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1.
AJNR Am J Neuroradiol ; 44(7): 807-813, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37385679

RESUMO

BACKGROUND AND PURPOSE: Early identification of the etiology of spontaneous acute intracerebral hemorrhage is essential for appropriate management. This study aimed to develop an imaging model to identify cavernoma-related hematomas. MATERIALS AND METHODS: Patients 1-55 years of age with acute (≤7 days) spontaneous intracerebral hemorrhage were included. Two neuroradiologists reviewed CT and MR imaging data and assessed the characteristics of hematomas, including their shape (spherical/ovoid or not), their regular or irregular margins, and associated abnormalities including extralesional hemorrhage and peripheral rim enhancement. Imaging findings were correlated with etiology. The study population was randomly split to provide a training sample (50%) and a validation sample (50%). From the training sample, univariate and multivariate logistic regression was performed to identify factors predictive of cavernomas, and a decision tree was built. Its performance was assessed using the validation sample. RESULTS: Four hundred seventy-eight patients were included, of whom 85 had hemorrhagic cavernomas. In multivariate analysis, cavernoma-related hematomas were associated with spherical/ovoid shape (P < .001), regular margins (P = .009), absence of extralesional hemorrhage (P = .01), and absence of peripheral rim enhancement (P = .002). These criteria were included in the decision tree model. The validation sample (n = 239) had the following performance: diagnostic accuracy of 96.1% (95% CI, 92.2%-98.4%), sensitivity of 97.95% (95% CI, 95.8%-98.9%), specificity of 89.5% (95% CI, 75.2%-97.0%), positive predictive value of 97.7% (95% CI, 94.3%-99.1%), and negative predictive value of 94.4% (95% CI, 81.0%-98.5%). CONCLUSIONS: An imaging model including ovoid/spherical shape, regular margins, absence of extralesional hemorrhage, and absence of peripheral rim enhancement accurately identifies cavernoma-related acute spontaneous cerebral hematomas in young patients.


Assuntos
Hemorragia Cerebral , Hematoma , Humanos , Hemorragia Cerebral/etiologia , Hemorragia Cerebral/complicações , Diagnóstico Precoce , Hematoma/diagnóstico por imagem , Imageamento por Ressonância Magnética , Valor Preditivo dos Testes , Lactente , Pré-Escolar , Criança , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade
2.
Rev Neurol (Paris) ; 178(6): 539-545, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35148908

RESUMO

INTRODUCTION: We performed a non-inferiority study comparing magnetic resonance angiography (MRA) techniques including contrast-enhanced (CE) and time-of-flight (TOF) with brain digital subtraction arteriography (DSA) in localizing occlusion sites in acute ischemic stroke (AIS) with a prespecified inferiority margin taking into account thrombus migration. MATERIALS AND METHODS: HIBISCUS-STROKE (CoHort of Patients to Identify Biological and Imaging markerS of CardiovascUlar Outcomes in Stroke) includes large-vessel-occlusion (LVO) AIS treated with mechanical thrombectomy (MT) following brain magnetic resonance imaging (MRI) including both CE-MRA and TOF-MRA. Locations of arterial occlusions were assessed independently for both MRA techniques and compared to brain DSA findings. Number of patients needed was 48 patients to exclude a difference of more than 20%. Discrepancy factors were assessed using univariate general linear models analysis. RESULTS: The study included 151 patients with a mean age of 67.6±15.9years. In all included patients, TOF-MRA and CE-MRA detected arterial occlusions, which were confirmed by brain DSA. For CE-MRA, 38 (25.17%) patients had discordant findings compared with brain DSA and 50 patients (33.11%) with TOF-MRA. The discordance factors were identical for both MRA techniques namely, tandem occlusions (OR=1.29, P=0.004 for CE-MRA and OR=1.61, P<0.001 for TOF-MRA), proximal internal carotid artery occlusions (OR=1.30, P=0.002 for CE-MRA and OR=1.47, P<0.001 for TOF-MRA) and time from MRI to MT (OR=1.01, P=0.01 for CE-MRA and OR=1.01, P=0.02 for TOF-MRA). CONCLUSION: Both MRA techniques are inferior to brain DSA in localizing arterial occlusions in LVO-AIS patients despite addressing the migratory nature of the thrombus.


Assuntos
Arteriopatias Oclusivas , AVC Isquêmico , Acidente Vascular Cerebral , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital/métodos , Encéfalo , Meios de Contraste , Humanos , Angiografia por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Trombectomia
3.
Rev Neurol (Paris) ; 176(3): 194-199, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31987628

RESUMO

PURPOSE: Intracranial plaque gadolinium enhancement revealed by high-resolution MRI imaging (HR MRI) is considered as a marker of plaque inflammation, a contributing factor of plaque unstability. The aim of the present study was to assess the distribution of gadolinium enhancement in intracranial atherosclerosis. METHODS: Single center analysis of ischemic stroke patients with intracranial atherosclerotic stenosis of M1 or M2 segments of middle cerebral artery, or terminal internal carotid artery (ICA) based on CT-angio or MR-angio. High-resolution MRI imaging (HRMRI) was performed within 6 first weeks following the index event, with 3DT2 BB (black-blood) and 3D T1 BB MR sequences pre and post-contrast administration. RESULTS: We identified 8 patients with 14 plaques, 4 were deemed non-culprit and 10 culprit. All culprit plaques (10/10 plaques) and 3 out of 4 non-culprit plaques showed a gadolinium enhancement. CONCLUSION: At the acute/subacute stage of stroke, a gadolinium enhancement may affect multiple asymptomatic intracranial plaques and may reflect a global inflammatory state.


Assuntos
Artérias/diagnóstico por imagem , Aumento da Imagem/métodos , AVC Isquêmico/diagnóstico por imagem , Angiografia por Ressonância Magnética/métodos , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Artérias/metabolismo , Artérias/patologia , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Artéria Carótida Interna/diagnóstico por imagem , Artéria Carótida Interna/metabolismo , Artéria Carótida Interna/patologia , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/metabolismo , Estenose das Carótidas/patologia , Meios de Contraste/farmacocinética , Feminino , Gadolínio/farmacocinética , Humanos , Arteriosclerose Intracraniana/diagnóstico por imagem , Arteriosclerose Intracraniana/metabolismo , AVC Isquêmico/metabolismo , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/metabolismo , Artéria Cerebral Média/patologia , Placa Aterosclerótica/diagnóstico por imagem , Placa Aterosclerótica/metabolismo , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/metabolismo , Síndrome de Resposta Inflamatória Sistêmica/metabolismo
4.
Rev Neurol (Paris) ; 175(9): 534-543, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31208813

RESUMO

INTRODUCTION: Currently, no single diagnostic modality allows the distinction between early progression (EP) and pseudo-progression (Psp) in glioblastoma patients. Herein we aimed to identify the characteristics associated with EP and Psp, and to analyze their diagnostic value alone and in combination. MATERIAL AND METHODS: We reviewed the clinical, conventional magnetic resonance imaging (MRI), and molecular characteristics (MGMT promoter methylation, IDH mutation, and EGFR amplification) of glioblastoma patients who presented an EP (n=59) or a Psp (n=24) within six months after temozolomide radiochemotherapy. We analyzed relative cerebral blood volume (rCBV) and relative vessel permeability on K2 maps (rK2) in a subset of 33 patients using dynamic-susceptibility-contrast MRI. RESULTS: In univariate analysis, EP was associated with neurological deterioration, higher doses of dexamethasone, appearance of a new enhanced lesion, subependymal enhancement, higher rCBV and rK2 values. Psp occurred earlier after radiotherapy completion and was associated with IDH1 R132H mutation, and MGMT methylation. In multivariate analysis, rCBV, rK2, and MGMT methylation status were independently associated with EP and Psp. All patients with a methylated MGMT promoter and a low rCBV (<1.75) were classified as Psp while all patients with an unmethylated MGMT promoter and a high rCBV (≥1.75) were classified as EP. Among patients with discordant MGMT methylation and rCBV characteristics, higher rK2 values tended to be associated with EP. CONCLUSION: Combined analysis of MGMT methylation, rCBV and vessel permeability on K2 maps seems helpful to distinguish EP from Psp. A prospective study is warranted to confirm these results.


Assuntos
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/terapia , Metilação de DNA , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioblastoma/diagnóstico , Glioblastoma/terapia , Imageamento por Ressonância Magnética/métodos , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Quimiorradioterapia/efeitos adversos , Meios de Contraste , Metilases de Modificação do DNA/análise , Enzimas Reparadoras do DNA/análise , Diagnóstico Diferencial , Progressão da Doença , Feminino , Seguimentos , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Lesões por Radiação/diagnóstico , Lesões por Radiação/genética , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Proteínas Supressoras de Tumor/análise
5.
Neurochirurgie ; 64(2): 117-123, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29705020

RESUMO

Almost all primary hemifacial spasms are associated with one or more neurovascular conflicts, most often at the root exit zone in the immediate vicinity of the brainstem. Imaging has first to exclude a secondary hemifacial spasm and secondly to search for and characterize the responsible neurovascular conflict(s). Magnetic resonance imaging should include high-resolution anatomical hyper T2-weighted sequences and magnetic resonance angiography by using 1.5 or even better 3 Tesla magnets. The most frequent vascular compressions are from the anterior-inferior cerebellar artery, the posterior-inferior cerebellar artery and the vertebrobasilar artery; venous conflicts are very rare. Conflicts are often multiple; also, the same vessel may compress the facial nerve in two places. Also, conflicts may be aided by particular anatomical circumstances, including arterial dolichoectasia, posterior fossa with a small volume or bony malformations.


Assuntos
Nervo Facial/cirurgia , Espasmo Hemifacial/patologia , Espasmo Hemifacial/cirurgia , Artéria Vertebral/cirurgia , Tronco Encefálico/irrigação sanguínea , Tronco Encefálico/cirurgia , Humanos , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Artéria Vertebral/patologia
7.
Neurochirurgie ; 61(2-3): 113-22, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25676911

RESUMO

Pineal tumors are rare and include a large variety of entities. Germ cell tumors are relatively frequent and often secreting lesions. Pineal parenchymal tumors include pineocytomas, pineal parenchymal tumor of intermediate differentiation, pineoblastomas and papillary tumors of the pineal region. Other lesions including astrocytomas and meningiomas as well as congenital malformations i.e. benign cysts, lipomas, epidermoid and dermoid cysts, which can also arise from the pineal region. Imagery is often non-specific but detailed analysis of the images compared with the hormone profile can narrow the spectrum of possible diagnosis.


Assuntos
Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Neoplasias Embrionárias de Células Germinativas/patologia , Glândula Pineal/patologia , Pinealoma/patologia , Astrocitoma/diagnóstico , Neoplasias Encefálicas/diagnóstico , Humanos , Meningioma/diagnóstico , Meningioma/patologia , Pinealoma/diagnóstico
8.
Neurochirurgie ; 61(2-3): 193-200, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25441707

RESUMO

INTRODUCTION: Exophytic tectal plate tumours are a particular kind of brain stem tumour that can be treated with microsurgical resection. This paper reports our surgical experience with a paediatric series stressing and underlines the fact that this surgery can be possible because the rate of surgical mortality is low in experienced hands with acceptable morbidity. MATERIAL AND METHODS: From 1997 to 2010, 27 patients were treated for exophytic tectal plate tumours. The clinical symptomatology was characterized by an intracranial hypertensive syndrome in 77% of cases, visual disorders in 36% of cases and a Parinaud's syndrome in 12% of cases. All patients were studied using a pre-operative cranio-spinal MRI with and without gadolinium. Hydrocephalus was present in 20 cases treated with a VP shunt in 6 cases and an ETV in the other cases. The surgical removal was total in 60% of cases, partial in 28% of cases and only a large biopsy in 12% of cases. From an histological point of view benign gliomas were diagnosed in 84% of cases and in 16% of cases were classified as WHO grade II and III. Eight patients needed complementary treatment, four with chemotherapy and four with chemotherapy associated to radiotherapy. As a surgical complication two patients had hydrocephalus, one patient had a sub-dural acute haematoma, two patients had an infectious complication requiring surgical treatment and antibiotic therapy, and 5 patients a mechanical shunt dysfunction. No post-surgical mortality was observed. RESULTS: The most recent results after a median survival of 4.3 years show that 22 patients are still alive while 5 patients died of a progressive disease. Twenty patients in school age continue to follow a normal school programme but 10 patients need assistance. CONCLUSION: Exophytic tectal plate tumours can be treated based on a microsurgical approach in paediatric patients. In experienced hands surgery can be performed with an acceptable morbidity and with zero percent mortality. In our experience, the sub-occipital transtentorial approach permits a wide view of the region and safe surgical removal.


Assuntos
Neoplasias do Tronco Encefálico/patologia , Neoplasias do Tronco Encefálico/cirurgia , Glioma/patologia , Glioma/cirurgia , Hidrocefalia/patologia , Hidrocefalia/cirurgia , Adolescente , Idoso , Biópsia/métodos , Neoplasias do Tronco Encefálico/diagnóstico , Criança , Feminino , Glioma/diagnóstico , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Resultado do Tratamento , Ventriculostomia/métodos
10.
Case Rep Transplant ; 2013: 708961, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24363951

RESUMO

Posterior reversible encephalopathy syndrome is a well-known complication of treatment by tacrolimus. We report 2 cases of lung transplant recipients treated with tacrolimus who developed cerebral microbleeds on T2∗-weighted sequences in the acute setting of posterior reversible encephalopathy syndrome. Cerebral microbleeds may be a marker of tacrolimus-induced vasculopathy that may be detected earlier by neuropsychological and magnetic resonance imaging monitoring in transplant recipients treated with tacrolimus.

11.
Neurol Sci ; 32 Suppl 3: S325-30, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21932092

RESUMO

The Chiari I malformation represents a complex disease and its pathophysiology is not completely understood and consequently different surgical procedures have been proposed in the literature. The use of MRI have increased the diagnosis of Chiari I malformation but generally the Chiari I is characterized by the herniation of tonsils at 5 mm below the plane of the occipital hole. The consequent disturbance of the CSF circulation at the level of the cranio-vertebral junction favors the occurrence of the syrinx between 20 and 70% of cases in pediatric series. Different surgical techniques have been proposed. We report two series of patients treated with the same surgical procedure except for the use of a Goretex dural patch in the second group with better clinical results. Our experience seems to confirm that the Chiari I malformation is a complex disease in which the impairment of the CSF circulation plays an important role to explain the severity of the clinical picture. The bone decompression and the restauration of the CSF circulation with a dural patch with Goretex seems to be effective for improving the clinical picture with good results.


Assuntos
Malformação de Arnold-Chiari/diagnóstico , Malformação de Arnold-Chiari/cirurgia , Descompressão Cirúrgica/métodos , Laminectomia/métodos , Imageamento por Ressonância Magnética , Adolescente , Malformação de Arnold-Chiari/complicações , Criança , Pré-Escolar , França , Humanos , Lactente , Estudos Retrospectivos , Siringomielia/diagnóstico , Siringomielia/etiologia , Siringomielia/cirurgia , Resultado do Tratamento
12.
Rev Neurol (Paris) ; 167(8-9): 626-31, 2011.
Artigo em Francês | MEDLINE | ID: mdl-21481904

RESUMO

INTRODUCTION: Idiopathic vasospastic angiopathy of the internal carotid arteries is a rare and largely unknown cause of ischemic stroke. METHODS: We report the case of a 39-year-old man with migraine treated by beta-blockers, who had been suffering from progressive right visual impairment and headache for one week. He then experienced a seizure and left hemiparesis. Ophthalmological examination revealed right retinal ischemia and partial left homonymous hemianopia. MRI revealed a long stenosis of both carotid arteries and a recent ischemic stroke in the territory of the right middle cerebral artery. The diagnosis of vasospastic angiopathy of the internal carotid arteries was made based on a second MRI and colored duplex sonography which showed a decrease in the stenosis and no intraparietal hematoma confirming the vasospasm mechanism for stenosis. The clinical course was favorable with calcium channel blockers and aspirin. Use of vasoconstrictor treatments was contraindicated. DISCUSSION/CONCLUSION: Idiopathic vasospastic angiopathy of the internal carotid arteries has been rarely documented. Association with migraine has been mentioned but remains unclear in the literature. This etiology for stroke is probably under-diagnosed due to lack of rapid and repeated examinations of the cervical arteries (angio-MR and colored duplex sonography) to confirm the vasospasm mechanism. Recurrences have been reported justifying a specific secondary preventive treatment to induce vasodilatation. Vasoconstrictor treatments should be contraindicated.


Assuntos
Isquemia Encefálica/complicações , Estenose das Carótidas/complicações , Acidente Vascular Cerebral/etiologia , Vasoespasmo Intracraniano/complicações , Adulto , Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Estenose das Carótidas/tratamento farmacológico , Angiografia Cerebral , Hemianopsia/etiologia , Humanos , Isquemia/etiologia , Angiografia por Ressonância Magnética , Imageamento por Ressonância Magnética , Masculino , Transtornos de Enxaqueca/etiologia , Paresia/etiologia , Doenças Retinianas/etiologia , Convulsões/etiologia , Acidente Vascular Cerebral/tratamento farmacológico , Ultrassonografia Doppler Dupla , Vasoespasmo Intracraniano/tratamento farmacológico
14.
J Neurol Neurosurg Psychiatry ; 80(10): 1159-61, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19762907

RESUMO

Primary angiitis of the central nervous system (PACNS) is a rare inflammatory disease restricted to the CNS of unknown cause. Clinical presentation and evolution are highly variable with potentially fluctuating signs and symptoms. Brain imaging often shows supratentorial ischaemic lesions. Definite diagnosis is established by brain biopsy. Treatment usually combines glucocorticosteroids and cyclophosphamide. A case of PACNS is reported here, which was proved by a brain biopsy and characterised by unusually prominent involvement of the posterior cerebral fossa. Successful treatment with mycophenolate mofetil in combination with steroids is described.


Assuntos
Imunossupressores/uso terapêutico , Ácido Micofenólico/análogos & derivados , Vasculite do Sistema Nervoso Central/tratamento farmacológico , Vasculite do Sistema Nervoso Central/patologia , Adulto , Glucocorticoides/uso terapêutico , Humanos , Masculino , Ácido Micofenólico/uso terapêutico
15.
Neurochirurgie ; 55(2): 162-73, 2009 Apr.
Artigo em Francês | MEDLINE | ID: mdl-19303113

RESUMO

Knowledge of the anatomy of the cranial nerves is mandatory for optimal radiological exploration and interpretation of the images in normal and pathological conditions. CT is the method of choice for the study of the skull base and its foramina. MRI explores the cranial nerves and their vascular relationships precisely. Because of their small size, it is essential to obtain images with high spatial resolution. The MRI sequences optimize contrast between nerves and surrounding structures (cerebrospinal fluid, fat, bone structures and vessels). This chapter discusses the radiological anatomy of the cranial nerves.


Assuntos
Nervos Cranianos/anatomia & histologia , Diagnóstico por Imagem/métodos , Nervos Cranianos/irrigação sanguínea , Nervos Cranianos/diagnóstico por imagem , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Fluxo Sanguíneo Regional/fisiologia , Tomografia Computadorizada por Raios X
16.
AJNR Am J Neuroradiol ; 30(1): 194-8, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18768716

RESUMO

BACKGROUND AND PURPOSE: The benefit of recanalization in basilar artery occlusion (BAO) has been established. The baseline extent of brain stem damage may also influence the outcome. We investigated whether a baseline diffusion-weighted imaging (DWI) score may provide additional prognostic value in BAO. MATERIALS AND METHODS: We analyzed baseline clinical and DWI parameters in consecutive patients treated with endovascular procedures for acute BAO. Brain stem DWI lesions were assessed by using a semiquantitative score based on arterial territory segmentation. Outcome at 3 months was dichotomized according to the modified Rankin Scale (mRS) as favorable (mRS, 0-2) or unfavorable (mRS, 3-6). Spearman rank correlation tests assessed the correlation between DWI and clinical variables. Univariate and multivariate logistic regression analyses were used to identify clinical and MR imaging predictors of outcome. RESULTS: Twenty-nine patients were included. The brain stem DWI score (median, 3; range, 0-14) was correlated with the baseline National Institutes of Health Stroke Scale (NIHSS) score and the presence and length of coma (r = 0.67, 0.49, and 0.53, respectively; P < .01). Recanalization was achieved in 76%. A higher baseline NIHSS score (P = .02) and brain stem DWI score (P = .03), a lower Glasgow Coma Scale score (P = .04), and the presence of coma (P = .05) were associated with poor outcome in univariate analysis. Multivariate analysis showed that the brain stem DWI score was the only independent baseline predictor for clinical outcome (P = .026). CONCLUSIONS: Baseline brain stem DWI lesion score is an independent marker of outcome in BAO.


Assuntos
Isquemia Encefálica/diagnóstico , Tronco Encefálico/irrigação sanguínea , Tronco Encefálico/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Avaliação de Resultados em Cuidados de Saúde/métodos , Insuficiência Vertebrobasilar/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Neuroimage ; 40(3): 1251-6, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18313943

RESUMO

To date, two positron emission tomography (PET) studies have explored 5-HT(1A) receptor density in the hippocampus of Alzheimer's disease (AD) patients. They showed early changes of 5-HT(1A) receptors in this brain region, known to have a dense serotonergic innervation. These studies only reported measurements in hippocampus. In the present PET study, we used an antagonist of 5-HT(1A) receptors, the [(18)F]MPPF (1) to explore 5-HT(1A) receptor density in the whole brain of AD patients at a mild stage of dementia and amnestic mild cognitive impairment (aMCI) patients compared to a control population; (2) to explore more precisely the 5-HT(1A) receptor density in the limbic brain regions of AD patients and aMCI patients compared to controls. Voxel-based analyses were performed to assess differences in the [(18)F]MPPF binding potential (BP) between AD patients and aMCI patients compared to controls. Analyses of whole-brain [(18)F]MPPF BP showed a global decrease in AD brains in contrast with a global increase in aMCI brains. In AD brains, a significant decrease of BP was detected in hippocampus and parahippocampal gyrus, whereas a significant increase of BP was observed in the inferior occipital gyrus in aMCI brains. These whole brain results are in accordance to hippocampal data reported in a previous study, showing an increase of [(18)F]MPPF binding in the aMCI group contrasting with a decrease in the AD group. Altogether, these results suggest the implication of a compensatory mechanism illustrated by an up regulation of serotonergic metabolism at the aMCI stage before a breakdown of this mechanism at the AD stage. This difference of serotonergic receptor labeling allows to distinguish the groups of aMCI patients from mild AD patients with specific [(18)F]MPPF PET profiles for each patient group.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Amnésia/diagnóstico por imagem , Transtornos Cognitivos/diagnóstico por imagem , Piperazinas , Piridinas , Idoso , Doença de Alzheimer/psicologia , Amnésia/psicologia , Encéfalo/diagnóstico por imagem , Transtornos Cognitivos/psicologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Processamento de Imagem Assistida por Computador , Sistema Límbico/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Receptor 5-HT1A de Serotonina/metabolismo
18.
Neurology ; 69(10): 1012-7, 2007 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-17785670

RESUMO

OBJECTIVE: Recent studies have suggested modifications of serotonin cerebral metabolism and of 5-HT(1A) receptors density in Alzheimer disease (AD). This study aims at exploring hippocampus 5-HT(1A) receptor density in patients at the amnesic mild cognitive impairment (aMCI) and mild AD dementia stages. METHODS: With use of PET with a selective 5-HT(1A) antagonist, 2'-methoxyphenyl-(N-2'-pyridinyl)-p-[(18)F]fluoro-benzamidoethylpiperazine ([(18)F]MPPF), the hippocampus 5-HT(1A) binding potential (BP) was quantified in 10 patients with mild AD, in 11 patients with aMCI, and in 21 aged paired control subjects. To take into account hippocampal atrophy, a partial volume correction was applied to the [(18)F]MPPF data, leading to the calculation of a corrected BP (BP(c)). Comparison of hippocampus BP over populations was performed using Kruskal-Wallis rank analysis. RESULTS: Hippocampus serotonergic receptor binding distinguishes patients from controls and patients with aMCI from patients with AD. In aMCI patients, the mean hippocampus BP(c) was 59% higher than the controls' (p < 0.005), and it was conversely 35% lower in patients with mild AD (p < 0.01). The difference in BP(c) values between patients with aMCI and mild AD was large, resulting in a p value of <0.0005. These differences were not related to hippocampus atrophy. CONCLUSION: A compensatory mechanism illustrated by an up-regulation of serotonergic metabolism has been shown at the stage of amnesic mild cognitive impairment (aMCI) in contrast with a dramatic decrease at later stages of Alzheimer disease (AD). This difference of hippocampus serotonergic receptor labeling allows distinguishing of patients with aMCI from those with mild AD. Exploring 5-HT(1A) receptors with 2'-methoxyphenyl-(N-2'-pyridinyl)-p-(18)F-fluoro-benzamidoethylpiperazine PET seems to be of interest for better understanding pathophysiologic changes at early stages of AD.


Assuntos
Transtornos Cognitivos/metabolismo , Hipocampo/metabolismo , Serotonina/metabolismo , Regulação para Cima/fisiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/psicologia , Biomarcadores/metabolismo , Transtornos Cognitivos/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons/métodos , Receptor 5-HT1A de Serotonina/biossíntese , Receptor 5-HT1A de Serotonina/metabolismo , Serotonina/biossíntese
19.
Rev Neurol (Paris) ; 163(1): 134-7, 2007 Jan.
Artigo em Francês | MEDLINE | ID: mdl-17304182

RESUMO

Cerebral amyloid angiopathy (CAA) is characterized by deposition of cerebrovascular amyloid protein in the media of leptomeningeal vessels. (amyloid B protein, cystatin C, transthyretin, gelsolin, and prion protein). It is a cause of cerebrovascular disorders including cerebral hemorrhage, cognitive impairment and unusually transient neurological symptoms. It is the main contributing factor to cerebral hemorrhage after hypertension in the elderly. We aimed to review epidemiological, pathophysiological and clinical and MRI imaging data in CAA.


Assuntos
Angiopatia Amiloide Cerebral , Angiopatia Amiloide Cerebral/diagnóstico , Angiopatia Amiloide Cerebral/fisiopatologia , Humanos
20.
Rev Neurol (Paris) ; 162(10): 1014-8, 2006 Oct.
Artigo em Francês | MEDLINE | ID: mdl-17028571

RESUMO

Acute cerebral angiopathy is a rare neuro-vascular complication in postpartum. In this setting, the implication of vasoconstrictive drugs used for lactation or deliverance hemorrhage inhibition has been established. This review aimed 1) to describe, epidemiologic, clinical and diagnostic features of this pathological condition. 2) To put in perspective this condition within the scope of neurovascular clinical syndrome of pregnancy.


Assuntos
Doenças Arteriais Cerebrais/diagnóstico , Transtornos Puerperais/diagnóstico , Doenças Arteriais Cerebrais/epidemiologia , Doenças Arteriais Cerebrais/parasitologia , Diagnóstico Diferencial , Feminino , Humanos , Gravidez , Complicações na Gravidez/diagnóstico , Resultado do Tratamento
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