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1.
Respiration ; 94(6): 510-517, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29020669

RESUMO

BACKGROUND: Inhabitants of Metsovo, NW Greece, had been domestically exposed to asbestos from a gradually abandoned whitewash ("luto") that resulted in a declining epidemic of malignant mesothelioma. OBJECTIVES: We aimed to evaluate whether other sources of asbestos exposure exist following "luto" abandonment. METHODS: Chest computed tomography (CT) and bronchoalveolar lavage (BAL) were used to evaluate residual asbestos exposure in younger Metsovites through the identification of pleural calcifications and asbestos bodies, respectively. In order to provide a historical universally exposed group for comparison, we used the accumulated chest CTs and chest roentgenograms of our previous studies, performed in Metsovites with confirmed exposure but negative chest roentgenogram. As an additional external comparison group, we also assessed CT scans and chest roentgenograms of Metsovites being older than our target group obtained from the records of the Radiology Department between 2009 and 2011. In order to be able to compare our BAL findings, we sought historical controls among BAL studies performed in Metsovites with known exposure to "luto," in the 1980s-1990s, mainly to evaluate alveolitis. Those belonging to individuals of the same age range were used for further comparison. RESULTS: Twenty-two Metsovites born between 1960 and 1980 consented to undergo a chest CT scan, while another 14 CTs were retrieved from the records of the Radiology Department (among 86 of all ages), thus increasing the number of individuals studied to 36. Five of the 36 Metsovites studied were former "luto" users for a short period of time. Minimal pleural calcifications were present in 2 of them, while all chest CTs of nonusers were negative. All 8 BAL studies were negative for asbestos bodies. CONCLUSION: "Luto" use seems to have been the only source of considerable asbestos exposure in Metsovo.


Assuntos
Amianto/análise , Asbestose/diagnóstico por imagem , Calcinose/etiologia , Exposição Ambiental/análise , Adulto , Amianto/efeitos adversos , Líquido da Lavagem Broncoalveolar/química , Calcinose/diagnóstico por imagem , Exposição Ambiental/efeitos adversos , Feminino , Grécia/epidemiologia , Humanos , Masculino , Mesotelioma/epidemiologia , Mesotelioma/etiologia , Pessoa de Meia-Idade , Radiografia Torácica , Tomografia Computadorizada por Raios X
2.
Pediatr Radiol ; 47(5): 599-605, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28255689

RESUMO

BACKGROUND: In anterior pituitary deficiency, patients with non visible pituitary stalk have more often multiple deficiencies and persistent deficiency than patients with visible pituitary stalk. OBJECTIVE: To compare the diagnostic value of a high-resolution heavily T2-weighted sequence to 1.5-mm-thick unenhanced and contrast-enhanced sagittal T1-weighted sequences to assess the presence of the pituitary stalk in children with ectopic posterior pituitary gland. MATERIALS AND METHODS: We retrospectively evaluated the MRI data of 14 children diagnosed with ectopic posterior pituitary gland between 2010 and 2014. We evaluated the presence of a pituitary stalk using a sagittal high-resolution heavily T2-weighted sequence and a 1.5-mm sagittal T1-weighted turbo spin-echo sequence before and after contrast medium administration. RESULTS: A pituitary stalk was present on at least one of the sequences in 10 of the 14 children (71%). T2-weighted sequence depicted the pituitary stalk in all 10 children, whereas the 1.5-mm-thick T1-weighted sequence depicted 2/10 (20%) before contrast injection and 8/10 (80%) after contrast injection (P=0.007). CONCLUSION: Compared with 1.5-mm-thick contrast-enhanced T1-weighted sequences, high-resolution heavily T2-weighted sequence demonstrates better sensitivity in detecting the pituitary stalk in children with ectopic posterior pituitary gland, suggesting that contrast injection is unnecessary to assess the presence of a pituitary stalk in this setting.


Assuntos
Imageamento por Ressonância Magnética/métodos , Doenças da Hipófise/diagnóstico por imagem , Neuro-Hipófise/anormalidades , Neuro-Hipófise/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Lactente , Masculino , Meglumina , Compostos Organometálicos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
3.
Pediatr Radiol ; 46(8): 1158-64, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27085522

RESUMO

BACKGROUND: There is evidence of microstructural changes in normal-appearing white matter of patients with tuberous sclerosis complex. OBJECTIVE: To evaluate major white matter tracts in children with tuberous sclerosis complex using tract-based spatial statistics diffusion tensor imaging (DTI) analysis. MATERIALS AND METHODS: Eight children (mean age ± standard deviation: 8.5 ± 5.5 years) with an established diagnosis of tuberous sclerosis complex and 8 age-matched controls were studied. The imaging protocol consisted of T1-weighted high-resolution 3-D spoiled gradient-echo sequence and a spin-echo, echo-planar diffusion-weighted sequence. Differences in the diffusion indices were evaluated using tract-based spatial statistics. RESULTS: Tract-based spatial statistics showed increased axial diffusivity in the children with tuberous sclerosis complex in the superior and anterior corona radiata, the superior longitudinal fascicle, the inferior fronto-occipital fascicle, the uncinate fascicle and the anterior thalamic radiation. No significant differences were observed in fractional anisotropy, mean diffusivity and radial diffusivity between patients and control subjects. No difference was found in the diffusion indices between the baseline and follow-up examination in the patient group. CONCLUSION: Patients with tuberous sclerosis complex have increased axial diffusivity in major white matter tracts, probably related to reduced axonal integrity.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imagem de Tensor de Difusão , Esclerose Tuberosa/patologia , Substância Branca/patologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Retrospectivos , Esclerose Tuberosa/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
4.
Int J Neurosci ; 126(5): 422-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26000811

RESUMO

PURPOSE OF THE STUDY: The multimodal imaging investigation of excessive daytime sleepiness (EDS) in Parkinson's disease (PD). The role of dopaminergic treatment and other clinical parameters was also evaluated. MATERIALS AND METHODS: Seventeen non-demented PD patients with EDS (PD-EDS) and 17 PD patients without EDS were enrolled. Clinical, treatment and MRI data were acquired. Gray matter (GM) volume was examined with voxel-based morphometry, while white matter (WM) integrity was assessed with diffusion tensor imaging by means of fractional anisotropy, mean diffusivity, axial diffusivity (AD) and radial diffusivity measures. RESULTS: Increased regional GM volume was found in the PD-EDS group bilaterally in the hippocampus and parahippocampal gyri. Increased AD values were also shown in the PD-EDS group, in the left anterior thalamic radiation and the corticospinal tract and bilaterally in the superior corona radiata and the superior longitudinal fasciculus. Levodopa equivalent dose differed significantly between the groups and was the only predictor of EDS, while the only predictor of the Epworth sleepiness scale score in the PD-EDS group was the dopamine-agonist dose. Increased frequency of gamblers was also observed in the PD-EDS group. CONCLUSIONS: Regional GM increases and increased AD values in certain WM tracts were found in the PD-EDS group. The changes could result from disinhibited signaling pathways or represent compensatory changes in response to anatomical or functional deficits elsewhere. The study findings support also the contribution of the total dopaminergic load in the development of EDS, while the dose of dopamine agonists was found to predict the severity of the disorder.


Assuntos
Encéfalo/fisiopatologia , Distúrbios do Sono por Sonolência Excessiva/complicações , Doença de Parkinson/complicações , Idoso , Encéfalo/patologia , Imagem de Tensor de Difusão , Distúrbios do Sono por Sonolência Excessiva/patologia , Distúrbios do Sono por Sonolência Excessiva/fisiopatologia , Feminino , Substância Cinzenta/patologia , Substância Cinzenta/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Imagem Multimodal , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Substância Branca/patologia , Substância Branca/fisiopatologia
5.
Eur Radiol ; 24(10): 2499-506, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25001084

RESUMO

OBJECTIVES: To investigate structural brain changes in inflammatory bowel disease (IBD). METHODS: Brain magnetic resonance imaging (MRI) was performed on 18 IBD patients (aged 45.16 ± 14.71 years) and 20 aged-matched control subjects. The imaging protocol consisted of a sagittal-FLAIR, a T1-weighted high-resolution three-dimensional spoiled gradient-echo sequence, and a multisession spin-echo echo-planar diffusion-weighted sequence. Differences between patients and controls in brain volume and diffusion indices were evaluated using the voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) methods, respectively. The presence of white-matter hyperintensities (WMHIs) was evaluated on FLAIR images. RESULTS: VBM revealed decreased grey matter (GM) volume in patients in the fusiform and the inferior temporal gyrus bilaterally, the right precentral gyrus, the right supplementary motor area, the right middle frontal gyrus and the left superior parietal gyrus (p < 0.05). TBSS showed decreased axial diffusivity (AD) in the right corticospinal tract and the right superior longitudinal fasciculus in patients compared with controls. A larger number of WMHIs was observed in patients (p < 0.05). CONCLUSIONS: Patients with IBD show an increase in WMHIs and GM atrophy, probably related to cerebral vasculitis and ischaemia. Decreased AD in major white matter tracts could be a secondary phenomenon, representing Wallerian degeneration. KEY POINTS: • There is evidence of central nervous system involvement in IBD. • Diffusion tensor imaging detects microstructural brain abnormalities in IBD. • Voxel based morphometry reveals brain atrophy in IBD.


Assuntos
Encefalopatias/diagnóstico , Encéfalo/patologia , Imagem de Tensor de Difusão/métodos , Doenças Inflamatórias Intestinais/complicações , Imageamento por Ressonância Magnética/métodos , Atrofia/diagnóstico , Atrofia/etiologia , Encefalopatias/etiologia , Tronco Encefálico/patologia , Feminino , Seguimentos , Lobo Frontal/patologia , Humanos , Doenças Inflamatórias Intestinais/diagnóstico , Masculino , Pessoa de Meia-Idade , Lobo Parietal/patologia , Tratos Piramidais/patologia , Curva ROC , Lobo Temporal/patologia , Substância Branca/patologia
6.
Pediatr Radiol ; 44(3): 297-304, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24190757

RESUMO

BACKGROUND: Prematurity and intrauterine growth restriction are associated with neurodevelopmental disabilities. OBJECTIVE: To assess the relationship between growth status and regional brain volume (rBV) and white matter microstructure in premature babies at around term-equivalent age. MATERIALS AND METHODS: Premature infants (n= 27) of gestational age (GA): 29.8 ± 2.1 weeks, with normal brain MRI scans were studied at corrected age: 41.2 ± 1.4 weeks. The infants were divided into three groups: 1) appropriate for GA at birth and at the time of MRI (AGA), 2) small for GA at birth with catch-up growth at the time of MRI (SGAa) and 3) small for GA at birth with failure of catch-up growth at the time of MRI (SGAb). The T1-weighted images were segmented into 90 rBVs using the SPM8/IBASPM and differences among groups were assessed. Fractional anisotropy (FA) was measured bilaterally in 15 fiber tracts and its relationship to GA and somatometric measurements was explored. RESULTS: Lower rBV was observed in SGAb in superior and anterior brain areas. A positive correlation was demonstrated between FA and head circumference and body weight. Body weight was the only significant predictor for FA (P< 0.05). CONCLUSION: In premature babies, catch-up growth is associated with regional brain volume catch-up at around term-equivalent age, starting from the brain areas maturing first. Body weight seems to be a strong predictor associated with WM microstructure in brain areas related to attention, language, cognition, memory and executing functioning.


Assuntos
Tamanho Corporal/fisiologia , Encéfalo/anatomia & histologia , Encéfalo/crescimento & desenvolvimento , Recém-Nascido Prematuro/crescimento & desenvolvimento , Recém-Nascido Pequeno para a Idade Gestacional/crescimento & desenvolvimento , Imageamento por Ressonância Magnética/métodos , Feminino , Humanos , Recém-Nascido , Masculino , Tamanho do Órgão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
AJR Am J Roentgenol ; 197(5): 1207-12, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22021516

RESUMO

OBJECTIVE: The purpose of this study was to evaluate with MRI the involvement of gray matter and white matter structures in patients with primary Sjögren syndrome. SUBJECTS AND METHODS: Fifty-three patients with primary Sjögren syndrome, 18 age- and disease duration-matched patients with systemic sclerosis, and 35 age-matched control subjects were examined for differences in white matter hyperintensities (WMHIs) detected on FLAIR MR images. Differences in brain volume between patients with primary Sjögren syndrome and controls were studied by application of voxel-based morphometry to a 3D T1-weighted sequence. RESULTS: WMHIs were observed in 38 of the 53 patients with primary Sjögren syndrome, six of 18 patients with systemic sclerosis, and 17 of 35 controls. The numbers of WMHIs 2 mm or larger and the number smaller than 2 mm were higher in patients with primary Sjögren syndrome than in controls (≥ 2 mm, p = 0.004; < 2 mm, p < 0.001). No significant difference was observed in the number of WMHIs in primary Sjögren syndrome patients and that in systemic sclerosis patients. After control for age, a positive relation was found between disease duration and total number of WMHIs (p = 0.037) and number of WMHIs 2 mm or larger (p = 0.023) in patients with primary Sjögren syndrome. In comparison with the controls, patients with primary Sjögren syndrome had decreased gray matter volume in the cortex, deep gray matter, and cerebellum. Associated loss of white matter volume was observed in areas corresponding to gray matter atrophy and in the corpus callosum (p < 0.05). CONCLUSION: Patients with primary Sjögren syndrome have WMHIs and gray and white matter atrophy, probably related to cerebral vasculitis.


Assuntos
Encefalopatias/patologia , Imageamento por Ressonância Magnética/métodos , Fibras Nervosas/patologia , Síndrome de Sjogren/patologia , Adulto , Idoso , Mapeamento Encefálico , Estudos de Casos e Controles , Distribuição de Qui-Quadrado , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas
8.
Pediatr Radiol ; 39(12): 1327-32, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19789862

RESUMO

BACKGROUND: Brain plasticity in patients with periventricular leukomalacia (PVL) may suggest grey matter (GM) changes. OBJECTIVE: To assess the volume of 116 GM areas and total volume of GM, white matter (WM) and cerebrospinal fluid (CSF) in preterm children with PVL, using the Statistical Parametric Mapping (SPM5) and the Individual Brain Atlases Statistical Parametric Mapping (IBASPM) toolboxes. MATERIALS AND METHODS: Ten preterm children (gestational age 31.7 +/- 4.2 weeks, corrected age 27.8 +/- 21.7 months) with PVL and 46 matched, preterm control subjects were studied using a three-dimensional T1-weighted sequence. Volumes were calculated using SPM5 and IBASPM. RESULTS: GM volume in frontal superior orbital, posterior cingulum and lingual gyrus, the putamen and thalamus was significantly higher in children with PVL (3.6 +/- 0.6 cm(3), 2.0 +/- 0.5 cm(3), 9.7 +/- 1.7 cm(3), 2.5 +/- 0.6 cm(3), 2.6 +/- 0.9 cm(3), respectively) than in controls (3.1 +/- 0.7 cm(3), 1.5 +/- 0.2 cm(3), 8.2 +/- 1.3 cm(3), 1.7 +/- 1.4 cm(3), 1.8 +/- 0.4 cm(3), respectively). White matter volume was lower (182.1 +/- 40.5 cm(3)) and CSF volume was higher (300.8 +/- 56.2 cm(3)) in children with PVL than in controls (222.9 +/- 67.2 cm(3), 219.0 +/- 61.8 cm(3), respectively), P < 0.05. No significant difference was found in the total GM volume and the volume of neocortex. CONCLUSION: Preterm children with PVL show regional GM volume increase, possibly explained by axonal sprouting, neuronal hypertrophy and neurogenesis, which in turn may reflect brain plasticity.


Assuntos
Encéfalo/patologia , Líquido Cefalorraquidiano/citologia , Recém-Nascido Prematuro , Leucomalácia Periventricular/patologia , Imageamento por Ressonância Magnética/métodos , Fibras Nervosas Mielinizadas/patologia , Neurônios/patologia , Feminino , Humanos , Recém-Nascido , Masculino
9.
Magn Reson Imaging ; 37: 116-121, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27899333

RESUMO

PURPOSE: Increased Body-Mass-Index (BMI) has been associated with brain atrophy in both gray and white matter structures. However, little is known concerning the integrity of white matter tracts in obesity. The purpose of the study was to evaluate the pattern of changes in white matter microstructure in human adiposity. MATERIAL AND METHODS: The study included 268 participants (52 obese, 96 overweight and 120 normal-weight) that were retrospectively evaluated by Diffusion Tensor Imaging. The fractional anisotropy, axial, radial and mean diffusivity values were compared between the above groups using Tract Based Spatial Statistics. RESULTS: The analysis revealed that the increased BMI was related with decreased fractional anisotropy in several white matter regions including the anterior and posterior thalamic radiation, the inferior fronto-occipital fasciculus, the inferior and superior longitudinal fasciculus, the corpus callosum (callosal body and forceps minor), the uncinate fasciculus, the internal capsule, the corticospinal tract and the cingulum (cingulate gyrus and hippocampus). CONCLUSIONS: Anisotropic diffusion of anatomic regions governing important brain circuits such as reward seeking inhibition, motivation/drive and learning/conditioning decreases with increasing BMI.


Assuntos
Mapeamento Encefálico/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Rede Nervosa/patologia , Obesidade/patologia , Substância Branca/patologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Rede Nervosa/diagnóstico por imagem , Estudos Retrospectivos , Substância Branca/diagnóstico por imagem
10.
J Neuroimaging ; 20(3): 260-6, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19187475

RESUMO

BACKGROUND AND PURPOSE: Multiple system atrophy (MSA) is a progressive neurodegenerative disorder divided into a parkinsonian (MSA-P) and a cerebellar variant. The purpose of this study was to assess regional brain atrophy and iron content using Voxel-based morphometry (VBM) and Voxel-based relaxometry (VBR) respectively, in MSA-P. METHODS: Using biological parametric mapping the effect of brain atrophy was evaluated in T2 relaxation time (T2) measurements by applying analysis of covariance (ANCOVA) and correlation analysis to the VBM and VBR data. Eleven patients with MSA-P (aged 61.9 +/- 11.7 years, disease duration 5.42 +/- 2.5 years) and 11 controls were studied. RESULTS: In comparison to the controls the patients showed decreased gray matter in the putamen, the caudate nuclei, the thalami, the anterior cerebellar lobes, and the cerebral cortex, and white matter atrophy in the pons, midbrain, and peduncles. VBR analysis showed prolonged T2 in various cortical regions. On ANCOVA, when controlling for gray and white matter volume, these regions of prolonged T2 were shrunk. Negative correlation was demonstrated between T2 and gray and white matter volume. CONCLUSIONS: Diffuse brain atrophy, mainly in the motor circuitry is observed in MSA-P. Normalization for atrophy should always be performed in T2 measurements.


Assuntos
Encéfalo/patologia , Processamento de Imagem Assistida por Computador/métodos , Atrofia de Múltiplos Sistemas/patologia , Idoso , Análise de Variância , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fibras Nervosas Mielinizadas/patologia , Fibras Nervosas Amielínicas/patologia
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