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目的 探讨磁共振灌注成像评价急性期单侧幕上大脑中动脉区脑梗死后对侧小脑半球灌注量改变的诊断价值.资料与方法 搜集 38 例幕上急性期脑梗死患者进行双侧小脑半球磁共振灌注成像(perfusion-weightedimaging,PWI),通过测量双侧小脑半球相对脑血容量(relalive cerebral blood volume,rCBV)、相对脑血流量(relalivecerebral blood flow,rCBF)和平均通过时间(relalive mean transit time,rMTT)及达峰时间(relalive time to peak,rTTP),判断幕上梗死病灶对侧小脑半球的灌注情况.结果 38 例中,16 例患者对侧小脑半球的 rTTP 延长,较健侧延长约(133.28±70.25)%;rMTT 值较健侧延长约(82.78±91.22)%,但无统计学意义(P=0.112,P>0.05);rCBF 较健侧降低约(53.74±41.56)%;rCBV 较健侧降低约(100.58±91.72)%.结论 部分幕上脑梗死患者可造成病变对侧小脑半球低灌注,并与梗死原发灶的体积相关,提示这些患者可能存在交叉性小脑机能联系不能(crossedcerebellar diaschisis,CCD). 相似文献
143.
CT平扫对椎基底动脉扩张延长症的诊断价值 总被引:1,自引:1,他引:0
目的 探讨CT平扫在椎基底动脉扩张延长症(VBD)诊断中的应用价值.方法 分析27例VBD患者的头部CT平扫表现,并与同期多层螺旋CT血管成像(MSCTA)检查对照.结果 4例(14.8%)基底动脉显示不清,19例(70.4%)显示基底动脉增粗、迂曲,4例(14.8%)表现为桥小脑角区或桥前池肿块,11例(47.8%)基底动脉壁可见钙化.以MSCTA为标准,CT平扫对VBD的敏感度为85.2%.27例中,发现后循环供血区腔隙性脑梗死10例(37.0%),大面积脑梗死2例(7.4%),左侧丘脑出血1例(3.7%),蛛网膜下腔出血1例(3.7%),脑积水4例(14.8%).结论 CT平扫对VBD诊断具有较高的敏感性,可作为VBD的影像学筛查方法 之一. 相似文献
144.
目的 探讨多层螺旋CT血管成像(MSCTA)在椎基底动脉扩张延长症(VBD)中的应用价值及临床意义.方法 对33例VBD患者的影像资料进行回顾性分析,并与对照组(40例)比较后循环血管狭窄性病变和脑梗死的发生率.结果 33例扩张的椎基底动脉直径4.8~14.3 mm,迂曲的基底动脉和椎动脉颅内段长度分别为30.3~41.7 mm 和23.9~42.2 mm,33例中发现大脑后动脉及椎动脉狭窄或闭塞11例,后循环供血区腔隙性脑梗死15例,大面积脑梗死3例;对照组40例中,椎动脉及大脑后动脉闭塞各1例,椎基底动脉和(或)大脑后动脉狭窄22例,后循环供血区腔隙性脑梗死7例,大面积脑梗死3例,2组间后循环供血区腔隙性脑梗死发生率差异有统计学意义(P<0.05).结论 VBD可能是后循环供血区腔隙性脑梗死的重要危险因素;MSCTA结合原始图像可以清晰显示VBD及其颅内伴随病变. 相似文献
145.
神经机能联系不能是指脑内某一局灶损伤区域的兴奋性传出冲动丧失,致神经系统其他特异性区域对刺激的反应性减弱,并且这种功能障碍的发生是突然的,在损伤灶与受累的远隔区域间有神经解剖的联系[1].目前多认为交叉性小脑机能联系不能(crossed cerebellar diaschisis,CCD)的出现与皮质-桥脑-小脑通路(conical-pons-cerebellar pathway,CPC)损伤有关,此外,尚有学者<'[2-3]>认为CCD的发生与患者小脑血流动力学改变和(或)小脑迟发性神经元死亡等有关.作者对急性期单侧幕上大脑中动脉供血区脑梗死病例进行脑磁共振灌注成像(perfusion weighted imaging,PWI),旨在探讨所测得的对侧小脑半球血流动力学改变在CCD发生中的作用及意义. 相似文献
146.
脑膜型囊虫病的磁共振成像诊断 总被引:2,自引:0,他引:2
目的探讨磁共振成像(MRI)对脑膜型囊虫病的诊断价值。资料与方法回顾性分析经临床证实的21例脑膜型囊虫病的MRI表现特点。2l例均行MR平扫,7例同时行MR增强扫描。结果21例脑膜型囊虫病中,单纯性脑膜型囊虫8例(38.1%),混合型13例(61.9%)。其中19例脑膜型囊虫多发,呈葡萄串状生长,2例单发,呈分叶状。囊虫发生于外侧裂9例,鞍上池6例,小脑桥脑角池4例,前纵裂池1例,同时发生于鞍上池与小脑桥脑角池1例。囊虫囊泡在T1WI上等于或稍高于脑脊液(CSF)信号,T2WI上等于CSF信号。囊泡壁在轴面T1WI上显示较为清楚,一般呈边缘光滑的细线样稍高信号影,增强后轻度强化;所有脑膜型囊虫内均未见头节显示。结论MRI是诊断脑膜型囊虫病的首选影像学检查方法。 相似文献
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149.
Objective: To evaluate the application value of multislice computed tomographic perfusion imaging (MSCTPI) and multislice computed tomographic angiography (MSCTA) on traumatic cerebral infarction.
Methods: MSCTA was performed on 10 patients who were initiailly diagnosed as traumatic cerebral infarction by normal conventional computed tomography (NCCT), among whom, 3 patients were examined by MSCTPI simultaneously. Reconstructed images of the intracranial artery were made with techniques of maximum intensity projection (MIP) and volume rendering (VR) from MSCTA scanning data. Then the graph of function of four parameters, regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), mean transit time (MTT), and time to peak (TTP), acquired by the perfusing analysis software was obtained.
Results: Among the 10 patients with traumatic cerebral infarction, 6 showed complex type on NCCT, which depicted abnormality on MSCTA, and 4 showed simple type on NCCT, which had negative results on MSCTA. Among the 4 patients with abnormal great vessels, 2 suffered from stenosis or occlusion of the middle cerebral artery, 1 from spasm of the anterior cerebral artery, and 1 from spasm of the vertebral-basal artery. The image of MSCTPI of 1 patient with massive cerebral infarction on the right cerebral hemisphere confirmed by CT was smaller than those of the other patients, which showed occlusion of the ipsilateral middle cerebral artery on MSCTA, Among the 6 patients whose MSCTA showed no abnormality, 4 showed simple infarction and 2 showed complex infarction. The infarction focus of 5 patients occurred in the basal ganglia and 1 in the splenium of corpus callosum. Among the 2 cases of small cerebral infarction volume on NCCT, one was normal, the other showed hypoperfusion on MSCTPI and was normal on MSCTA.
Conclusion: The combination of MSCTPI and MSCTA is very useful for evaluating the change of intracranial artery in ischemic regions and assessing the cerebral h 相似文献
Methods: MSCTA was performed on 10 patients who were initiailly diagnosed as traumatic cerebral infarction by normal conventional computed tomography (NCCT), among whom, 3 patients were examined by MSCTPI simultaneously. Reconstructed images of the intracranial artery were made with techniques of maximum intensity projection (MIP) and volume rendering (VR) from MSCTA scanning data. Then the graph of function of four parameters, regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), mean transit time (MTT), and time to peak (TTP), acquired by the perfusing analysis software was obtained.
Results: Among the 10 patients with traumatic cerebral infarction, 6 showed complex type on NCCT, which depicted abnormality on MSCTA, and 4 showed simple type on NCCT, which had negative results on MSCTA. Among the 4 patients with abnormal great vessels, 2 suffered from stenosis or occlusion of the middle cerebral artery, 1 from spasm of the anterior cerebral artery, and 1 from spasm of the vertebral-basal artery. The image of MSCTPI of 1 patient with massive cerebral infarction on the right cerebral hemisphere confirmed by CT was smaller than those of the other patients, which showed occlusion of the ipsilateral middle cerebral artery on MSCTA, Among the 6 patients whose MSCTA showed no abnormality, 4 showed simple infarction and 2 showed complex infarction. The infarction focus of 5 patients occurred in the basal ganglia and 1 in the splenium of corpus callosum. Among the 2 cases of small cerebral infarction volume on NCCT, one was normal, the other showed hypoperfusion on MSCTPI and was normal on MSCTA.
Conclusion: The combination of MSCTPI and MSCTA is very useful for evaluating the change of intracranial artery in ischemic regions and assessing the cerebral h 相似文献
150.