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1.
Neuroradiology ; 64(6): 1145-1156, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34719725

RESUMO

INTRODUCTION: In order to augment the certainty of the radiological interpretation of "possible microbleeds" after traumatic brain injury (TBI), we assessed their longitudinal evolution on 3-T SWI in patients with moderate/severe TBI. METHODS: Standardized 3-T SWI and T1-weighted imaging were obtained 3 and 26 weeks after TBI in 31 patients. Their microbleeds were computer-aided detected and classified by a neuroradiologist as no, possible, or definite at baseline and follow-up, separately (single-scan evaluation). Thereafter, the classifications were re-evaluated after comparison between the time-points (post-comparison evaluation). We selected the possible microbleeds at baseline at single-scan evaluation and recorded their post-comparison classification at follow-up. RESULTS: Of the 1038 microbleeds at baseline, 173 were possible microbleeds. Of these, 53.8% corresponded to no microbleed at follow-up. At follow-up, 30.6% were possible and 15.6% were definite. Of the 120 differences between baseline and follow-up, 10% showed evidence of a pathophysiological change over time. Proximity to extra-axial injury and proximity to definite microbleeds were independently predictive of becoming a definite microbleed at follow-up. The reclassification level differed between anatomical locations. CONCLUSIONS: Our findings support disregarding possible microbleeds in the absence of clinical consequences. In selected cases, however, a follow-up SWI-scan could be considered to exclude evolution into a definite microbleed.


Assuntos
Lesões Encefálicas Traumáticas , Imageamento por Ressonância Magnética , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Radiografia
2.
Eur Radiol ; 28(9): 3902-3911, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29572637

RESUMO

OBJECTIVES: To assess observer variability of different reference tissues used for relative CBV (rCBV) measurements in DSC-MRI of glioma patients. METHODS: In this retrospective study, three observers measured rCBV in DSC-MR images of 44 glioma patients on two occasions. rCBV is calculated by the CBV in the tumour hotspot/the CBV of a reference tissue at the contralateral side for normalization. One observer annotated the tumour hotspot that was kept constant for all measurements. All observers annotated eight reference tissues of normal white and grey matter. Observer variability was evaluated using the intraclass correlation coefficient (ICC), coefficient of variation (CV) and Bland-Altman analyses. RESULTS: For intra-observer, the ICC ranged from 0.50-0.97 (fair-excellent) for all reference tissues. The CV ranged from 5.1-22.1 % for all reference tissues and observers. For inter-observer, the ICC for all pairwise observer combinations ranged from 0.44-0.92 (poor-excellent). The CV ranged from 8.1-31.1 %. Centrum semiovale was the only reference tissue that showed excellent intra- and inter-observer agreement (ICC>0.85) and lowest CVs (<12.5 %). Bland-Altman analyses showed that mean differences for centrum semiovale were close to zero. CONCLUSION: Selecting contralateral centrum semiovale as reference tissue for rCBV provides the lowest observer variability. KEY POINTS: • Reference tissue selection for rCBV measurements adds variability to rCBV measurements. • rCBV measurements vary depending on the choice of reference tissue. • Observer variability of reference tissue selection varies between poor and excellent. • Centrum semiovale as reference tissue for rCBV provides the lowest observer variability.


Assuntos
Determinação do Volume Sanguíneo/métodos , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/diagnóstico por imagem , Glioma/irrigação sanguínea , Glioma/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Neoplasias Encefálicas/patologia , Meios de Contraste , Feminino , Glioma/patologia , Substância Cinzenta/irrigação sanguínea , Substância Cinzenta/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valores de Referência , Estudos Retrospectivos , Substância Branca/irrigação sanguínea , Substância Branca/diagnóstico por imagem , Adulto Jovem
3.
Stroke ; 48(12): 3323-3328, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29158448

RESUMO

BACKGROUND AND PURPOSE: Although by definition transient, both transient ischemic attack (TIA) and transient neurological attack (TNA) are associated with cognitive impairment. Determinants and course of cognitive function afterward are, however, unclear. We prospectively determined cognitive performance after TIA and TNA in relation to clinical diagnosis and diffusion-weighted imaging (DWI) results. METHODS: TIA and TNA patients aged ≥45 years without prior stroke or dementia underwent comprehensive cognitive assessment and magnetic resonance imaging within 7 days after the qualifying event. Cognitive tests were repeated after 6 months. Domain-specific compound z scores based on the baseline mean and SD were calculated. Repeated-measures analysis was used to test for differences in domain-specific cognitive performance over time between DWI-positive and DWI-negative patients, as well as between TIA and TNA patients. RESULTS: One hundred twenty-one patients were included (mean age (SD), 64.6 years (9.2 years), 60% TIA and 40% TNA) of whom 32 (26%) had a DWI lesion. Executive function performance decreased over time (mean change in compound score -0.23; P=0.01 adjusted for age, sex, education), whereas attention improved (0.11; P=0.02), and information processing speed and episodic memory remained unchanged. Patients with a DWI lesion had worse executive function at baseline than those without a DWI lesion (compound scores -0.26 versus 0.08; P=0.048), which persisted throughout the study period (P=0.04). Clinical diagnosis (TIA or TNA) was not related to cognitive function over time. CONCLUSIONS: Executive function declines during the first 6 months after TIA or TNA. Patients with an initial DWI lesion have persisting worse executive function than those without.


Assuntos
Função Executiva , Ataque Isquêmico Transitório/psicologia , Doenças do Sistema Nervoso/psicologia , Idoso , Idoso de 80 Anos ou mais , Atenção , Cognição , Estudos de Coortes , Imagem de Difusão por Ressonância Magnética , Progressão da Doença , Feminino , Humanos , Ataque Isquêmico Transitório/diagnóstico por imagem , Masculino , Memória Episódica , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/diagnóstico por imagem , Testes Neuropsicológicos , Tempo de Reação , Acidente Vascular Cerebral/diagnóstico
4.
J Parkinsons Dis ; 7(2): 211-217, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28282809

RESUMO

BACKGROUND: Differentiating Parkinson's disease and atypical parkinsonism on clinical parameters is challenging, especially in early disease courses. This is due to large overlap in symptoms and because the so called red flags, i.e. symptoms indicating atypical parkinsonism, have not (fully) developed. Brain MRI can aid to improve the accuracy and confidence about the diagnosis. OBJECTIVE AND METHODS: In the current paper, we discuss when brain MRI should be performed in the diagnostic work-up of parkinsonism, our preferred brain MRI scanning protocol, and the diagnostic value of specific abnormalities. RESULTS AND CONCLUSIONS: The main purpose of brain MRI is to assess cerebrovascular damage, and to exclude other possible - and sometimes treatable - causes of parkinsonism, such as normal pressure hydrocephalus. Furthermore, brain MRI can support the possible or probable diagnosis of a specific form of atypical parkinsonism.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética , Transtornos Parkinsonianos/diagnóstico por imagem , Transtornos Parkinsonianos/patologia , Diagnóstico Diferencial , Humanos , Sensibilidade e Especificidade
5.
Behav Neurol ; 2017: 5181024, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29348702

RESUMO

INTRODUCTION: Subjective cognitive impairment (SCI), depressive symptoms, and fatigue are common after stroke and are associated with reduced quality of life. We prospectively investigated their prevalence and course after a transient ischemic attack (TIA) or nonfocal transient neurological attack (TNA) and the association with diffusion-weighted imaging (DWI) lesions. METHODS: The Cognitive Failures Questionnaire, Hospital Anxiety and Depression Scale, and Subjective Fatigue subscale from the Checklist Individual Strength were used to assess subjective complaints shortly after TIA or TNA and six months later. With repeated measure analysis, the associations between DWI lesion presence or clinical diagnosis (TIA or TNA) and subjective complaints over time were determined. RESULTS: We included 103 patients (28 DWI positive). At baseline, SCI and fatigue were less severe in DWI positive than in DWI negative patients, whereas at follow-up, there were no differences. SCI (p = 0.02) and fatigue (p = 0.01) increased in severity only in DWI positive patients. There were no differences between TIA and TNA. CONCLUSIONS: Subjective complaints are highly prevalent in TIA and TNA patients. The short-term prognosis is not different between DWI-positive and DWI negative patients, but SCI and fatigue increase in severity within six months after the event when an initial DWI lesion is present.


Assuntos
Disfunção Cognitiva/psicologia , Depressão/psicologia , Fadiga/psicologia , Idoso , Disfunção Cognitiva/complicações , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/fisiopatologia , Depressão/diagnóstico por imagem , Depressão/fisiopatologia , Autoavaliação Diagnóstica , Imagem de Difusão por Ressonância Magnética/métodos , Fadiga/complicações , Fadiga/fisiopatologia , Feminino , Humanos , Ataque Isquêmico Transitório/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Qualidade de Vida , Acidente Vascular Cerebral/complicações , Inquéritos e Questionários
6.
Brain Imaging Behav ; 11(5): 1555-1560, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27744494

RESUMO

Despite long-term successful treatment with cART, impairments in cognitive functioning are still being reported in HIV-infected patients. Since changes in cognitive function may be preceded by subtle changes in brain function, neuroimaging techniques, such as resting-state functional magnetic resonance imaging (rs-fMRI) have become useful tools in assessing HIV-associated abnormalities in the brain. The purpose of the current study was to examine the extent to which HIV infection in virologically suppressed patients is associated with disruptions in subcortical regions of the brain in comparison to a matched HIV-negative control group. The sample consisted of 72 patients and 39 controls included between January 2012 and January 2014. Resting state functional connectivity was determined between fourteen regions-of-interest (ROI): the left and right nucleus accumbens, amygdala, caudate nucleus, hippocampus, putamen, pallidum and thalamus. A Bayesian method was used to estimate resting-state functional connectivity, quantified in terms of partial correlations. Both groups showed the strongest partial correlations between the left and right caudate nucleus and the left and right thalamus. However, no differences between the HIV patients and controls were found between the posterior expected network densities (control network density = 0.26, SD = 0.05, patient network density = 0.26, SD = 0.04, p = 0.58). The results of the current study show that HIV does not affect subcortical connectivity in virologically controlled patients who are otherwise healthy.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/fisiopatologia , Adulto , Idoso , Algoritmos , Teorema de Bayes , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Quimioterapia Combinada , Feminino , Infecções por HIV/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Estudos Prospectivos , Descanso
7.
Mitochondrion ; 32: 36-41, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27865797

RESUMO

We developed the first user-friendly, semi-quantitative, and quick-to-perform Radboud Centre for Mitochondrial Medicine Pediatric MRI score (RCMM-PMRIS), focusing on the six most commonly described neuroimaging abnormalities in the literature. The RCMM-PMRIS was validated through individual review of 30 sets of brain MRI studies in 24 patients with genetically confirmed mitochondrial disorders by six raters. The application of RCMM-PMRIS can help to define the extent of the brain involvement and therefore to assess the radiological mitochondrial disease severity, to monitor disease progression and consequently to act as an outcome measure for treatment effects in patients with mitochondrial disease.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Doenças Mitocondriais/diagnóstico por imagem , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Índice de Gravidade de Doença
8.
Pol J Radiol ; 81: 363-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27559425

RESUMO

BACKGROUND: Previous case-control studies have suggested that the absence of a swallow-tail appearance in the substantia nigra on high-resolution SWI, representing nigrosome-1, has high accuracy to identify Parkinson's disease (PD). The first goal of our study was to evaluate nigrosome-1 ex vivo using optimized high-resolution susceptibility sensitive MRI. Our second goal was to evaluate its diagnostic value in vivo using a clinical 3T SWI sequence to differentiate between PD and atypical parkinsonism (AP) in a cohort of patients with early-stage parkinsonism. MATERIAL/METHODS: Case-control pilot study to evaluate nigrosome-1 ex vivo (2 PD, 2 controls), using high-resolution susceptibility sensitive sequences at 11.7 T MRI. Next, evaluation of nigrosome-1 in vivo using a clinical 3 T SWI sequence in a prospective cohort of 60 patients with early-stage parkinsonism (39 PD, 21 AP). Moreover, 12 control subjects were scanned. The bilateral substantia nigra was evaluated by two neuroradiologists for the presence, absence or indecisive presence of nigrosome-1. The discriminative power was evaluated by Receiver-Operating Characteristic. RESULTS: We identified nigrosome-1 in ex vivo control subjects. Nigrosome-1 was not identified in the ex vivo PD cases. In our prospective clinical cohort study, the AUC for the swallow-tail sign to discriminate between PD and AP was 0.56 (0.41-0.71) for reader 1 and 0.68 (0.55-0.82) for reader 2. CONCLUSIONS: The diagnostic accuracy of the swallow-tail sign was marginal to discriminate between PD and AP using our clinical 3 T SWI sequence.

9.
AIDS ; 29(16): 2139-48, 2015 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-26544578

RESUMO

OBJECTIVE: The objective of the current study is to integrate results from extensive neuropsychological assessment, subjective wellbeing reports and structural neuroimaging findings in successfully treated HIV-infected patients in comparison with a HIV-negative control group. DESIGN: A cross-sectional study. METHODS: Neuropsychological functioning and self-reported wellbeing were assessed in a group of 102 virologically suppressed HIV-infected patients on combination antiretroviral therapy (cART) and 56 controls. Both groups underwent magnetic resonance (MR) examinations and grey matter, white matter and subcortical volumes were determined. Brain parenchymal fraction (BPF) was calculated as an estimated measure of global brain atrophy. RESULTS: HIV-infected patients showed worse information processing speed (P = 0.01) and motor function (P = 0.03) than controls. Also, higher levels of anxiety and depressive symptoms, somatic and cognitive complaints, sleep problems and health distress were found, as well as lower levels of general health perceptions, social functioning and energy (P < 0.05). No differences in wellbeing reports were found between patients on regimens containing either efavirenz or nevirapine and patients on cART without these drugs (P > 0.05). Patients had a smaller BPF (P = 0.04) and thalamus (P = 0.05) than controls. A lower BPF was related to worse motor function and information processing speed in the patients. A smaller thalamus volume was related to lower motor function in the patient group and lower speed of information processing in the controls. CONCLUSION: No profound deficits were found in the current study. The present results demonstrate that HIV has a minor impact on brain, cognition and wellbeing among HIV-infected patients who are otherwise healthy and maintained on a good control of cART.


Assuntos
Antirretrovirais/uso terapêutico , Terapia Antirretroviral de Alta Atividade , Encéfalo/fisiologia , Cognição , Infecções por HIV/tratamento farmacológico , Infecções por HIV/psicologia , Qualidade de Vida/psicologia , Adolescente , Adulto , Idoso , Encéfalo/patologia , Estudos Transversais , Feminino , Infecções por HIV/virologia , HIV-1/isolamento & purificação , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
10.
Ann Neurol ; 78(6): 1005-10, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26447866

RESUMO

Transient ischemic attack (TIA) can be difficult to diagnose. Episodes of acute atypical or nonfocal neurological symptoms, referred to as transient neurological attack (TNA), are as prevalent as TIAs. Diffusion-weighted imaging (DWI) provides evidence of acute cerebral ischemia in a third of TIA patients. We now report that DWI shows acute ischemia in 23% of patients clinically diagnosed as TNA by experienced stroke neurologists. This questions the accuracy of clinically diagnosing TIA and suggests added value for early magnetic resonance imaging after an episode of acute onset atypical or nonfocal neurological symptoms.


Assuntos
Imagem de Difusão por Ressonância Magnética/normas , Ataque Isquêmico Transitório/diagnóstico , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
11.
Neuroradiology ; 57(7): 655-69, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25845807

RESUMO

INTRODUCTION: The aim of this study is to evaluate whether the diagnostic accuracy of 3 T brain MRI is improved by region of interest (ROI) measures of diffusion tensor imaging (DTI), to differentiate between neurodegenerative atypical parkinsonism (AP) and Parkinson's disease (PD) in early stage parkinsonism. METHODS: We performed a prospective observational cohort study of 60 patients presenting with early stage parkinsonism and initial uncertain diagnosis. At baseline, patients underwent a 3 T brain MRI including DTI. After clinical follow-up (mean 28.3 months), diagnoses could be made in 49 patients (30 PD and 19 AP). Conventional brain MRI was evaluated for regions of atrophy and signal intensity changes. Tract-based spatial statistics and ROI analyses of DTI were performed to analyze group differences in mean diffusivity (MD) and fractional anisotropy (FA), and diagnostic thresholds were determined. Diagnostic accuracy of conventional brain MRI and DTI was assessed with the receiver operating characteristic (ROC). RESULTS: Significantly higher MD of the centrum semiovale, body corpus callosum, putamen, external capsule, midbrain, superior cerebellum, and superior cerebellar peduncles was found in AP. Significantly increased MD of the putamen was found in multiple system atrophy-parkinsonian form (MSA-P) and increased MD in the midbrain and superior cerebellar peduncles in progressive supranuclear palsy (PSP). The diagnostic accuracy of brain MRI to identify AP as a group was not improved by ROI measures of MD, though the diagnostic accuracy to identify MSA-P was slightly increased (AUC 0.82 to 0.85). CONCLUSION: The diagnostic accuracy of brain MRI to identify AP as a group was not improved by the current analysis approach to DTI, though DTI measures could be of added value to identify AP subgroups.


Assuntos
Imagem de Tensor de Difusão , Imageamento por Ressonância Magnética , Imagem Multimodal , Transtornos Parkinsonianos/diagnóstico , Idoso , Anisotropia , Encéfalo/patologia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Curva ROC
12.
BMC Neurol ; 15: 36, 2015 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-25880287

RESUMO

BACKGROUND: Transient ischemic attacks (TIA) are characterized by acute onset focal neurological symptoms and complete recovery within 24 hours. Attacks of nonfocal symptoms not fulfilling the criteria for TIA but lacking a clear alternative diagnosis are called transient neurological attacks (TNA). Although TIA symptoms are transient in nature, cognitive complaints may persist. In particular, attacks consisting of both focal and nonfocal symptoms (mixed TNA) have been found to be associated with an increased risk of dementia. We aim to study the prevalence, etiology and risk factors of cognitive impairment after TIA or TNA. METHODS/DESIGN: CONNECT is a prospective cohort study on cognitive function after TIA and TNA. In total, 150 patients aged ≥45 years with a recent (<7 days after onset) TIA or TNA and no history of stroke or dementia will be included. We will classify events as: TIA, nonfocal TNA, or mixed TNA. Known short lasting paroxysmal neurological disorders like migraine aura, seizures and Ménière disease are excluded from the diagnosis of TNA. Patients will complete a comprehensive neuropsychological assessment and undergo MRI <7 days after the qualifying event and again after six months. The primary clinical outcomes will be cognitive function at baseline and six months after the primary event. Imaging outcomes include the prevalence and evolution of DWI lesions, white matter hyperintensities and lacunes, as well as resting state networks functionality and white matter microstructural integrity. Differences between types of event and DWI, as well as determinants of both clinical and imaging outcomes, will be assessed. DISCUSSION: CONNECT can provide insight in the prevalence, etiology and risk factors of cognitive impairment after TIA and TNA and thereby potentially identify a new group of patients at increased risk of cognitive impairment.


Assuntos
Transtornos Cognitivos/epidemiologia , Ataque Isquêmico Transitório/epidemiologia , Idoso , Transtornos Cognitivos/patologia , Transtornos Cognitivos/psicologia , Estudos de Coortes , Feminino , Humanos , Ataque Isquêmico Transitório/patologia , Ataque Isquêmico Transitório/psicologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Testes Neuropsicológicos , Prevalência , Estudos Prospectivos , Fatores de Risco
13.
Front Biosci (Elite Ed) ; 6(2): 360-9, 2014 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-24896211

RESUMO

In this review article, conventional brain MRI and advanced MRI techniques in Parkinson`s disease (PD) are discussed, with emphasis on clinical relevance. Conventional brain MRI sequences generally demonstrate limited abnormalities specific for PD and in clinical practice brain MRI is mainly used to exclude other pathology. Possibly, brain MRI at higher magnetic field strengths could provide new diagnostic markers. In recent years, new imaging techniques such as susceptibility weighted imaging (SWI), diffusion (tensor) MRI, magnetization transfer imaging (MTI), and functional MRI (f-MRI) have been applied to patient cohorts with PD to improve understanding of pathophysiologic changes, including functional connectivity. These advanced MRI techniques hold promise to provide additional diagnostic markers for early stage PD, as demonstrated by diffusional changes in the orbital-frontal region in the pre-motor phase of PD. Whether these advanced MRI techniques provide new diagnostic markers for early stage PD, remains a debate. Standardization of scanning protocols and post-processing methods, and validation of diagnostic criteria is crucial for these advanced MRI techniques. For this, well designed prospective clinical cohort studies are needed.


Assuntos
Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Doença de Parkinson/diagnóstico , Doença de Parkinson/patologia , Humanos , Imageamento por Ressonância Magnética/tendências
14.
J Neurol Sci ; 332(1-2): 21-9, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23866820

RESUMO

Differentiating Parkinson's disease (PD) from other types of neurodegenerative atypical parkinsonism (AP) can be challenging, especially in early disease stages. Routine brain magnetic resonance imaging (MRI) can show atrophy or signal changes in several parts of the brain with fairly high specificity for particular forms of AP, but the overall diagnostic value of routine brain MRI is limited. In recent years, various advanced MRI sequences have become available, including diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI). Here, we review available literature on the value of diffusion MRI for identifying and quantifying different patterns of neurodegeneration in PD and AP, in relation to what is known of underlying histopathologic changes and clinical presentation of these diseases. Next, we evaluate the value of diffusion MRI to differentiate between PD and AP and the potential value of serial diffusion MRI to monitor disease progression. We conclude that diffusion MRI may quantify patterns of neurodegeneration which could be of additional value in clinical use. Future prospective clinical cohort studies are warranted to assess the added diagnostic value of diffusion MRI.


Assuntos
Imagem de Difusão por Ressonância Magnética , Doença de Parkinson/diagnóstico , Transtornos Parkinsonianos/diagnóstico , Encéfalo/patologia , Humanos
16.
Brain Inj ; 26(12): 1439-50, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22731791

RESUMO

OBJECTIVE: This study compares inter-rater-reliability, lesion detection and clinical relevance of T2-weighted imaging (T2WI), Fluid Attenuated Inversion Recovery (FLAIR), T2*-gradient recalled echo (T2*-GRE) and Susceptibility Weighted Imaging (SWI) in Traumatic Brain Injury (TBI). METHODS: Three raters retrospectively scored 56 TBI patients' MR images (12-76 years old, median TBI-MRI interval 7 weeks) on number, volume, location and intensity. Punctate lesions (diameter <10 mm) were scored separately from large lesions (diameter ≥ 10 mm). Injury severity was assessed with the Glasgow Coma Scale (GCS), outcome with the Glasgow Outcome Scale-Extended (GOSE). RESULTS: Inter-rater-reliability for lesion volume and punctate lesion count was good (ICC = 0.69-0.94) except for punctate lesion count on T2WI (ICC = 0.19) and FLAIR (ICC = 0.15). SWI showed the highest number of lesions (mean = 30.0), followed by T2*-GRE (mean = 15.4), FLAIR (mean = 3.1) and T2WI (mean = 2.2). Sequences did not differ in detected lesion volume. Punctate lesion count on T2*-GRE (r = -0.53) and SWI (r = -0.49) correlated with the GCS (p < 0.001). CONCLUSIONS: T2*-GRE and SWI are more sensitive than T2WI and FLAIR in detecting (haemorrhagic) traumatic punctate lesions. The correlation between number of punctate lesions on T2*-GRE/SWI and the GCS indicates that haemorrhagic lesions are clinically relevant. The considerable inter-rater-disagreement in this study advocates cautiousness in interpretation of punctate lesions using T2WI and FLAIR.


Assuntos
Lesões Encefálicas/diagnóstico , Encéfalo/patologia , Imageamento por Ressonância Magnética , Adolescente , Adulto , Idoso , Lesões Encefálicas/patologia , Criança , Feminino , Escala de Resultado de Glasgow , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Índices de Gravidade do Trauma
17.
J Neurol ; 259(5): 929-35, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22008875

RESUMO

Various signs on routine brain MRI can help differentiate between Parkinson's disease (PD) and the various forms of atypical parkinsonism (AP). Here, we evaluate what routine brain MRI contributes to the clinical diagnosis, in both early and advanced disease stages. We performed a prospective observational study in 113 patients with parkinsonism, but without definite diagnosis upon inclusion. At baseline, patients received a structured interview, comprehensive and standardized neurological assessment, and brain MRI. The silver standard diagnosis was made after 3 years of follow-up (PD n = 43, AP n = 57), which was based on disease progression, repeat standardized neurological examination and response to treatment. The clinical diagnosis was classified as having either 'low certainty' (lower than 80%) or 'high certainty' (80% or higher). The added diagnostic yield of baseline MRI results were then studied relative to clinical neurological evaluation at presentation, and at follow-up. Sensitivity and specificity for separating AP from PD were calculated for all potentially distinguishing MRI abnormalities described previously in the literature. MRI abnormalities showed moderate to high specificity but limited sensitivity for the diagnosis of AP. These MRI abnormalities contributed little over and above the clinically based diagnosis, except when the clinical diagnosis was uncertain. For these patients, presence of putaminal or cerebellar atrophy was particularly indicative of AP. Routine brain MRI has limited added value for differentiating between PD and AP when clinical certainty is already high, but has some diagnostic value when the clinical diagnosis is still uncertain.


Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Transtornos Parkinsonianos/diagnóstico , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/diagnóstico , Exame Neurológico , Curva ROC , Sensibilidade e Especificidade , Paralisia Supranuclear Progressiva/diagnóstico
18.
Biol Psychiatry ; 65(9): 812-8, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19028381

RESUMO

BACKGROUND: The amygdala and hippocampus play a key role in the neural circuitry mediating depression. It remains unclear how much structural and functional changes of amygdala and hippocampus reflect the acute state of depression or an underlying neurobiological trait marker of depression. METHODS: High-resolution anatomical images were acquired in 20 medication-naïve major depressive disorder (MDD) patients with a current first episode, 20 medication-free patients recovered from a first episode of MDD, and 20 healthy control subjects that were matched for age, gender, and level of education. Manual volumetry of amygdala and hippocampus was performed on coronal images. Volumetric measurements of brain volume and intracranial volume were acquired with automatic segmentation procedures. RESULTS: Both amygdalae were significantly enlarged in currently depressed patients, whereas there was no significant difference between recovered patients and control subjects. The amygdala enlargement correlated positively with the severity of depressive state but with no other clinical or neuropsychological variable. The hippocampal volume did not differ between groups. CONCLUSIONS: A state related increase of amygdala volume can be detected early in the course of MDD. Neurotoxic effects might account for the fact that state-related amygdala enlargement has not been found in recurrent depression with relative long illness duration.


Assuntos
Tonsila do Cerebelo/patologia , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/patologia , Hipocampo/patologia , Adolescente , Adulto , Encéfalo/patologia , Estudos de Casos e Controles , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Índice de Gravidade de Doença
19.
Med Sci Monit ; 12(4): MT17-21, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16572061

RESUMO

BACKGROUND: It has recently been suggested that new imaging methods such as magnetization transfer imaging (MTI) may play an important role in detecting subtle gray- and white-matter abnormalities in schizophrenia. The aim of the study was to investigate whether MTI, analyzed on a voxel-by-voxel basis, could identify areas of abnormal magnetization transfer ratio (MTR) in patients with schizophrenia. MATERIAL/METHODS: Twenty schizophrenic patients and 23 healthy controls matched for handedness and demographic variables underwent MTI and T1-weighted structural MRI in a 3-tesla scanner. Post-processing was performed with SPM99 and included co-registration of the MT-weighted and non-MT-weighted images, calculation of the MTR maps, spatial normalization, and smoothing. Differences in the MTR maps between groups were assessed using two-sample t-tests. Significant changes in MTR were detected at an individual voxel threshold of p < 0.05. RESULTS: Group comparisons revealed no significant MTR changes, although there was a trend towards MTR reduction in the left superior temporal gyrus, in the right occipital cortex, and left periventricular white matter in patients compared with controls prior to correction for multiple comparisons (p < 0.001, uncorrected). CONCLUSIONS: MTI and voxel-by-voxel statistical analysis used in the study failed to identify regions of significant MTR reductions in schizophrenic patients. Our results disagree with findings of widespread MTR abnormalities reported in recent literature.


Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Esquizofrenia/patologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade
20.
Psychiatr Pol ; 39(4): 761-71, 2005.
Artigo em Polonês | MEDLINE | ID: mdl-16237980

RESUMO

The causes of metabolic brain changes in patients with anorexia nervosa are still not fully explained. The purpose of this study was to use the 1H-MRS method in investigating metabolic changes in the brain of patients with anorexia nervosa. We studied 10 patients for visible alternations in brain metabolism and compared the results to healthy controls. 1H-MRS was acquired by the method of single voxels in white and grey matter. Proton MRS was performed after image guided localization using stimulated echo acquisition mode (STEAM) sequence with a short echo time of 20 ms. For data evaluation we used standard Siemens software and the additional PC. Choosing of the MRS sequences was related with particular interest in metabolites of short time echo: myoinositol and lipids. Besides this we evaluated peaks of: N-acetylaspartate (NAN), creatine (Cr) and choline (Cho). The results show significant differences in the levels of metabolites connected with fatty metabolism. In white matter we observed the reduction of lip-peak. The data was evaluated approximately and presented as lip:Cr. We did not observe any differences in other metabolites. As far as we know similar results had been reported and our study confirmed significant disorders in metabolism of these chemicals in patients with anorexia nervosa.


Assuntos
Anorexia Nervosa/metabolismo , Encéfalo/metabolismo , Espectroscopia de Ressonância Magnética , Adolescente , Adulto , Anorexia Nervosa/diagnóstico , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Estudos de Casos e Controles , Colina/metabolismo , Feminino , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Humanos , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Neurotransmissores/metabolismo , Prótons
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