voxel-based morphometry Dotaz Zobrazit nápovědu
OBJECTIVE: The aim of the study was to assess structural changes in gray matter (GM) volume and fractional anisotropy (FA) in patients with Alzheimer's disease (AD) compared to control subjects using Voxel-Based Morphometry (VBM). Fractional anisotropy in the corpus callosum of both groups was also calculated using ROI analysis. METHODS: Twenty-one patients and twenty-three control subjects underwent MRI examination using T1-weighted 3D MPRAGE sequence and diffusion spin-echo echo-planar imaging sequence in six directions. Structural MRI analyses for GM volume and FA were performed using an optimized VBM protocol implemented in SPM5. The influence of age and Mini-Mental State Examination (MMSE) was dealt with multiple regression analysis either for the whole group or for AD patients and controls separately. RESULTS: Patients showed significant reduction of GM volume mainly in the temporal lobes. In AD patients, no correlation was observed between GM volume and age or MMSE. FA was reduced in AD patients mainly in frontal and temporal lobes. In both groups no correlation was found between FA and age or MMSE. Patients with AD showed a significant decrease in FA and an increase in mean diffusivity (p<0.0001) in the corpus callosum. CONCLUSIONS: In patients with AD we observed a significant reduction in FA values and GM volume; however, no correlation with age and MMSE was proven for both FA and GM for AD patients. This finding supports the hypothesis that morphological changes in patients with AD are not a continuous aging related process but represent qualitative changes.
- MeSH
- Alzheimerova nemoc diagnóza MeSH
- anizotropie MeSH
- corpus callosum diagnostické zobrazování patologie MeSH
- difuzní magnetická rezonance metody MeSH
- echoplanární zobrazování metody MeSH
- lidé středního věku MeSH
- lidé MeSH
- psychologické testy MeSH
- radiografie MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- věkové faktory MeSH
- velikost orgánu MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- klinické zkoušky kontrolované MeSH
- práce podpořená grantem MeSH
OBJECTIVES: To address the role of latent T. gondii infection in schizophrenia we studied the influence of latent toxoplasmosis on brain morphology. METHODS: An optimized voxel-based morphometry of magnetic resonance imaging was analyzed by analysis of variance with diagnosis and seropositivity as factors in 44 schizophrenic patients (12 T. gondii positive) and 56 controls (13 T. gondii positive). RESULTS: Grey matter (GM) volume was reduced in schizophrenia patients compared with controls in the cortical regions, hippocampus and in the caudate. In the schizophrenia sample we found a significant reduction of GM volume in T. gondii positive comparing with T. gondii-negative patients bilaterally in the caudate, median cingulate, thalamus and occipital cortex and in the left cerebellar hemispheres. T. gondii-positive and -negative controls did not differ in any cluster. Among participants seropositive to T. gondii the reduction of GM in the schizophrenia subjects was located in the same regions when comparing the entire sample (11,660 over-threshold voxels (P ≤ 0.05, FWR corrected). The differences between T. gondii-negative patients and controls consisted only of 289 voxels in temporal regions. CONCLUSIONS: Our study is the first to document that latent toxoplasmosis reduces GM in schizophrenia but not in controls.
- MeSH
- analýza rozptylu MeSH
- dospělí MeSH
- ELISA MeSH
- hipokampus mikrobiologie patologie MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- mapování mozku metody MeSH
- mozek mikrobiologie patologie MeSH
- mozková kůra mikrobiologie patologie MeSH
- mozková toxoplazmóza komplikace mikrobiologie patologie MeSH
- počítačové zpracování obrazu metody MeSH
- schizofrenie komplikace mikrobiologie patologie MeSH
- spánkový lalok mikrobiologie patologie MeSH
- thalamus mikrobiologie patologie MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
PURPOSE: : To assess whether structural and metabolic brain abnormalities are correlated in MTLE/HS syndrome. METHODS: : Optimized voxel-based morphometry (VBM) of gray matter concentration (GMC) and gray matter volume (GMV) and proton magnetic resonance spectroscopy measurements from both-sided hippocampal and thalamic regions were performed in 20 MTLE/HS patients and 20 sex- and age-matched healthy controls. The local GMC and GMV values were calculated in both the affected and unaffected hippocampi and ipsilateral and contralateral thalami in patients and healthy subjects, and these were compared. VBM variables and NAA, NAA/Cr and NAA/(Cr+Cho) values from the investigated brain regions were correlated. RESULTS: : (1) Analysis revealed significantly more extensive GMV reduction than GMC reduction in patients' affected hippocampus. In addition, significant GMV reduction was observed in the ipsilateral thalamus in MTLE/HS patients. (2) Significant decreases in all VBM and MRS variables were revealed in the affected hippocampus. Whilst practically normal GMC values were revealed in patients' both-sided thalamic regions, a significant decrease in local GMV and metabolic measurements were found in the patients' ipsilateral thalamus. (3) Pearson's correlations between structural and metabolic abnormalities were significant for the ipsilateral thalamus only. CONCLUSION: : Structural and metabolic abnormalities as detected by optimized voxel-based morphometry and (1)H MRS in hippocampal and thalamic regions are only partially correlated in MTLE/HS patients. It seems therefore reasonable that both methods reflect different aspects of brain pathology, which, at least to some degree, might be independently ongoing.
- MeSH
- audiovizuální záznam metody MeSH
- cholin metabolismus MeSH
- dospělí MeSH
- elektroencefalografie metody MeSH
- epilepsie temporálního laloku patologie MeSH
- hipokampus patologie MeSH
- kreatin metabolismus MeSH
- kyselina asparagová analogy a deriváty metabolismus MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční spektroskopie metody MeSH
- magnetická rezonanční tomografie metody MeSH
- mapování mozku MeSH
- mladiství MeSH
- mladý dospělý MeSH
- počítačové zpracování obrazu MeSH
- protony MeSH
- skleróza patologie MeSH
- statistika jako téma MeSH
- studie případů a kontrol MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- cholin MeSH
- kreatin MeSH
- kyselina asparagová MeSH
- N-acetylaspartate MeSH Prohlížeč
- protony MeSH
PURPOSE: To determine whether voxel-based morphometry (VBM) might contribute to the detection of cortical dysplasia within the temporal pole in patients with mesial temporal lobe epilepsy and hippocampal sclerosis (MTLE/HS). METHODS: Eighteen patients with intractable MTLE/HS and 30 sex- and age-matched healthy controls were included in the study. All of the patients fulfilled the diagnostic criteria for MTLE/HS and underwent anteromedial temporal resection. VBM without a modulation step was applied to the magnetic resonance (MR) images of the brain. Statistical parametric maps were used to compare structural characteristics such as gray matter concentration (GMC) within the temporal pole among patients and controls separately. The acquired data were then statistically analyzed to determine the congruency between visually inspected MR imaging (MRI) scans and VBM results in the detection of morphologic abnormalities in the temporal pole compared to postoperative histopathologic findings of cortical dysplasia. KEY FINDINGS: Histopathologic examination revealed cortical dysplasia within the temporal pole in 11 patients. In detail, according to Palmini's classification, mild malformations of cortical development (mMCDs) were disclosed in three patients, focal cortical dysplasia (FCD) type Ia in three patients, and FCD type Ib in five patients. Some type of structural temporal pole abnormality was suggested by VBM in 14 patients and by visually inspected MRI scans in 11 patients. The results of VBM were in agreement with the presence/absence of cortical dysplasia in 13 patients (72.2%); this correspondence was significant (p = 0.047). In one case, VBM was false negative and in four cases it was false positive. There was congruence between the results of visual analysis and histologic proof in 55.6% of examined patients, which was not significant. SIGNIFICANCE: We found that VBM made a superior contribution to the detection of temporopolar structural malformations (cortical dysplasia) compared to visual inspection. The agreement with postoperative histopathologic proof was clearly significant for VBM results and nonsignificant for visual inspection.
- MeSH
- analýza rozptylu MeSH
- diplopie diagnóza etiologie MeSH
- dospělí MeSH
- epilepsie temporálního laloku komplikace diagnóza MeSH
- funkční lateralita MeSH
- hipokampus patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie * MeSH
- mapování mozku MeSH
- mladý dospělý MeSH
- počítačové zpracování obrazu MeSH
- spánkový lalok patologie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Schizophrenia is a severe neuropsychiatric disease whose diagnosis, unfortunately, lacks an objective diagnostic tool supporting a thorough psychiatric examination of the patient. We took advantage of today's computational abilities, structural magnetic resonance imaging, and modern machine learning methods, such as stacked autoencoders (SAE) and 3D convolutional neural networks (3D CNN), to teach them to classify 52 patients with schizophrenia and 52 healthy controls. The main aim of this study was to explore whether complex feature extraction methods can help improve the accuracy of deep learning-based classifiers compared to minimally preprocessed data. Our experiments employed three commonly used preprocessing steps to extract three different feature types. They included voxel-based morphometry, deformation-based morphometry, and simple spatial normalization of brain tissue. In addition to classifier models, features and their combination, other model parameters such as network depth, number of neurons, number of convolutional filters, and input data size were also investigated. Autoencoders were trained on feature pools of 1000 and 5000 voxels selected by Mann-Whitney tests, and 3D CNNs were trained on whole images. The most successful model architecture (autoencoders) achieved the highest average accuracy of 69.62% (sensitivity 68.85%, specificity 70.38%). The results of all experiments were statistically compared (the Mann-Whitney test). In conclusion, SAE outperformed 3D CNN, while preprocessing using VBM helped SAE improve the results.
- Klíčová slova
- 3D CNN, autoencoders, classification, deep learning, deformation-based morphometry, schizophrenia, voxel-based morphometry,
- Publikační typ
- časopisecké články MeSH
Wilson disease (WD) primarily presents with hepatic and neurological symptoms. While hepatic symptoms typically precede the neurological manifestations, copper accumulates in the brain already in this patient group and leads to subclinical brain MRI abnormalities including T2 hyperintensities and atrophy. This study aimed to assess brain morphological changes in mild hepatic WD. WD patients without a history of neurologic symptoms and decompensated cirrhosis and control participants underwent brain MRI at 3T scanner including high-resolution T1-weighted images. A volumetric evaluation was conducted on the following brain regions: nucleus accumbens, caudate, pallidum, putamen, thalamus, amygdala, hippocampus, midbrain, pons, cerebellar gray matter, white matter (WM), and superior peduncle, using Freesurfer v7 software. Whole-brain analyses using voxel- and surface-based morphometry were performed using SPM12. Statistical comparisons utilized a general linear model adjusted for total intracranial volume, age, and sex. Twenty-six WD patients with mild hepatic form (30 ± 9 years [mean age ± SD]); 11 women; mean treatment duration 13 ± 12 (range 0-42) years and 28 healthy controls (33 ± 9 years; 15 women) were evaluated. Volumetric analysis revealed a significantly smaller pons volume and a trend for smaller midbrain and cerebellar WM in WD patients compared to controls. Whole-brain analysis revealed regions of reduced volume in the pons, cerebellar, and lobar WM in the WD group. No significant differences in gray matter density or cortical thickness were found. Myelin or WM in general seems vulnerable to low-level copper toxicity, with WM volume loss showing promise as a marker for assessing brain involvement in early WD stages.
- Klíčová slova
- MRI, Wilson disease, brain atrophy, brainstem, hepatic, morphometry, white matter,
- MeSH
- bílá hmota patologie diagnostické zobrazování MeSH
- dospělí MeSH
- hepatolentikulární degenerace * patologie diagnostické zobrazování MeSH
- játra patologie diagnostické zobrazování MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie * MeSH
- mladý dospělý MeSH
- mozek * patologie diagnostické zobrazování MeSH
- šedá hmota patologie diagnostické zobrazování MeSH
- studie případů a kontrol MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
To identify progressive supranuclear palsy (PSP), we combined voxel-based morphometry (VBM) and support vector machine (SVM) classification using disease-specific features in multicentric magnetic resonance imaging (MRI) data. Structural brain differences were investigated at four centers between 20 patients with PSP and 20 age-matched healthy controls with T1-weighted MRI at 3T. To pave the way for future application in personalized medicine, we applied SVM classification to identify PSP on an individual level besides group analyses based on VBM. We found a major decline in gray matter density in the brainstem, insula, and striatum, and also in frontomedian regions, which is in line with current literature. Moreover, SVM classification yielded high accuracy rates above 80% for disease identification in imaging data. Focusing analyses on disease-specific regions-of-interest (ROI) led to higher accuracy rates compared to a whole-brain approach. Using a polynomial kernel (instead of a linear kernel) led to an increased sensitivity and a higher specificity of disease detection. Our study supports the application of MRI for individual diagnosis of PSP, if combined with SVM approaches. We demonstrate that SVM classification provides high accuracy rates in multicentric data-a prerequisite for potential application in diagnostic routine.
- Klíčová slova
- atypical parkinsonism, magnetic resonance imaging, progressive supranuclear palsy, support vector machine classification, voxel-based morphometry,
- Publikační typ
- časopisecké články MeSH
BACKGROUND: Neurostructural alterations are often reported in first episode of psychosis (FEP), but there is heterogeneity in the direction and location of findings between individual studies. The reasons for this heterogeneity remain unknown. Obesity is disproportionately frequent already early in the course of psychosis and is associated with smaller brain volumes. Thus, we hypothesized that obesity may contribute to brain changes in FEP. METHOD: We analyzed MRI scans from 120 participants with FEP and 114 healthy participants. In primary analyses, we performed voxel-based morphometry (VBM) with small volume corrections to regions associated with FEP or obesity in previous meta-analyses. In secondary analyses, we performed whole-brain VBM analyses. RESULTS: In primary analyses, we found that when controlling for BMI, FEP had lower GM volume than healthy participants in a) left fronto-temporal region (pTFCE = 0.008) and b) left postcentral gyrus (pTFCE = 0.043). When controlling for FEP, BMI was associated with lower GM volume in left cerebellum (pTFCE < 0.001). In secondary analyses, we found that when controlling for BMI, FEP had lower GM volume than healthy participants in the a) cerebellum (pTFCE = 0.004), b) left frontal (pTFCE = 0.024), and c) right temporal cortex (pTFCE = 0.031). When controlling for FEP, BMI was associated with lower GM volume in cerebellum (pTFCE = 0.004). Levels of C-reactive protein, HDL and LDL-cholesterol correlated with obesity related neurostructural alterations. CONCLUSIONS: This study suggests that higher BMI, which is frequent in FEP, may contribute to cerebellar alterations in schizophrenia. As previous studies showed that obesity-related brain alterations may be reversible, our findings raise the possibility that improving the screening for and treatment of obesity and associated metabolic changes could preserve brain structure in FEP.
- Klíčová slova
- dyslipidemia, first-episode psychosis, low-grade inflammation, obesity, schizophrenia, voxel-based morphometry,
- Publikační typ
- časopisecké články MeSH
OBJECTIVES: There is a lot of variability between the results of studies reporting the pattern of gray matter volume changes in schizophrenia. Methodological issues may play an important role in this heterogeneity. The aim of the present study was to replicate the better performance of multivariate "source-based morphometry" (SBM) over the mass-univariate approach. EXPERIMENTAL DESIGN: Voxel-based morphometry of Jacobian-modulated gray matter volume images, using voxel and cluster level inference, and SBM were performed in a group of first-episode schizophrenia patients (N = 49) and healthy controls (N = 127). RESULTS: Using SBM we were able to find a significant reduction of gray matter volume in fronto-temporo-cerebellar areas whereas no significant results were obtained using voxel-based morphometry. CONCLUSION: Multivariate analysis of gray matter volume seems to be a suitable method for characterization of the pattern of changes at the beginning of the illness in schizophrenia subjects.
- MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody MeSH
- mladý dospělý MeSH
- mozek patologie MeSH
- multivariační analýza MeSH
- nervová vlákna nemyelinizovaná patologie MeSH
- počítačové zpracování obrazu metody MeSH
- schizofrenie patologie MeSH
- velikost orgánu MeSH
- Check Tag
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Introduction: Recent studies of patients with multiple sclerosis (MS) have revealed disturbances in distinct components of social cognition, such as impaired mentalizing and empathy. The present study investigated this socio-cognitive profile in MS patients in more detail, by examining their performance on tasks measuring more fundamental components of social cognition and any associated disruptions to gray-matter volume (GMV). Methods: We compared 43 patients with relapse-remitting MS with 43 age- and sex-matched healthy controls (HCs) on clinical characteristics (depression, fatigue), cognitive processing speed, and three aspects of low-level social cognition; specifically, imitative tendencies, visual perspective taking, and emotion recognition. Using voxel-based morphometry, we then explored relationships between GMV and these clinical and behavioral measures. Results: Patients exhibited significantly slower processing speed, poorer perspective taking, and less imitation compared with HCs. These impairments were related to reduced GMV throughout the putamen, thalami, and anterior insula, predominantly in the left hemisphere. Surprisingly, differences between the groups in emotion recognition were not significant. Conclusion: Less imitation and poorer perspective taking indicate a cognitive self-bias when faced with conflicting self- and other-representations. This suggests that impaired self-other distinction, and an associated subcortical pattern of GM atrophy, might underlie the socio-cognitive disturbances observed in MS.
- Klíčová slova
- automatic imitation, gray-matter volume, multiple sclerosis, self-other distinction, social cognition, visual perspective taking, voxel-based morphometry,
- Publikační typ
- časopisecké články MeSH