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1.
大脑灰质异位症临床表现及影像学特征   总被引:6,自引:0,他引:6  
目的探讨大脑灰质异位症临床表现及其影像学特征。方法回顾性分析3例经CT及MRI检查证实为大脑灰质异位症患的临床表现及影像学特征?结果3例大脑灰质异位症患合并其他脑部发育畸形,如脑裂、透明隔缺如,其临床表现为反复频繁的癫痫发作且呈迟发性难治性癫痫、智力低下及运动系统受损,CT及MRI特征性表现为左额、颞、顶灰质团块突人大晒半卵圆区及侧脑室旁的白质内,并见脑裂畸形;右侧大脑半球中央沟明显加深,其周围灰质伸入白质区域,并部分突向右侧侧脑室体部,透明隔部分缺如=抗癫痫药物可作为对症治疗,γ-刀可在一定程度上控制癫痫发作。结论必须提高对大脑灰质异位症的认识,熟悉其CT及MRI表现及其与难治性癫痫的关系,以便及时诊断和治疗:  相似文献   

2.
Prospective clinical and magnetic resonance imaging (MRI) studies were performed over a period of 2-3 years on 51 MS patients. Comparing cerebral MRI and neurological evaluation for sensitivity in detecting disease activity, follow-up MRI turned out to be superior to standardized clinical assessment. In particular, an interval during which the clinical findings remain stable may not necessarily indicate that there is no florid inflammatory activity during this time. The morphological progression demonstrated a preference towards periventricular localization around the posterior horns of the lateral ventricles, and non-periventricularly in the frontal white matter. Longitudinal MRI studies of the disease activity can be an aid in obtaining a more definite diagnosis. Patients having had the disease for a longer period showed a more rapid clinical and morphological progression. Clinical progression and an increase in periventricular involvement were observed more often in the primary unremitting-progressive form of MS than in the relapsing-remitting form.  相似文献   

3.
Periventricular Nodular Heterotopia: Epileptogenic Findings   总被引:6,自引:3,他引:3  
Summary: Purpose : We studied 17 patients with periventricular nodular heterotopia (PNH) to further investigate the electroclinical pictures and semiology of the associated seizures.
Methods : PNH was diagnosed by means of magnetic resonance imaging (MRI). The patients' clinical and familial histories were carefully analyzed, and their electroclinical features and course of epilepsy followed for periods ranging from 10 months to 22 years. The electroclinical data were compared with those of previously reported PNH cases.
Results : The patients were subdivided into those with bilateral (7) and unilateral (10) PNH. The former were mainly characterized by structural abnormalities in the posterior cerebral fossa and multiple seizure types; the latter were characterized by the paratrigonal location of the malformation and, frequently, by elementary seizures with a visual or auditory onset. Focal seizures were drug resistant in most cases. The interictal EEG abnormalities were always focal and consistent with the location of the PNH. A previously unreported photic driving of posterior background activity was observed in all patients and was always consistent with the PNH location.
Conclusions : Conclusions: Our present findings and previously reported data show that bilateral and unilateral PNH cases are different in their morphological and electroclinical features and may be determined by different etiologies. The female predominance, frequent familial occurrence, and positive family history for epilepsy suggest that genetic factors may be involved in the genesis of bilateral and symmetrical PNH, whereas the presence of prenatal risk factors and its location in the watershed paratrigonal area suggest that vascular mechanisms may determine unilateral PNH.  相似文献   

4.
阿尔茨海默病脑磁共振研究   总被引:1,自引:0,他引:1  
目的 了解Alzheimer病(AD)脑结构性变化的特点及与健康老人增龄性改变的差异。方法 对22例AD和29例健康老人分别按年龄为60~65岁、66~70岁和70岁以上三组,AD为ad1、ad2和ad3组,健康老人为nor1、nor2和nor3组。全部对象作MRI检查。结果 nor3的灰质体积、总脑脊液体积及右侧海马体积与nor1和nor2相比有显著差异;与健康老人相比,AD的灰质体积,双侧海马体积显著降低,而总脑脊液、脑室外脑脊液、侧脑室、三脑室和四脑室体积显著升高。结论 与健康老人增龄性变化相比,AD脑结构性改变的涉及范围广,变化幅度大。  相似文献   

5.
双侧脑室旁结节状灰质异位症患者11例影像与临床研究   总被引:1,自引:0,他引:1  
目的分析双侧脑室旁结节状灰质异位症(BPNH)的影像特征与所致癫癎的临床特点和疗效。方法MRI确诊的BPNH患者11例,根据是否合并其他神经系统解剖异常分为单纯BPNH组和叠加BPNH组,随访1~10年。对照分析2组患者的临床特点和药物治疗长期预后的差异。结果单纯BPNH组患者7例,发病年龄8~32岁,7例患者精神行为智力发育正常,癫癎发作均为部分性发作,4例有异位灰质结节部位的癎样放电,5例有发作间期的颞叶癎样放电,7例患者经卡马西平治疗均有效;叠加BPNH组患者4例,发病年龄3~8个月,均有早期的精神运动发育迟缓,癫癎发作频繁,存在抗癫癎药物抵抗。4例BPNH患者合并有心血管系统畸形。结论单纯BPNH组出现癫癎发作的年龄较叠加BPNH组晚,患者精神行为智力发育正常,发作形式均为部分性发作,对卡马西平治疗敏感,预后好。异位灰质结节部位和颞叶的癎样放电是单纯BPNH组患者的脑电图特征。应注意BPNH患者其他系统疾病的诊断,早期进行治疗。  相似文献   

6.
Objectives: Functional and postmortem studies suggest that the orbitofrontal cortex (OFC) is involved in the pathophysiology of bipolar disorder (BD). This anatomical magnetic resonance imaging (MRI) study examined whether BD patients have smaller OFC gray matter volumes compared to healthy comparison subjects (HC). Methods: Twenty‐eight BD patients were compared to 28 age‐ and gender‐matched HC. Subjects underwent a 1.5T MRI with 3D spoiled gradient recalled acquisition. Total OFC and medial and lateral subdivisions were manually traced by a blinded examiner. Images were segmented and gray matter volumes were calculated using an automated method. Results: Analysis of covariance, with intracranial volume as covariate, showed that BD patients and HC did not differ in gray matter volumes of total OFC or its subdivisions. However, total OFC gray matter volume was significantly smaller in depressed patients (n = 10) compared to euthymic patients (n = 18). Moreover, total OFC gray matter volumes were inversely correlated with depressive symptom intensity, as assessed by the Hamilton Depression Rating Scale. OFC gray matter volumes were not related to lithium treatment, age at disease onset, number of episodes, or family history of mood disorders. Conclusions: Our results suggest that abnormal OFC gray matter volumes are not a pervasive characteristic of BD, but may be associated with specific clinical features of the disorder.  相似文献   

7.
Aims: Previous morphometric studies using magnetic resonance imaging (MRI) have revealed structural brain abnormalities in obsessive–compulsive disorder (OCD). The aim of the present study was to investigate the alterations in brain structure of patients with OCD using a voxel‐based morphometry (VBM) method. Methods: Sixteen patients with OCD free of comorbid major depression, and 32 sex‐ and age‐matched healthy subjects underwent MRI using a 1.5‐T MR scanner. OCD severity was assessed with the Yale–Brown Obsessive–Compulsive Scale (mean ± SD: 22 ± 7.6; range: 7–32). MR images were spatially normalized and segmented using the VBM5 package ( http://dbm.neuro.uni‐jena.de/vbm/ ). Statistical analysis was performed using statistical parametric mapping software. Results: Significant reductions in regional gray matter volume were detected in the left caudal anterior cingulate cortex and right dorsal posterior cingulate cortex in the patients with OCD as compared to healthy controls (uncorrected, P < 0.001). No significant differences in white matter volumes were observed in any brain regions of the patients. No significant correlation between Yale–Brown Obsessive–Compulsive Scale score and regional gray matter or white matter volume was observed. Conclusions: Regional gray matter alteration in the dorsal cingulate cortex, which is suggested to play a role in non‐emotional cognitive processes, may be related to the pathophysiology in OCD.  相似文献   

8.
Periventricular nodular heterotopia (PNH) is a brain malformation clinically characterized by the triad of epilepsy, normal intelligence, and dyslexia. We investigated the structure–function relationship between cerebral volumes and cognitive ability in this disorder by studying 12 subjects with PNH and 6 controls using volumetric analysis of high-resolution anatomical MRI and neuropsychological testing. Total cerebral volumes and specific brain compartment volumes (gray matter, white matter, and cerebrospinal fluid) in subjects with PNH were comparable to those in controls. There was a negative correlation between heterotopic gray matter volume and cortical gray matter volume. Cerebral and cortical volumes in PNH did not correlate with Full Scale IQ, unlike in normal individuals. Our findings support the idea that heterotopic nodules contain misplaced neurons that would normally have migrated to the cortex, and suggest that structural correlates of normal cognitive ability may be different in the setting of neuronal migration failure.  相似文献   

9.
Evidence so far indicates that the consistent association between insular cortex abnormalities and schizophrenia is already present at early phases of the illness. In the present investigation we aimed to study the specificity of insular structural abnormalities in schizophrenia by using region-of-interest morphometry to assess insular cortex morphological characteristics in the same heterogeneous sample of schizophrenia-spectrum patients. The 225 subjects, comprising 82 schizophrenia patients, 36 schizophreniform disorder patients and 24 patients with nonschizophrenic non-affective psychoses, and 83 healthy individuals were investigated. Magnetic resonance imaging brain scans (1.5 T) were obtained and images analysed to evaluate insular cortex morphometric variables. The main resulting measurements were for insular gray matter volume and cortical surface area. The contribution of sociodemographic and clinical characteristics was controlled. Patients with schizophrenia-spectrum disorders did not significantly differ from controls in the insular cortex morphometric variables evaluated (all P’s > 0.11). Clinical variables were not significantly related with insular morphological changes. Noteworthy is the fact that none of the group morphological measurements varied significantly by gender or hemisphere. Neither did we find significant differences when patients with schizophrenia and with other non-affective psychoses were compared. Contrary to our initial hypotheses, we were unable to demonstrate significant morphometric anomalies in a large and heterogeneous sample of patients with a first-episode of schizophrenia-spectrum disorders.  相似文献   

10.
Subcortical and periventricular white matter hyperintensities (WMHs) may have different associations with cognition and pathophysiology. The aim of the present study is to develop an automated method for construction of periventricular WMH maps that enables the analysis of between-group differences in WMH location and characteristics in the periventricular region without the requirement of prior boundary definition. To avoid influence of WMHs on spatial normalization, a reference image of the lateral ventricles was constructed based on images of 24 subjects. Construction was not biased to a single subject. WMHs were segmented by k-nearest neighbor-based classification of magnetic resonance inversion recovery and fluid attenuated inversion recovery images. Cerebrospinal fluid segmentations of individual subjects were nonrigidly mapped to the reference image of the lateral ventricles. The subject's WMHs were transformed to the reference space accordingly. Spatial normalization accuracy was validated using measures of overlap and of displacement relative to the boundary of the lateral ventricles. After spatial normalization, the boundaries of the lateral ventricles closely matched the reference image and in an area of approximately 1 cm around the lateral ventricles the relative displacement was less than 1 mm. To illustrate the method, it was applied to 61 patients with Type 2 diabetes and 26 control subjects, whereupon periventricular WMH maps were constructed and compared. The proposed method is particularly suited to analyze WMH distribution differences at the level of the lateral ventricles between large groups of patients.  相似文献   

11.
White matter lesions (WML) on magnetic resonance imaging (MRI) brain scans are associated with ageing. They are unrelated to specific disorders, and their impact on cognitive and other brain functions is poorly characterized. Pathological studies often omit systematic survey of WML because of the need to study multiple full coronal tissue blocks, and uncertainty over the significance of lesions identified in periventricular and deep subcortical regions. Post-mortem MRI provides a means of mapping WML but the sensitivity and specificity of the method are unresolved. In this study post-mortem MRI of WML in fixed brain slices was compared with pathology in 33 brains donated to the Medical Research Council Cognitive Function and Ageing Study (MRC CFAS). This study shows that MRI detection of WML was less sensitive than pathology: periventricaular lesions (PVL) sensitivity = 95% (87-99%), specificity = 71% (44-90%); deep subcortical lesions (DSCL) sensitivity = 86% (79-93%), specificity = 80% (72-88%). False negative MRI was associated with milder pathology, but lesions detected by myelin attenuation alone showed both microglial and endothelial activation. Therefore post-mortem MRI of formalin-fixed brain slices is a reliable method to obtain systematic data on the severity and distribution of cerebral white matter disease, and appears to detect those WML most likely to have clinical impact.  相似文献   

12.
BACKGROUND/PURPOSE: Gray matter involvement in multiple sclerosis (MS) is of growing interest with respect to disease pathogenesis. Magnetization transfer imaging (MTI), an advanced MRI technique, is sensitive to disease in normal appearing white matter (NAWM) in patients with MS. DESIGN/METHODS: We tested if MTI detected subcortical (deep) gray matter abnormalities in patients with MS (n= 60) vs. age-matched normal controls (NL, n= 20). Magnetization transfer ratio (MTR) maps were produced from axial proton density, conventional spin-echo, 5 mm gapless slices covering the whole brain. Region-of-interest-derived MTR histograms for the caudate, putamen, globus pallidus, thalamus, and NAWM were obtained. Whole brain MTR was also measured. RESULTS: Mean whole brain MTR and the peak position of the NAWM MTR histogram were lower in patients with MS than NL (P < .001) and mean whole brain MTR was lower in secondary progressive (SP, n= 10) than relapsing-remitting (RR, n= 50, P < .001) patients. However, none of the subcortical gray matter nuclei showed MTR differences in MS vs. NL, RR vs. SP, or SP vs. NL. CONCLUSIONS: The MTI technique used in this cohort was relatively insensitive to disease in the deep gray matter nuclei despite showing sensitivity for whole brain disease in MS. It remains to be determined if other MRI techniques are more sensitive than MTI for detecting pathology in these areas.  相似文献   

13.

BACKGROUND AND PURPOSE

A pipeline for fully automated segmentation of 3T brain MRI scans in multiple sclerosis (MS) is presented. This 3T morphometry (3TM) pipeline provides indicators of MS disease progression from multichannel datasets with high‐resolution 3‐dimensional T1‐weighted, T2‐weighted, and fluid‐attenuated inversion‐recovery (FLAIR) contrast. 3TM segments white (WM) and gray matter (GM) and cerebrospinal fluid (CSF) to assess atrophy and provides WM lesion (WML) volume.

METHODS

To address nonuniform distribution of noise/contrast (eg, posterior fossa in 3D‐FLAIR) of 3T magnetic resonance imaging, the method employs dual sensitivity (different sensitivities for lesion detection in predefined regions). We tested this approach by assigning different sensitivities to supratentorial and infratentorial regions, and validated the segmentation for accuracy against manual delineation, and for precision in scan‐rescans.

RESULTS

Intraclass correlation coefficients of .95, .91, and .86 were observed for WML and CSF segmentation accuracy and brain parenchymal fraction (BPF). Dual sensitivity significantly reduced infratentorial false‐positive WMLs, affording increases in global sensitivity without decreasing specificity. Scan‐rescan yielded coefficients of variation (COVs) of 8% and .4% for WMLs and BPF and COVs of .8%, 1%, and 2% for GM, WM, and CSF volumes. WML volume difference/precision was .49 ± .72 mL over a range of 0–24 mL. Correlation between BPF and age was r = .62 (P = .0004), and effect size for detecting brain atrophy was Cohen's d = 1.26 (standardized mean difference vs. healthy controls).

CONCLUSIONS

This pipeline produces probability maps for brain lesions and tissue classes, facilitating expert review/correction and may provide high throughput, efficient characterization of MS in large datasets.  相似文献   

14.
BACKGROUND AND PURPOSE: Elevation in pulsatility indices (PIs) as measured by transcranial Doppler (TCD) have been postulated to reflect downstream increased vascular resistance caused by small-vessel ischemic disease. METHODS: The authors retrospectively compared TCD PIs and magnetic resonance imaging (MRI) manifestations of small-vessel disease in 55 consecutive patients who underwent TCD studies and brain MRI within 6 months of each other during a 2-year period. RESULTS: Correlations between TCD middle cerebral artery PIs and MRI measures were as follows: periventricular hyperintensity (PVH) = 0.52 (P < .0001), deep white matter hyperintensity (DWMH) = 0.54 (P < .0001), lacunar disease = 0.31 (P = .02), and combined PVH/DWMH/lacunes = 0.54 (P < .0001). Correlation between pontine ischemia and vertebrobasilar PIs was 0.46 (P = .0004). Univariate analysis showed that age, elevated PI, and hypertension strongly correlated with white matter disease measures. After adjusting for these factors in a multivariate Poisson regression analysis, PI remained an independent predictor of white matter disease. Receiver operator curve analyses identified PI cut points that allowed discrimination of PVH with 89% sensitivity and 86% specificity and discrimination of DWMH with 70% sensitivity and 73% specificity. CONCLUSIONS: Elevation in PIs as measured by TCD shows strong correlation with MRI evidence of small-vessel disease. TCD may be a useful physiologic index of the presence and severity of diffuse small-vessel disease.  相似文献   

15.
目的探讨脑灰质异位症影像学特征及与临床症状的关系。方法分析了36例经三名以上神经影像学医师诊断为脑灰质异位症病例。其中男性16例,女性20例,年龄在8个月~43岁,平均年龄中位值14.2±0.5岁。主要临床症状表现为癫疒间、智力低下、运动障碍。结果我们把灰质异位症分为5型:①室管膜下型(15例);②局灶性皮层下型(10例);③弥漫型(4例);④脑裂畸形型5例;⑤混合型(2例)。灰质异位症还常可并发其它的一些颅脑畸形。结论灰质异位症的诊断主要依据临床表现和影像学征象。不同类型的灰质异位症具有不同的临床表现。在诊断时应与其它病变进行鉴别。  相似文献   

16.
Magnetic resonance imaging (MRI) was performed on five patients with infantile spasms who were treated with relatively low doses of adrenocorticotrophic hormone (ACTH) to study the extent of brain shrinkage induced by ACTH therapy. MRI prior to ACTH therapy revealed periventricular hyperintensity (PVH) areas and poor myelination in four patients. In one case, MRI performed 2 days after initiation of ACTH therapy also showed PVH and poor myelination. Brain shrinkage was observed 2 weeks after initiation of ACTH therapy. The most impressive follow-up finding upon MRI was the decrease in PVH found in four patients. The differentiation between myelinated white matter and surrounding cortex became poorer in three cases. Cortical atrophy progressed in all patients but ventricular dilation progressed in only one patient. At the end of ACTH therapy, ventricular dilation progressed in all cases. These findings suggest that loss of water not only from periventricular white matter but also from cortex is the main etiological factor of brain shrinkage induced by ACTH.  相似文献   

17.
目的探讨强迫症患者脑灰质和白质结构改变是否在同一样本中反映了相同环路的异常。方法对54例强迫症患者(强迫症组)和54名健康对照(对照组)进行3D结构磁共振成像扫描和弥散张量成像扫描。基于SPM分析软件,采用基于体素的形态学分析方法分析强迫症组全脑灰质体积与对照组的差异;基于FSL软件,采用基于纤维束示踪的空间统计学探讨强迫症组各向异性分数(fractional anisotropy,FA)与对照组的差异。结果与对照组相比,强迫症组左侧额中回、左侧前扣带和旁扣带脑回、左侧中央前回及右侧颞下回灰质体积减小(P<0.05,Alphasim校正),胼胝体体部和胼胝体膝部FA值减小(P<0.05,FWE校正)。结论强迫症患者的灰质体积和白质完整性均存在异常,且异常区域多位于皮质-纹状体-丘脑-皮质环路相关脑区,强迫症的灰、白质结构异常可能同时出现。  相似文献   

18.
目的 研究多发性硬化 (MS)患者认知功能障碍的发生情况及认知改变的病理解剖基础。方法 对 70例MS患者进行韦氏智力量表测查及头颅MRI检查 ,对其中 5 0例患者的头颅MRI成像进行了定量测量 ;7例患者进行了弥散张量成像 (DTI)扫描。结果 智能测试发现MS组全量表智商低于正常 (<90分 )者为 4 0 % (2 8/ 70 ) ,与正常组比较差异有非常显著意义 (P <0 0 1)。智能测试与MRI测量中的两侧尾状核比率相关性最显著 ,其次为胼胝体指数。DTI显示病灶周围看似正常组织、看似正常白质及灰质较对照组相应部位脑组织的表观扩散系数增高 ,各向异性值减低。结论 MS患者中存在认知障碍。病灶的范围及其严重程度 ,包括看似正常白质中的微小病灶的数量和严重程度决定认知障碍的程度。灰质功能障碍也与认知改变有关。  相似文献   

19.
OBJECTIVE: The aim of this study is to assess the significance of an apparent diffusion coefficient (ADC) modality for the diagnosis and follow-up evaluation of ventriculitis. PATIENTS AND METHODS: Twelve patients with ventriculitis were enrolled in this study. Diffusion-weighted (DW) magnetic resonance images (MRI) and ADC maps of the periventricular white matter, intraventricular collections detected in the third or lateral ventricles and normal cerebrospinal fluid (CSF) were obtained. The images and ADC data from each lesion were correlated and then compared amongst the different lesions. CSF studies were performed via external ventricular drain (EVD) catheters or lumbar punctures performed on the same day as ADC mapping. Linear regression was used to analyze relationships among pleocytosis, glucose, chloride, protein content of pus, and ADC counting. RESULTS: A total of 24 ADC values for intraventricular pus and CSF findings were obtained from 12 patients and analyzed. The DW MRI showed marked hyperintensity in purulent lesions, and the corresponding ADC maps revealed prominent hypointensity and decreased ADC values in dependent CSF compared with non-dependent CSF and normal white matter. Dependent CSF is defined as the CSF which is mixed with purulent discharge which is located at the lower portion of the ventricle by gravity. The correlations between ADC counting and pleocytosis, and also protein content were strong: r(2)=-0.84, r(2)=-0.62, respectively (p<0.001). CONCLUSION: A decreased ADC value and increased signal intensity of dependent intraventricular fluid by DW MRI suggests the presence of material with restricted water diffusion in the ventricular space. This is seen in pyogenic ventriculitis when water diffusion is restricted in suppurative fluid. ADC counting is negatively correlated with pleocytosis and the protein content of CSF. Therefore, the ADC value might be a useful non-invasive method for the follow-up evaluation of ventriculitis as well as the diagnosis of it.  相似文献   

20.
Alzheimer's disease (AD) patients exhibit alterations in the functional connectivity between spatially segregated brain regions which may be related to both local gray matter (GM) atrophy as well as a decline in the fiber integrity of the underlying white matter tracts. Machine learning algorithms are able to automatically detect the patterns of the disease in image data, and therefore, constitute a suitable basis for automated image diagnostic systems. The question of which magnetic resonance imaging (MRI) modalities are most useful in a clinical context is as yet unresolved. We examined multimodal MRI data acquired from 28 subjects with clinically probable AD and 25 healthy controls. Specifically, we used fiber tract integrity as measured by diffusion tensor imaging (DTI), GM volume derived from structural MRI, and the graph‐theoretical measures ‘local clustering coefficient’ and ‘shortest path length’ derived from resting‐state functional MRI (rs‐fMRI) to evaluate the utility of the three imaging methods in automated multimodal image diagnostics, to assess their individual performance, and the level of concordance between them. We ran the support vector machine (SVM) algorithm and validated the results using leave‐one‐out cross‐validation. For the single imaging modalities, we obtained an area under the curve (AUC) of 80% for rs‐fMRI, 87% for DTI, and 86% for GM volume. When it came to the multimodal SVM, we obtained an AUC of 82% using all three modalities, and 89% using only DTI measures and GM volume. Combined multimodal imaging data did not significantly improve classification accuracy compared to the best single measures alone. Hum Brain Mapp 36:2118–2131, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

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