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1.
J Magn Reson Imaging ; 58(6): 1875-1881, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37052820

RESUMO

BACKGROUND: Papilledema is thought to be the hallmark sign of increased intracranial pressure (ICP). Distension of the subarachnoid space within the optic nerve sheath is also commonly reported in MR studies as an indirect sign of increased ICP. HYPOTHESIS: General anesthesia and positive pressure ventilation might result in changes in optic sheath diameter (OSD) observed on clinical brain MRI. STUDY TYPE: Retrospective. POPULATION: One hundred forty-five  patients (154 MRI scans, 7.3 years ± 5.1); 97 studies in the anesthesia group (4.4 years ± 3.4) of which 22 had papilledema, and 57 in the non-anesthesia group (12.3 years ± 3.2), of which 28 had papilledema. FIELD STRENGTH/SEQUENCE: 1.5T or 3.0T volumetric T2 images. T2 images were obtained from different vendors. ASSESSMENT: OSD, optic nerve diameter (OND), and peri-optic cerebrospinal fluid (CSF) were measured manually on T2-weighted MR images for various population subgroups (with and without anesthesia; with or without papilledema). The correlation between these measurements and the clinical diagnosis of papilledema was evaluated via receiver operating characteristic (ROC) analysis. STATISTICAL TESTS: Chi-square test; Mann-Whitney Test; Spearman's test and ROCs; Interclass correlation coefficient, P = 0.05. RESULTS: General anesthesia resulted in significantly larger mean OSD in patients with or without papilledema (7.3 ± 1.0 mm vs. 6.1 ± 1.1 mm and 6.7 ± 1.0 mm vs. 5.4 ± 0.9 mm, respectively). In the non-anesthesia group, the average OSD values (6.1 ± 1.1 mm) were significantly higher in papilledema patients compared to non-papilledema patients (5.4 ± 0.9 mm), with larger peri-optic CSF rim (1.6 ± 0.4 mm vs. 1.3 ± 0.3 mm). In the anesthesia group, OND was significantly larger in papilledema patients (3.4 ± 0.4 mm vs. 3.1 ± 0.5 mm), though the average peri-optic CSF rim did not reach a significance in papilledema compared with non-papilledema patients (2.0 ± 0.3 mm vs. 1.8 ± 0.4 mm, P = 0.06). In patients with general anesthesia, peri-optic CSF rim had a limited correlation with increased ICP. DATA CONCLUSION: In the pediatric population, imaging findings of increased OSD on brain MRI might be related to general anesthesia rather than increased ICP. The interpretation of optic nerve sheath distention should be reported cautiously in conjunction with anesthesia status, especially in the pediatric population. EVIDENCE LEVEL: 4 Technical Efficacy: 5.


Assuntos
Hipertensão Intracraniana , Papiledema , Humanos , Criança , Papiledema/diagnóstico , Estudos Retrospectivos , Nervo Óptico/diagnóstico por imagem , Anestesia Geral
2.
J Magn Reson Imaging ; 58(2): 642-649, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36495014

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) diagnosis is usually performed by analyzing contrast-weighted images, where pathology is detected once it reached a certain visual threshold. Computer-aided diagnosis (CAD) has been proposed as a way for achieving higher sensitivity to early pathology. PURPOSE: To compare conventional (i.e., visual) MRI assessment of artificially generated multiple sclerosis (MS) lesions in the brain's white matter to CAD based on a deep neural network. STUDY TYPE: Prospective. POPULATION: A total of 25 neuroradiologists (15 males, age 39 ± 9, 9 ± 9.8 years of experience) independently assessed all synthetic lesions. FIELD STRENGTH/SEQUENCE: A 3.0 T, T2 -weighted multi-echo spin-echo (MESE) sequence. ASSESSMENT: MS lesions of varying severity levels were artificially generated in healthy volunteer MRI scans by manipulating T2 values. Radiologists and a neural network were tasked with detecting these lesions in a series of 48 MR images. Sixteen images presented healthy anatomy and the rest contained a single lesion at eight increasing severity levels (6%, 9%, 12%, 15%, 18%, 21%, 25%, and 30% elevation in T2 ). True positive (TP) rates, false positive (FP) rates, and odds ratios (ORs) were compared between radiological diagnosis and CAD across the range lesion severity levels. STATISTICAL TESTS: Diagnostic performance of the two approaches was compared using z-tests on TP rates, FP rates, and the logarithm of ORs across severity levels. A P-value <0.05 was considered statistically significant. RESULTS: ORs of identifying pathology were significantly higher for CAD vis-à-vis visual inspection for all lesions' severity levels. For a 6% change in T2 value (lowest severity), radiologists' TP and FP rates were not significantly different (P = 0.12), while the corresponding CAD results remained statistically significant. DATA CONCLUSION: CAD is capable of detecting the presence or absence of more subtle lesions with greater precision than the representative group of 25 radiologists chosen in this study. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 3.


Assuntos
Imageamento por Ressonância Magnética , Esclerose Múltipla , Masculino , Humanos , Estudos Prospectivos , Sensibilidade e Especificidade , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Computadores , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Estudos Retrospectivos
3.
Pediatr Blood Cancer ; 70(12): e30689, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37740614

RESUMO

Retinal vein occlusion (RVO) and superior ophthalmic vein thrombosis (SOVT) are rare diseases in the pediatric population; however, the ophthalmic and neurologic morbidity are significant. As published data are scarce for these conditions, we present our experience with pediatric ocular venous thrombosis in four patients, and discuss recommended management for evaluation and treatment. We suggest performing thrombophilia workup for all pediatric patients with RVO or SOVT. In patients with thrombophilia risk factors or patients with additional thrombi, we highly recommend initiating anticoagulation therapy. There is a need for more research in order to determine the optimal management strategy.

4.
Neuroradiology ; 65(10): 1517-1525, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37436475

RESUMO

PURPOSE: Abnormal fetal brain measurements might affect clinical management and parental counseling. The effect of between-field-strength differences was not evaluated in quantitative fetal brain imaging until now. Our study aimed to compare fetal brain biometry measurements in 3.0 T with 1.5 T scanners. METHODS: A retrospective cohort of 1150 low-risk fetuses scanned between 2012 and 2021, with apparently normal brain anatomy, were retrospectively evaluated for biometric measurements. The cohort included 1.5 T (442 fetuses) and 3.0 T scans (708 fetuses) of populations with comparable characteristics in the same tertiary medical center. Manually measured biometry included bi-parietal, fronto-occipital and trans-cerebellar diameters, length of the corpus-callosum, vermis height, and width. Measurements were then converted to centiles based on previously reported biometric reference charts. The 1.5 T centiles were compared with the 3.0 T centiles. RESULTS: No significant differences between centiles of bi-parietal diameter, trans-cerebellar diameter, or length of the corpus callosum between 1.5 T and 3.0 T scanners were found. Small absolute differences were found in the vermis height, with higher centiles in the 3.0 T, compared to the 1.5 T scanner (54.6th-centile, vs. 39.0th-centile, p < 0.001); less significant differences were found in vermis width centiles (46.9th-centile vs. 37.5th-centile, p = 0.03). Fronto-occipital diameter was higher in 1.5 T than in the 3.0 T scanner (66.0th-centile vs. 61.8th-centile, p = 0.02). CONCLUSIONS: The increasing use of 3.0 T MRI for fetal imaging poses a potential bias when using 1.5 T-based charts. We elucidate those biometric measurements are comparable, with relatively small between-field-strength differences, when using manual biometric measurements. Small inter-magnet differences can be related to higher spatial resolution with 3 T scanners and may be substantial when evaluating small brain structures, such as the vermis.


Assuntos
Imageamento por Ressonância Magnética , Imãs , Feminino , Humanos , Estudos Retrospectivos , Estudos de Coortes , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/anatomia & histologia , Biometria/métodos
5.
Neuroradiology ; 64(6): 1249-1254, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34820712

RESUMO

PURPOSE: Apparent diffusion coefficient (ADC) values in the developing fetus provide valuable information on the diagnosis and prognosis of prenatal brain pathologies. Normative ADC data has been previously established in 1.5 T MR scanners but lacking in 3.0 T scanners. Our objective was to measure ADC values in various brain areas in a cohort of normal singleton fetuses scanned in a 3.0 T MR scanner. METHODS: DWI (diffusion-weighted imaging) was performed in 47 singleton fetuses with normal or questionably abnormal results on sonography followed by normal structural MR imaging. ADC values were measured in cerebral lobes (frontal, parietal, temporal lobes), basal ganglia, and pons. Regression analysis was used to examine gestational age-related changes in regional ADC. RESULTS: Median gestational age was 30.1 weeks (range, 26-34 weeks). There was a significant effect of region on ADC values, whereby ADC values were highest in cerebral lobes (parietal > frontal > temporal lobes), compared with basal ganglia. The lowest values were found in the pons. On regression analysis, there was a decrease in ADC values in basal ganglia and pons with increasing gestational age. ADC values in frontal, parietal, and temporal lobes were stable in our cohort. CONCLUSION: Regional brain ADC values in 3.0 T scanners are comparable with previously reported values in 1.5 T scanners, with similar changes over gestational age. Using 3.0 T scanners is increasing worldwide. For fetal imaging, establishing normal ADC values is critical as DWI enables a sensitive and quantitative technique to evaluate normal and abnormal brain development.


Assuntos
Imagem de Difusão por Ressonância Magnética , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Lactente , Gravidez , Terceiro Trimestre da Gravidez , Diagnóstico Pré-Natal/métodos
6.
Neuroradiology ; 64(3): 611-620, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34532765

RESUMO

PURPOSE: Tuberous sclerosis complex (TSC) is a genetic disorder characterized by multiorgan hamartomas, including cerebral lesions, with seizures as a common presentation. Most TSC patients will also experience neurocognitive comorbidities. Our objective was to use machine learning techniques incorporating clinical and imaging data to predict the occurrence of major neurocognitive disorders and seizures in TSC patients. METHODS: A cohort of TSC patients were enrolled in this retrospective study. Clinical data included genetic, demographic, and seizure characteristics. Imaging parameters included the number, characteristics, and location of cortical tubers and the presence of subependymal nodules, SEGAs, and cerebellar tubers. A random forest machine learning scheme was used to predict seizures and neurodevelopmental delay or intellectual developmental disability. Prediction ability was assessed by the area-under-the-curve of receiver-operating-characteristics (AUC-ROC) of ten-fold cross-validation training set and an independent validation set. RESULTS: The study population included 77 patients, 55% male (17.1 ± 11.7 years old). The model achieved AUC-ROC of 0.72 ± 0.1 and 0.68 in the training and internal validation datasets, respectively, for predicting neurocognitive comorbidity. Performance was limited in predicting seizures (AUC-ROC of 0.54 ± 0.19 and 0.71 in the training and internal validation datasets, respectively). The integration of seizure characteristics into the model improved the prediction of neurocognitive comorbidity with AUC-ROC of 0.84 ± 0.07 and 0.75 in the training and internal validation datasets, respectively. CONCLUSIONS: This proof of concept study shows that it is possible to achieve a reasonable prediction of major neurocognitive morbidity in TSC patients using structural brain imaging and machine learning techniques. These tools can help clinicians identify subgroups of TSC patients with an increased risk of developing neurocognitive comorbidities.


Assuntos
Esclerose Tuberosa , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Aprendizado de Máquina , Imageamento por Ressonância Magnética , Masculino , Transtornos Neurocognitivos/complicações , Estudos Retrospectivos , Convulsões/diagnóstico por imagem , Convulsões/etiologia , Esclerose Tuberosa/complicações , Esclerose Tuberosa/diagnóstico por imagem , Adulto Jovem
7.
Prenat Diagn ; 42(8): 978-984, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35726441

RESUMO

OBJECTIVES: To determine the rate of fetal and neonatal brain lesions and define risk factors for such lesions in pregnancies complicated by Twin Anemia Polycythemia Sequence (TAPS). METHODS: A retrospective cohort study of monochorionic twin pregnancies which were diagnosed with TAPS in a single tertiary medical center between 2013 and 2021. Pregnancies were followed with fetal brain neurosonogram every 2 weeks and fetal brain MRI (magnetic resonance imaging) was performed when indicated at 28-32 weeks of gestation; post-natal brain imaging included neonatal brain ultrasound. Pregnancies with pre- and post-natal brain lesions were compared to those without such findings. RESULTS: Overall, 23 monochorionic diamniotic pregnancies were diagnosed with TAPS over the study period resulting in perinatal survival of 91.3% (42/46). In 6/23 (26%) pregnancies and 7/46 (15.2%) fetuses pre- or post-natal brain lesions were detected, of whom five were the polycythemic twins and two were the anemic twins. Brain findings included intra-cerebral hemorrhage and ischemic lesions and were diagnosed prenatally in 6/7 (85.7%) cases. No risk factors for severe brain lesions were identified. CONCLUSIONS: TAPS may place the fetuses and neonates at increased risk for cerebral injuries. Incorporation of fetal brain imaging protocols may enhance precise prenatal diagnosis and allow for accurate parental counseling and post-natal care.


Assuntos
Anemia , Lesões Encefálicas , Transfusão Feto-Fetal , Policitemia , Anemia/complicações , Anemia/diagnóstico por imagem , Anemia/epidemiologia , Feminino , Transfusão Feto-Fetal/complicações , Transfusão Feto-Fetal/diagnóstico por imagem , Transfusão Feto-Fetal/epidemiologia , Feto , Humanos , Recém-Nascido , Policitemia/complicações , Policitemia/diagnóstico por imagem , Policitemia/epidemiologia , Gravidez , Gravidez de Gêmeos , Estudos Retrospectivos , Gêmeos Monozigóticos , Ultrassonografia Pré-Natal
8.
Am J Otolaryngol ; 43(1): 103237, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34560599

RESUMO

OBJECTIVE: Bone impaction (BI) is a common cause for emergency room visits. Among foreign bodies, fish bone is considered the most common. The sensitivity of symptoms in predicting BI is relatively low, making imaging a central tool to aid diagnosis. Current imaging practices include both neck plain film radiography and none-contrast CT scans of the neck. We evaluated the accuracy of neck plain film radiography and CT scans of the neck for the diagnosis of BI. METHODS: Retrospective review of all patients who presented to the emergency room between 2009 and 2016 with a suspicious history of BI whom underwent plain film neck radiography or CT. All Images were reviewed by two neuro-radiologist blinded to the clinical symptoms and findings. Symptoms, clinical findings and images results were compared to the final diagnosis. RESULTS: 89 patients (30.7%), out of 290 patients who presented with complaints of BI, were diagnosed with BI. Mean age was 44.7 years old. Plain film neck radiography failed to predict BI (sen. 14.4%, spe 89.8% accuracy 63.2%), neck CT has an improved accuracy and sensitivity in locating BI (sen. 83.3%, spe. 94.1% accuracy 92.5%). Interobserver agreement between the two neuro-radiologists was moderate (0.46) and substantial (0.77) in neck radiography and CT images, respectively. Neck radiography missed 60 (out of 61) oropharyngeal BI's. CONCLUSION: Neck radiography has high inter-observer variability and low sensitivity for the diagnosis of BI. Neck CT should be the first imaging modality in patients with suspicious complaints for BI and negative physical exam.


Assuntos
Corpos Estranhos/diagnóstico por imagem , Cervicalgia/diagnóstico por imagem , Pescoço/diagnóstico por imagem , Radiografia/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Adulto , Animais , Osso e Ossos/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Peixes , Corpos Estranhos/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Cervicalgia/etiologia , Variações Dependentes do Observador , Radiografia/métodos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos
9.
Isr Med Assoc J ; 23(10): 625-630, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34672443

RESUMO

BACKGROUND: Only a small proportion of schizophrenia patients present with catatonic symptoms. Imaging studies suggest that brain motor circuits are involved in the underlying pathology of catatonia. However, data about diffusivity dysregulation of these circuits in catatonic schizophrenia are scarce. OBJECTIVES: To assess the involvement of brain motor circuits in schizophrenia patients with catatonia. METHODS: Diffusion tensor imaging (DTI) was used to measure white matter signals in selected brain regions linked to motor circuits. Relevant DTI data of seven catatonic schizophrenia patients were compared to those of seven non-catatonic schizophrenia patients, matched for sex, age, and education level. RESULTS: Significantly elevated fractional anisotropy values were found in the splenium of the corpus callosum, the right peduncle of the cerebellum, and the right internal capsule of the schizophrenia patients with catatonia compared to those without catatonia. This finding showed altered diffusivity in selected motor-related brain areas. CONCLUSIONS: Catatonic schizophrenia is associated with dysregulation of the connectivity in specific motoric brain regions and corresponding circuits. Future DTI studies are needed to address the neural correlates of motor abnormalities in schizophrenia-related catatonia during the acute and remitted state of the illness to identify the specific pathophysiology of this disorder.


Assuntos
Imagem de Tensor de Difusão/métodos , Córtex Motor , Esquizofrenia Catatônica , Adulto , Anisotropia , Cerebelo/diagnóstico por imagem , Cerebelo/fisiopatologia , Conectoma/métodos , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/fisiopatologia , Correlação de Dados , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Cápsula Interna/diagnóstico por imagem , Cápsula Interna/fisiopatologia , Masculino , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiopatologia , Escalas de Graduação Psiquiátrica , Esquizofrenia Catatônica/diagnóstico , Esquizofrenia Catatônica/fisiopatologia
10.
Neuroradiology ; 61(7): 757-765, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30949746

RESUMO

PURPOSE: While MRI is the modality of choice for the assessment of patients with brain tumors, differentiation between various tumors based on their imaging characteristics might be challenging due to overlapping imaging features. The purpose of this study was to apply a machine learning scheme using basic and advanced MR sequences for distinguishing different types of brain tumors. METHODS: The study cohort included 141 patients (41 glioblastoma, 38 metastasis, 50 meningioma, and 12 primary central nervous system lymphoma). A computer-assisted classification scheme, combining morphologic MRI, perfusion MRI, and DTI metrics, was developed and used for tumor classification. The proposed multistep scheme consists of pre-processing, ROI definition, features extraction, feature selection, and classification. Feature subset selection was performed using support vector machines (SVMs). Classification performance was assessed by leave-one-out cross-validation. Given an ROI, the entire classification process was done automatically via computer and without any human intervention. RESULTS: A binary hierarchical classification tree was chosen. In the first step, selected features were chosen for distinguishing glioblastoma from the remaining three classes, followed by separation of meningioma from metastasis and PCNSL, and then to discriminate PCNSL from metastasis. The binary SVM classification accuracy, sensitivity and specificity for glioblastoma, metastasis, meningiomas, and primary central nervous system lymphoma were 95.7, 81.6, and 91.2%; 92.7, 95.1, and 93.6%; 97, 90.8, and 58.3%; and 91.5, 90, and 96.9%, respectively. CONCLUSION: A machine learning scheme using data from anatomical and advanced MRI sequences resulted in high-performance automatic tumor classification algorithm. Such a scheme can be integrated into clinical decision support systems to optimize tumor classification.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Aprendizado de Máquina , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/patologia , Diagnóstico Diferencial , Feminino , Glioblastoma/diagnóstico por imagem , Glioblastoma/patologia , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Linfoma/diagnóstico por imagem , Linfoma/patologia , Masculino , Meningioma/diagnóstico por imagem , Meningioma/patologia , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
11.
Fetal Diagn Ther ; 45(4): 268-274, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30121678

RESUMO

OBJECTIVES: Chiari II malformation is a congenital abnormality characterized by a small posterior fossa with downward displacement of the hindbrain into the foramen magnum. Diffusion-weighted imaging (DWI) can be used to quantitatively characterize brain injury and physiological maturation. We aim to evaluate DWI parameters of the infra- and supratentorial brain in fetuses with Chiari II malformation. METHODS: MRI and US studies of 26 fetuses with Chiari II malformation and 15 controls were evaluated for the presence/severity of hydrocephalus, myelomeningocele level, and brain apparent diffusion coefficient (ADC) values. Cerebral flow impedance parameters (resistance and pulsatile indexes, resistance index [RI], and pulsatility index [PI] respectively) from concurrently preformed fetal US were also evaluated. RESULTS: Of the Chiari II group, 16 fetuses had hydrocephalus. There was increasing severity of lateral ventriculomegaly in the high compared to low spinal dysraphism subgroups. There were significant lower ADC values in the frontal (p = 0.01) and temporal lobes (p = 0.05) in Chiari II group compared with normal, regardless of the presence or severity of hydrocephalus. Fetuses with Chiari II showed significantly lower RI and PI values. CONCLUSIONS: Abnormal ADC values indicate supratentorial microstructural changes in fetuses with Chiari II malformation. Further investigation of the role of diffusion imaging metrics in evaluating abnormal brain development, parenchymal damage and efficacy of fetal surgery is needed.


Assuntos
Malformação de Arnold-Chiari/diagnóstico por imagem , Cérebro/diagnóstico por imagem , Hidrocefalia/diagnóstico por imagem , Malformação de Arnold-Chiari/complicações , Malformação de Arnold-Chiari/fisiopatologia , Cérebro/embriologia , Desenvolvimento Fetal , Humanos , Hidrocefalia/complicações , Imageamento por Ressonância Magnética , Ultrassonografia Pré-Natal
12.
Neuroradiology ; 60(2): 137-150, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29279945

RESUMO

The current classification of malformations of cortical development is based on the type of disrupted embryological process (cell proliferation, migration, or cortical organization/post-migrational development) and the resulting morphological anomalous pattern of findings. An ideal classification would include knowledge of biological pathways. It has recently been demonstrated that alterations affecting the mechanistic target of rapamycin (mTOR) signaling pathway result in diverse abnormalities such as dysplastic megalencephaly, hemimegalencephaly, ganglioglioma, dysplastic cerebellar gangliocytoma, focal cortical dysplasia type IIb, and brain lesions associated with tuberous sclerosis. We review the neuroimaging findings in brain abnormalities related to alterations in the mTOR pathway, following the emerging trend from morphology towards genetics in the classification of malformations of cortical development. This approach improves the understanding of anomalous brain development and allows precise diagnosis and potentially targeted therapies that may regulate mTOR pathway function.


Assuntos
Imageamento por Ressonância Magnética/métodos , Malformações do Desenvolvimento Cortical/diagnóstico por imagem , Malformações do Desenvolvimento Cortical/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Neuroimagem/métodos , Humanos
14.
J Ultrasound Med ; 36(11): 2379-2386, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28649730

RESUMO

Sensitive, specific, and safe bedside evaluation of brain perfusion is key to the early diagnosis, treatment, and improved survival of neonates with hypoxic ischemic injury. Contrast-enhanced ultrasound (US) imaging is a novel imaging technique in which intravenously injected gas-filled microbubbles generate enhanced US echoes from an acoustic impedance mismatch. This article describes contrast-enhanced US imaging in 2 neonates with hypoxic ischemic injury and future directions on developing quantitative contrast-enhanced US techniques for improved characterization of perfusion abnormalities. The importance of studying the temporal evolution of brain perfusion in neonatal hypoxic ischemic injury is also highlighted.


Assuntos
Meios de Contraste , Hipóxia-Isquemia Encefálica/diagnóstico por imagem , Aumento da Imagem/métodos , Ultrassonografia/métodos , Encéfalo/diagnóstico por imagem , Humanos , Recém-Nascido , Masculino , Microbolhas
16.
Pediatr Radiol ; 46(2): 237-45, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26454840

RESUMO

BACKGROUND: When administered to an immune-compromised patient, BCG (Bacille Calmette-Guérin) can cause disseminated and life-threatening infections. OBJECTIVE: To describe the imaging findings in children with primary immunodeficiency and BCG-related infections. MATERIALS AND METHODS: We reviewed the imaging findings of children with primary immunodeficiency treated at a children's hospital during 2012-2014 with localized or disseminated BCG infection. Imaging modalities included US, CT and radiography. RESULTS: Nine children with primary immunodeficiency had clinical signs of post-vaccination BCGitis; seven of these children showed disseminated disease and two showed only regional lesions with characteristic ipsilateral lymphadenopathy. Overall, lymphadenopathy was the most prevalent feature (n = 8) and characteristically appeared as a ring-enhancing hypodense (CT) or hypoechoic (US) lesion. Visceral involvement with multiple abscesses appeared in the spleen (n = 2), liver (n = 1) and bones (n = 1). All lesions regressed following appropriate anti-tuberculosis treatment. CONCLUSION: BCG infection needs to be considered in children with typical findings and with suspected primary immunodeficiency.


Assuntos
Vacina BCG/efeitos adversos , Síndromes de Imunodeficiência/diagnóstico , Linfadenite/diagnóstico , Infecções por Mycobacterium/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Síndromes de Imunodeficiência/complicações , Síndromes de Imunodeficiência/imunologia , Lactente , Linfadenite/etiologia , Linfadenite/imunologia , Masculino , Infecções por Mycobacterium/etiologia , Infecções por Mycobacterium/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Ann Intern Med ; 160(9): 644-8, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24798526

RESUMO

On the night of 21 August 2013, sarin was dispersed in the eastern outskirts of Damascus, killing 1400 civilians and severely affecting thousands more. This article aims to delineate the clinical presentation and management of a mass casualty event caused by a nerve agent as shown in the social media. Authors searched YouTube for videos uploaded of this attack and identified 210 videos. Of these, 67 met inclusion criteria and were evaluated in the final analysis.These videos displayed 130 casualties; 119 (91.5%) of which were defined as moderately injured or worse. The most common clinical signs were dyspnea (53.0%), diaphoresis (48.5%), and loss of consciousness (40.7%). Important findings included a severe shortage of supporting measures and lack of antidotal autoinjectors. Decontamination, documented in 25% of the videos, was done in an inefficient manner. Protective gear was not noticed, except for sporadic use of latex gloves and surgical masks.This is believed to be the first time that social media was used to evaluate clinical data and management protocols to better prepare against future possible events.


Assuntos
Terrorismo Químico , Incidentes com Feridos em Massa , Sarina/intoxicação , Mídias Sociais , Atropina/uso terapêutico , Criança , Antagonistas Colinérgicos/uso terapêutico , Descontaminação , Planejamento em Desastres , Feminino , Humanos , Lactente , Injeções Intravenosas , Masculino , Intoxicação/complicações , Intoxicação/diagnóstico , Intoxicação/terapia , Síria/epidemiologia
18.
Epilepsia ; 55(12): 1953-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25377630

RESUMO

OBJECTIVE: Organophosphates (OPs) are commonly used insecticides for agriculture and domestic purposes, but may also serve as nerve agents. Exposure to OPs result in overstimulation of the cholinergic system and lead to status epilepticus (SE), a life-threatening condition that is often resistant to treatment. SE is associated with significant neuronal damage, neurocognitive dysfunction, and the development of lifelong epilepsy. Therefore, rapid termination of SE and prevention of brain damage is of high interest. Here we tested the efficacy of sec-butyl-propylacetamide (SPD) and two of its individual stereoisomers, (2S,3S)-SPD and (2R,3R)-SPD, in discontinuing OP-induced seizures. SPD is a one carbon homolog of valnoctamide, a central nervous system (CNS)-active constitutional isomer of valproic acid (VPA) corresponding amide valpromide. METHODS: Rats were implanted with epidural telemetric electrodes to allow electrocorticography (ECoG) recording 24 h prior, during and 24 h after poisoning with the OP paraoxon (at a dose equivalent to 1.4 LD50 Median lethal dose). All rats were provided with antidotal treatment of atropine and toxogonin. Epileptic activity was measured using a novel automated system to evaluate the different effects of midazolam, SPD, and its individual stereoisomers in comparison to nontreated controls. RESULTS: Treatment with SPD or its individual stereoisomer (2S,3S)-SPD significantly shorten paraoxon-induced SE and reduced the duration of recorded pathologic activity after SE was terminated. (2S,3S)-SPD was superior to racemic-SPD in diminishing delayed pathologic epileptiform activity within the first 8 h after SE. SIGNIFICANCE: These results suggest SPD as an efficient drug for the rapid termination of SE and pathological epileptiform activity following OP poisoning, a strategy to reduce neuronal dysfunction and the risk for lifelong epilepsy.


Assuntos
Amidas/uso terapêutico , Anticonvulsivantes/uso terapêutico , Estado Epiléptico/tratamento farmacológico , Ácido Valproico/análogos & derivados , Amidas/química , Animais , Anticonvulsivantes/química , Modelos Animais de Doenças , Eletroencefalografia , Inseticidas/toxicidade , Masculino , Paraoxon/toxicidade , Ratos , Ratos Sprague-Dawley , Estatísticas não Paramétricas , Estado Epiléptico/induzido quimicamente , Estereoisomerismo , Resultado do Tratamento , Ácido Valproico/química , Ácido Valproico/uso terapêutico
19.
Eur Radiol ; 24(6): 1251-6, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24663820

RESUMO

OBJECTIVES: The halo sign refers to a zone of ground-glass attenuation surrounding a pulmonary nodule. Pulmonary metastatic nodules exhibiting a halo sign are seen mainly in hypervascular tumours. We describe the appearance of a halo sign following treatment of adoptive transfer of autologous tumour-infiltrating lymphocytes (TIL) to melanoma patients with lung metastases. METHODS: The study included 29 melanoma patients with pulmonary metastases who received TIL therapy. Pre- and post-treatment chest CTs were retrospectively reviewed for the presence of a halo sign and its correlation with therapeutic response. RESULTS: A pulmonary halo sign was not seen in any pre-treatment CT. It was observed in four of 12 patients who responded to the therapy but not in those who failed to respond. Significant differences were found between response ratio in patients in whom post-TIL halo sign appeared compared with those without the halo sign (p = 0.02). CONCLUSIONS: The appearance of a CT halo sign in melanoma with lung metastases following TIL therapy may indicate antitumoral effect and a good response to therapy. Our findings emphasize the importance of applying new assessment criteria for immunological anticancer therapies. KEY POINTS: Tumour-infiltrating lymphocytes (TIL) in melanoma patients is a promising novel immunotherapy. Post-therapy pulmonary halo sign appeared in one-third of TIL responders . Pulmonary halo sign may serve as an imaging marker for antitumoral activity.


Assuntos
Imunoterapia Adotiva/métodos , Neoplasias Pulmonares , Melanoma , Neoplasias Cutâneas/patologia , Tomografia Computadorizada por Raios X/métodos , Adulto , Feminino , Seguimentos , Humanos , Pulmão/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/terapia , Linfócitos do Interstício Tumoral , Masculino , Melanoma/diagnóstico por imagem , Melanoma/secundário , Melanoma/terapia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Resultado do Tratamento
20.
Am J Emerg Med ; 32(12): 1445-9, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25440004

RESUMO

INTRODUCTION: Early respiratory support and airway (AW) control with endotracheal intubation (ETI) are crucial in mass toxicology events and must be performed while wearing chemical personal protective equipment (C-PPE). AIM: The aim of this study is to evaluate the efficiency of AW control by using second-generation supraglottic AW devices (SADs) as compared with ETI and first-generation SAD while wearing C-PPE. METHODS: This is a randomized crossover trial involving 117 medical practitioners. Four AW management devices were examined: endotracheal tube, the first-generation SAD, laryngeal mask AW unique and 2 second-generation SAD, the laryngeal tube suction disposable, and supreme laryngeal mask AW (SLMA). Primary end point measured were success or failure, number of attempts, and time needed to achieve successful device insertion. Secondary end point was a subjective appraisal of the AW devices by study population. RESULTS: More attempts were required to achieve AW control with endotracheal tube, with and without C-PPE (P<.001). Time to achieve AW control with ETI was, on average, 88% longer than required with other devices and improved with practice. The mean times to achieve an AW were longer when operators were equipped with C-PPE as compared with standard clothing. Subjectively, difficulty levels were significantly higher for ETI than for all other devices (P<.0001). CONCLUSIONS: When compared with ETI, the use of SADs significantly shortened the time for AW control while wearing C-PPE. Second-generation SAD were superior to laryngeal mask AW unique. These finding suggest that SADs may be used in a mass toxicology event as a bridge, until definite AW control is achieved.


Assuntos
Intubação Intratraqueal/instrumentação , Incidentes com Feridos em Massa , Adulto , Pessoal Técnico de Saúde , Guerra Química , Competência Clínica , Estudos Cross-Over , Humanos , Intubação Intratraqueal/métodos , Máscaras Laríngeas , Médicos , Roupa de Proteção , Fatores de Tempo , Adulto Jovem
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