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1.
Cardiovasc Intervent Radiol ; 33(6): 1243-52, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20155357

RESUMO

This study was designed to confirm relationships between decrease of bone mineral density and increase of marrow fat and to delineate, through MR spectroscopy, vertebral body at high risk for compression fracture onset to justify prophylactic vertebroplasty. We enrolled 127 women: 48 osteoporotic, 36 osteopenic, and 43 normal subjects, who underwent DXA and MR examination of spine. Then, we selected 48 patients with at least two acute osteoporotic vertebral fractures with interposed normal "sandwich" vertebrae; all patients underwent MR examination of spine. Significant statistical differences were found among "Fat Fraction" (FF) values in normal, osteopenic, and osteoporotic subjects: 59.8 ± 5.1%; 64.8 ± 4.4%; and 67.1 ± 3.3%. A mild, significant, negative correlation was observed between T-score and vertebral fat content (r = - 0.585; P = 0.0000). In the second part of the study, 9 new vertebral fractures were observed in 48 patients (19%): 6 were "sandwich" vertebrae (12.5%), and 3 were located in distant vertebral body. The mean FF in sandwich fractured vertebrae was 72.75 ± 1.95 compared with the FF of the nonfractured sandwich, and distant control vertebrae were 61.83 ± 3.42 and 61.42 ± 3.64. We found a significant statistical difference between fractured and nonfractured vertebrae (P < 0.001). The results of this study suggest that MR spectroscopy could be a reliable index to predict the risk of new compression vertebral fracture and could be used for vertebroplasty planning contributing to clarify the possibility to add prophylactic PVP to standard treatment.


Assuntos
Fraturas por Compressão/prevenção & controle , Espectroscopia de Ressonância Magnética/métodos , Fraturas da Coluna Vertebral/prevenção & controle , Vertebroplastia/métodos , Absorciometria de Fóton , Idoso , Densidade Óssea , Doenças Ósseas Metabólicas/complicações , Feminino , Fraturas por Compressão/etiologia , Humanos , Osteoporose/complicações , Valor Preditivo dos Testes , Estudos Prospectivos , Fraturas da Coluna Vertebral/etiologia
2.
Eur J Neurol ; 16(11): 1185-90, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19538216

RESUMO

BACKGROUND AND PURPOSE: It has been proposed that white matter alterations might play a role in autistic disorders; however, published data are mainly limited to high-functioning autism. The goal of this study was to apply diffusion tensor imaging (DTI) and fiber tractography (FT) to study white matter in low-functioning autism and the relationship between white matter and cognitive impairment. METHODS: Ten low-functioning males with autism (mean age: 19.7 +/- 2.83 years) and 10 age-matched healthy males (mean age: 19.9 +/- 2.64 years) underwent DTI-MRI scanning. fractional anisotropy (FA) maps were analyzed with whole brain voxel-wise and tract-of-interest statistics. Using FT algorithms, white matter tracts connecting the orbitofrontal cortex (OFC) with other brain regions were identified and compared between the two groups. FA mean values of the autistic group were correlated with intelligence quotient (IQ) scores. RESULTS: Low-functioning autistic subjects showed a reduced tract volume and lower mean FA values in the left OFC network compared with controls. In the autistic group, lower FA values were associated with lower IQ scores. CONCLUSIONS: We showed evidence of OFC white matter network abnormalities in low-functioning autistic individuals. Our results point to a relationship between the severity of the intellectual impairment and the extent of white matter alterations.


Assuntos
Transtorno Autístico/patologia , Encéfalo/patologia , Deficiência Intelectual/patologia , Fibras Nervosas Mielinizadas/patologia , Adolescente , Adulto , Algoritmos , Anisotropia , Mapeamento Encefálico , Imagem de Tensor de Difusão , Humanos , Processamento de Imagem Assistida por Computador , Testes de Inteligência , Masculino , Vias Neurais/patologia , Testes Neuropsicológicos , Estatísticas não Paramétricas
3.
Int J Neurosci ; 119(4): 531-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19229720

RESUMO

Magnetic Resonance Imaging (MRI) represents the procedure of choice for detection of anatomical lesions in epilepsy. Vascular malformations in central nervous system, such as cavernoma, can cause symptomatic epilepsy. We describe a case of ictal aphasia as manifestation of a partial status epilepticus probably due to a mutual interaction between a recent bleeding cavernoma and a concomitant reduction of antiepileptic treatment in a long-lasting misdiagnosed symptomatic epilepsy. We conclude that MRI is a mandatory diagnostic method to identify structural abnormalities underlying epilepsy in all patients affected by recurrent focal seizures independent of the duration of epilepsy.


Assuntos
Afasia/etiologia , Estado Epiléptico/complicações , Estado Epiléptico/diagnóstico , Anticonvulsivantes/uso terapêutico , Encéfalo/patologia , Carbamazepina/uso terapêutico , Eletroencefalografia , Humanos , Lorazepam/uso terapêutico , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/patologia
4.
AJNR Am J Neuroradiol ; 28(3): 475-8, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17353315

RESUMO

BACKGROUND AND PURPOSE: Our aim was to evaluate the hypothesis that water diffusion alterations are present in normal-appearing white matter of patients with relapsing-remitting multiple sclerosis (RRMS) and to assess their change with time. MATERIALS AND METHODS: Fifty-four subjects with clinically diagnosed RRMS, with disease duration of less than 12 months and an expanded disability status scale (EDSS) score of <3.5, underwent a diffusion 3T MR imaging study. The apparent diffusion coefficient (ADC) maps generated were compared with those of 18 control subjects. Eighteen of the 54 patients underwent MR imaging assessment at 3 and 6 months after baseline evaluation. Remitting patients were clinically and MR imaging stable for the 2 months before the study. All patients were drug-free for the 3 months before the study, and in the relapsing patients, the MR imaging was always performed before beginning treatment. RESULTS: Mean ADC values showed significant differences when relapsing, remitting, and control patients were compared. The relapsing or remitting phase showed significant difference when compared both with controls (P < .01) and between them (P < .05). Comparing mean ADC values of patients with clinical disability (EDSS <2 versus EDSS >/=2) also provided significant differences with the control group (P < .01). The data of patients showing a relapsing episode during the longitudinal part of the study showed a significant difference compared with data from their remitting phase (P < .01). CONCLUSION: Brain microstructural changes can be detected and correlate with clinical impairment during the stages of MS. These changes modify with time in the relapsing group.


Assuntos
Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética , Esclerose Múltipla Recidivante-Remitente/patologia , Fibras Nervosas Mielinizadas/patologia , Adolescente , Adulto , Avaliação da Deficiência , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Recidiva
5.
Radiol Med ; 112(2): 208-23, 2007 Mar.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-17361375

RESUMO

PURPOSE: This study was undertaken to evaluate the diagnostic capabilities of 3-Tesla (T) magnetic resonance (MR) in vertebral osteoporosis. MATERIALS AND METHODS: Thirty subjects (ten healthy controls, ten with osteoporosis but no fracture, ten with osteoporotic vertebral fractures) underwent MR of the lumbar spine. Turbo spin echo (TSE) T1-, T2- and T2- spectral selection attenuated inversion recovery (SPAIR) weighted imaging and spectroscopy for the selective evaluation of water and fat content were performed. The apparent diffusion coefficient (ADC) was calculated, and diffusion tensor imaging (DTI) was performed to create a map of the spatial arrangement of the tissue structures. RESULTS: Morphological imaging detected recent vertebral fractures. In osteoporotic patients, spectroscopic imaging demonstrated an increase in the saturated fats and a decrease in the ADC, whereas the data provided by DTI demonstrated a bone structure with medium-degree anisotropy. DISCUSSION: Osteoporosis is characterised by trabecular thinning, with an increase in the intertrabecular spaces, which are filled with fats. The anisotropic study and the subsequent assessment of colour and vector maps can provide a noninvasive tool for assessing the risk of fracture due to osteoporosis.


Assuntos
Vértebras Lombares/patologia , Imageamento por Ressonância Magnética/métodos , Osteoporose/patologia , Fraturas da Coluna Vertebral/patologia , Adulto , Idoso , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Fraturas da Coluna Vertebral/etiologia
6.
Radiol Med ; 111(2): 284-90, 2006 Mar.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-16671385

RESUMO

PURPOSE: The aim of our study was to assess the regional cerebral blood flow (rCBF) of basal ganglia and thalami in patients with Parkinson's disease (PD) using perfusion-weighted magnetic resonance imaging (PW-MRI). MATERIAL AND METHODS: Twenty subjects affected by idiopathic PD according to the United Kingdom Brain Bank criteria were enrolled in the study. Twenty normal subjects matched for age and gender were included as controls. After 20-day therapy withdrawal, the PD patients underwent PW-MRI. The rCBF was calculated both in patients and in controls. The regions of interest were manually positioned on rCBF maps over the caudate nucleus, the putamen, the external and internal globus pallidus, and over the ventrolateral nucleus of the thalamus. Data were normalised with those obtained from parieto-occipital white matter (POWM). Statistical analysis was performed using a parametric ANOVA test. RESULTS: Patients showed a significant (p<0.01) interhemispheric asymmetry; rCBF values were higher on the more severely affected side. Controls showed no interhemispheric asymmetry. CONCLUSION: Our study suggests that PW-MRI is a valuable tool for assessing haemodynamic changes in PD patients. Haemodynamic change pattern may be useful in the early diagnosis of PD.


Assuntos
Gânglios da Base/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/fisiopatologia , Idoso , Estudos de Casos e Controles , Núcleo Caudado/irrigação sanguínea , Meios de Contraste , Feminino , Gadolínio DTPA , Globo Pálido/irrigação sanguínea , Humanos , Aumento da Imagem/métodos , Masculino , Lobo Occipital/irrigação sanguínea , Lobo Parietal/irrigação sanguínea , Putamen/irrigação sanguínea , Tálamo/irrigação sanguínea , Núcleos Ventrais do Tálamo/irrigação sanguínea
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