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151.
A case of infantile Krabbe's disease was first recognised as areas of relatively increased density on CT in the thalamus lateral geniculate body and dentate nucleus. These sites were subsequently shown on MRI to have a paramagnetic effect, being characterised by short T2 and T1. Subsequent examinations showed development of atrophy and high signal in white matter.  相似文献   
152.
Introduction and background A 3-year-old Bosnian girl with a large symptomatic brainstem and multiple supratentorial cavernous angiomas, who underwent neurosurgical treatment, is presented. As multiple cavernomas are more common in familial cases, genetic analyses and neuroradiological imaging were performed in the patient and her parents to see whether there was any evidence for inheritance. This information is important for genetic counseling and provision of medical care for at-risk relatives. Currently, no recommendation is available on how to manage these cases.Results Genetic analyses demonstrated a novel CCM1 frameshift mutation (c.1683_1684insA; p.V562SfsX6) in the child and the asymptomatic 27-year-old mother. Sensitive gradient-echo magnetic resonance imaging of the mother revealed multiple supratentorial lesions, whereas analogous imaging of the father showed no pathological findings.Conclusion This case exemplifies that seemingly sporadic cases with multiple lesions might well be hereditary and that presymptomatic genetic testing of family members may identify relatives for whom clinical and neuroradiological monitoring is indicated.  相似文献   
153.
脑囊虫病人血清、脑脊液中抗体在MRI各期的变化   总被引:1,自引:0,他引:1  
目的 检测脑囊虫病人血清和脑脊液中抗体在MRI各期的变化。方法 用抑制性ELISA法检测血清及脑脊液中的抗体。同时根据MRI表现将病例分为活动期、退变期、非活动期。结果 在69个病例中,脑脊液中抗体阳性率分别是:活动期75.00%,退变期62.50%,非活动期17.24%;血清中是81.25%、16.67%、22.22%。在相应各期中,脑脊液和血清抗体阳性率无显著性差别。结论 在影像学的不同时期抗体阳性率存在明显的变化。  相似文献   
154.
目的探讨急性桥脑旁正中动脉入口部梗死(branch atheromatous disease,BAD)的临床特点。方法回顾性分析1997~2003年本院神经内科收治的82例桥脑BAD的临床表现、MRI影像特点、脑干听觉诱发电位(BAEP)表现、危险因素。结果本组病例的临床特点是:平均发病年龄69.2岁,男性/女性=46/36,56/82病情呈进行性发展,75/82有构音障碍,72/82有肢体偏瘫,29/82为高度肢体瘫痪,27/82有轻度意识障碍,6/82伴有不全Homer征,49/82出现面部或(和)偏侧肢体感觉减退,25/82出现周围性面瘫,42/82有非旋转性头晕;13/82有眼球运动障碍。MRI表现有:梗死灶位于桥脑中上部、达桥脑表面,楔形,内侧位于桥脑旁正中、呈类似直线,可显示出基底动脉壁不整;危险因素方面除高血压外还与糖尿病、脂质代谢异常有关。结论根据临床特点及MRI表现正确诊断出桥脑BAD,以指导进一步的病因治疗及预防。  相似文献   
155.
单次激发半傅立叶FSE序列MRCP的应用   总被引:1,自引:0,他引:1  
目的评价单次激发半傅立叶FSE序列MRCP图像质量及诊断价值,分析胆道梗阻性疾病的MRCP影像学表现。方法218例病人行单次激发半傅立叶FSE序列MRCP扫描,然后对图像进行质量评价,根据ERCP及手术结果对照分析胆道梗阻性疾病的MRCP的影像学征象和特点,讨论单次激发半傅立叶FSE序列MRCP在胆道梗阻性疾病中的诊断价值。结果单次激发半傅立叶FSE序列MRCP扫描时间为5~7S,优良图像为82.5%,合格图像为10,6%,差为6.9%。单次激发半傅立叶FSE序列MRCP在胆道梗阻性疾病中,对各类梗阻疾病的定位诊断率为100%,梗阻端形态,胆胰管之间的关系均可显示。病因定性诊断率为95.5%。结论单次激发半傅立叶FSE序列MRCP不受呼吸运动影响,图像优质率高,扫描速度快,可显示各种疾病的胆胰管梗阻改变,对诊断较小的结石及泥沙样结石有较大的价值,诊断较早期胆管癌准确率高,可满足临床诊断的要求。  相似文献   
156.
中央沟上段及其邻近沟回的体表定位及其临床意义   总被引:2,自引:0,他引:2  
目的:探讨在MRI和CT图像上观测中央沟上段及其邻近沟回的特征,进行精确体表定位。方法:30例成人头颅和扫描无颅恼器质性病变10份CT,100份MRI片,在头颅正中欠状面上观测头颅外形和平行于耳眦线平而以上100mm内的前后正巾线的中点及中垂线。在横位图像上观测中央沟上段及其邻近沟回的特征和二维坐标参数。结果:成人头颅近似标准球形。住82%头颅卜平行耳眦线平面的正中点的的投影在垂直耳眦线过外耳道的直线卜,另外18%偏离基线面中垂线小于7mm。上段中央沟在耳眦线平面上70~95mm。84%额上沟与中央前沟相交呈倒T字征,交点住前后中线旁24~27mm,耳眦线平面的中垂线前2~6mm。中央沟上段起点前后中线旁1~15mm,耳眦线平而的中垂线后12~28mm,手结征98%。中央后沟在中央沟之后8~13mm与其平行。结论:每人上段中央沟及其邻近沟回的特征能被MRI精确体表定位。  相似文献   
157.
A variety of continuous and pulsed arterial spin labeling (ASL) perfusion MRI techniques have been demonstrated in recent years. One of the reasons these methods are still not routinely used is the limited extent of the imaging region. Of the ASL methods proposed to date, continuous ASL (CASL) with a separate labeling coil is particularly attractive for whole-brain studies at high fields. This approach can provide an increased signal-to-noise ratio (SNR) in perfusion images because there are no magnetization transfer (MT) effects, and lessen concerns regarding RF power deposition at high field because it uses a local labeling coil. In this work, we demonstrate CASL whole-brain quantitative perfusion imaging at 3.0 T using a combination of strategies: 3D volume acquisition, background tissue signal suppression, and a separate labeling coil. The results show that this approach can be used to acquire perfusion images in all brain regions with good sensitivity. Further, it is shown that the method can be performed safely on humans without exceeding the current RF power deposition limits. The current method can be extended to higher fields, and further improved by the use of multiple receiver coils and parallel imaging techniques to reduce scan time or provide increased resolution.  相似文献   
158.
A previously developed eigenvector formalism is adapted to off-resonance in the transient response of quasiperiodic steady-state free precession (SSFP) sequences, including TrueFISP as a special case. The effective relaxation rates for essentially parallel and perpendicular deviations from the steady state are determined analytically in leading order perturbation theory. The latter are a known cause of oscillatory artifacts and therefore constitute the main target of a variety of preparation techniques. In addition, the former also play a dominating role in applications such as inversion recovery (IR) TrueFISP, which intentionally measure far away from the equilibrium. For both components, the approach toward equilibrium turns out to depend sensitively on field inhomogeneities, especially for smaller ratios of T2/T1. For the perpendicular deviations, the calculations show that--except very close to banding artifacts, where the steady-state signal is almost zero--field inhomogeneities additionally increase their effective relaxation rate almost as much as in the free induction decay (FID). The analytical results are tested against numerical simulation and MR measurements.  相似文献   
159.
肾上腺脑白质营养不良MRI表现(附3例报告及文献复习)   总被引:1,自引:0,他引:1  
目的 探讨肾上腺脑白质营养不良的MRI特征,提高对本病的认识。方法 回顾性分析3例经临床和生化证实的。肾上腺脑白质营养不良患者的MRI表现。结果 3例患者均表现为双侧对称性侧脑室三角区白质病变,T1WI呈低信号,T2WI呈高信号,经胼胝体压部相连,呈蝶翼状分布。结论肾上腺脑白质营养不良的MRI表现具有典型特征,MR检查能准确反映病变的病理变化、范围及进展情况。MRI作为一种无创性并且敏感的检查方法,在对肾上腺脑白质营养不良的诊断和治疗方面具有重要的指导意义。  相似文献   
160.
Objectives:  The aims of this paper are to provide an overview of neuroimaging findings specific to bipolar disorder and suicide, and to consider rational approaches to the design of future in vivo studies in youth at risk.
Methods:  Neuroimaging and related neurobiological literature pertaining to bipolar disorder and suicide in adult and pediatric samples was reviewed in a non-quantitative manner.
Results:  Specific structural and functional brain findings in bipolar disorder are described, where possible in the context of relevant current neurobiological theories of etiology. Diagnostic and prognostic implications are discussed.
Conclusions:  The simultaneous use of complementary neurobiological approaches may be a powerful way of identifying and validating factors reliably associated with bipolar disorder and suicide. A profile of neurobiological markers with which to screen for bipolar disorder and suicide risk may provide for earlier and more accurate diagnosis, perhaps even in the pre- or subsyndromal stages in high-risk youth.  相似文献   
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