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1.
Med Klin Intensivmed Notfmed ; 113(6): 456-463, 2018 09.
Artigo em Alemão | MEDLINE | ID: mdl-30105559

RESUMO

The reciprocal culprit-victim relationship between the brain and the heart leads to dysfunction and damage to the other organ, especially in acute and severe diseases of one of both organs. In addition, both organ systems can be affected by identical systemic processes, e. g., arteriosclerotic changes. Cardiac embolic formation and pumping failure lead to focal cerebral ischemia or global hypoxia. Cerebral diseases leading to cardiac changes are acute cerebrovascular attacks such as cerebral infarction, intracerebral hemorrhage and subarachnoid hemorrhage, as well as epileptic seizures. The pathophysiological mechanisms of changes of the brain-heart axis include cerebrally induced autonomic dysregulation, neuroendocrine regulatory disorders, and systemic inflammatory processes. The effects on the heart are evident in up to 75% of patients with acute brain diseases leading to ECG changes, arrhythmias, increase in cardiac enzymes and myocardial damage even to sudden cardiac death. For this reason, cardiac monitoring should be provided in severe acute brain diseases.


Assuntos
Isquemia Encefálica , Encéfalo , Coração , Doença Aguda , Encéfalo/fisiopatologia , Hemorragia Cerebral , Coração/fisiopatologia , Humanos
2.
Eur J Neurol ; 25(2): 247-e9, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29024243

RESUMO

BACKGROUND AND PURPOSE: New diagnostic criteria of multiple sclerosis (MS) increase the number of patients being diagnosed with MS whilst a substantial part might not convert to clinically definite MS (CDMS). The diagnostic accuracy of the McDonald 2005 and 2010 criteria for conversion to CDMS was evaluated in an unselected cohort of patients in whom an MS diagnostic work-up was decided. METHODS: Clinical, magnetic resonance imaging and cerebrospinal fluid data were analysed for all patients who presented with symptoms suspicious for MS at the university based MS outpatient clinic between 2006 and 2010 (n = 165). RESULTS: Follow-up was available for 131 patients. During the mean follow-up period of 2 years, 19% of patients developed CDMS whereas 64% of the patients fulfilling McDonald 2010 criteria did not convert to CDMS. CONCLUSION: The low clinical conversion rate indicates that the new diagnostic criteria may increase the incidence of MS cases with a less active disease course.


Assuntos
Progressão da Doença , Esclerose Múltipla/diagnóstico , Sintomas Prodrômicos , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/fisiopatologia , Adulto Jovem
3.
AJNR Am J Neuroradiol ; 38(2): 264-269, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28059711

RESUMO

BACKGROUND AND PURPOSE: Quantitative MR imaging parameters help to evaluate disease progression in multiple sclerosis and increase correlation with clinical disability. We therefore hypothesized that T1 values might be a marker for ongoing tissue damage or even remyelination and may help increase clinical correlation. MATERIALS AND METHODS: MR imaging was performed in 17 patients with relapsing-remitting MS at baseline and after 12 months of starting immunotherapy with dimethyl fumarate. On baseline images, lesion segmentation was performed for normal-appearing white matter, T2 hyperintense (FLAIR lesions), T1 hypointense (black holes), and contrast-enhancing lesions, and T1 relaxation times were obtained at baseline and after 12 months. Changes in clinical status were assessed by using the Expanded Disability Status Scale and Symbol Digit Modalities Test at both dates (Expanded Disability Status Scale-difference/Symbol Digit Modalities Test-diff). RESULTS: The highest T1 relaxation time at baseline was measured in black holes (1460.2 ± 209.46 ms) followed by FLAIR lesions (1400.38 ± 189.1 ms), pure FLAIR lesions (1327.5 ± 210.04 ms), contrast-enhancing lesions (1205.59 ± 199.95 ms), and normal-appearing white matter (851.34 ± 30.61 ms). After 12 months, T1 values had decreased significantly in black holes (1369.4 ± 267.81 ms), contrast-enhancing lesions (1079.57 ± 183.36 ms) (both P < .001), and normal-appearing white matter (841.98 ± 36.1 ms, P = .006). With the Jonckheere-Terpstra Test, better clinical scores were associated with decreasing T1 relaxation times in black holes (P < .05). CONCLUSIONS: T1 relaxation time is a useful quantitative MR imaging technique, which helps detect changes in MS lesions with time. We assume that these changes are associated with the degree of myelination within the lesions themselves and are pronounced in black holes. Additionally, decreasing T1 values in black holes were associated with clinical improvement.


Assuntos
Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/patologia , Recidiva , Substância Branca/patologia
4.
AJNR Am J Neuroradiol ; 37(5): 963-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26744444

RESUMO

BACKGROUND AND PURPOSE: Identification of lesions in specific locations gains importance in multiple sclerosis imaging diagnostic criteria. In clinical routine, axial scans are usually exclusively obtained to depict the cervical spinal cord or used to confirm suspected lesions on sagittal scans. We sought to evaluate the detection rate for MS lesions on axial T2WI scans with full spinal cord coverage in comparison with sagittal scans. MATERIALS AND METHODS: One hundred fifteen patients with definite or suspected MS underwent an MR imaging examination including 3-mm sagittal and 3.5-mm axial T2-weighted images with full spinal cord coverage. T2WI lesions were identified on axial and sagittal scans independently by 2 raters. Axial diameter, craniocaudal extension, lesion intensity, and location were analyzed. RESULTS: Four hundred forty-nine of 509 (88.2%) lesions were detected on axial and 337/509 (66.2%) on sagittal scans. Only 277/449 (61.7%) axial lesions were also detected on sagittal images. The number of lesions visible on sagittal and axial images was dependent on the axial lesion diameter (P < .001). CONCLUSIONS: Axial T2WI scans with full spinal cord coverage showed 22% more lesions in patients with MS in comparison with sagittal scans, especially for lesions with small axial diameters. We suggest including biplanar spinal MR imaging with full spinal cord coverage for lesion detection in MS in clinical routine and for clinical studies.


Assuntos
Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
5.
Clin Neuroradiol ; 26(4): 457-464, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25895017

RESUMO

PURPOSE: Phase imaging provides additional information on multiple sclerosis (MS) lesions and may in combination with mean diffusivity (MD) and magnetization transfer ratio (MTR) help differentiating heterogeneity of MS lesion pathology. METHODS: Magnetic resonance imaging (MRI) was performed in 23 MS patients including diffusion tensor imaging (DTI), magnetization transfer imaging (MTI), and SWI. Mean values (MTR, MD, and homodyne filtered phase) from 138 chronic MS lesions and normal appearing white matter (NAWM) were obtained and correlations examined. For explorative analysis, a divisive hierarchical clustering algorithm was applied. RESULTS: Phase characteristics were an independent characteristic of chronic T2 lesions, as MTR and MD were not correlated with phase values (R = - 0.23, R = - 0.18). Dependent on MTR, MD, and phase, cluster analysis led to five lesion groups. Of the two groups with phase values close to NAWM, one presented with highest MD and most severe MTR decrease (p = 0.01), the other with slight MD increase and MTR decrease. Two lesion groups with highest phase values (p = 0.01) displayed slightly increased MD and moderate decrease in MTR. Clinical data including EDSS, disease duration, and age did not differ significantly between groups. CONCLUSIONS: Increased phase is predominantly detectable in lesions with clear MTR decrease but only moderate MD increase. Phase images seem to represent an independent parameter for MS lesion characterization and may provide additional information on MS lesion heterogeneity.


Assuntos
Encéfalo/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Interpretação de Imagem Assistida por Computador/métodos , Esclerose Múltipla/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Encéfalo/patologia , Doença Crônica , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Substância Branca/patologia
6.
AJNR Am J Neuroradiol ; 36(1): 91-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25169925

RESUMO

BACKGROUND AND PURPOSE: The frequency and amount of intracranial, intradural inflammatory vessel wall enhancement in giant cell arteritis remain unclear. The purpose of this work was to prospectively assess the intracranial extent of vasculitic changes in patients with giant cell arteritis using a dedicated MR imaging protocol optimized for assessment of mural changes of intracranial arteries. MATERIALS AND METHODS: Twenty-eight patients with suspected giant cell arteritis underwent 3T MR imaging. Imaging included a fat-saturated T1WI pre- and postcontrast application optimized for assessment of intradural vessel wall enhancement and high-resolution fat-saturated T1WI to evaluate superficial extracranial vessels. Temporal artery biopsies were available in 11 cases. Vessel wall enhancement of intradural and extracranial vessels was evaluated by 2 observers independently. RESULTS: Twenty patients had giant cell arteritis; 9 cases were biopsy-proved. Clear vessel wall enhancement of superficial extracranial and intradural internal carotid arteries was detected in 16 and 10 patients, respectively. Slight vessel wall enhancement of the vertebral arteries was seen. Of 9 patients with giant cell arteritis with vessel occlusion or stenosis, 2 presented with cerebral ischemic infarcts. Vessel occlusion or stenosis site coincided with the location of vessel wall enhancement of the vertebral arteries in 4 patients and of the intradural ICA in 1 patient. CONCLUSIONS: Vessel wall enhancement of intradural arteries, mainly the ICA, can be regularly found in patients with giant cell arteritis. Mural inflammatory changes of the intradural ICA detected on MR imaging may identify a subgroup of patients with giant cell arteritis and should be further evaluated in clinical studies.


Assuntos
Artérias Cerebrais/patologia , Arterite de Células Gigantes/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Artérias/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
AJNR Am J Neuroradiol ; 36(2): 275-82, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25500313

RESUMO

BACKGROUND AND PURPOSE: In proximal anterior circulation occlusive strokes, collateral flow is essential for good outcome. Collateralized vessel intensity in TOF- and contrast-enhanced MRA is variable due to different acquisition methods. Our purpose was to quantify collateral supply by using flow-weighted signal in TOF-MRA and blood volume-weighted signal in contrast-enhanced MRA to determine each predictive contribution to tissue infarction and reperfusion. MATERIALS AND METHODS: Consecutively (2009-2013), 44 stroke patients with acute proximal anterior circulation occlusion met the inclusion criteria with TOF- and contrast-enhanced MRA and penumbral imaging. Collateralized vessels in the ischemic hemisphere were assessed by TOF- and contrast-enhanced MRA using 2 methods: 1) visual 3-point collateral scoring, and 2) collateral signal quantification by an arterial atlas-based collateral index. Collateral measures were tested by receiver operating characteristic curve and logistic regression against 2 imaging end points of tissue-outcome: final infarct volume and percentage of penumbra saved. RESULTS: Visual collateral scores on contrast-enhanced MRA but not TOF were significantly higher in patients with good outcome. Visual collateral scoring on contrast-enhanced MRA was the best rater-based discriminator for final infarct volume < 90 mL (area under the curve, 0.81; P < .01) and percentage of penumbra saved >50% (area under the curve, 0.67; P = .04). Atlas-based collateral index of contrast-enhanced MRA was the overall best independent discriminator for final infarct volume of <90 mL (area under the curve, 0.94; P < .01). Atlas-based collateral index combining the signal of TOF- and contrast-enhanced MRA was the overall best discriminator for effective reperfusion (percentage of penumbra saved >50%; area under the curve, 0.89; P < .001). CONCLUSIONS: Visual scoring of contrast-enhanced but not TOF-MRA is a reliable predictor of infarct outcome in stroke patients with proximal arterial occlusion. By atlas-based collateral assessment, TOF- and contrast-enhanced MRA both contain predictive signal information for penumbral reperfusion. This could improve risk stratification in further studies.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Infarto Encefálico/diagnóstico , Angiografia por Ressonância Magnética/métodos , Reperfusão , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Circulação Colateral/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Curva ROC
8.
Neuroimage ; 84: 1032-41, 2014 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-24004692

RESUMO

Quantitative transverse relaxation rates in normal aging brain are essential to investigate pathologies associated with iron accumulation and tissue degeneration. Since absolute values depend on imaging methods and magnetic field strengths, continuous evaluation of specific reference values remains requisite. Multi-echo turbo spin echo and multi-echo gradient recalled echo imaging sequences were applied to 66 healthy subjects (18-84years) at 3T to quantify the irreversible (R2), effective (R2*) and reversible (R2'=R2*-R2) transverse relaxation rates. Representative regions-of-interest (ROIs) were determined automatically in gray matter (GM) and white matter (WM) on T1-weighted scans. Phantom experiments of different sized iron-oxide particles were conducted to explore the correlation of R2' related to R2 for the evaluation of the size of iron deposits. R2 decreased with age for the majority of ROIs, but increased for putamen, head of caudate nucleus and nucleus accumbens. R2* and R2' increased with age in deep GM structures except for the thalamus. R2* and R2' showed a distinct dependency on fiber orientation in exemplary WM regions. R2', R2 and R2* were strongly linear proportional to age-related iron content in deep GM with slopes of 0.88, 0.18 and 1.08 in [1/s/mg Fe per 100g wet tissue] and intercepts of 1.69, 9.25 and 10.69 in [1/s], respectively. Linear and non-linear curve fitting of R2' vs. R2 in phantoms revealed increased slopes with increasing particle size. In vivo, averaged R2' vs. R2 data points of patients with Parkinson's disease and progressive supranuclear palsy were above the fitted curves of healthy subjects suggesting larger sized iron deposits in these neurodegenerative diseases. Decreased R2 with age may reflect physiological tissue degeneration, whereas increased R2* and R2' with age most likely denote physiological iron accumulation. The low intercept of R2' vs. iron content suggests a nearly sole sensitivity of R2' to iron in deep GM, potentially allowing a more specific estimation of the iron content than R2 or R2*. Since R2* and R2' depend on the fiber orientation, their feasibility to estimate iron content in WM is challenging. The analysis of R2' related to R2 may provide valuable information about the size of iron deposits.


Assuntos
Envelhecimento/fisiologia , Mapeamento Encefálico , Encéfalo/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
AJNR Am J Neuroradiol ; 34(9): 1697-703, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23538410

RESUMO

BACKGROUND AND PURPOSE: The mismatch between lesions identified in perfusion- and diffusion-weighted MR imaging is typically used to identify tissue at risk of infarction in acute stroke. The purpose of this study was to analyze the variability of mismatch volumes resulting from different time-to-peak or time-to-maximum estimation techniques used for hypoperfused tissue definition. MATERIALS AND METHODS: Data of 50 patients with middle cerebral artery stroke and intracranial vessel occlusion imaged within 6 hours of symptom onset were analyzed. Therefore, 10 different TTP/Tmax techniques and delay thresholds between +2 and +12 seconds were used for calculation of perfusion lesions. Diffusion lesions were semiautomatically segmented and used for mismatch quantification after registration. RESULTS: Mean volumetric differences up to 40 and 100 mL in individual patients were found between the mismatch volumes calculated by the 10 TTP/Tmax estimation techniques for typically used delay thresholds. The application of typical criteria for the identification of patients with a clinically relevant mismatch volume resulted in different mismatch classifications in ≤24% of all cases, depending on the TTP/Tmax estimation method used. CONCLUSIONS: High variations of tissue-at-risk volumes have to be expected when using different TTP/Tmax estimation techniques. An adaption of different techniques by using correction formulas may enable more comparable study results until a standard has been established by agreement.


Assuntos
Algoritmos , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Angiografia por Ressonância Magnética/métodos , Acidente Vascular Cerebral/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
10.
Clin Neuroradiol ; 22(4): 305-13, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22484907

RESUMO

PURPOSE: Few magnetic resonance imaging (MRI) studies of stroke have evaluated the value of visual assessment of perfusion/diffusion mismatch, which is crucial for routine application. In this study an attempt was made to visually assess perfusion lesions resembling the acute clinical situation and identify parameters with the highest interobserver reliability when used to define a perfusion/diffusion mismatch and the highest accuracy for prediction of infarct growth. METHODS: Magnetic resonance imaging was performed within 6 h of symptom onset and again 1-11 days thereafter in 86 consecutive stroke patients who received intravenous thrombolytic therapy. The MRI protocol included diffusion-weighted imaging apparent diffusion coefficient (DWI/ADC), fluid-attenuated inversion recovery (FLAIR) and perfusion imaging (PI). Maps for different perfusion parameters, e.g. cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT) and time to peak (TTP) were calculated. Areas of perfusion deficits of all perfusion parameters were visually compared to corresponding ADCs and final infarct size by two independent observers. RESULTS: The final infarct size was overestimated by TTP (in 81/83 patients by raters 1 and 2, respectively), MTT (82/83) and CBF (65/74) lesions. The ADC lesions were rated smaller than the final infarct size in 43/38 cases by raters 1 and 2 and the CBV decrease was rated to underestimate final infarct size in 40/31 cases. The only significantly increased OR of 3.883 (95 % CI 1.466-10.819, p = 0.004, rater 1)/5.142 (95 % CI 1.828-15.142, p = 0.001, rater 2) for predicting infarct growth was observed for the presence of a CBV > ADC mismatch, which also showed the highest kappa value of 0.407. CONCLUSIONS: All mismatch patterns were prone to high interrater variability when assessed under conditions resembling the clinical setting. Of all tested mismatch patterns the CBV > ADC mismatch was the strongest predictor of lesion growth while visual assessment of TTP and CBF generally resulted in an overestimation of infarct sizes and the presence of a TTP > ADC or CBF > ADC mismatch was not significantly predictive for lesion growth. Visual inspection of these most commonly used mismatch patterns has a low value for the prediction of infarct growth and thus the estimation of the penumbra in ischemic stroke patients.


Assuntos
Infarto Cerebral/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Interpretação de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo/fisiologia , Volume Sanguíneo/fisiologia , Infarto Cerebral/tratamento farmacológico , Feminino , Seguimentos , Humanos , Infarto da Artéria Cerebral Anterior/diagnóstico , Infarto da Artéria Cerebral Anterior/tratamento farmacológico , Infarto da Artéria Cerebral Média/diagnóstico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Prognóstico , Fluxo Sanguíneo Regional/fisiologia , Sensibilidade e Especificidade , Terapia Trombolítica
11.
J Neurol Neurosurg Psychiatry ; 80(10): 1156-8, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19762906

RESUMO

BACKGROUND: Treatment with intravenous tissue plasminogen activator (IV-tPA) is usually not recommended in patients with minor stroke. Clinical and imaging outcome were studied after IV-tPA treatment based on MRI criteria in patients with minor stroke. METHODS: Data were analysed retrospectively of acute ischaemic stroke patients with minor stroke (National Institutes of Health Stroke Scale (NIHSS) score <4). All patients were studied by stroke MRI including perfusion and diffusion weighted imaging (PWI and DWI) and treated with IV-tPA for < or =6 h. Final infarct volume was delineated on follow-up MRI. Clinical outcome was assessed after 90 days using the modified Rankin Scale (mRS). RESULTS: Six patients with a median NIHSS on admission of 2 (range 0-3) were treated with IV-tPA based on MRI criteria. In all patients, occlusion of the middle cerebral artery (MCA) was detected (MCA branch n = 2, MCA trunk n = 3, MCA trifurcation n = 1), and the PWI lesion (41, 25-60 ml) exceeded the DWI lesion (4, 1-23 ml). Final infarct volume was 9 (2-29) ml. Favourable outcome (mRS 0-1) was seen in 5/6 patients and independent outcome (mRS = 2) in one patient. No intracerebral haemorrhages occurred. CONCLUSION: Treatment with IV-tPA based on MRI criteria was safe and appeared to be effective in this small series of patients with minor stroke.


Assuntos
Infarto Encefálico/patologia , Fibrinolíticos/uso terapêutico , Acidente Vascular Cerebral/patologia , Acidente Vascular Cerebral/terapia , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Infarto Encefálico/complicações , Infarto Encefálico/terapia , Estudos de Coortes , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
12.
Mult Scler ; 15(6): 701-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19482862

RESUMO

BACKGROUND AND PURPOSE: T2'-Magnetic resonance imaging (MRI) allows estimation of oxygen metabolism in normal appearing white and gray matter (NAWM and NAGM) and is sensitive to local iron deposition. We hypothesized that T2' imaging is feasible in routine use and reveals differences between MS patients and healthy subjects. METHODS: T2- and T2*-weighted images were acquired in 23 MS patients (Mean age: 36.8, range: 23-58 years) and 23 age-matched healthy subjects. Quantitative T2- and T2*-values were determined in six regions of interest (ROIs). RESULTS: The T2' values in thalamus and caudate nucleus were significantly lower in MS patients than in healthy subjects (139 ms vs 157 ms, P < 0.001 and 97 ms vs 115 ms, P < 0.01). The NAWM in the frontal lobe revealed significant higher T2' values than in healthy subjects (217 ms vs 170 ms, P < 0.001). The subcortical NAWM revealed significant lower T2' values than in healthy subjects (174 ms vs 187 ms, P < 0.028). CONCLUSION: T2' values differed significantly between MS patients and healthy subjects. The reduced T2' values in the basal ganglia are presumably related to higher iron concentration whereas the increased T2' in frontal NAWM most probably reflects reduced tissue metabolism. T2' imaging is feasible for routine-use and promising for monitoring therapy effects.


Assuntos
Imageamento por Ressonância Magnética , Esclerose Múltipla/metabolismo , Fibras Nervosas Mielinizadas/metabolismo , Prosencéfalo/metabolismo , Adulto , Núcleo Caudado/metabolismo , Núcleo Caudado/patologia , Feminino , Lobo Frontal/metabolismo , Lobo Frontal/patologia , Humanos , Ferro/metabolismo , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Fibras Nervosas Mielinizadas/patologia , Neurônios/metabolismo , Neurônios/patologia , Prosencéfalo/patologia , Tálamo/metabolismo , Tálamo/patologia , Adulto Jovem
13.
AJNR Am J Neuroradiol ; 29(5): 950-5, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18272561

RESUMO

BACKGROUND AND PURPOSE: Physiologic age-related T2* and T2' values are required as reference for comparison with disease-related deviations. In our study, T2* and T2' values (T2 values as control) were determined with MR imaging in healthy subjects to determine standard values and investigate age-related changes. MATERIALS AND METHODS: Data of 50 patients without intraparenchymal pathology and 10 acute stroke patients who underwent MR imaging including a T2 and T2* sequence with 3 echotimes were included. After calculation of T2*, T2', and T2 maps, the values of gray matter (GM) and white matter (WM) for each hemisphere were measured in 6 distinct regions of interest (ROIs). RESULTS: There was a negative correlation between age and T2* values in the caudate nucleus (r = -0.34 Pearson correlation; P = .001) and lentiform nucleus (r = -0.67; P = .001) and a positive correlation in the occipital (r = 0.41; P = .001) and subcortical (r = 0.45; P = .001) WM. An age dependency for T2' values was only found for the caudate (r = -0.35; P = .001) and lentiform nucleus (r = -0.69; P = .001). T2' values in acute stroke were lower than normal in all patients with stroke. CONCLUSION: Decrease in T2' and T2* values in GM and increase of T2* values in WM correlate with the progress of brain aging. Explanations for decreasing T2' and T2* values include iron deposition in the caudate and lentiform nucleus. In contrast to T2* values, there is no association of T2' values with the degree of leukoaraiosis. These age-dependent values can be used as a reference in neurovascular diseases and for the discussion of functional MR imaging data.


Assuntos
Envelhecimento/patologia , Encéfalo/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Interpretação de Imagem Assistida por Computador/normas , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/normas , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência
14.
AJNR Am J Neuroradiol ; 28(9): 1755-61, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17885238

RESUMO

BACKGROUND AND PURPOSE: The purpose of this study was to analyze angiographic and clinical results before and after additional endovascular therapy in patients with previously coiled but reopened cerebral aneurysms and to identify possible risk factors for retreatment of an aneurysm. MATERIALS AND METHODS: Follow-up with selective digital subtraction angiography was performed in 323/596 (54.2%) patients harboring 342 aneurysms with a mean follow-up time of 28.6 months. The patients were divided into 3 groups: group A, who remained stable after initial treatment; group B, who showed minor morphologic changes; and group C, who underwent repeat treatment. Univariate and multivariate regression analyses were performed to determine possible risk factors for aneurysmal retreatment. RESULTS: Single or multiple retreatment was performed in 33 of 323 (10.2%) patients. Retreatment of small aneurysms (< or =10 mm) with small necks (< or =4 mm) was performed in 6 of 214 aneurysms. When summarizing all other aneurysms as a "risk group" (n = 128), the odds ratio (OR) for retreatment in the "risk group" was 3.11 (95% CI: 1.43-6.75; P = .004). In patients with residual aneurysm after the first treatment, OR for retreatment was 3.96 (95% CI: 1.48-10.65; P = .006), whereas a neck remnant, clinical presentation, and aneurysmal localization were not predictive. We observed no resulting morbidity and mortality from the 33 retreatment procedures. CONCLUSION: In our series, the retreatment of aneurysmal recurrences was a safe procedure. The best single predictors of aneurysmal recurrence were aneurysmal anatomy (neck width >4 mm and diameter >10 mm) and the presence of a residual aneurysm after initial treatment. A limitation in our study was the significant number of patients lost to follow-up (22.7%).


Assuntos
Embolização Terapêutica/estatística & dados numéricos , Aneurisma Intracraniano/epidemiologia , Aneurisma Intracraniano/terapia , Medição de Risco/métodos , Adolescente , Adulto , Idoso , Criança , Feminino , Seguimentos , Alemanha/epidemiologia , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Prevalência , Prognóstico , Radiografia , Fatores de Risco , Falha de Tratamento , Resultado do Tratamento
15.
Rofo ; 179(1): 17-20, 2007 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-17203439

RESUMO

PURPOSE: Delineation of brain tissue that is at risk but not yet infarcted (penumbra) continues to be a major challenge for stroke imaging. Metabolic characterization of the penumbra might be able to be achieved using blood-oxygen-level-dependent (BOLD) imaging. MATERIALS AND METHODS: We analyzed MRI data from 20 patients within the first 6 hours after stroke onset and after 5-8 days. Among other sequences, the MRI protocol consisted of diffusion-weighted (DWI/ADC = apparent diffusion coefficient) and quantitative T2 and T2* imaging (qT2, qT2*). BOLD images (T2') were calculated using 1/T2' = 1/qT2* - 1/qT2. BOLD lesions were rated by two blinded observers. RESULTS: Based on the primary blinded reading of the BOLD images, the lesion side was rated correctly by observers 1 and 2 in 80/50 % of the cases, incorrectly in 5/40 % of the cases, and rated as not visible in 15/10 % of the cases. After unblinding the observers, the visibility was rated in 45/45 % of the cases as good, in 35/40 % of the cases as reasonable, and in 20/15 % of the cases as insufficient for diagnostic purposes. The sensitivity for subsequent infarct growth was 0.88 (95 % confidence interval, CI 0.47 to 0.99), the specificity was 0.33 (95 % CI 0.07 to 0.70), the positive predictive value (PPV) was 0.54 (95 % CI 0.25 to 0.81), and the negative predictive value (NPV) was 0.75 (95 % CI 0.19 to 0.99). The odds ratio for subsequent infarct growth was 3.5 (95 % CI 0.20 to 115.53). CONCLUSION: Hypo-intense lesions in BOLD imaging were visible and exceeded the lesion in diffusion-weighted imaging in most of the stroke patients. The encouraging results justify further testing of the hypothesis that BOLD lesions, when larger than DWI lesions, are associated with infarct growth from initial DWI to final infarct.


Assuntos
Infarto Encefálico/diagnóstico , Isquemia Encefálica/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Oxigênio/sangue , Acidente Vascular Cerebral/diagnóstico , Doença Aguda , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalos de Confiança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Projetos Piloto , Sensibilidade e Especificidade , Fatores de Tempo
16.
Stroke ; 29(12): 2501-6, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9836758

RESUMO

BACKGROUND AND PURPOSE: In Germany, basic data on stroke morbidity are lacking. If a population-based register in former East Germany is excluded, only routine mortality statistics have thus far provided information on epidemiology of stroke. Therefore, a population-based register of stroke was set up in Southern Germany to determine incidence and case fatality in a defined German population. METHODS: The Erlangen Stroke Project (ESPro) is a prospective community-based study among the 101 450 residents of the city of Erlangen, Bavaria, Germany. Standard definitions and overlapping case-finding methods were used to identify all cases of first-ever stroke in all age-groups, occurring in the 2 years of registration (April 1, 1994, to March 31, 1996). All identified cases of first-ever strokes were followed up at 3 and 12 months from onset. RESULTS: During 2 years of registration, 354 first-ever-in-a-lifetime strokes (FELS) were registered. The diagnosis and stroke type were confirmed by CT scan in 95% of cases. Fifty-one percent of all FELS occurred in the age group >/=75 years of age. The crude annual incidence rate was 1.74 per 1000 (1.47 for men and 2.01 for women). After age-adjustment to the European population, the incidence rate was 1.34 per 1000 (1.48 for men and 1. 25 for women). The annual crude incidence rate of cerebral infarction was 1.37/1000, intracerebral hemorrhage 0.24/1000, subarachnoid hemorrhage 0.06/1000, and unspecified stroke 0.08/1000. Overall case fatality at 28 days was 19.4%, at 3 months it was 28.5%, and at 1 year 37.3%. CONCLUSIONS: The first prospective community-based stroke register including all age groups in Germany revealed incidence rates of stroke similar to those reported from other population-based studies in western industrialized countries, but lower than that observed in former East Germany.


Assuntos
Transtornos Cerebrovasculares/epidemiologia , Transtornos Cerebrovasculares/mortalidade , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Transtornos Cerebrovasculares/classificação , Criança , Pré-Escolar , Feminino , Alemanha , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros , Distribuição por Sexo , Fatores de Tempo
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