The application of 3.0T MRI PWI in unilateral middle cerebral artery occlusion in the first part
Objective: To investigate the changes of white matter perfusion in blood supply area and distal brain by using 3.0T magnetic resonance PWI in patients with unilateral middle cerebral artery occlusion or severe stenosis without abnormal signal in routine MRI.
Methods: the GE EXCITE II 3. OT dual gradientsuperconducting MRI, 34 cases of unilateral brain no abnormal signal of brain parenchyma in M1 segment artery occlusion or severe stenosis (g75%) patients with PWI research, PWI by T2* EPI (T2*-GRE-EPI) gradient echo imaging sequence, orthogonal head coil, including full scan range the brain, by contrast agent Magnevist injection (Gd-DTPA), 0.2mmol/kg, 4m1/s. using GE functool4.2 software flow for subjects with perfusion data postprocessing, the patients with contralateral corona radiata, temporal lobe cortex, thalamus, lentiform nucleus, anterior limb of the internal capsule, posterior limb of the internal capsule, cerebral peduncle rCBF, rCBV, MTT TTP, analysis, statistical methods using SPSS13.0 software, using the paired t test or rank sum test method, according to a =0.05 level for PO.05, the difference was statistically significant.
Results: the ipsilateral contralateral mirror regions than radiata average MTT and TTP extension (P0.01), a lower average rCBF (P0.01), there was no significant difference in the average rCBV; the ipsilateral temporal lobe cortex than the healthy side mirror area and average MTT TTP extension (P0.01), average rCBF, rCBV had no statistical difference; the average side TTP the lentiform nucleus than the contralateral mirror area (P0.01), prolong the average MTT, rCBF, rCBV had no significant difference; the average TTP lateral anterior limb of the internal capsule and hindlimb compared with contralateral mirror extension (P0.01), average MTT, no significant difference between rCBF and rCBV; the ipsilateral thalamus, cerebral peduncle MTT, rCBF, no significant difference rCBV and TTP compared with the contralateral mirror.
Conclusion: the use of MTT, rCBF, rCBV and TTP can be rapid, noninvasive evaluation of conventional MRI brain parenchyma abnormal cerebral artery occlusion or severe stenosis of the blood supply area of cerebral perfusion abnormalities, the blood supply area of the distal white matter no perfusion abnormalities occur, with MTT and TTP two was the most sensitive parameter.
Objective: To study the diffusion changes of blood supply area and its distal brain tissue by using 3.0T magnetic resonance DTI in patients with Ml segment occlusion or severe stenosis of the middle cerebral artery in routine MRI without abnormal signal.
Methods: the GE EXCITE II 3.0T dual gradientsuperconducting MRI, 34 cases of unilateral brain no abnormal signal of brain parenchyma in arterial occlusion or severe stenosis (g75%) of DTI.DTI by using single excitation spin echo EPI sequence were: (TR, 6000ms; TE, 90ms; NEX, 4; thickness. 5mm, 15) diffusion sensitive gradient direction, 2200s/mm2. of subjects DTI data postprocessing using GE functool4.2 software through the pre experiment, b value were measured with contralateral corona radiata, temporal lobe cortex, thalamus, lentiform nucleus, anterior limb of the internal capsule, posterior limb of the internal capsule, cerebral peduncle and pons FA value, ADC value, parallel diffusion direction eigenvalue lambda 1 and vertical diffusion direction of the eigenvalues lambda 23. statistical methods by SPSS13.0 software, using the paired t test or rank sum test, according to a =0.05 level for P0.05, the difference was statistically significant.
Results: the ipsilateral contralateral mirror regions than radiata FA decreased (P0.05), ADC, and lambda 1 lambda 23 increased (P0.05); the ipsilateral temporal lobe cortex compared with the contralateral lambda 23 increase (P0.05), FA, ADC, a value of 1. There were no significant differences in the ipsilateral lentiform nucleus; compared with the contralateral lambda 23 (P0.05), and the value increases with the contralateral FA, ADC value and lambda 1 no significant difference; the ipsilateral anterior limb and limb than contralateral FA decreased (P0.05), a 23 increase value (P0.05), and no significant difference between ADC and lambda 1 value and the healthy side. Patients with contralateral thalamus and pons, cerebral peduncle FA, ADC, lambda 1 lambda 23 values and no statistical differences.
Conclusion: high b value DTI can be used to detect abnormal diffusion of brain tissue in chronic cerebral artery occlusion or severe stenosis of normal MRI without abnormal signal, but there is no abnormal change of white matter in ischemic area.
Objective: To study the metabolic changes of cerebral tissue in blood supply area by using 3.0T magnetic resonance MRS in patients with unilateral middle cerebral artery occlusion or severe stenosis without abnormal signal in routine MRI.
Methods: the GE EXCITE II 3.0T dual gradientsuperconducting MRI, 34 cases of unilateral brain no abnormal signal of brain parenchyma in M1 segment artery occlusion or severe stenosis (g75%) of MRS.MRS were analyzed by chemical shift imaging (Chemical Shift Imaging, CSI) multi voxel point resolved spectroscopy (Point Resolved Spectroscopy, PRESS TR1500ms, TE135ms) sequence, MRS analysis software, using GE EXCITE 5.6min. with the acquisition time measuring instrument with MR II 3.0T, thalamus contralateral corona radiata, lenticula, NAA, Cr, Cho and NAA/Cho, NAA, /Cr, Cho/Cr, and observe the Lac statistical method using SPSS13.0 peak. The software, using the paired t test or rank sum test, according to a =0.05 level of P0.05, the difference was statistically significant.
Results: the ipsilateral than the contralateral mirror radiata district average NAA, Cr, NAA/Cr and NAA/Cho decreased (P0.01), Cho and Cho/Cr increased (P0.05); the ipsilateral thalamus was Cho, NAA, Cr, NAA/Cr, NAA/Cho and Cho/Cr had no significant difference with the contralateral mirror; the ipsilateral lentiform nucleus than the contralateral mirror the average NAA, NAA/Cho decreased (P0.05), Cho and Cho/Cr increased (P0.05), ipsilateral lentiform nucleus Cr and NAA/Cr and the contralateral mirror had no statistical difference, all patients with each measurement site was observed Lac peaks.
Conclusion: MRS can detect the metabolic changes of brain tissue in the blood supply area caused by chronic severe cerebral artery stenosis or occlusion, and make up for the deficiency of conventional MRI.

【学位授予单位】：山东大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：R743;R445.2

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