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1.
Cerebral micro- and macro-vasculopathy have been described in Fabry disease (FD). Neuronal globotriaosylceramide accumulation in selective cortical and brain stem areas including the hippocampus has been reported by autopsy studies in FD, but clinical surrogates as well as the clinical relevance of these findings have not been investigated so far. We measured the hippocampus volumes in a group of clinically affected patients with FD and correlated the findings with the cognitive performance of the patients. Hippocampal volumes were determined manually on T1-weighted MR-images of 25 FD patients (age 36.5 ± 11.0 years) and 20 age-matched controls. Additionally, individual white matter (WM) and gray matter (GM) volumes were measured using brain segmentation analyses. After controlling for age, white matter lesion (WML) volume, and WM/GM-volumes hippocampal volumes were significantly decreased in FD. These findings were substantially more pronounced in a subgroup of men with FD. WM and WM/GM volumes, and memory function did not significantly differ between patients and controls. In patients with FD hippocampal volumes were neither significantly correlated to WML volume nor to WM or WM/GM volumes. Hippocampus atrophy was not driven by the WML or other brain tissue atrophy and seems to correlate with the neuronal involvement in FD. In this young to middle-aged Fabry cohort the hippocampus degeneration was functionally compensated without memory impairment. Longitudinal studies are needed to determine whether this degenerative component in FD will progress and, in concert with the individual WML-load, predict subsequent cognitive decline.  相似文献   

2.
Although long-term exposure of the brain to increased GH/IGF-1 likely influences cerebral functions, no in vivo studies have been directed towards changes of the brain structure in acromegaly. Here, we used high resolution magnetic resonance images to compare volumes of gray matter (GM), white matter (WM) and cerebrospinal fluid (CSF) of forty-four patients with acromegaly to an age and gender matched, healthy control group (n = 44). In addition, white matter lesions (WMLs) were quantified and graded. Patients exhibited larger GM (+3.7% compared with controls, P = 0.018) and WM volumes (+5.1%, P = 0.035) at the expense of CSF. Differences of WML counts between patients and controls were subtle, however, showing more patients in the 21-40 lesions category (P = 0.044). In conclusion, this MRI study provides first evidence that acromegalic patients exhibit disturbances of the macroscopic brain tissue architecture. Furthermore, acromegalic patients may have an increased risk of neurovascular pathology, likely due to secondary metabolic and vascular comorbidities.  相似文献   

3.
Earlier studies revealed progressive cortical gray matter (GM) loss in childhood-onset schizophrenia (COS) across both lateral and medial surfaces of the developing brain. Here, we use tensor-based morphometry to visualize white matter (WM) growth abnormalities in COS throughout the brain. Using high-dimensional elastic image registration, we compared 3D maps of local WM growth rates in COS patients and healthy children over a 5-year period, based on analyzing longitudinal brain MRIs from 12 COS patients and 12 healthy controls matched for age, gender, and scan interval. COS patients showed up to 2.2% slower growth rates per year than healthy controls in WM (P = 0.02, all P values corrected). The greatest differences were in the right hemisphere (P = 0.006). This asymmetry was attributable to a right slower than left hemisphere growth rate mapped in COS patients (P = 0.037) but not in healthy controls. WM growth rates reached 2.6% per year in healthy controls (P = 0.0002). COS patients showed only a 1.3% per year trend for growth in the left hemisphere (P = 0.066). In COS, WM growth rates were associated with improvement in the Children's Global Assessment Scale (R = 0.64, P = 0.029). Growth rates were reduced throughout the brain in COS, but this process appeared to progress in a front-to-back (frontal-parietal) fashion, and this effect was not attributable to lower IQ. Growth rates were correlated with functional prognosis and were visualized as detailed 3D maps. Finally, these findings also confirm that the progressive GM deficits seen in schizophrenia are not the result of WM overgrowth.  相似文献   

4.
Brain injury is a common complication of sickle cell anaemia (SCA). White matter (WM) and cortical and subcortical grey matter (GM), structures may have reduced volume in patients with SCA. This study focuses on whether silent cerebral infarction (SCI), vasculopathy or anaemia affects WM and regional GM volumes in children living in Africa. Children with SCA (n = 144; aged 5–20 years; 74 male) and sibling controls (n = 53; aged 5–17 years; 29 male) underwent magnetic resonance imaging. Effects of SCI (n = 37), vasculopathy (n = 15), and haemoglobin were assessed. Compared with controls, after adjusting for age, sex and intracranial volume, patients with SCA had smaller volumes for WM and cortical, subcortical and total GM, as well as bilateral cerebellar cortex, globus pallidus, amygdala and right thalamus. Left globus pallidus volume was further reduced in patients with vasculopathy. Putamen and hippocampus volumes were larger in patients with SCA without SCI or vasculopathy than in controls. Significant positive effects of haemoglobin on regional GM volumes were confined to the controls. Patients with SCA generally have reduced GM volumes compared with controls, although some subcortical regions may be spared. SCI and vasculopathy may affect the trajectory of change in subcortical GM and WM volume. Brain volume in non-SCA children may be vulnerable to contemporaneous anaemia.  相似文献   

5.
Selective gray matter damage in neuropsychiatric lupus   总被引:2,自引:0,他引:2  
OBJECTIVE: Damage of brain parenchyma in patients with primary diffuse neuropsychiatric systemic lupus erythematosus (NPSLE) has been indicated by magnetization transfer imaging (MTI). However, the location of MTI abnormalities is unknown. This study was undertaken to assess the distribution of MTI abnormalities over gray matter (GM) and white matter (WM) in SLE patients with a history of NP symptoms without explanatory magnetic resonance imaging (MRI) evidence of focal disease. METHODS: MTI was performed in 24 female SLE patients with a history of diffuse NP symptoms and 24 healthy female controls. Magnetization transfer ratio (MTR) maps were calculated for GM and WM separately, and GM and WM MTR histograms were generated. Univariate and multivariate analyses with age as an additional covariate were performed on the histogram parameters peak location (PL), peak height (PH), and mean MTR. RESULTS: Compared with controls, significantly reduced PH (mean +/- SD 136 +/- 22 arbitrary units versus 151 +/- 13 arbitrary units) and mean MTR (33.3 +/- 1.0 percent units versus 33.6 +/- 0.5 percent units) were found in the GM of NPSLE patients (P = 0.002 and P = 0.033, respectively, in multivariate analyses). No significant differences were observed for WM MTR parameters. CONCLUSION: This is the first study to demonstrate, using MTI, that in SLE patients with a history of NP symptoms and without explanatory focal abnormalities on MRI, the GM is particularly affected. These findings support the hypothesis that neuronal injury may underlie central nervous system manifestations in NPSLE.  相似文献   

6.
Background: Alcohol abuse has detrimental effects on cerebral function, metabolism, and volume. Some of these effects were found to be at least partially reversible with continued abstinence. Furthermore, it has been reported that there are different effects of alcohol on brain volumes for women compared with men, but the results concerning the interaction between alcohol dependence and gender are inconsistent. With this study, we aimed to further investigate this question by examining the global gray matter (GM) and white matter (WM) changes as well as regional and local GM changes detected by voxel‐based morphometry (VBM) in male and female alcoholic patients a few weeks after detoxification and the corresponding changes in a subgroup of these patients 3 months later. Methods: A total of 50 patients, consecutively admitted for alcohol withdrawal treatment, participated in this study and were followed up for at least 3 months into abstinence. High‐resolution structural images were processed with SPM8 using an optimized VBM protocol. Results: Global cerebrospinal fluid (CSF) volume was increased and WM and GM volume decreased equally in male and female patients. A gender by diagnosis interaction was found neither for global nor for regional volumes or VBM data. VBM whole brain analysis yielded a significant GM volume loss in the patient group in the cingulate gyrus and the insula in both hemispheres. Region of interest analysis for the initial and 3 months follow‐up scans yielded significant gains in regional volumes, particularly the cingulate gyrus and the insula in the group of abstinent patients, whereas no volume change at all is found in the patients who had relapsed. Conclusions: Our study confirms widespread cerebral volume loss in recently detoxified alcoholics. The effects of alcohol dependence seem to have equally adverse effects on brain morphometry in males and females.  相似文献   

7.
目的应用扩散张量成像(DTI)技术,探讨皮质下缺血性血管性痴呆(SIVD)患者脑白质变化的特点及不同脑区DTI参数改变与认知的关系。方法对34例SIVD患者(SIVD组)及26例健康老年人(对照组)行DTI扫描,测量双侧前额叶、额叶深部、眶额内侧、下额叶、颞叶、顶叶、枕叶白质及T_2WI高信号区、T_2WI高信号周围正常白质区的分量各向异性(FA)、主各向异性(PA)及表观弥散系数(ADC)值。结果对照组左侧前额叶白质PA值大于右侧,ADC值小于右侧。SIVD组双侧前额叶、双侧额叶深部、下额叶、眶额内侧的FA值及PA值明显下降,平均ADC值升高;双侧顶叶的FA值下降,平均ADC值升高;双侧颞叶、枕叶平均ADC值升高;左侧下额叶、眶额内侧白质的FA与PA值较右侧小;左侧下额叶ADC值较右侧大。病变区及病变周围区的FA和PA值小于正常区,ADC值大于正常区。前额叶FA与简易智能状态检查表评分呈正相关。结论 SIVD患者脑白质FA、PA和ADC改变具有区域选择性,前部及左侧脑区损伤明显,后部及右侧相对保留白质的完整性。DTI是研究SIVD脑白质损伤的一种理想的方法。  相似文献   

8.
The Bcl-2 gene is a major regulator of neural plasticity and cellular resilience. A single-nucleotide polymorphism (SNP) in the Bcl-2 gene, Bcl-2 rs956572, significantly modulates the expression of Bcl-2 protein and cellular vulnerability to apoptosis. This study investigated the association between the Bcl-2 rs956572 SNP and brain structural abnormalities in non-demented elders, and to test the relationship between neuropsychological performance and regional gray matter (GM) volumes. Our sample comprised 97 non-demented elderly men with a mean age of 80.6 ± 5.6 years (range, 65 to 92 years). Cognitive test results, magnetic resonance imaging, and genotyping of Bcl-2 rs956572 were examined for each subject. The differences in regional GM volumes between G homozygotes and A-allele carriers were tested using optimized voxel-based morphometry. Subjects with G homozygotes exhibited significantly worse performance in the language domain of the Cognitive Abilities Screening Instrument (CASI; p = 0.009). They also showed significantly smaller GM volumes in the right middle temporal gyrus (MTG) (BA 21), but larger GM volumes in the left precuneus (BA 31), right lingual gyrus (BA 18), and left superior occipital gyrus (BA 19) relative to A-allele carriers (p < 0.001). A trend toward a positive correlation between right MTG GM volumes and the language domain of CASI was also evident (r = 0.181; p = 0.081). The findings suggest that Bcl-2 rs956572 SNP may modulate cognitive function and regional GM volume in non-demented elderly men, and that this polymorphism may affect language performance through its effect on the right MTG.

Electronic supplementary material

The online version of this article (doi:10.1007/s11357-011-9367-5) contains supplementary material, which is available to authorized users.  相似文献   

9.
BACKGROUND: The main goals are to investigate the effects of chronic active heavy drinking on N-acetylaspartate (NAA) and other metabolites throughout the brain and to determine whether they are affected by family history (FH) of alcoholism and long-term drinking pattern. METHODS: Forty-six chronic heavy drinkers (HD) and 52 light drinkers (LD) were recruited from the community and compared on measures of regional brain structure using magnetic resonance imaging and measures of common brain metabolites in gray matter (GM) and white matter (WM) of the major lobes, subcortical nuclei, brainstem, and cerebellum using short-echo time magnetic resonance spectroscopic imaging. Regional atrophy-corrected levels of NAA, myoinositol (mI), creatine, and choline-containing metabolites were compared as a function of group, FH of alcoholism, and bingeing. RESULTS: Frontal WM NAA was lower in FH-negative HD than FH-positive HD and tended to be lower in women than men. Creatine-containing metabolites in parietal GM were higher in HD than LD. FH-negative compared with FH-positive HD also had more mI in the brainstem and tended to have lower NAA and more mI in frontal GM. Although parietal GM NAA was not significantly lower in HD than LD, it was lower in non-binge drinkers than bingers. Frontal WM NAA was lower in HD than LD, with the difference driven by a small number of women, FH-negative HD, and older age. Lower frontal WM NAA in HD was associated with lower executive and working memory functions and with lower P3b amplitudes at frontal electrodes. CONCLUSIONS: Community-dwelling HD who are not in alcoholism treatment have brain metabolite changes that are associated with lower brain function and are likely of behavioral significance. Age, FH, and binge drinking modulate brain metabolite abnormalities. Metabolite changes in active HD are less pronounced and present with a different spatial and metabolite pattern than reported in abstinent alcoholics.  相似文献   

10.
In this study, volumes of the whole brain, hemispheres, and frontal lobes of young and elderly adults were quantified by an automated method. Effects of age, sex, and side on absolute and relative volumes of the brain structures were evaluated. Compared with the young group, elderly participants showed a 15% volume loss in the whole brain and hemispheres, and a 22% volume loss in the frontal lobes. The relative volume of the left hemisphere in the elderly group decreased more than that of the right hemisphere. Elderly men showed significantly greater left hemisphere and left frontal lobe volume losses than did elderly women, indicating that the larger left hemisphere relative volume reduction is largely contributed to by selective atrophy of the left frontal lobe volume in elderly men. These results may reflect age- and sex-related functional deterioration in the left brain.  相似文献   

11.
To determine whether hypertension, the predominant risk factor for stroke and vascular dementia, is associated with brain atrophy, magnetic resonance imaging (MRI) scans were performed to quantify brain volumes and cerebrospinal fluid spaces. Eighteen otherwise healthy, cognitively normal older hypertensive men (mean +/- SD age, 69 +/- 8 years, duration of hypertension 10-35 years) and 17 age-matched healthy, normotensive male control subjects were studied in a cross-sectional design. Axial proton-density image slices were analyzed using region-of-interest and segmentation analyses. The hypertensive subjects had significantly larger mean volumes of the right and left lateral ventricles (p less than 0.05, both absolute volume and volume normalized to intracranial volume) and a significantly smaller normalized mean left hemisphere brain volume (p less than 0.05) with a trend toward significance for a smaller normalized mean right hemisphere volume (p less than 0.09). Four hypertensive subjects and one healthy control subject were found to have severe periventricular hyperintensities on T2-weighted MRI images. When data for these subjects were removed from the analyses, the normalized lateral ventricle volumes remained significantly larger in the hypertensive group. Lateral ventricle enlargement was not related to age or use of diuretics in the hypertensive group nor to duration of hypertension between 10 and 24 years. Our findings suggest that long-standing hypertension results in structural changes in the brain. Longitudinal studies will determine whether MRI-associated changes are progressive and if such changes identify hypertensive subjects at increased risk for clinically apparent brain dysfunction.  相似文献   

12.
AIMS: The aim of this project was to define normal values of right ventricular (RV) volumes and ejection fraction (EF) in healthy population using 2D echocardiography. METHODS AND RESULTS: The "patient" group comprised 91 healthy volunteers aged 17-62 years. RV volumetry was based on ellipsoidal shell model method. Left ventricular (LV) volumes were assessed by Teichholz formula. All volumes were indexed per m(2) of BSA and the rate distribution of measured and calculated values were evaluated. The normal range of individual parameters was expressed as mean value+/-2 standard deviations (delta). A pair test was used to compare corresponding results of the RV and LV measurements. The regression analysis was used to test the relationship between LV and RV volumes and age. Indexed enddiastolic and endsystolic RV volumes were 79.1+/-29.9ml and 32.6+/-19.7ml, respectively, EF being 50+/-9.7% in men and 58+/-13.6% in women. No correlation with patient's age was observed. CONCLUSION: Enddiastolic and endsystolic volumes of RV were significantly higher than those of LV. EF of RV was lower as compare to LV. Right ventricular EF in men was lower than that in women. There was no correlation between EF and patient's age.  相似文献   

13.
Although modern medical management has lowered overt stroke occurrence in patients with sickle cell disease (SCD), progressive white matter (WM) damage remains common. It is known that cerebral blood flow (CBF) increases to compensate for anemia, but sufficiency of cerebral oxygen delivery, especially in the WM, has not been systematically investigated. Cerebral perfusion was measured by arterial spin labeling in 32 SCD patients (age range: 10-42 years old, 14 males, 7 with HbSC, 25 HbSS) and 25 age and race-matched healthy controls (age range: 15-45 years old, 10 males, 12 with HbAS, 13 HbAA); 8/24 SCD patients were receiving regular blood transfusions and 14/24 non-transfused SCD patients were taking hydroxyurea. Imaging data from control subjects were used to calculate maps for CBF and oxygen delivery in SCD patients and their T-score maps. Whole brain CBF was increased in SCD patients with a mean T-score of 0.5 and correlated with lactate dehydrogenase (r2 = 0.58, P < 0.0001). When corrected for oxygen content and arterial saturation, whole brain and gray matter (GM) oxygen delivery were normal in SCD, but WM oxygen delivery was 35% lower than in controls. Age and hematocrit were the strongest predictors for WM CBF and oxygen delivery in patients with SCD. There was spatial co-localization between regions of low oxygen delivery and WM hyperintensities on T2 FLAIR imaging. To conclude, oxygen delivery is preserved in the GM of SCD patients, but is decreased throughout the WM, particularly in areas prone to WM silent strokes.  相似文献   

14.
Mild cognitive impairment (aMCI) is a clinical condition, with high risk to develop Alzheimer’s disease. Physical exercise may have positive effect on cognition and brain structure in older adults. However, it is still under research whether these influences are true on aMCI subjects with low Ab_42 and high total tau in cerebrospinal fluid (CSF), which is considered a biomarker for AD. Therefore, we aimed to investigate a possible relation between aerobic fitness (AF) and gray matter (GM) volume and AF and white matter (WM) integrity in aMCI with a CSF biomarker. Twenty-two participants with aMCI acquired the images on a 3.0-T MRI. AF was assessed by a graded exercise test on a treadmill. Voxel-based morphometry and tract-based spatial statistic methods were used to analyze the GM volume and WM microstructural integrity, respectively. We correlated AF and GM volume and WM integrity in aMCI (p < 0.05, FWE corrected, cluster with at least five voxels). There was a positive relation between AF and GM volume mostly in frontal superior cortex. In WM integrity, AF was positively correlated with fractional anisotropy and negatively correlated with mean diffusivity and radial diffusivity, all in the same tracts that interconnect frontal, temporal, parietal, and occipital areas (longitudinal fasciculus, fronto-occipital fasciculus, and corpus callosum). These results suggest that aerobic fitness may have a positive influence on protection of brain even in aMCI CSF biomarker, a high-risk population to convert to AD.  相似文献   

15.
BACKGROUND: Short-axis summation (SAS) method applied for right ventricular (RV) volumes and right ventricular ejection fraction (RVEF) measurement with cardiac MRI is time consuming and cumbersome to use. A simplified RVEF measurement is desirable. We compare two such methods, a simplified ellipsoid geometric method (GM) and visual estimate, to the SAS method to determine their accuracy and reproducibility. METHODS: Forty patients undergoing cine cardiac MRI scan were enrolled. The images acquired were analyzed by the SAS method, the GM (area and length measurement from two orthogonal planes) and visual estimate. RVEF was calculated using all three methods and RV volumes using the SAS and GM. Bland-Altman analysis was applied to test the agreement between the various measurements. RESULTS: Mean RVEF was 49 +/- 12% measured by SAS method, 54 +/- 12% by the GM, and 49 +/- 11% by visual estimate. There were similar bias and limits of agreement between the visual estimate and the GM compared to SAS. The interobserver variability showed a bias close to zero with limits of agreement within +/-10% absolute increments of RVEF in 35 of the patients. The RV end-diastolic volume by GM showed wider limits of agreement. The RV end-systolic volume by GM was underestimated by around 10 ml compared to SAS. CONCLUSION: Both the visual estimate and the GM had similar bias and limits of agreement when compared to SAS. Though the end-systolic measurement is somewhat underestimated, the geometric method may be useful for serial volume measurements.  相似文献   

16.
Right ventricular (RV) dimensions and function are of diagnostic and prognostic importance in cardiac disease. Because of the peculiar morphology of the right ventricle, 2-dimensional echocardiography has several limitations in RV evaluation. Recently, new 3-dimensional transthoracic echocardiographic software adapted for RV morphology was introduced. The aims of this study were to evaluate the feasibility of 3-dimensional RV analysis in a large population and to compare and correlate 3-dimensional RV data with classic 2-dimensional and Doppler parameters, including tricuspid annular plane systolic excursion and peak systolic velocity on Doppler tissue imaging, RV fractional shortening area, RV stroke volume (by the Doppler method), and pulmonary arterial systolic pressure. Two hundred subjects were studied: 48 normal controls and 152 patients with valvular heart disease (104 patients), idiopathic dilated cardiomyopathy (20 patients), or pulmonary hypertension (28 patients). The mean times for 3-dimensional acquisition and 3-dimensional reconstruction were 3 +/- 1 and 4 +/- 2 minutes, respectively. Imaging quality was good in most cases (85%). The mean RV diastolic and systolic volumes were 103 +/- 38 and 46 +/- 28 ml, respectively. The RV ejection fraction (RVEF) was correlated negatively with pulmonary arterial systolic pressure and positively with tricuspid annular plane systolic excursion, peak systolic velocity, and fractional shortening area. The pathologic group was characterized by larger RV volumes and lower RVEFs. Three-dimensional echocardiography clearly showed that in the pathologic group, patients with pulmonary hypertension had the largest RV volumes and the lowest RVEFs and that those with idiopathic dilated cardiomyopathy were characterized by RVEFs lower than those of patients with valvular disease. In conclusion, this new quantitative 3-dimensional method to assess RV volumes and function is feasible, relatively simple, and not time consuming. Data obtained with 3-dimensional analysis are well correlated with those obtained by 2-dimensional and Doppler methods and can differentiate normal and pathologic subjects.  相似文献   

17.
While carbon monoxide (CO) intoxication often triggers multiple intraneuronal immune- or inflammatory-related cascades, it is not known whether the pathological processes within the affected regions evolve equally in the long term. To understand the neurodegenerative networks, we examined 49 patients with a clinical diagnosis of CO intoxication related to charcoal burning suicide at the chronic stage and compared them with 15 age- and sex-matched controls. Reconstructions of degenerative networks were performed using T1 magnetic resonance imaging, diffusion-tensor imaging, and fluorodeoxyglucose positron emission tomography (PET). Tract-specific fractional anisotropy (FA) quantification of 11 association fibers was performed while the clinical significance of the reconstructed structural or functional networks was determined by correlating them with the cognitive parameters. Compared with the controls, the patients had frontotemporal gray matter (GM) atrophy, diffuse white matter (WM) FA decrement, and axial diffusivity (AD) increment. The patients were further stratified into 3 groups based on the cognitive severities. The spatial extents within the frontal-insular-caudate GM as well as the prefrontal WM AD increment regions determined the cognitive severities among 3 groups. Meanwhile, the prefrontal WM FA values and PET signals also correlated significantly with the patient''s Mini-Mental State Examination score. Frontal hypometabolic patterns in PET analysis, even after adjusted for GM volume, were highly coherent to the GM atrophic regions, suggesting structural basis of functional alterations. Among the calculated major association bundles, only the anterior thalamic radiation FA values correlated significantly with all chosen cognitive scores. Our findings suggest that fronto-insular-caudate areas represent target degenerative network in CO intoxication. The topography that occurred at a cognitive severity-specific level at the chronic phase suggested the clinical roles of frontal areas. Although changes in FA are also diffusely distributed, different regional changes in AD suggested unequal long-term compensatory capacities among WM bundles. As such, the affected WM regions showing irreversible changes may exert adverse impacts to the interconnected GM structures.  相似文献   

18.
Patients with mitral valve prolapse (MVP) may develop severe mitral regurgitation (MR) and require valve surgery. Preliminary data suggest that high body weight and blood pressure might add to the irreversible factors of older age and male gender in increasing risk of these complications. Fifty-four patients with severe MR due to MVP were compared with 117 control subjects with uncomplicated MVP to elucidate factors independently associated with severe MR: the need for valve surgery and the cumulative risk of requiring mitral valve surgery. Patients with severe MR were older (p<0.00005), more overweight (p = 0.002), had higher systolic (p = 0.0003) and diastolic (p = 0.007) blood pressures, and were more likely to have hypertension (p = 0.0001) and to be men (p<0.001). In both groups, men had higher blood pressure and relative body weight than women. In multivariate analysis, older age was most strongly associated with MR; higher body mass index, hypertension, and gender were independent predictors of severe MR in analyses that excluded age. Among the 54 patients with severe MR, the 32 (59%) who underwent mitral valve surgery during 11 years of follow-up were older, more overweight, and more likely to be hypertensive than those not requiring surgery. Among patients undergoing mitral valve surgery in 3 centers, mitral prolapse was the etiology in 25%, 67% of whom were men. Using these data and national statistics, we estimate that the gender-specific cumulative risk for requiring valvular surgery for severe MR in subjects with MVP is 0.8% in women and 2.6% in men before age 65, and 1.4% and 5.5% by age 75. Thus, subjects with MVP who are older, more overweight, and hypertensive are at greater risk for severe MR and valve surgery. Higher blood pressure and relative weight in men with MVP appear to contribute to the gender difference in risk for severe MR.  相似文献   

19.
目的利用优化的基于体素的形态学研究方法,比较遗忘型轻度认知损害(aMCI)和轻度阿尔茨海默病(AD)患者脑灰质体积。方法选取aMCI患者9例(aMCl组)、轻度AD患者13例(AD组)和正常老年志愿者7例(对照组),经T_2加权像排除颅内存在白质高密度信号,对其进行高分辨率三维T_1加权像扫描,数据在参数统计软件包SPM5下进行头颅标准化、优化、分割和平滑等处理。结果 aMCI组的双侧颞上回、额中回、中央前回、扣带回、顶下小叶、左侧颞中回、中央后回、海马旁回、右侧岛回和旁中央小叶等结构灰质体积小于对照组,差异有统计学意义(P<0.01)。aMCI组的双侧颞上回、齿状回、额上回、额中回、岛回、左侧楔前叶、中央后回、右侧颞中回、颞下回、额下回、顶上小叶和海马旁回等结构灰质体积大于AD组,差异有统计学意义(P<0.01)。结论基于体素的形态学研究能够发现aMCI患者颞、顶、额叶均存在一定程度萎缩,其萎缩程度与累及范围均介于正常老人与轻度AD之间。  相似文献   

20.
Abstract

Background: Alcohol use in excessive quantities has deleterious effects on brain structure and behavior in adults and during periods of rapid neurodevelopment, such as prenatally. Whether similar outcomes characterize other developmental periods, such as adolescence, and in the context of less extensive use is unknown. Recent cross-sectional studies suggest that binge drinking as well as alcohol use disorders in adolescence are associated with disruptions in white matter microstructure and gray matter volumes. Objectives: The current study followed typically developing adolescents from a baseline assessment, where no experience with alcohol was present, through two years, after which some individuals transitioned into regular use. Methods: Participants (n?=?55) completed MRI scans and behavioral assessments. Results: Alcohol initiators (n?=?30; mean baseline age 16.7?±?1.3 years), compared to non-users (n?=?25; mean baseline age 17.1?±?1.2 years), showed altered patterns of neurodevelopment. They showed greater-than-expected decreases in cortical thickness in the right middle frontal gyrus from baseline to follow-up as well as blunted development of white matter in the right hemisphere precentral gyrus, lingual gyrus, middle temporal gyrus and anterior cingulate. Diffusion tensor imaging revealed a relative decrease over time in fractional anisotropy in the left caudate/thalamic region as well as in the right inferior frontal occipital fasciculus. Alcohol initiators did not differ from non-users at the baseline assessment; the groups were largely similar in other premorbid characteristics. Conclusions: Subclinical alcohol use during mid-to-late adolescence is associated with deviations in neurodevelopment across several brain tissue classes. Implications for continued development and behavior are discussed.  相似文献   

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