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1.
Analyst ; 137(7): 1584-95, 2012 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-22158509

RESUMO

In this study the potential of new imaging techniques such as Magnetic Resonance Imaging (MRI), Matrix-Assisted Laser Desorption/Ionization (MALDI) profiling mass spectrometry ("MALDI Profiling") and Fourier Transform Infrared (FTIR) spectroscopic imaging was evaluated to study morphological and molecular patterns of the potential medicinal fungus Hericium coralloides. For interpretation, the MALDI profiling, FTIR imaging and MRI results were correlated with histological information gained from Scanning Electron Microscopy (SEM) and Light Microscopy (LM). Additionally we tested several evaluation processes and optimized the methodology for use of complex FTIR images to monitor molecular patterns. It is demonstrated that the combination of these spectroscopic methods enables to gain a more distinct picture concerning morphology and distribution of active ingredients. We were able to obtain high quality FTIR imaging and MALDI-profiling results and to distinguish different tissue types with their chemical ingredients. Beside this, we have created a 3-D reconstruction of a mature Hericium basidioma, based on the MRI dataset: analyses allowed, for the first time, a realistic approximation of the "evolutionary effectiveness" of this bizarrely formed basidioma type, concerning the investment of sterile tissue and its reproductive output (production of basidiospores).


Assuntos
Basidiomycota/química , Basidiomycota/citologia , Química Farmacêutica , Imagem Molecular , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectroscopia de Infravermelho com Transformada de Fourier
2.
Schmerz ; 25(5): 522-33, 2011 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-21901567

RESUMO

BACKGROUND: Anesthesiology departments were often integrated into the primary formation of palliative activities in Germany. The aim of this study was to present the current integration of anesthesiology departments into palliative care activities in Germany. METHODS: The objective was to determine current activities of anesthesiology departments in in-hospital palliative care. A quantitative study was carried out based on a self-administered structured questionnaire used during telephone interviews. RESULTS: A total of 168 out of 244 hospitals consented to participate in the study and the response rate was 69%. In-hospital palliative care activities were reported for most of the surveyed hospitals. Only two hospitals in the maximum level of care reported no activities. Participation in these activities by anesthesiology departments was described in up to 92%. Historically, most activities are due to the commitment of individuals, whereas the development of palliative care of cancer pain services and hospital support teams took place in the university hospitals by 2005. CONCLUSIONS: Until 2005 many university palliative care activities had their origins in cancer pain services. These were often integrated into anesthesiology departments. Currently, anesthesiology departments work as an integrative part of palliative medicine. However, it appears from the present results that there is a domination of internal medicine (especially hematology and oncology) in palliative activities in German hospitals. This allows the focus of palliative activities to be formed by subjective specialist interests. Such a state seems to be reduced by the integration of anesthesiology departments because of their neutrality with respect to faculty-specific medical interests. Advantages or disadvantages of these circumstances are not considered by the present investigation.


Assuntos
Anestesiologia , Cuidados Paliativos/métodos , Anestesiologia/educação , Comportamento Cooperativo , Currículo , Coleta de Dados , Educação Médica Continuada , Alemanha , Pesquisa sobre Serviços de Saúde , Hospitais Gerais , Hospitais Especializados , Hospitais Universitários , Humanos , Comunicação Interdisciplinar , Neoplasias/fisiopatologia , Medição da Dor , Equipe de Assistência ao Paciente , Inquéritos e Questionários
3.
J Neurol Neurosurg Psychiatry ; 79(5): 547-52, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-17682014

RESUMO

PURPOSE: Ulegyria refers to cerebral cortex scarring, which results from a perinatal ischaemic brain injury. It presents with a characteristic gyral pattern: small circumvolutions with atrophy at sulci bottom and spared apex. Ulegyria is frequently associated with epilepsy, cerebral palsy and mental disability. We analysed electroclinical and MRI features in patients with ulegyria and epilepsy. PATIENTS AND METHODS: We reviewed 25 patients (14 males/11 females) with ulegyria and epilepsy from the database (about 5000 patients with epilepsy) of our unit. Patients were examined clinically, underwent high resolution MRI, EEG recordings, positron emission tomography, single photon emission computed tomography and neuropsychological testing. Two patients with refractory seizures underwent epilepsy surgery. RESULTS: Mean age of patients was 34 years (5-66) at the reassessment time. The majority (16/25, 64%) had a history of perinatal asphyxia. 15 patients had delayed developmental milestones; 20 had learning disabilities and five patients were severely disabled. Mean age at seizure onset was 4.2 years (1-18). 17 patients (68%) had medically intractable epilepsy. 11 patients (44%) had occipital lobe seizures. The majority (n = 24, 96%) had parieto-occipital lesions on MRI. In 13 patients (52%), ulegyria was bilateral. 12 patients (48%) had hippocampal sclerosis. Two patients underwent epilepsy surgery with an excellent postoperative outcome (Engel class IA and IC). CONCLUSION: Patients with ulegyria often have a history of perinatal asphyxia and present with pharmacoresistant seizures. Their presurgical assessment is complicated because of frequent dual pathology (hippocampal sclerosis) and bilateral lesions.


Assuntos
Asfixia Neonatal/complicações , Dano Encefálico Crônico/diagnóstico , Isquemia Encefálica/complicações , Córtex Cerebral/patologia , Cicatriz/diagnóstico , Imagem Ecoplanar , Eletroencefalografia , Epilepsias Parciais/diagnóstico , Hipóxia Fetal/complicações , Imageamento por Ressonância Magnética , Exame Neurológico , Adolescente , Adulto , Idoso , Asfixia Neonatal/patologia , Atrofia , Dano Encefálico Crônico/patologia , Isquemia Encefálica/patologia , Criança , Pré-Escolar , Epilepsias Parciais/patologia , Feminino , Hipóxia Fetal/patologia , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Neurônios/patologia
4.
Br J Radiol ; 91(1088): 20170337, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29376731

RESUMO

The term "paraspinal arteriovenous shunts" (PAVSs) summarizes an inhomogeneous variety of rare vascular disorders. PAVSs have been observed as congenital or acquired lesions. The clinical course of PAVSs may be asymptomatic or present with life-threatening symptoms. Based on a collection of individual cases from three institutions and a literature evaluation, we propose the following classification: PAVSs that are part of a genetic syndrome are separated from "isolated" PAVSs. Isolated PAVSs are subdivided into "acquired", "traumatic" and "congenital" without an identifiable genetic hereditary disorder. The subgroups are differentiated by the route of venous drainage, being exclusively extraspinal or involving intraspinal veins. PAVSs associated to a genetic syndrome may either have a metameric link or occur together with a systemic genetic disorder. Again extra-vs intraspinal venous drainage is differentiated. The indication for treatment is based on individual circumstances (e.g. myelon compression, vascular bruit, high volume output cardiac failure). Most PAVSs can be treated by endovascular means using detachable coils, liquid embolic agents or stents and derivates.


Assuntos
Fístula Arteriovenosa/classificação , Fístula Arteriovenosa/etiologia , Adulto , Idoso , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Coluna Vertebral/irrigação sanguínea
5.
Epileptic Disord ; 9(1): 71-6, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17307715

RESUMO

INTRODUCTION: There are sporadic reports of unilateral polymicrogyria with ipsilateral hemiatrophic cerebri associated with epilepsy, focal neurological deficit and mental retardation. The mechanisms which cause this condition are not well understood. The aim of our study was to delineate further, clinical and neuroimaging features of this malformation of cortical development and to explore its possible etiological background. PATIENTS AND METHODS: Four patients (two males and two females), aged from 23 to 31 years (mean age range 27.5 years) were evaluated. Subjects underwent clinical, electrophysiological, neuropsychological and high resolution magnetic resonance imaging assessment. RESULTS: No significant perinatal event or exposure to intrauterine infection was noted. None suffered from birth asphyxia or ischemic injury. The parents of two patients were first cousins. Every subject had delayed developmental milestones, mental disability and congenital, non-progressive, spastic hemiparesis. They had epilepsy with seizure-onset ranging from three months to 17 years (mean 6.8 years); two had intractable seizures. In all patients, unilateral, right-sided polymicrogyria was associated with ipsilateral cerebral hemiatrophy. Polymicrogyria involved mainly anterior perisylvian areas; occipital regions were relatively spared. CONCLUSION: The evaluated patients showed homogenous clinical and neuroimaging characteristics. We support the idea that the disorder could constitute a clinical entity with an underlying genetic cause.


Assuntos
Córtex Cerebral/anormalidades , Epilepsia/etiologia , Deficiência Intelectual/etiologia , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Paresia/etiologia , Síndrome
6.
J Hand Surg Br ; 30(5): 530-3, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16055246

RESUMO

We studied cortical activation patterns by functional MRI in a patient who received bilateral hand transplantation after amputation 6 years ago and in a patient who had received unilateral hand replantation within 2 hours after amputation. In the early postoperative period, the patient who had had the hand transplantation revealed strong activation of a higher motor area, only weak activation of the primary sensorimotor motor cortex and no activation of the primary somatosensory cortex. At 1-year follow-up, a small increase in primary sensorimotor motor cortex activation was observed. Activation of the primary somatosensory cortex was only seen at the 2 year follow-up. By contrast, after hand replantation, the activation pattern was similar to that of the uninjured hand within 6 weeks. This included activation of the primary sensorimotor motor cortex, higher motor areas and primary somatosensory cortex. Transplantation after long-standing amputation results in cortical reorganization occurring over a 2-year period. In contrast, hand replantation within a few hours preserves a normal activation pattern.


Assuntos
Mãos/cirurgia , Córtex Motor/fisiologia , Reimplante , Adulto , Feminino , Mãos/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Movimento/fisiologia , Transplante Homólogo
7.
Biol Psychiatry ; 33(8-9): 651-4, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8392387

RESUMO

Animal studies show that cerebral lactate increases after electrically induced seizures. We investigated three adult psychiatric patients by means of localized proton and phosphorous magnetic resonance spectroscopy in order to evaluate if such effects can be observed after electroconvulsive therapy (ECT). None of the patients had changes in cerebral energy metabolism following ECT. Within the limitations of in-vivo spectroscopy in a clinical setting, our results suggest that if lactate production increases after ECT, this effect is either very short or increased perfusion causes an efficient efflux of cerebral lactate.


Assuntos
Encéfalo/metabolismo , Transtorno Depressivo/metabolismo , Eletroconvulsoterapia , Transtorno Depressivo/terapia , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Pessoa de Meia-Idade , Fósforo , Prótons
8.
Neurology ; 54(8): 1670-6, 2000 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-10762512

RESUMO

OBJECTIVE: To determine the value of vascular endothelial growth factor (VEGF) in CSF as a marker for carcinomatous meningitis (CM). METHODS: The concentration of VEGF was measured by ELISA in matched samples of CSF and serum collected from 162 patients. These included patients with solid tumors with CM (n = 11) or brain metastases without concomitant CM (n = 12), paraneoplastic neurologic syndromes (n = 4), viral (n = 15) and bacterial (n = 20) meningitis, and a variety of non-neoplastic and noninfectious neurologic diseases (n = 100). Using CSF/serum albumin ratios, the VEGF index was calculated to estimate the proportion of intrathecally produced VEGF. Immunohistochemical staining for VEGF was performed in a brain metastasis from a mammary carcinoma associated with CM. RESULTS: High VEGF levels (median 6,794.8 pg/mL) were found in CSF of all patients with CM, whereas VEGF levels in matched sera were comparable to other disease groups. In patients with CM, the concentration of VEGF in CSF decreased significantly following antineoplastic treatment. In CSF samples from patients with brain metastases without concomitant CM, VEGF was not detectable. Median VEGF concentration in CSF from patients with acute bacterial meningitis was 38.6 pg/mL, with only 9 of these 17 patients showing detectable VEGF levels in CSF. The VEGF indices in patients with bacterial meningitis were significantly lower than in tumor patients with CM (<22.8 versus >62.3), suggesting that the proportion of intrathecally produced VEGF is much higher in patients with CM as compared with patients with bacterial meningitis. Patients without neoplastic or infectious neurologic disorders consistently showed VEGF levels in CSF below the assay detection limit of 25 pg/mL. Immunohistochemistry revealed strong cytoplasmic staining for VEGF in a metastatic lesion from breast cancer infiltrating the meninges. CONCLUSION: In patients with carcinomatous meningitis, significant amounts of VEGF are released into CSF. This study yields preliminary evidence that VEGF in CSF may be a useful biologic marker for both the diagnosis and evaluation of treatment response in carcinomatous meningitis.


Assuntos
Carcinoma/complicações , Carcinoma/diagnóstico , Fatores de Crescimento Endotelial/líquido cefalorraquidiano , Linfocinas/líquido cefalorraquidiano , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/diagnóstico , Meningite/etiologia , Adolescente , Adulto , Idoso , Biomarcadores , Carcinoma/metabolismo , Carcinoma/secundário , Diagnóstico Diferencial , Fatores de Crescimento Endotelial/sangue , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imuno-Histoquímica , Linfocinas/sangue , Masculino , Neoplasias Meníngeas/metabolismo , Neoplasias Meníngeas/secundário , Meningite/diagnóstico , Meningite/metabolismo , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Albumina Sérica/líquido cefalorraquidiano , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
9.
Schizophr Res ; 31(2-3): 73-81, 1998 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-9689711

RESUMO

Using magnetic resonance imaging of the brain, we examined volumetric measurements of total brain, hemispheres, lateral ventricles and the hippocampus/amygdala complex in male subjects (41 first-episode schizophrenics, 30 chronic schizophrenic patients and 32 healthy controls). We found significantly smaller total brain size in the chronic schizophrenic group, significantly larger lateral ventricles in both patient groups and hippocampal volume reduction bilaterally in first-episode patients (-13.2% left, -12.05% right) and chronic patients (-10.6% left, -10.5% right) compared to controls--irrespective of diagnostic subtype, family history for psychiatric diseases, psychopathology, duration of illness or age at onset.


Assuntos
Hipocampo/patologia , Esquizofrenia/patologia , Adulto , Tonsila do Cerebelo/patologia , Encéfalo/patologia , Estudos de Casos e Controles , Córtex Cerebral/patologia , Ventrículos Cerebrais/patologia , Doença Crônica , Progressão da Doença , Humanos , Modelos Lineares , Imageamento por Ressonância Magnética , Masculino
10.
Neurosci Lett ; 344(3): 169-72, 2003 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-12812832

RESUMO

Sex differences in mental rotation tasks, favoring men, have been noted in behavioral studies and functional imaging studies. In the present study ten female and ten male volunteers underwent functional magnetic resonance imaging in a conventional block design. Regions of activation were detected after performance of a mental rotation task inside the scanner. In contrast to previous studies, confounding factors such as performance differences between genders or high error rates were excluded. Men showed significantly stronger parietal activation, while women showed significantly greater right frontal activation. Our results point to gender specific differences in the neuropsychological processes involved in mental rotation tasks.


Assuntos
Encéfalo/fisiologia , Cognição , Percepção Visual , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Rotação , Fatores Sexuais
11.
Neurosci Lett ; 352(3): 191-4, 2003 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-14625017

RESUMO

Sex differences in executive speech tasks, favoring women, have been noted in behavioral studies and functional imaging studies. In the present study ten female and ten male volunteers underwent functional magnetic resonance imaging in a conventional block design. All subjects were selected on the basis of high performance on the verbal fluency task. Regions of activation were detected after performance of a covert lexical verbal fluency task inside the scanner. Men and women who did not differ significantly in verbal fluency task performance showed a very similar pattern of brain activation. Our data argue against genuine between-sex differences in cerebral activation patterns during lexical verbal fluency activities when confounding factors like performance differences are excluded.


Assuntos
Encéfalo/fisiologia , Testes de Linguagem/estatística & dados numéricos , Imageamento por Ressonância Magnética/métodos , Caracteres Sexuais , Adulto , Feminino , Humanos , Masculino
12.
AJNR Am J Neuroradiol ; 15(1): 145-50, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8141046

RESUMO

PURPOSE: To gain further insight into the pathogenesis of progressive facial hemiatrophy, a sporadic disease of unclear etiology characterized by shrinking and deformation of one side of the face. METHODS: We investigated possible brain involvement. MR of the head and face was performed in three female patients with progressive facial hemiatrophy. The central-nervous-system findings were correlated to a clinical protocol and a review of the literature. RESULTS: One patient with epilepsy had abnormal brain findings confined to the cerebral hemisphere homolateral to the facial hemiatrophy. These consisted of monoventricular enlargement, meningocortical dysmorphia, and white-matter changes. CONCLUSIONS: These MR findings, and corresponding neuroradiologic data disclosed by the review, indicate that homolateral hemiatrophy occasionally occurs in a subgroup of patients with progressive facial hemiatrophy. The MR features do not seem consistent with an underlying simple or nutritive atrophic process. We propose chronic localized meningoencephalitis with vascular involvement as a possible underlying cause of the occasional brain involvement in progressive facial hemiatrophy.


Assuntos
Encéfalo/patologia , Hemiatrofia Facial/patologia , Imageamento por Ressonância Magnética , Adulto , Hemiatrofia Facial/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade
13.
J Neurol Sci ; 108(1): 35-8, 1992 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1624950

RESUMO

Water-suppressed proton magnetic resonance spectroscopy which has recently shown diagnostic potential in human stroke victims was performed in two patients who had suffered a hemispheric transient ischemic attack. Localized spectra were targeted from routine MR images. In one patient lactate could be observed 8 weeks after a transient ischemic attack. Lactate concentration was low compared with that of a patient who had suffered acute stroke. The other TIA patient did not show evidence of lactate production. Although these observations are preliminary, we demonstrated that localized in vivo proton spectroscopy can detect persistent biochemical alterations after transient ischemic attacks. We suggest that non-invasive in vivo proton spectroscopy will become a useful method in diagnosis and management of TIA in the future.


Assuntos
Encéfalo/patologia , Ataque Isquêmico Transitório/patologia , Imageamento por Ressonância Magnética/métodos , Idoso , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análise , Química Encefálica , Feminino , Humanos , Ataque Isquêmico Transitório/metabolismo , Lactatos/análise , Ácido Láctico , Masculino , Pessoa de Meia-Idade
14.
J Neurol Sci ; 111(1): 20-5, 1992 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1402994

RESUMO

We present 3 cases and a review of the literature to demonstrate the current state of clinical diagnosis and therapy of superficial siderosis of the central nervous system. Typical symptoms were progressive cerebellar ataxia, spasticity and hearing loss. Repeated subarachnoid hemorrhage was indicated by persistent xanthochromia of the cerebrospinal fluid and confirmed by the presence of erythrophages, siderophages and iron-containing pigments. Deposition of free iron and hemosiderin in pial and subpial structures leads to intoxication of the central nervous system and represents the pathophysiological mechanism of superficial siderosis. Hypointensity of the marginal zones of the central nervous system on T2 weighted MR images indicates an iron-induced susceptibility effect and seems pathognomonic for superficial siderosis. In 39 of the 43 previously described cases superficial siderosis was verified by biopsy or autopsy. Today magnetic resonance imaging enables diagnosis at an early stage of the disease. Therapeutic management requires the elimination of any potential source of bleeding. In patients with unknown etiology no proofed therapy is yet available.


Assuntos
Doenças do Sistema Nervoso Central/patologia , Siderose/patologia , Idoso , Doenças do Sistema Nervoso Central/sangue , Doenças do Sistema Nervoso Central/líquido cefalorraquidiano , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Siderose/sangue , Siderose/líquido cefalorraquidiano , Tomografia Computadorizada por Raios X
15.
Neurosurgery ; 40(5): 1050-7; discussion 1057-8, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9149264

RESUMO

OBJECTIVE: We investigated the compatibility of magnetically adjustable cerebrospinal fluid valves with clinical magnetic resonance imaging. Torque acting on the valves, subjective sensations of valve-carrying volunteers, extension of artifacts on acquired images, changes in valve pressure setting, and accurate valve function after repeated exposure to the magnetic field were tested. METHODS: Two externally adjustable differential pressure valves, i.e., the Codman-Medos programmable valve (Medos S.A., Le Locle, Switzerland) (n = 5) and the Sophy programmable pressure valve (Sophysa, Orsay, France) (Model SP3, n = 4; Model SU8, n = 3; and Model SM8, n = 2) were exposed to the magnetic fields of 1.5-T clinical scanners. Ferromagnetic properties were investigated according to an established protocol. Subjective sensations during positioning and scanning and image artifacts were investigated using standard clinical imaging protocols. Changes in opening pressure setting during repeated magnetic field exposure were examined using valves affixed to a dummy. RESULTS: Deflection forces measured 117 dynes in the Medos valve, and 2439 (Model SP3), 2172 (Model SU8) and 1914 (Model SM8) dynes in the Sophy valves. Torque during positioning and during imaging was reported for the Sophy valves. Distortion of the magnetic field with artifacts on acquired images ranged 6 x 6 x 12 cm around the Sophy valve and 4 x 4 x 4 cm around the Medos valves. Artifact extension increased with longer TE times on T2-weighted images and when using gradient-echo sequences. The pressure setting of the Medos valves did not change in 31 of 88 tests. Below 170 mm H2O, the maximal disadjustment was 60 mm H2O in each direction. Minor changes of the pressure setting were observed at 50 and 30 mm H2O. In 11 of 15 tests at 200 mm H2O, the setting after magnetic field exposure was below 30 mm H2O. One Medos valve could no longer be programmed after being exposed four times to the static magnetic field. Sophy valves remained at or changed to "high" in 68 of 81 tests and to "low" in 9. All Sophy valves exhibited paramagnetic behavior after the tests. All remained programmable. Observed changes always occurred within the safety area of the magnet. CONCLUSION: Subjective disturbances resulting from paramagnetic valve behavior are absent in Medos valves and are minor in Sophy valves. Image artifacts require careful planning of valve position. Artifacts observed in magnetic resonance imaging are less disturbing than those observed in computed tomography. Medos valves are more stable regarding disadjustment than are Sophy valves. Radiological control of valve setting after exposure to the magnetic field is mandatory in both. The 0.5-mT safety line encircling the area that patients with pacemakers should not enter is a useful safety borderline for patients with pressure-adjustable valves. Failure of the programming mechanism of one Medos valve after several exposures to the magnetic field requires clarification.


Assuntos
Pressão do Líquido Cefalorraquidiano/fisiologia , Derivações do Líquido Cefalorraquidiano/instrumentação , Imageamento por Ressonância Magnética/instrumentação , Software , Artefatos , Desenho de Equipamento , Análise de Falha de Equipamento , Humanos , Imagens de Fantasmas
16.
J Neural Transm Suppl ; 47: 143-53, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8841962

RESUMO

Up to now, computerized tomography (CT) and MR-imaging have been used for the morphological assessment of dementia patients, while MRI has become the structure imaging modality of choice. With the advent of fast and ultrafast sequences provided by higher gradient field strengths, functional MR studies like diffusion, perfusion and activation studies become available. The greatest advantage of MR is its versatility including MR-imaging, 3D postprocessing, MR-volumetry, MR-spectroscopy, MR-angiography, MR-perfusion and diffusion imaging as well as functional MRI activation studies. The application of the multimodal MR-technology in dementia disorders has already began and has to be validated in clinical practice. The multimodality of MR represents a diagnostic challenge for the future with the hope, that the diagnostic efficacy, which has to be proven, is also followed by an improvement of patients care and prognosis.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Demência/patologia , Adolescente , Adulto , Encefalopatias/patologia , Demência Vascular/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
17.
J Neurosurg ; 88(5): 809-16, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9576247

RESUMO

OBJECT: In this retrospective study, the authors analyzed the frequency, anatomical distribution, and appearance of traumatic brain lesions in 42 patients in a posttraumatic persistent vegetative state. METHODS: Cerebral magnetic resonance (MR) imaging was used to detect the number of lesions, which ranged from as few as five to as many as 19, with a mean of 11 lesions. In all 42 cases there was evidence on MR imaging of diffuse axonal injury, and injury to the corpus callosum was detected in all patients. The second most common area of diffuse axonal injury involved the dorsolateral aspect of the rostral brainstem (74% of patients). In addition, 65% of these patients exhibited white matter injury in the corona radiata and the frontal and temporal lobes. Lesions to the basal ganglia or thalamus were seen in 52% and 40% of patients, respectively. Magnetic resonance imaging showed some evidence of cortical contusion in 48% of patients in this study; the frontal and temporal lobes were most frequently involved. Injury to the parahippocampal gyrus was detected in 45% of patients; in this subgroup there was an 80% incidence of contralateral peduncular lesions in the midbrain. The most common pattern of injury (74% in this series) was the combination of focal lesions of the corpus callosum and the dorsolateral brainstem. In patients with no evidence of diffuse axonal injury in the upper brainstem (26% in this series), callosal lesions were most often associated with basal ganglia lesions. Lesions of the corona radiata and lobar white matter were equally distributed in patients with or without dorsolateral brainstem injury. Moreover, cortical contusions and thalamic, parahippocampal, and cerebral peduncular lesions were also similarly distributed in both groups. CONCLUSIONS: The data indicate that diffuse axonal injury may be the major form of primary brain damage in the posttraumatic persistent vegetative state. In addition, the authors demonstrated in this study that MR imaging, in conjunction with a precise clinical correlation, may provide useful supportive information for the accurate diagnosis of a persistent vegetative state after traumatic brain injury.


Assuntos
Lesões Encefálicas/etiologia , Traumatismos Cranianos Fechados/complicações , Imageamento por Ressonância Magnética , Estado Vegetativo Persistente/etiologia , Adolescente , Adulto , Axônios/patologia , Gânglios da Base/lesões , Gânglios da Base/patologia , Gânglios da Base/fisiopatologia , Concussão Encefálica/etiologia , Concussão Encefálica/patologia , Concussão Encefálica/fisiopatologia , Lesões Encefálicas/patologia , Lesões Encefálicas/fisiopatologia , Tronco Encefálico/lesões , Tronco Encefálico/patologia , Tronco Encefálico/fisiopatologia , Córtex Cerebral/lesões , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Corpo Caloso/lesões , Corpo Caloso/patologia , Corpo Caloso/fisiopatologia , Giro Denteado/lesões , Giro Denteado/patologia , Giro Denteado/fisiopatologia , Feminino , Seguimentos , Lobo Frontal/lesões , Lobo Frontal/patologia , Lobo Frontal/fisiopatologia , Hipocampo/lesões , Hipocampo/patologia , Hipocampo/fisiopatologia , Humanos , Masculino , Mesencéfalo/lesões , Mesencéfalo/patologia , Mesencéfalo/fisiopatologia , Fibras Nervosas Mielinizadas/patologia , Estado Vegetativo Persistente/patologia , Estado Vegetativo Persistente/fisiopatologia , Estudos Retrospectivos , Lobo Temporal/lesões , Lobo Temporal/patologia , Lobo Temporal/fisiopatologia , Tálamo/lesões , Tálamo/patologia , Tálamo/fisiopatologia
18.
Resuscitation ; 47(1): 41-9, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11004380

RESUMO

PURPOSE: To report a case of cerebral ischemia confirmed by magnetic resonance imaging after successful cardiopulmonary resuscitation (CPR) complicated by acute respiratory injury. MATERIALS AND METHODS: After 4 min of cardiac arrest, followed by 3 min of basic life support CPR, a female pig weighing 38 kg received every 5 min vasopressin (0.4, 0.4 and 0.8 U/kg). After 22 min of cardiac arrest, including 18 min of CPR, one defibrillation attempt employing 100 J resulted in return of spontaneous circulation. Neurological evaluation was performed 24 and 96 h after successful CPR. Magnetic resonance imaging was carried out 4 days after CPR using a clinical 1.5 T scanner. The magnetic resonance imaging protocol consisted of fast spinecho T2-weighted, as well as spinecho T1-weighted imaging of the brain. RESULTS: CPR with vasopressin resulted in excellent coronary perfusion pressure ranging between 35 and 60 mm Hg throughout CPR. Eight minutes after initiation of chest compressions, bleeding out of the tracheal tube occurred. This was later confirmed as originating from bilateral bloody pulmonary infiltrations, resulting in acute respiratory injury in the post-resuscitation phase. Ninety-six hours after successful CPR, magnetic resonance imaging revealed bilateral diffuse cerebral vasogenic edema. CONCLUSION: Although excellent coronary perfusion pressure renders a return of spontaneous circulation more likely, complications such as acute respiratory injury in the post-resuscitation phase have to be managed carefully in order to ensure good neurological recovery from cardiac arrest.


Assuntos
Reanimação Cardiopulmonar , Circulação Coronária , Sistema Nervoso/fisiopatologia , Doença Aguda , Animais , Encéfalo/patologia , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/fisiopatologia , Feminino , Parada Cardíaca/complicações , Parada Cardíaca/terapia , Hemorragia/etiologia , Intestino Delgado/patologia , Pneumopatias/etiologia , Imageamento por Ressonância Magnética , Miocárdio/patologia , Transtornos Respiratórios/etiologia , Análise de Sobrevida , Suínos , Fatores de Tempo , Falha de Tratamento
19.
Neurol Res ; 22(2): 145-50, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10763500

RESUMO

The decrease in intracellular creatine concentration in Duchenne muscular dystrophy may contribute to the deterioration of intracellular energy homeostasis and may thus be one of the factors aggravating muscle weakness and degeneration. Oral creatine supplementation should have potential in alleviating the clinical symptoms. To test this hypothesis, creatine was orally administered over a period of 155 days to a 9-year-old patient with Duchenne muscular dystrophy. In accordance with previous investigations on normal subjects and trained athletes, the patient experienced improved muscle performance during creatine supplementation. Further evidence supporting this hypothesis derived from plasma creatine kinase and lactate dehydrogenase activities and repeated 31P magnetic resonance spectroscopy of the gastrocnemius muscle. These preliminary observations indicate a potential role for creatine supplementation in the symptomatic therapy of patients with muscle disease.


Assuntos
Creatina/uso terapêutico , Distrofia Muscular de Duchenne/tratamento farmacológico , Administração Oral , Criança , Creatina/sangue , Creatina Quinase/sangue , Exercício Físico , Humanos , Membranas Intracelulares/metabolismo , L-Lactato Desidrogenase/sangue , Espectroscopia de Ressonância Magnética , Músculo Esquelético/metabolismo , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/metabolismo , Fósforo/metabolismo , Isótopos de Fósforo
20.
J Neuroimaging ; 9(1): 34-8, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9922722

RESUMO

Transcranial Doppler (TCD) sonography combines the advantages of real-time hemodynamic information, cost-effectiveness, and bedside application. However, measurements can be difficult to reproduce because the spatial resolution and the determination of insonation angles are limited. The purpose of this study was to use the high anatomic resolution of three-dimensional (3D) magnetic resonance angiography (MRA) images for the stereotactic guidance of TCD in order to improve the accuracy and reproducibility of TCD examinations. The MRA examinations were performed on a 1.5 T scanner using a 3D flow compensated gradient-echo sequence. A noninvasive stereotactic mask was used for image registration. The MRA data were then transferred to a personal computer. An infrared tracking system registered the position of the head and the ultrasound probe during TCD. This enabled the authors to superimpose a virtual ultrasound beam onto the MRA projections of the intracranial arteries displayed on the monitor of the personal computer. This allows the examiner to easily identify the insonated intracranial artery and displays the insonation angle. In volunteer examinations (n = 10), the accuracy and reproducibility for the localization of specific vessel segments was 2.48 mm for the middle cerebral artery and 2.81 mm for all insonated intracranial arteries (middle cerebral artery, anterior cerebral artery, internal carotid artery, and posterior cerebral artery). Without navigation the reproducibility of vessel segment insonation dropped to 4.7 mm for the middle cerebral artery and to 4.84 mm for all vessels. The authors conclude that 3D MRA, acquired as an initial procedure in patients with intracranial vascular disorders, can be used to provide stereotactic guidance for repeated TCD examinations. This facilitates the reproducible insonation of specific vessel segments.


Assuntos
Artéria Carótida Interna/diagnóstico por imagem , Artérias Cerebrais/diagnóstico por imagem , Angiografia por Ressonância Magnética , Ultrassonografia Doppler Transcraniana/métodos , Adulto , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Reprodutibilidade dos Testes , Técnicas Estereotáxicas
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