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1.
Neuroimage Clin ; 14: 316-322, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28224079

RESUMO

Pediatric HIV patients often suffer with neurodevelopmental delay and subsequently cognitive impairment. While tissue injury in cortical and subcortical regions in the brain of adult HIV patients has been well reported there is sparse knowledge about these changes in perinatally HIV infected pediatric patients. We analyzed cortical thickness, subcortical volume, structural connectivity, and neurocognitive functions in pediatric HIV patients and compared with those of pediatric healthy controls. With informed consent, 34 perinatally infected pediatric HIV patients and 32 age and gender matched pediatric healthy controls underwent neurocognitive assessment and brain magnetic resonance imaging (MRI) on a 3 T clinical scanner. Altered cortical thickness, subcortical volumes, and abnormal neuropsychological test scores were observed in pediatric HIV patients. The structural network connectivity analysis depicted lower connection strengths, lower clustering coefficients, and higher path length in pediatric HIV patients than healthy controls. The network betweenness and network hubs in cortico-limbic regions were distorted in pediatric HIV patients. The findings suggest that altered cortical and subcortical structures and regional brain connectivity in pediatric HIV patients may contribute to deficits in their neurocognitive functions. Further, longitudinal studies are required for better understanding of the effect of HIV pathogenesis on brain structural changes throughout the brain development process under standard ART treatment.


Assuntos
Mapeamento Encefálico , Encéfalo/diagnóstico por imagem , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/etiologia , Infecções por HIV/complicações , Adolescente , Antígenos CD4/metabolismo , Criança , Feminino , Infecções por HIV/metabolismo , Humanos , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Masculino , Rede Nervosa/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Testes Neuropsicológicos
2.
J Neurol ; 263(11): 2308-2318, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27544505

RESUMO

Parkinson's disease (PD) is a progressive neurological disorder and appears to have gender-specific symptoms. Studies have observed a higher frequency for development of PD in male than in female. In the current study, we evaluated the gender-based changes in cortical thickness and structural connectivity in PD patients. With informed consent, 64 PD (43 males and 21 females) patients, and 46 (12 males and 34 females) age-matched controls underwent clinical assessment including Mini-Mental State Examination (MMSE) and magnetic resonance imaging on a 1.5 Tesla clinical MR scanner. Whole brain high-resolution T1-weighted images were acquired from all subjects and used to measure cortical thickness and structural network connectivity. No significant difference in MMSE score was observed between male and female both in control and PD subjects. Male PD patients showed significantly reduced cortical thickness in multiple brain regions including frontal, parietal, temporal, and occipital lobes as compared with those in female PD patients. The graph theory-based network analysis depicted lower connection strengths, lower clustering coefficients, and altered network hubs in PD male than in PD female. Male-specific cortical thickness changes and altered connectivity in PD patients may derive from behavioral, physiological, environmental, and genetical differences between male and female, and may have significant implications in diagnosing and treating PD among genders.


Assuntos
Córtex Cerebral/patologia , Vias Neurais/patologia , Doença de Parkinson/patologia , Caracteres Sexuais , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Estudos de Casos e Controles , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Entrevista Psiquiátrica Padronizada , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem
4.
Neuroimage Clin ; 7: 598-604, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25844314

RESUMO

In the current study, we have evaluated the performance of magnetic resonance (MR) T1rho (T1ρ) imaging and CSF biomarkers (T-tau, P-tau and Aß-42) in characterization of Alzheimer's disease (AD) patients from mild cognitive impairment (MCI) and control subjects. With informed consent, AD (n = 27), MCI (n = 17) and control (n = 17) subjects underwent a standardized clinical assessment and brain MRI on a 1.5-T clinical-scanner. T1ρ images were obtained at four different spin-lock pulse duration (10, 20, 30 and 40 ms). T1ρ maps were generated by pixel-wise fitting of signal intensity as a function of the spin-lock pulse duration. T1ρ values from gray matter (GM) and white matter (WM) of medial temporal lobe were calculated. The binary logistic regression using T1ρ and CSF biomarkers as variables was performed to classify each group. T1ρ was able to predict 77.3% controls and 40.0% MCI while CSF biomarkers predicted 81.8% controls and 46.7% MCI. T1ρ and CSF biomarkers in combination predicted 86.4% controls and 66.7% MCI. When comparing controls with AD, T1ρ predicted 68.2% controls and 73.9% AD, while CSF biomarkers predicted 77.3% controls and 78.3% for AD. Combination of T1ρ and CSF biomarkers improved the prediction rate to 81.8% for controls and 82.6% for AD. Similarly, on comparing MCI with AD, T1ρ predicted 35.3% MCI and 81.9% AD, whereas CSF biomarkers predicted 53.3% MCI and 83.0% AD. Collectively CSF biomarkers and T1ρ were able to predict 59.3% MCI and 84.6% AD. On receiver operating characteristic analysis T1ρ showed higher sensitivity while CSF biomarkers showed greater specificity in delineating MCI and AD from controls. No significant correlation between T1ρ and CSF biomarkers, between T1ρ and age, and between CSF biomarkers and age was observed. The combined use of T1ρ and CSF biomarkers have promise to improve the early and specific diagnosis of AD. Furthermore, disease progression form MCI to AD might be easily tracked using these two parameters in combination.


Assuntos
Doença de Alzheimer/diagnóstico , Biomarcadores/líquido cefalorraquidiano , Disfunção Cognitiva/diagnóstico , Imageamento por Ressonância Magnética/métodos , Idoso , Doença de Alzheimer/líquido cefalorraquidiano , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Área Sob a Curva , Disfunção Cognitiva/líquido cefalorraquidiano , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Testes Neuropsicológicos , Curva ROC , Sensibilidade e Especificidade , Proteínas tau/líquido cefalorraquidiano
5.
J Radiol Case Rep ; 6(6): 10-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23378877

RESUMO

Tumoral calcinosis is uncommon in toddlers, and rare within the subscapular area. Although typically benign, tumoral calcinosis is often incorrectly diagnosed prior to biopsy. We present a case of subscapular tumoral calcinosis in a 16-month old girl and discuss the radiological findings on X-ray, ultrasound, computed tomography and magnetic resonance imaging, including the first description of T1-weighted post contrast imaging, which demonstrate the fibrotic components of tumoral calcinosis.


Assuntos
Neoplasias Ósseas/diagnóstico , Neoplasias Ósseas/cirurgia , Calcinose/diagnóstico , Calcinose/cirurgia , Diagnóstico por Imagem/métodos , Escápula/diagnóstico por imagem , Escápula/patologia , Feminino , Humanos , Lactente , Radiografia , Resultado do Tratamento
6.
Pediatr Rheumatol Online J ; 7: 2, 2009 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-19138427

RESUMO

BACKGROUND: Chronic recurrent multifocal osteomyelitis (CRMO) is an inflammatory, non-infectious osteopathy that affects predominantly patients

7.
Pediatr Radiol ; 36(10): 1105-7, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16819598

RESUMO

Liver involvement in Langerhans cell histiocytosis (LCH) typically presents with hepatomegaly and other signs of liver dysfunction. We present an 11-month-old child having only minimally elevated liver enzymes as an indication of liver involvement. Using sonography as the initial diagnostic tool followed by MRI, LCH of the liver was revealed. A review of sonographic, CT, MRI and MR cholangiopancreatography findings in liver LCH is presented. We recommend that physicians consider sonography and MRI screening for liver involvement in patients with newly diagnosed LCH, as periportal involvement may be present with little or no liver function abnormality present, as in this patient.


Assuntos
Diagnóstico por Imagem , Histiocitose de Células de Langerhans/diagnóstico , Hepatopatias/diagnóstico , Diagnóstico Diferencial , Histiocitose de Células de Langerhans/tratamento farmacológico , Humanos , Lactente , Hepatopatias/tratamento farmacológico , Testes de Função Hepática , Masculino
8.
J Magn Reson Imaging ; 22(6): 810-2, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16270291

RESUMO

PURPOSE: To examine the potential utility of applying heat to increase the uptake of intravenous gadolinium (Gd) contrast into the knee joint in order to optimize MR arthrography. MATERIALS AND METHODS: At 1.5T, 16 knees in eight patients without prior surgery, injury, or pain were examined before and 30 minutes after intravenous administration of Gd contrast (0.1 mM/kg). Between scans a heating pad was applied to the anterior aspect of eight randomly selected knees (the contralateral knee served as the control). Initial and postcontrast imaging consisted of identical axial T1-weighted sequences (TR/TE = 500/14 msec) without fat suppression. On the initial and postcontrast images, regions of interest (ROIs) were placed at identical locations in the suprapatellar pouch and the intercondylar notch by a reader blinded to the treated side. The values at these two locations were averaged and the change in joint signal intensity was calculated. The differences between the heated and unheated knees were also calculated. RESULTS: Seven of the eight knees treated with heat had increased joint enhancement compared to the contralateral control, with percentage changes in joint signal intensity (heated knee vs. control) of +38%, +80%, +121%, +145%, +150%, +164%, and +177%. Overall there was a doubling of signal intensity (125%) on the heated side compared to the contralateral control (with significance at P = 0.039). One patient was excluded because of a prior knee injury. CONCLUSION: The application of external heat increases uptake of intravenously administered Gd contrast into the knee joint, and may help to optimize indirect MR arthrography at a relatively low cost.


Assuntos
Temperatura Alta , Articulação do Joelho/anatomia & histologia , Imageamento por Ressonância Magnética/métodos , Adulto , Meios de Contraste/administração & dosagem , Feminino , Gadolínio/administração & dosagem , Humanos , Masculino
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