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1.
AJNR Am J Neuroradiol ; 42(9): 1695-1701, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34244128

RESUMO

BACKGROUND AND PURPOSE: There is a paucity of data regarding the incidence of structural brain lesions in children with new-onset unprovoked seizures. Our aim was to determine the frequencies and types of epileptogenic lesions detected on a dedicated epilepsy protocol MR imaging according to age group, the presence of developmental delay, and the number and types of seizures. MATERIALS AND METHODS: Consecutive children between 6 months and 18 years of age with new-onset unprovoked seizures were included. The frequencies and types of epileptogenic lesions were determined and then stratified according to sex, age groups, the presence of developmental delay, and the number and types of seizures at presentation. Multivariate analysis was used to identify variables significantly associated with the presence of epileptogenic lesions. RESULTS: One thousand children were included. An epileptogenic lesion was identified in 26%, with malformations of cortical development being the most common lesion (32%), followed by hypoxic-ischemic injury (20%) and vascular etiologies (16%). Univariate analysis showed a significant increase in the frequency of epileptogenic lesions with decreasing age, the presence of developmental delay, and the number and types of seizures at presentation. The presence of developmental delay and seizure type at presentation remained significant in a multivariate analysis. CONCLUSIONS: We documented a relatively high rate of epileptogenic lesions in children with new-onset seizures, with the presence of developmental delay and specific seizure types being associated with a higher likelihood of detecting an epileptogenic lesion on neuroimaging. This study fulfills the requirements of the study design recommended by the Practice Committee of the American Academy of Neurology, and we hope that our results will assist the relevant societies and committees in formulating neuroimaging guidelines for children with new-onset seizures.


Assuntos
Imageamento por Ressonância Magnética , Neuroimagem , Adolescente , Encéfalo/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Convulsões/diagnóstico por imagem , Convulsões/epidemiologia
2.
Clin Radiol ; 74(11): 898.e15-898.e23, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31474303

RESUMO

AIM: To highlight magnetic resonance imaging (MRI) and computed tomography (CT) characteristics in distinguishing benign from high-grade meningiomas (World Health Organization [WHO] grade II and III) preoperatively. MATERIALS AND METHODS: Seventy-one patient who underwent surgical resection of intracranial meningiomas at American University of Beirut Medical Center between 2008 and 2017 were evaluated for various CT and MRI features. The correlation between imaging findings, histopathological grading, and operative reports was analysed via univariate and multivariate logistic regression analysis. MRI specificity and sensitivity in detecting meningioma brain invasion as compared to operative reports post-resection was detected. RESULTS: Univariate analysis results showed a significant correlation between high-grade meningiomas and several MRI features including tumour size and volume (p=0.002,0.02), heterogeneous enhancement (p<0.0001), presence of intra-tumoural necrosis (p<0.0001), ill-defined margin (p=0.003), bone erosion (p=0.004), brain invasion (p=0.001), and a higher rate of recurrence (p=0.007) Only brain invasion and presence of intra-tumoural necrosis were significantly correlated with the high-grade meningioma in multivariate analysis. Hyperostosis of the adjacent skull was the only significant CT feature predicting the presence of low-grade meningioma. MRI showed 79% specificity and 20% sensitivity, 92% negative predictive value and 7% positive predictive value in detecting meningioma brain invasion. CONCLUSION: MRI has a promising role in predicting meningioma grade prior to resection, which can directly impact patients' management protocols regarding surgical planning and complications.


Assuntos
Neoplasias Meníngeas/patologia , Meningioma/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Carga Tumoral
4.
Ann Burns Fire Disasters ; 31(4): 278-291, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30983928

RESUMO

The skin is a natural barrier between the interior milieu of the organism and its environment. This barrier has multiple physiological functions and may be affected by an array of pathologies including wounds and burns. The present study aims to determine the effect of the nervous system on wound healing. Specifically, this study tested the effect of denervation by chemical ablation on the burn wound healing process using guanethidine for denervation of the sympathetic postganglionic neurons and resiniferatoxin for denervation of the sensory capsaicin-sensitive fibres. Animals were divided into 8 different groups: (1) control group, (2) sensory denervated and burned, (3) sensory denervated non-burned, (4) sympathetic denervated and burned, (5) sympathetic denervated non-burned, (6) vehicle sensory burned, (7) vehicle sympathetic burned, (8) non-denervated burned. We measured different morphologic and biochemical parameters such as wound surface area, histological alterations and mast cells. In addition, NGF, IL-1ß, IL-6 and IL-8 levels were determined using the ELISA technique. The gross observations, the histological data including mast cell modulation, as well as the molecular data, speak in favour of a significant delay in burn wound healing caused by sensory denervation. On the other hand, results support the positive role of sympathetic denervation in speeding up the healing process. The dual effect of the nervous system on burn wound healing is being documented in an animal model for the first time.


La peau est une barrière naturelle entre le milieu intérieur et son environnement. Elle a des fonctions physiologiques multiples et peut être atteinte par de nombreuses pathologies parmi lesquelles plaies et brûlures. Cette étude a pour but d'évaluer les effets du système nerveux sur la cicatrisation et plus particulièrement ceux de la dénervation chimique par guanéthidine des neurones sympathiques post ganglionnaires ainsi que celle des fibres sensitives à capsaïcine par résiniferatoxine. Des animaux ont été répartis en 8 groupes : (1) contrôle, (2) dénervation sensitive + brûlure, (3) dénervation sensitive sans brûlure, (4) dénervation sympathique + brûlure, (5) dénervation sympathique sans brûlure, (6) solvant de résiniferatoxine + brûlure, (7) solvant de guanéthidine + brûlure, (8) pas de dénervation + brûlure. Nous avons mesuré plusieurs paramètres morphologiques et biochimiques parmi lesquels la surface brûlées, les anomalies histologiques et la fonction mastocytaire. NGF, IL1b, IL6 et IL8 ont été mesurés par méthode ELISA. L'observation clinique, les données histologiques dont la modulation mastocytaire ainsi que les données moléculaires orientent vers un ralentissement de la cicatrisation après dénervation sensitive alors que la dénervation sympathique l'accélère. C'est la première fois que ces effets opposés des dénervations sélective est observée chez l'animal.

5.
AJNR Am J Neuroradiol ; 39(2): 369-374, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29217740

RESUMO

BACKGROUND AND PURPOSE: Few articles in the literature have looked at the diameter of the optic nerve on MR imaging, especially in children, in whom observations are subjective and no normative data exist. The aim of this study was to establish a data base for optic nerve diameter measurements on MR imaging in the pediatric population. MATERIALS AND METHODS: This was a retrospective study on the MR imaging of pediatric subjects (younger than 18 years of age) at the Department of Diagnostic Radiology at the American University of Beirut Medical Center, Beirut, Lebanon. The optic nerve measurements were obtained by 3 raters on axial and coronal sections at 3 mm (retrobulbar) and 7 mm (intraorbital) posterior to the lamina cribrosa. RESULTS: Of 211 scans of patients (422 optic nerves), 377 optic nerves were measured and included. Ninety-four patients were female (45%) and the median age at MR imaging was 8.6 years (interquartile range, 3.9-13.3 years). Optic nerves were divided into 5 age groups: 0-6 months (n = 18), 6 months-2 years (n = 44), 2-6 years (n = 86), 6-12 years (n = 120), and 12-18 years (n = 109). An increase in optic nerve diameter was observed with age, especially in the first 2 years of life. Measurements did not differ with eye laterality or sex. CONCLUSIONS: We report normative values of optic nerve diameter measured on MR imaging in children from birth to 18 years of age. A rapid increase in optic nerve diameter was demonstrated during the first 2 years of life, followed by a slower increase. This was independent of sex or eye laterality.


Assuntos
Nervo Óptico/anatomia & histologia , Nervo Óptico/crescimento & desenvolvimento , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética/métodos , Masculino , Valores de Referência , Estudos Retrospectivos
7.
J Thromb Haemost ; 8(1): 54-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19817994

RESUMO

BACKGROUND: A high incidence of thrombotic events in thalassemia intermedia (TI) patients led to the identification of a hypercoagulable state. Brain involvement has not been widely studied in TI, although limited reports confirm a low incidence of overt stroke and high incidence of silent brain infarcts. PATIENTS/METHODS: This was a prospective study conducted on 30 adult, splenectomized TI patients. Patients were screened for absence of neurological signs or symptoms, and stroke-related risk factors. Patient charts were reviewed for demographics, duration since splenectomy, and any history of transfusion therapy. Blood samples were obtained for complete blood counts and serum ferritin. Direct determination of liver iron concentration (LIC) was performed by R2 magnetic resonance imaging (MRI). Brain MRI was performed on all patients, looking for ischemic lesions and/or atrophy. RESULTS: The mean age of patients was 32.1 +/- 11 years (range, 18-54 years), with a male to female ratio of 13:17. Eighteen patients (60%) had evidence of one or more white matter lesions (WMLs) on brain MRI, all involving the subcortical white matter. Fourteen patients had evidence of multiple WMLs, with a mean of 5 +/- 10 lesions (range, 2 to > 40 lesions). The vast majority of patients (94%) had small (< 0.5 cm) to medium (0.5-1.5 cm) WMLs, with only one patient showing evidence of a large (> 1.5 cm) WML. Eleven patients (37%) had mild cerebral atrophy. On multivariate analysis only age and transfusion history were independently and significantly associated with the occurrence of zero, single or multiple WMLs. CONCLUSION: WMLs and brain atrophy are a common finding in adult, splenectomized, TI patients. Increasing age and transfusion naivety are associated with a higher incidence and multiplicity of lesions.


Assuntos
Isquemia Encefálica/etiologia , Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética , Esplenectomia , Talassemia/complicações , Talassemia/cirurgia , Adolescente , Adulto , Fatores Etários , Atrofia , Transfusão de Sangue , Isquemia Encefálica/epidemiologia , Isquemia Encefálica/patologia , Distribuição de Qui-Quadrado , Feminino , Humanos , Incidência , Líbano/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Talassemia/epidemiologia , Talassemia/patologia , Adulto Jovem
8.
AJNR Am J Neuroradiol ; 30(5): 936-40, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19193756

RESUMO

BACKGROUND AND PURPOSE: Hereditary spastic paraplegia (HSP) is a disorder characterized by degeneration of the corticospinal tracts and posterior column of the spinal cord. Previously described radiologic findings included nonspecific brain abnormalities such as brain atrophy and white matter lesions, as well as atrophy of the spinal cord. In our study, we aimed to better characterize brain and spine MR imaging findings in a series of patients with HSP. MATERIALS AND METHODS: Nine patients from 4 different Lebanese families with the autosomal recessive form of HSP were included in the study. All patients underwent brain and whole-spine MR imaging. We assessed the presence of white matter abnormalities mainly along the corticospinal tracts, brain atrophy, thinning of the corpus callosum, and the presence of spinal cord atrophy or abnormal signal intensity. RESULTS: Imaging revealed mild brain atrophy (44%), atrophy of the corpus callosum (55%), white matter lesions (67%), abnormal T2 high signal intensity in the posterior limb of the internal capsule (55%), and mild spinal cord atrophy (33%). CONCLUSIONS: The MR imaging findings of HSP are nonspecific and variable; however, the most prominent features include atrophy of the corpus callosum, T2 signal intensity in the posterior limb of the internal capsule, and spinal cord atrophy.


Assuntos
Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Paraplegia Espástica Hereditária/patologia , Medula Espinal/patologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
9.
Neuropediatrics ; 40(5): 249-51, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20221964

RESUMO

We herein describe a 16-year-old child with acute lymphoblastic leukemia and acute pancreatitis who developed Wernicke's encephalopathy secondary to prolonged total parenteral nutrition (TPN) that lacked vitamin B1 supplementation. The patient showed a direct and complete response to thiamine therapy. Diagnostic challenges are discussed and recommendations for prophylactic vitamin B1 supplementation in children with leukemia who are placed on TPN are made.


Assuntos
Nutrição Parenteral Total/efeitos adversos , Encefalopatia de Wernicke/etiologia , Adolescente , Humanos , Masculino , Pancreatite/complicações , Pancreatite/terapia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Tiamina/uso terapêutico
10.
Neuropediatrics ; 39(2): 131-3, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18671192

RESUMO

We present the case of an 11-year-old boy with humoral immunodeficiency on monthly intravenous immunoglobulins (IVIG) infusions, evaluated for recurrent, brief, neurological deficits secondary to cerebral sinus thrombosis without any identifiable hypercoagulability state. Etiologic possibilities for the thrombotic event are presented with special discussion of IVIG-related cerebral thrombosis. To the best of our knowledge, our patient represents the first reported case of Bruton's disease on IVIG therapy developing a cerebral ischemic event and the second reported case of cerebral sinus thrombosis associated with IVIG use for any disease. Potential concerns regarding the risk of cerebral thrombosis during IVIG therapy in this and other disorders are reviewed.


Assuntos
Imunoglobulinas Intravenosas/efeitos adversos , Síndromes de Imunodeficiência/tratamento farmacológico , Trombose dos Seios Intracranianos/induzido quimicamente , Criança , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Masculino , Flebografia/métodos , Trombose dos Seios Intracranianos/patologia , Tomografia Computadorizada por Raios X/métodos
11.
Neuropediatrics ; 39(1): 46-50, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18504683

RESUMO

L-asparaginase is a critical component in the treatment of acute lymphoblastic leukemia in children. It is known to cause coagulation abnormalities, thrombosis and hemorrhage in the central nervous system in addition to vasculitis and hypersensitivity reactions. The purpose of this article is to present the first case-series of posterior reversible encephalopathy syndrome (PRES) associated with L-asparaginase treatment. We report 3 cases of children with acute lymphoblastic leukemia who developed seizures and altered sensorium after L-asparaginase therapy. MRI showed increased T(2) signal intensity predominant in the posterior regions of the brain suggestive of PRES. Two of our patients developed septic shock and deteriorated whereas one patient improved and recovered completely.


Assuntos
Asparaginase/efeitos adversos , Síndrome da Leucoencefalopatia Posterior/induzido quimicamente , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Asparaginase/uso terapêutico , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Criança , Pré-Escolar , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Síndrome da Leucoencefalopatia Posterior/patologia , Convulsões/induzido quimicamente , Choque Séptico/induzido quimicamente
13.
AJNR Am J Neuroradiol ; 29(2): 366-72, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18055564

RESUMO

BACKGROUND AND PURPOSE: Noninvasive diagnosis of brain lesions is important for the correct choice of treatment. Our aims were to investigate whether 1) proton MR spectroscopic imaging ((1)H-MRSI) can aid in differentiating between tumors and nonneoplastic brain lesions, and 2) perfusion MR imaging can improve the classification. MATERIALS AND METHODS: We retrospectively examined 69 adults with untreated primary brain lesions (brain tumors, n = 36; benign lesions, n = 10; stroke, n = 4; demyelination, n = 10; and stable lesions not confirmed on pathologic examination, n = 9). MR imaging and (1)H-MRSI were performed at 1.5T before biopsy or treatment. Concentrations of N-acetylaspartate (NAA), creatine (Cr), and choline (Cho) in the lesion were expressed as metabolite ratios and were normalized to the contralateral hemisphere. Dynamic susceptibility contrast-enhanced perfusion MR imaging was performed in a subset of patients (n = 32); relative cerebral blood volume (rCBV) was evaluated. Discriminant function analysis was used to identify variables that can predict inclusion in the neoplastic or nonneoplastic lesion groups. Receiver operator characteristic (ROC) analysis was used to compare the discriminatory capability of (1)H-MRSI and perfusion MR imaging. RESULTS: The discriminant function analysis correctly classified 84.2% of original grouped cases (P < .0001), on the basis of NAA/Cho, Cho(norm), NAA(norm), and NAA/Cr ratios. MRSI and perfusion MR imaging had similar discriminatory capabilities in differentiating tumors from nonneoplastic lesions. With cutoff points of NAA/Cho < or =0.61 and rCBV > or =1.50 (corresponding to diagnosis of the tumors), a sensitivity of 72.2% and specificity of 91.7% in differentiating tumors from nonneoplastic lesions were achieved. CONCLUSION: These results suggest a promising role for (1)H-MRSI and perfusion MR imaging in the distinction between brain tumors and nonneoplastic lesions in adults.


Assuntos
Neoplasias Encefálicas/diagnóstico , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Prótons , Adulto , Idoso , Encefalopatias/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
14.
Neuropediatrics ; 37(2): 110-3, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16773512

RESUMO

Kearns-Sayre syndrome (KSS) is a mitochondrial disorder consisting of external ophthalmoplegia, retinitis pigmentosa, ataxia and heart block. Magnetic resonance imaging (MRI) shows abnormal T2 high signal intensity in the deep gray matter nuclei, the cerebellar and the subcortical white matter. We report an unusual MR pattern of KSS, where the T2 images revealed radially oriented, hypointense stripes in hyperintense white matter, a characteristic MRI pattern of lysosomal disease not previously reported in KSS.


Assuntos
Encéfalo/patologia , Síndrome de Kearns-Sayre/patologia , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino
15.
J Neuroradiol ; 33(1): 62-6, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16528208

RESUMO

We report the case of a patient with NF-1 who presented with gross elephantiasis neuromatosa of her right leg. Prior to plastic surgery, Magnetic Resonance Imaging and Angiography (MRI and MRA) were performed to provide a detailed assessment of the extension as well as the vascular and muscular involvement of the neurofibroma.


Assuntos
Perna (Membro) , Neurofibroma Plexiforme/diagnóstico , Neurofibromatose 1/diagnóstico , Neoplasias de Tecidos Moles/diagnóstico , Adulto , Feminino , Humanos
16.
Ultrasound Obstet Gynecol ; 24(2): 180-5, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15287057

RESUMO

OBJECTIVE: To determine the accuracy of transvaginal sonography (TVS) for the diagnosis of deep pelvic endometriosis. METHODS: In a prospective study, 142 women with clinical signs of endometriosis underwent TVS followed by surgical and histopathological investigations. The presence and extent of endometriosis involving the uterosacral ligaments, vagina, rectovaginal septum, intestines, bladder and ovaries shown by TVS were compared with surgical and histological findings. The sensitivity, specificity, predictive values and accuracy of TVS for predicting deep pelvic endometriosis were assessed. RESULTS: Ovarian and deep pelvic endometriosis were found by surgery and histology in respectively 83 (58.5%) and 79 (55.6%) of the 142 patients. The sensitivity, specificity, and positive and negative predictive values of TVS for the diagnosis of deep pelvic endometriosis were 78.5%, 95.2%, 95.4% and 77.9%, respectively. The sensitivity and specificity of TVS for endometriotic involvement of the uterosacral ligaments, vagina, rectovaginal septum and intestines were 70.6% and 95.9%, 29.4% and 100%, 28.6% and 99.3%, and 87.2% and 96.8%, respectively. The sensitivity and specificity of TVS for bladder involvement were 71.4% and 100%, respectively. CONCLUSION: TVS accurately diagnoses intestinal and bladder endometriosis, but is less accurate for uterosacral, vaginal and rectovaginal septum involvement.


Assuntos
Endometriose/diagnóstico por imagem , Doenças dos Genitais Femininos/diagnóstico por imagem , Enteropatias/diagnóstico por imagem , Adulto , Idoso , Endometriose/patologia , Feminino , Doenças dos Genitais Femininos/patologia , Humanos , Enteropatias/patologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Sensibilidade e Especificidade , Ultrassonografia Doppler em Cores/métodos , Doenças da Bexiga Urinária/diagnóstico por imagem , Doenças da Bexiga Urinária/patologia
18.
Childs Nerv Syst ; 17(12): 754-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11862444

RESUMO

The authors report a case of intraspinal neurenteric cyst in a 22-month-old child, who presented with acute paraplegia following a vesicourethrogram. Despite 8 days' delay in surgical decompression, he made a complete neurological recovery. Neurenteric cysts are rare congenital lesions of the spinal canal lined with an epithelium of endodermal origin. They are usually located at the cervicothoracic junction and present with progressive mild to moderate signs of myelopathy. This is a unique case in regard both to its clinical presentation and to the excellent outcome after 8 days of complete paraplegia.


Assuntos
Defeitos do Tubo Neural/complicações , Paraplegia/complicações , Canal Medular/patologia , Vértebras Torácicas , Doença Aguda , Pré-Escolar , Descompressão Cirúrgica , Humanos , Imageamento por Ressonância Magnética , Masculino , Defeitos do Tubo Neural/cirurgia , Compressão da Medula Espinal/etiologia , Compressão da Medula Espinal/cirurgia
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