Influence of the site of arterial occlusion on multiple baseline hemodynamic MRI parameters and post-thrombolytic recanalization in acute stroke

In this prospective MRI study, we evaluated the impact of the site of occlusion on multiple baseline perfusion parameters and subsequent recanalization in 49 stroke patients who were given intravenous tissue plasminogen activator (tPA). Pretreatment magnetic resonance angiography (MRA) revealed an arterial occlusion in 47 patients: (1) internal carotid artery (ICA) + M1 middle cerebral artery (MCA) occlusion (n=12); (2) M1 MCA occlusion (n=19); (3) M2 MCA, distal branches of the MCA and anterior cerebral artery (ACA) occlusion (n=16). Patients with ICA occlusion had significantly larger DWI, PWI and mismatch lesion volume on pretreatment MRI compared to patients with other sites of occlusion. The differences in cerebral blood flow (CBF) and peak height were significantly higher in patients with ICA occlusion compared to patients with other sites of occlusion (P=0.03 and P=0.04, respectively). Day 1 MRA showed recanalization in 28 patients (60%). The rate of recanalization was significantly different depending on the site of occlusion: 33% in ICA + M1 MCA occlusion, 63% in M1 MCA occlusion and 81% in either M2 MCA, distal branches of the MCA or ACA occlusion (P=0.002). Our data suggest that CBF and peak height are the most relevant MRI parameters to assess the severity of hemodynamic impairment in regard to the site of occlusion.     

Investigation of stroke in sickle cell disease by1H nuclear magnetic resonance spectroscopy

Summary Localized proton nuclear magnetic resonance spectroscopy (MRS), obtained with stimulated echo and spin echo sequences, MR imaging (MRI) and MR angiography (MRA) were used to study the brain in 13 children and adolescents with sickle cell disease. Regions of interest (ROI) studied by MRS included regions appearing normal on MRI as well as regions showing complications of sickle cell disease, including focal deep white matter areas of high signal intensity (deep white matter ischemia, DWMI) seen on long TR images, focal atrophic brain areas, and infarcts. The findings in these studies are summarized as follows: Normal-appearing regions on MRI have normal MRS. In ROI including small areas of DWMI, lactate elevation was not detected, but the levels ofN-acetyl-aspartate (NAA) appeared slightly elevated. In areas of DWMI 1–2 cm in size, reduced blood flow could be seen on MRA and lactate elevation could be detected with MRS. When blood flow to a DWMI region was normal, NAA was reduced and there was little lactate elevation, as cell death had already occurred. ROI consisting of atrophic tissue had reduced NAA levels but total creatine levels were not changed. Sometimes lipids, presumably from broken cell membrane, could be detected. In regions of past massive stroke, all metabolites were absent except for small amounts of lactate or lipids.     

Long-term follow-up of asymptomatic patients with major artery occlusion: rate of symptomatic change and evaluation of cerebral hemodynamics

BACKGROUND AND PURPOSE: The natural history of asymptomatic major cerebral artery occlusive disease is unclear. Rate of symptomatic change, appearance of new lesions on MR images, and cerebral hemodynamics were analyzed for patients with asymptomatic major cerebral artery occlusion. METHODS: This prospective study included asymptomatic patients who had occlusive disease between 1992 and 1995. MR imaging and MR angiography were used to detect internal carotid artery (ICA) or middle cerebral artery (MCA) occlusion in 3965 neurologically asymptomatic patients and for follow-up of affected patients for 67 to 105 months (mean, 79 months). Regional cerebral blood flow and cerebrovascular reserve capacity were examined by xenon-enhanced CT at rest and after the administration of acetazolamide, respectively. RESULTS: Eighteen patients had MCA occlusion and 17 had ICA occlusion. During the follow-up period, five patients became symptomatic (four with MCA occlusion and one with ICA occlusion), with no significant difference (P = .332) in the rate of symptomatic change. Among these five patients, new infarction occurred on the ipsilateral side in three patients, contralateral side in one, and bilateral sides in one. New stenotic or occlusive changes occurred in three patients. The patients were divided into groups: group A, without new lesions on MR images (n = 23), and group B, with new lesions (n = 12). There was no significant difference in regional cerebral blood flow value between groups A and B in the whole hemisphere, anterior cerebral artery territory, or MCA territory. There was a significant difference in cerebrovascular reserve capacity between groups A and B between the affected side (P = .00051 and P = .00068, respectively) and the contralateral side (P = .00101 and P = .00115, respectively) for the whole hemisphere and MCA territory, and the difference was more severe on the affected side in both regions. CONCLUSION: These pilot data suggest that asymptomatic MCA occlusion has a worse prognosis than does ICA occlusion. Silent events are common bilaterally. This may be because of hemodynamic factors or perhaps MCA occlusion is a marker for a more progressive type of atherosclerosis. A prospective study involving assessment of hemodynamics and baseline stroke risk factors in patients with MCA occlusion is indicated.     

磁共振脑血管血流分析的临床应用——脑血栓、脑缺血与正常组对比研究

目的：测定脑血栓、脑缺血患者和正常人的颅内动脉血流，为临床提供进一步的诊断资料。材料和方法：应用ＭＲ血流分析技术，对４２例大脑中动脉（ＭＣＡ）、颅内动脉（ＩＣＡ）及基底动脉（ＢＡ）血流进行了测量与分析。结果：（１）ＭＣＡ脑梗塞组血流速度峰值增高而平均血流量值降低；脑缺血组血流速度峰值增高或正常而平均血流量值正常或降低，二者必居其一；正常组之ＭＲ血流分析无异常。（２）ＩＣＡ和ＢＡ二者均未见明显异常。结论：推测ＭＲ脑血流分析技术在预测中风方面可能是有效的检测手段。     

Hyperacute ischemic stroke: middle cerebral artery susceptibility sign at echo-planar gradient-echo MR imaging

PURPOSE: To evaluate the accuracy of echo-planar T2*-weighted magnetic resonance (MR) sequences in detection of acute middle cerebral artery (MCA) or internal carotid artery (ICA) thrombotic occlusion. MATERIALS AND METHODS: Forty-two consecutive patients with stroke involving the MCA territory underwent MR imaging within 6 hours after clinical onset. MR examination included echo-planar T2*-weighted, diffusion-weighted (DW), and perfusion-weighted (PW) imaging and MR angiography. Presence or absence of the susceptibility sign on echo-planar T2*-weighted images, which is indicative of acute thrombotic occlusion involving MCA or ICA, was assessed in consensus by two observers blinded to clinical information and other MR imaging data. Differences in lesion volume on DW and PW images between patients with and those without the susceptibility sign were evaluated with the Mann-Whitney test. P <.05 was considered to indicate a significant difference. RESULTS: Thirty patients (71%) had a positive susceptibility sign that correlated with MCA or ICA occlusion at MR angiography in all cases (sensitivity, 83%; specificity, 100%). Mean lesion volume on PW images was higher in patients with a positive susceptibility sign (P =.01), but no significant differences were found in mean lesion volume on DW images. Cases in which the susceptibility sign was identified proximal to MCA divisional bifurcation (27 patients) showed a mean perfusion deficit of 83.9% of the total MCA territory (range, 50%-100%). CONCLUSION: Presence of the susceptibility sign proximal to MCA bifurcation provides fast and accurate detection of acute proximal MCA or ICA thrombotic occlusion.     

多期相超短回波四维MRA在评估颅内血管狭窄中的应用价值

目的:探讨多期相超短回波四维磁共振血管成像(mUTE 4D MRA)在评估颅内血管狭窄中的应用价值.方法:前瞻性收集59例脑血管病患者的临床及影像资料,受试者均先行3D时间飞跃法MR血管成像(3D TOF MRA)和mUTE 4D MRA扫描,然后在同一天行CT血管成像(CTA)检查.由2位神经影像医师采用双盲法对血管...     

Solitaire AB型支架用于急性脑动脉闭塞取栓术31例

目的探讨Solitaire AB型支架用于急性脑动脉闭塞动脉取栓术的效果及安全性。方法 2010年5月至2011年5月采用Solitaire AB型支架用于急性脑动脉闭塞的动脉取栓术,共31例,其中颈内动脉闭塞6例,大脑中动脉闭塞12例,基底动脉闭塞9例,合并大脑中动脉及基底动脉闭塞1例,颈内动脉末段合并大脑中动脉闭塞3例。回顾性分析其即时取栓效果,术后出血情况,并比较其随访90 d时的MRS评分情况。结果大脑中动脉和基底动脉闭塞患者均成功再通,颈内动脉有6例(6/9)获再通。12例患者因为再通后仍存在管腔狭窄而放置支架。术后颅内出血4例(12.9%),死亡8例(25.8%)。在死亡患者中,5例责任动脉在颈内动脉,3例在基底动脉。从发病到获得再通时间超过8 h者8例,其中死亡2例,均为颈内动脉闭塞患者。90 d随访患者中,出院MRS评分预后良好(<2)的有15例(48.4%)。结论用Solitaire AB型支架进行动脉取栓对于大脑中动脉及基底动脉闭塞患者能获得较高的再通率,改善临床结局,但对颈内动脉闭塞患者效果不理想,再通率低,死亡率高。     

MR动脉血质子自旋标记与波谱成像在颈内动脉系统狭窄或闭塞的应用研究

目的 探讨MR动脉血质子自旋标记(ASL)与氢质子磁共振波谱成像(1H-MRS)在颈动脉系统狭窄或闭塞的应用价值. 资料与方法 28例单侧颈内动脉(ICA)/大脑中动脉(MCA)重度狭窄或闭塞患者行ASL 和1H-MRS检查.对ASL后处理的相对脑血流量(CBF) 图进行定性和定量分析;对1H-MRS测量病变侧和对侧脑组织的氮-乙酰天门冬氨酸(NAA)、胆碱(Cho)、肌酸(Cr)的波峰下面积,比较两侧各代谢物峰下面积比值(NAA/Cho、NAA/Cr、Cho/Cr)的差异,并观察是否出现乳酸(Lac)峰. 结果 28例CBF图显示18例病变侧灌注较对侧降低,10例未见明显异常;1H-MRS显示病变侧的NAA/Cho、NAA/Cr低于对侧,差异有统计学意义(P<0.01),Cho/Cr高于对侧,差异有统计学意义(P<0.01),3例于病变侧检测到Lac峰. 结论 ASL 能够早期发现颈动脉系统狭窄或闭塞患者的CBF改变,1H-MRS能够显示缺血脑组织的代谢异常.     

MRI and <Superscript>1</Superscript>H MRS findings in Smith-Lemli-Opitz syndrome

Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disorder characterized by a defect in cholesterol biosynthesis, associated with mental retardation and multisystem structural abnormalities. This study investigated the prevalence of congenital CNS abnormalities by MRI in a large series of patients with SLOS and the correlation of the clinical and biochemical findings with the results of MRI and ¹H MRS. Eighteen patients were studied; all underwent MRI of the brain, and 16 had ¹H MRS of the cerebral white matter. The ratios choline:NAA, lipid:NAA, and lipid:choline metabolite were found to be correlated with the clinical degree of disease severity, serum total sterol ratios (cholesterol/cholesterol + 7-dehydrocholesterol + 8-dehydrocholesterol) and in two cases with the effect of cholesterol therapy. Abnormal CNS findings were noted in five patients, including callosal abnormalities (n=4), Dandy-Walker variant (n=1), and arachnoid cyst (n=1). Holoprosencephaly was noted in one patient with a prevalence of 6%. Choline:NAA was elevated in seven patients. There was a statistically significant positive correlation between the lipid:choline ratio and the serum cholesterol precursor, 8-dehydrocholesterol. In two patients ¹H MRS demonstrated abnormally elevated lipids prior to cholesterol therapy, which improved on therapy. The use of MRI and ¹H MRS is an effective way to demonstrate brain structural abnormalities in patients with SLOS and may prove to be an effective method for the assessment of the effects of cholesterol replacement therapy in the brain.     

Redistribution of cerebropetal blood flow in patients with carotid artery stenosis measured non-invasively with fast cine phase contrast MR angiography

The purpose was to evaluate the blood flow redistribution in the neck vessels of patients with internal carotid artery (ICA) stenosis. Eighty-six patients with ICA stenosis underwent contrast-enhanced magnetic resonance angiography (CEMRA) and fast 2D phase contrast (2D-PC) sequence to measure the mean blood flow (MBF) of ICA, basilar artery (BA) and middle cerebral artery (MCA). CEMRA revealed 53 severe stenoses, 45 moderate stenoses and 3 occluded vessels. Patients with a unilateral severe ICA stenosis had a significantly reduced MBF of the ICA compared to the control group; the MBF reduction of the severely stenosed ICA was less conspicuous if associated with a controlateral severe stenosis. The MBF of the BA increased significantly in the presence of the bilateral severe ICA stenosis and in the ICA occlusion. The MBF of the MCA was unchanged in the presence of various degrees of ICA stenosis. Measurement of MBF with fast PC MRA permits cerebropethal blood flow assessment and gives additional information in grading ICA stenosis. The reduced MBF of a severe ICA stenosis has to be considered with caution since it depends also on the status of the controlateral ICA and may be considered a confident parameter only in case of unilateral carotid stenosis.     

Poststenotic flow and intracranial hemodynamics in patients with carotid stenosis: transoral carotid ultrasonography study

BACKGROUND AND PURPOSE: In severe carotid stenosis, blood supply via the poststenotic internal carotid artery (ICA) and collateral pathways determine cerebral perfusion. We investigated whether poststenotic flow on transoral carotid ultrasonography (TOCU) is predictive of cerebral hemodynamics. METHODS: Eighty-eight patients with unilateral carotid stenosis underwent TOCU to analyze blood flow velocity and poststenotic diameter of the extracranial ICA. Intracranial collaterals and cerebral hemodynamics were assessed with selective angiography and single photon emission CT. RESULTS: Poststenotic diameter (P <.0001) and velocities (peak systolic velocity [PSV], time-averaged mean velocity [TMV], end-diastolic velocity [EDV]; all P < or = .009) decreased with stenotic severity. Poststenotic diameter was correlated with PSV (r=0.36, P=.0005), EDV (r=0.32, P=.002), and TMV (r=0.39, P=.0001). Poststenotic flow was significantly lower with collateral pathways than without pathways (P < or = .02) and significantly decreased as the number of the collaterals increased (P <.0001). Flow <5 mL/s indicated collaterals (81% sensitivity, 80% specificity). When flow was <5 mL/s, the asymmetry index in the middle cerebral artery (MCA) territory was significantly low during rest (P=.003) and after acetazolamide challenge (P=.006). Poststenotic flow velocity was associated with baseline (P=.007) and postacetazolamide (P=.0009) MCA asymmetry indexes. CONCLUSION: Poststenotic ICA flow measured with TOCU reflects collateral flow and cerebral hemodynamics in patients with severe carotid stenosis. This technique may provide new parameters for screening patients with hemodynamically significant carotid stenosis.     

Evaluation of brain metabolism in steno-occlusive carotid artery disease by proton MR spectroscopy: a correlative study with oxygen metabolism by PET.

Carotid occlusive diseases may cause ischemic changes in both the gray matter and the white matter as a result of hemodynamic compromise. To validate the use of proton magnetic resonance spectroscopy (MRS) in evaluating the carotid occlusive diseases, we compared changes in peaks of choline, in the sum of creatine and phosphocreatine, and in N-acetyl-aspartate (NAA) of the white matter with cortical oxygen metabolism measured by PET. METHODS: Eleven patients with unilateral steno-occlusive carotid artery disease underwent PET and MRS. Ten age-matched healthy volunteers underwent MRS. No subjects had cortical infarction. MRS was performed bilaterally in the centrum semiovale. Regional blood flow, regional metabolic rate of oxygen (rCMRO2), and regional oxygen extraction fraction (rOEF) of the cerebral cortex were measured by the steady-state method with 15O gas. RESULTS: The asymmetry index of the ratio of NAA to the sum of creatine and phosphocreatine (NAA/Cr) correlated positively with the asymmetry index of rCMRO2 (r = 0.77; P < 0.01). Because rCMRO2 is a marker of tissue viability, the NAA/Cr of the centrum semiovale may reflect viable neuronal cells. The asymmetry index of the ratio of choline to the sum of creatine and phosphocreatine (Cho/Cr) showed a significant positive correlation with the asymmetry index of rOEF (r = 0.65; P < 0.05). All but 1 patient with an increased Cho/Cr (>1.03) showed an increase in rOEF of the ipsilateral cortex (>0.56). This finding may indicate membrane damage caused by ischemia, because the centrum semiovale is the deep watershed zone. CONCLUSION: The metabolic changes in the centrum semiovale detected by proton MRS reflect a hemodynamically compromised state and are useful in evaluating tissue viability.     

成人型moya moya病的MR和MRA诊断(附6例分析)

目的：分析成人型moyamoya病的MRI和MRA影像特征。方法：回顾性分析6例经DSA证实的成人moyamoya病的MRI及MRA影像资料，采用GE1.5T超导型MR扫描系统行SE、FSE序旬MRI和三维时间飞跃法MRA。结果：成人型moyamoya病主要表现为多发腔隙性梗塞、脑萎缩，或并发脑实质出血、蛛网膜下腔出血。MRI显示闭塞的颅底大血管流空效应消失，兵脑和基底节区侧支循环流空信号增多，脑实质缺血或出血改变。MRA直接显示狭窄或闭塞的预内动脉（ICA）、大脑中动脉（MCA）、大脑前动脉（ACA）及侧支血管网。与DSA对比，MRA能够准确地显示闭塞或狭窄的大血管和代偿的不成形的弯延扭曲的侧支血管网。结论：MRI和MRA相结合可正确诊断moyamoya病，MRA是一种无创、短时、成功率和准确性高的检查方法，也可用于筛选可疑颅内动脉狭窄或闭塞的患者，避免或减少血管造影的次数。     

MRA评估TIA患者脑血流量变化

目的 联合应用电影相位对比磁共振血管成像(cine PC MRA)、三维时间飞跃磁共振血管成像(3D TOF MRA)和三维对比增强磁共振血管成像 (3D CE -MRA)评估一过性脑缺血发作(TIA)患者全脑血流量和供血动脉病变对血流量的影响.资料与方法 采用MRA对41例TIA患者、30例正常人和30例脑梗死者的全脑血流量和脑供血动脉进行对照研究.结果 30例无脑动脉严重狭窄的TIA患者与30例正常人之间的全脑血流量差异无统计学意义(P=0.101).有颈内动脉(ICA)/椎-基底动脉(V-BA)严重狭窄的11例TIA患者与18例脑梗死患者的全脑血流量差异无统计学意义(P=0.150),但脑梗死患者合并大脑前动脉(ACA)、大脑中动脉(MCA)和大脑后动脉(PCA)狭窄或闭塞的概率较大(P=0.018).结论 无脑动脉严重狭窄的TIA患者与正常人之间的全脑血流量无明显差异,而有脑动脉严重狭窄的TIA脑梗死患者的全脑血流量无明显差异.     

SWI 在超急性大面积脑梗死中的应用价值

目的：探讨磁敏感加权成像(SWI)在超急性大面积脑梗死中的应用价值。方法连续纳入40例大脑中动脉供血区超急性大面积脑梗死患者,扫描序列包括常规 MRI、DWI、MRA 及 SWI,由2位高年资神经影像医师分析 MRI 图像并记录结果,比较SWI 和常规序列大脑中动脉血栓检出数及 MRA 显示动脉狭窄或闭塞数,比较 SWI 和常规序列显示血栓长度及梗死区静脉增多情况。结果SWI 血栓检出数与常规 MRI 比较有显著差异(23 vs 12,χ2=6.146,P =0.013),与 MRA 比较无显著差异(23 vs 24,χ2=0.052,P =0.820)。2例患者 SWI 同时观察到大脑中动脉主干及分支血栓。SWI 显示血栓长度与常规序列比较有显著差异(25.7 mm±9.4 mm vs 14.6 mm±8.5 mm,t=14.395,P =0.000),SWI 显示脑梗死区静脉增多病例数与常规序列比较有显著差异(21 vs 12,χ2=4.178,P =0.041)。结论SWI 在超急性大面积脑梗死中有较大应用价值。     

Time-resolved contrast-enhanced MR angiography of intracranial lesions

PURPOSE: To determine if contrast-enhanced (CE) MRI of intracranial lesions benefits from time-resolved MR angiography (MRA) during contrast agent injection. MATERIALS AND METHODS: For 126 patients with suspected intracranial lesions undergoing routine CE MRI at 3.0T (N = 88) or 1.5T (N = 38), time-resolved CE MRA (three-dimensional [3D] time-resolved imaging of contrast kinetics [TRICKS]) was performed during injection of the routine gadolinium (Gd) dose of 0.1 mmol/kg. Time to peak (TTP) enhancement of lesions as well as time to internal carotid artery (ICA), middle cerebral artery (MCA), superior sagittal sinus (SSS), and jugular vein enhancement were measured. Source and maximum intensity projection (MIP) images were reviewed to delineate the spatial relationship of lesions and the vasculature. RESULTS: In 61 patients (48%), additional important findings were detected on time-resolved MRA that were not seen on the routine CE protocol, including aneurysms (N = 6), arteriovenous malformations (N = 7), ICA stenoses (N = 2), vascular anomalies (N = 18), and relationships between lesions and vessels (N = 28). In addition, tumor TTP correlated with glioma grade (r = 0.87) and discriminated epithelial from nonepithelial meningiomas (P = 2.6 x 10(-5)). MRA added eight minutes to the total exam time. CONCLUSION: Time-resolved MRA performed during contrast agent injection adds information to the routine brain CE MRI examination of intracranial lesions with only a small time penalty and no additional risk to the patient.     

Proton magnetic resonance spectroscopy of human brain: applications to normal white matter, chronic infarction, and MRI white matter signal hyperintensities.

A modified ISIS method, for image-selected localized proton magnetic resonance spectroscopy (1H MRS), was used to determine the ratios and T2 relaxation times of proton metabolites in normal subjects and in patients with chronic infarction and MRI white matter signal hyperintensities (WMSH). First, in patients with cerebral infarctions, increased concentrations of lactate were found in the majority of patients, and N-acetyl aspartate (NAA) was reduced to a significantly greater extent than choline (Cho) or creatine (Cre). For TE = 270 ms, the raw ratios of Cho/NAA, Cre/NAA, and Lac/NAA were significantly (P less than 0.05) increased from 0.23 +/- 0.02 (mean +/- SE), 0.20 +/- 0.01, and 0.05 +/- 0.01, respectively in the normal group to 0.39 +/- 0.08, 0.37 +/- 0.05, and 0.48 +/- 0.15 in the stroke group. Also, the T2 relaxation time of creatine was significantly (P = 0.007) increased from 136 ms in normal white matter to 171 ms in cerebral infarcts. Second, in patients with WMSH, no significant change of the proton metabolite concentrations could be detected with the exception of the choline which was significantly (P = 0.003) altered. The Cho/NAA ratio, after T2 and excitation profile correction, increased from 0.47 +/- 0.02 in the normal group to 0.64 +/- 0.05 in the WMSH group. Third, in normal white matter, the concentration of N-acetyl aspartate, choline, and lactate was estimated to 11.5, 2.0, and 0.6 mM, respectively, by assuming a total creatine concentration of 10 mM.     

Symptomatic carotid artery occlusion: flow territories of major brain-feeding arteries

PURPOSE: To prospectively investigate the extent of flow territories of the contralateral internal carotid artery (ICA) and vertebrobasilar arteries in patients with symptomatic ICA occlusion. MATERIALS AND METHODS: Ethics committee approval and informed consent were obtained. Flow territory mapping of the ICA contralateral to the occluded ICA and mapping of the vertebrobasilar arteries were performed by using selective arterial spin-labeling magnetic resonance imaging in 23 functionally independent patients (22 men, one woman; mean age, 58 years +/- 8 [standard deviation]) with symptomatic ICA occlusion. The control group consisted of 68 subjects (57 men, 11 women; mean age, 59 years +/- 9) without hemodynamically significant ICA obstruction. Voxel-based chi(2) testing with Bonferroni correction was performed to analyze significant differences in the extent of the flow territories. RESULTS: Flow territory maps in patients with symptomatic ICA occlusion showed significant differences in the flow territories of the contralateral ICA and vertebrobasilar arteries compared with those in control subjects (P < .05). CONCLUSION: In functionally independent patients with symptomatic ICA occlusion, the middle cerebral artery flow territory ipsilateral to the occluded ICA is mainly supplied by the vertebrobasilar arteries, whereas the anterior cerebral artery flow territory on the occluded side is mainly supplied by the contralateral ICA.     

大脑中动脉狭窄相关的脑梗塞20例临床分析

目的：分析了２０例大脑中动脉（ＭＣＡ）狭窄相关的脑梗塞患者的临床中风模式与神经影像（ＣＴ／ＭＲＩ）特点。方法；对经颅多普勒超声（ＴＣＤ）等确诊的２０例ＭＣＡ狭窄的脑梗塞患者进行临床与神经影像的对比分析，结果：２０例中，腔隙综合征１０例（５０％），ＣＴ／ＭＲＩ显示无病灶２例（１０％），基底节和内囊腔隙性脑梗塞８例（４０％）非腔隙综合征１０例（５０％），ＣＴ／ＭＲＩ显示ＭＣＡ皮层无梗塞９例（４５％），     

Axonal damage in the spinal cord of multiple sclerosis patients detected by magnetic resonance spectroscopy.

Axonal damage is a major factor contributing to permanent disability in patients with multiple sclerosis (MS); it has been extensively investigated in the brain using magnetic resonance spectroscopy (MRS). In this study, MRS was used to investigate the degree of neuronal damage in the cervical spinal cord in MS. Spectra were acquired from spinal cord and brain in 11 patients with MS (expanded disability status score [EDSS], range 2.5-7.0) and 11 controls. Brain lesion volume and spinal cord cross-sectional area were measured. Concentration of the neuronal metabolite N-acetyl-aspartate ([NAA]) was reduced in the spinal cord in MS patients relative to controls (reduced by 32%, P < 0.05), indicating significant neuronal damage. Additionally, the spinal cord was significantly atrophied in MS patients (15%, P < 0.001). No significant reduction in brain [NAA] was seen in the MS group. There were no correlations between clinical measures and cord atrophy or brain lesion volume on MRI; however, spinal cord [NAA] correlated with the cerebellar subscore of the neurological assessment (P < 0.005), while brain [NAA] correlated with disease duration (P < 0.05). MRS demonstrated cellular damage within the cord over and above the tissue atrophy seen by MRI. Combining MRI and MRS may therefore give a more complete picture of neurodegeneration in the spinal cord.