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1.
Pediatr Radiol ; 48(11): 1606-1611, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29926146

RESUMO

BACKGROUND: A multidisciplinary urinary tract dilation (UTD) classification system was published in 2014 to standardize definitions and renal/bladder ultrasound image interpretation. OBJECTIVE: To evaluate intra- and inter-rater reliability of this system on postnatal RBUS. MATERIALS AND METHODS: Renal/bladder US of 60 infants (<12 months) with urinary tract dilation were anonymized, retrospectively reviewed and scored twice using the UTD classification system by a pediatric urologist and four pediatric radiologists. Exams included supine and prone images of each kidney. Raters recorded the anterior posterior renal pelvis diameter in each position; and when present calyceal dilation (central and peripheral), ureteral dilation, parenchymal and bladder abnormalities. A UTD score was given to each kidney based on these components. RESULTS: Intraclass correlation (ICC) of anterior posterior renal pelvis diameter measures was 0.99 (P<0.001). Intra-rater reliability for the anterior posterior renal pelvis diameter of each kidney was high, with ICC >0.95 (P<0.001). Inter-rater kappa values for UTD scores of both kidneys ranged from 0.60 to 0.77 (P <0.001). Intra-rater kappa values for UTD scores of both kidneys ranged from 0.74 to 0.92 (P <0.001). Of the six categories comprising the UTD score, discrepancy between raters was highest for interpretation of central and peripheral calyceal dilation. CONCLUSION: Present inter- and intra-rater reliability findings were similar to those previously reported for grading systems for urinary tract dilation. Across these studies, kappa values are generally lower than the 0.8 cut-off advocated for medical measures. Here, calyceal dilation commonly determined the kidney UTD score and was also the source of greatest discrepancy between raters. Improving consistency of calyceal dilation interpretation may improve UTD consensus score reliability.


Assuntos
Ultrassonografia/métodos , Anormalidades Urogenitais/classificação , Anormalidades Urogenitais/diagnóstico por imagem , Consenso , Dilatação Patológica , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Reprodutibilidade dos Testes
2.
Pediatr Radiol ; 48(2): 216-226, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29181582

RESUMO

BACKGROUND: Contrast-enhanced voiding urosonography (ceVUS) is widely used outside the United States to diagnose vesicoureteral reflux (VUR) in children and is highly sensitive while avoiding exposure to ionizing radiation. At the onset of this study, two ultrasound (US) contrast agents were available in the United States. Pediatric safety data for intravenous administration was published for one, Optison™. OBJECTIVE: This study aimed to evaluate the diagnostic performance and safety of ceVUS using Optison™ and compare its diagnostic efficacy with voiding cystourethrogram (VCUG) for VUR detection and grading in children. MATERIALS AND METHODS: The United States Food and Drug Administration and institutional Investigational New Drug authorizations were obtained to conduct a prospective comparative study of ceVUS with Optison™ and VCUG. CeVUS was performed with intravesical administration of 0.2% Optison™/normal saline solution. A standard VCUG followed. Safety assessment included physical examination, and heart rate, pulse oximetry and adverse reactions monitoring before, during and immediately after the examinations. A follow-up questionnaire was completed by telephone 48-h after the studies. RESULTS: Sixty-two pelviureteric units were studied in 30 patients with a mean age of 3.5 years (range: 0.1-17 years) including 21 girls and 9 boys. No severe adverse events occurred. All patients had normal heart rate and blood oxygenation saturation prior to, during and after the studies. At the 48-h follow-up, one patient (3.3%) reported transient dysuria. Taking the VCUG as the reference standard, ceVUS had a sensitivity of 91.7% (95%; confidence interval [CI]: 61.5%-99.8%) and specificity of 98% (95%; CI: 89.4%-99.9%). The concordance between ceVUS and VCUG for VUR detection and grading was 84.3% and 81.8%, respectively. VUR grades were discrepant in 4/11 refluxing pelviureteric units, with VCUG upgrading VUR in 2. CONCLUSION: Detection of VUR with Optison™ ceVUS was comparable to VCUG without exposure to ionizing radiation. CeVUS with Optison™ is a well-tolerated diagnostic procedure with a favorable safety profile.


Assuntos
Albuminas/administração & dosagem , Meios de Contraste/administração & dosagem , Fluorocarbonos/administração & dosagem , Refluxo Vesicoureteral/diagnóstico por imagem , Administração Intravesical , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos , Sensibilidade e Especificidade
3.
Hum Brain Mapp ; 34(1): 1-11, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21932258

RESUMO

Regions of the fusiform gyrus (FG) respond preferentially to faces over other classes of visual stimuli. It remains unclear whether emotional face information modulates FG activity. In the present study, whole-head magnetoencephalography (MEG) was obtained from fifteen healthy adults who viewed emotionally expressive faces and made button responses based upon emotion (explicit condition) or age (implicit condition). Dipole source modeling produced source waveforms for left and right primary visual and left and right fusiform areas. Stronger left FG activity (M170) to fearful than happy or neutral faces was observed only in the explicit task, suggesting that directed attention to the emotional content of faces facilitates observation of M170 valence modulation. A strong association between M170 FG activity and reaction times in the explicit task provided additional evidence for a role of the fusiform gyrus in processing emotional information.


Assuntos
Córtex Cerebral/fisiologia , Emoções/fisiologia , Expressão Facial , Magnetoencefalografia , Reconhecimento Visual de Modelos/fisiologia , Adulto , Atenção/fisiologia , Mapeamento Encefálico/métodos , Potenciais Evocados Visuais/fisiologia , Face , Medo , Feminino , Felicidade , Humanos , Masculino , Estimulação Luminosa/métodos , Tempo de Reação/fisiologia , Adulto Jovem
4.
Pediatr Radiol ; 40(12): 1874-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20490482

RESUMO

BACKGROUND: The sensitivity and specificity of evaluating clubfoot deformity by MR in high-risk fetuses is currently unknown. OBJECTIVE: To correlate fetal MRI with US in the assessment of clubfoot and to identify the MRI features most characteristic of clubfoot. MATERIALS AND METHODS: With IRB approval and informed consent, the presence of fetal clubfoot was prospectively evaluated in mothers referred for MRI for a fetus with myelomeningocele. Two radiologists blind to the US results independently reviewed the MRI for the presence of clubfoot. MRI results were compared with US results obtained the same day and birth outcomes. RESULTS: Of 20 patients enrolled, there were 13 clubfeet. Interobserver agreement for the presence of clubfoot was 100%. The sensitivity of the MRI exam was 100% and the specificity 85.2%. A dedicated sagittal imaging plane through the ankle region allowed the most confident diagnosis; medial deviation of the foot relative to the leg was seen in all 13 fetuses with clubfoot. CONCLUSION: The correlation of fetal MRI with US in the evaluation of clubfoot yields a sensitivity of 100% and specificity of 85.2%. The sagittal plane provided the most useful information.


Assuntos
Anormalidades Múltiplas/diagnóstico , Pé Torto Equinovaro/diagnóstico , Imageamento por Ressonância Magnética/métodos , Meningomielocele/diagnóstico , Diagnóstico Pré-Natal/métodos , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Método Simples-Cego
5.
Soc Cogn Affect Neurosci ; 11(9): 1440-8, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27272198

RESUMO

Facial threat is associated with changes in limbic activity as well as modifications in the cortical face-related N170. It remains unclear if task-irrelevant threat modulates the response to a subsequent facial stimulus, and whether the amygdala's role in early threat perception is independent and direct, or modulatory. In 19 participants, crowds of emotional faces were followed by target faces and a rating task while simultaneous EEG-fMRI were recorded. In addition to conventional analyses, fMRI-informed EEG analyses and fMRI dynamic causal modeling (DCM) were performed. Fearful crowds reduced EEG N170 target face amplitudes and increased responses in a fMRI network comprising insula, amygdala and inferior frontal cortex. Multimodal analyses showed that amygdala response was present ∼60 ms before the right fusiform gyrus-derived N170. DCM indicated inhibitory connections from amygdala to fusiform gyrus, strengthened when fearful crowds preceded a target face. Results demonstrated the suppressing influence of task-irrelevant fearful crowds on subsequent face processing. The amygdala may be sensitive to task-irrelevant fearful crowds and subsequently strengthen its inhibitory influence on face-responsive fusiform N170 generators. This provides spatiotemporal evidence for a feedback mechanism of the amygdala by narrowing attention in order to focus on potential threats.


Assuntos
Tonsila do Cerebelo/fisiologia , Face , Medo/psicologia , Lobo Temporal/fisiologia , Percepção Visual/fisiologia , Adulto , Atenção/fisiologia , Eletroencefalografia , Emoções , Expressão Facial , Retroalimentação Psicológica , Feminino , Lobo Frontal/fisiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Modelos Neurológicos
6.
J Autism Dev Disord ; 45(2): 444-60, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23963593

RESUMO

Examination of resting state brain activity using electrophysiological measures like complexity as well as functional connectivity is of growing interest in the study of autism spectrum disorders (ASD). The present paper jointly examined complexity and connectivity to obtain a more detailed characterization of resting state brain activity in ASD. Multi-scale entropy was computed to quantify the signal complexity, and synchronization likelihood was used to evaluate functional connectivity (FC), with node strength values providing a sensor-level measure of connectivity to facilitate comparisons with complexity. Sensor level analysis of complexity and connectivity was performed at different frequency bands computed from resting state MEG from 26 children with ASD and 22 typically developing controls (TD). Analyses revealed band-specific group differences in each measure that agreed with other functional studies in fMRI and EEG: higher complexity in TD than ASD, in frontal regions in the delta band and occipital-parietal regions in the alpha band, and lower complexity in TD than in ASD in delta (parietal regions), theta (central and temporal regions) and gamma (frontal-central boundary regions); increased short-range connectivity in ASD in the frontal lobe in the delta band and long-range connectivity in the temporal, parietal and occipital lobes in the alpha band. Finally, and perhaps most strikingly, group differences between ASD and TD in complexity and FC appear spatially complementary, such that where FC was elevated in ASD, complexity was reduced (and vice versa). The correlation of regional average complexity and connectivity node strength with symptom severity scores of ASD subjects supported the overall complementarity (with opposing sign) of connectivity and complexity measures, pointing to either diminished connectivity leading to elevated entropy due to poor inhibitory regulation or chaotic signals prohibiting effective measure of connectivity.


Assuntos
Transtorno Autístico/fisiopatologia , Lobo Frontal/fisiopatologia , Lobo Occipital/fisiopatologia , Lobo Parietal/fisiopatologia , Lobo Temporal/fisiopatologia , Adolescente , Estudos de Casos e Controles , Criança , Humanos , Magnetoencefalografia , Vias Neurais/fisiopatologia , Escalas de Graduação Psiquiátrica , Descanso
7.
Neuroimage Clin ; 5: 109-19, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25009772

RESUMO

Traumatic brain injury (TBI) is a leading cause of sustained impairment in military and civilian populations. However, mild TBI (mTBI) can be difficult to detect using conventional MRI or CT. Injured brain tissues in mTBI patients generate abnormal slow-waves (1-4 Hz) that can be measured and localized by resting-state magnetoencephalography (MEG). In this study, we develop a voxel-based whole-brain MEG slow-wave imaging approach for detecting abnormality in patients with mTBI on a single-subject basis. A normative database of resting-state MEG source magnitude images (1-4 Hz) from 79 healthy control subjects was established for all brain voxels. The high-resolution MEG source magnitude images were obtained by our recent Fast-VESTAL method. In 84 mTBI patients with persistent post-concussive symptoms (36 from blasts, and 48 from non-blast causes), our method detected abnormalities at the positive detection rates of 84.5%, 86.1%, and 83.3% for the combined (blast-induced plus with non-blast causes), blast, and non-blast mTBI groups, respectively. We found that prefrontal, posterior parietal, inferior temporal, hippocampus, and cerebella areas were particularly vulnerable to head trauma. The result also showed that MEG slow-wave generation in prefrontal areas positively correlated with personality change, trouble concentrating, affective lability, and depression symptoms. Discussion is provided regarding the neuronal mechanisms of MEG slow-wave generation due to deafferentation caused by axonal injury and/or blockages/limitations of cholinergic transmission in TBI. This study provides an effective way for using MEG slow-wave source imaging to localize affected areas and supports MEG as a tool for assisting the diagnosis of mTBI.


Assuntos
Traumatismos por Explosões/complicações , Lesões Encefálicas/diagnóstico , Traumatismos Craniocerebrais/complicações , Síndrome Pós-Concussão/diagnóstico , Acidentes de Trânsito , Adulto , Traumatismos por Explosões/fisiopatologia , Lesões Encefálicas/etiologia , Lesões Encefálicas/fisiopatologia , Traumatismos Craniocerebrais/fisiopatologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Magnetoencefalografia , Masculino , Testes Neuropsicológicos , Síndrome Pós-Concussão/etiologia , Síndrome Pós-Concussão/fisiopatologia , Sensibilidade e Especificidade , Adulto Jovem
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