RESUMEN
AIM: To retrospectively compare the utility of perfusion magnetic resonance imaging (MRI) in distinguishing treatment-related changes from recurrent disease in glioma patients. MATERIALS AND METHODS: Thirty-one patients with histologically diagnosed gliomas and increased enhancement after or during concurrent (chemo-) radiation therapy were enrolled. They underwent dynamic contrast-enhanced (DCE) permeability MRI followed by dynamic susceptibility contrast (DSC) perfusion MRI. The vascular transfer constant (rK(trans)) and initial areas under the concentration curve (riAUC) were obtained from DCE MRI, and cerebral blood volume (rCBV) was obtained from DSC MRI. Patients were classified as having treatment-related changes or recurrent tumours based on clinicoradiological results or pathological results from surgery. RESULTS: Nineteen patients were diagnosed as having recurrences and 12 patients as having treatment-related changes. The rK(trans), riAUC, and rCBV values in the recurrent group were significantly higher than the values in the group with treatment-related changes (p < 0.05). For all 31 patients, there was no significant difference between DSC MRI and DCE MRI for the differentiating power between recurrence and treatment-related changes (p = 0.7227). However, when including only the 24 patients with concordant values of rK(trans) and riAUC, DCE MRI showed a significant AUC value of 0.786 in the receiver operating characteristic (ROC) curve analysis (p = 0.003), whereas DSC MRI did not (AUC = 0.643, p = 0.229). CONCLUSION: MRI perfusion images appear to show promise in distinguishing treatment-related changes from recurrent tumours. When both rK(trans) and riAUC show concordant values, DCE MRI seems to be more powerful than DSC MRI in the differentiation of recurrence from treatment-related changes.
Asunto(s)
Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Angiografía por Resonancia Magnética/métodos , Recurrencia Local de Neoplasia/diagnóstico , Adulto , Anciano , Medios de Contraste , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Estudios RetrospectivosRESUMEN
AIM: To describe the frequency, pattern, and outcome of chest radiographic abnormalities in children with H1N1 influenza infection. MATERIALS AND METHODS: Three hundred and fourteen paediatric patients with confirmed H1N1 influenza infection who underwent chest radiography at presentation at a single institution during the outbreak in 2009 were retrospectively reviewed. Abnormal chest radiographic findings related to acute infection were analysed in terms of frequency, pattern, and distribution. Medical records and follow-up radiographs were also reviewed to assess clinical features and outcomes. RESULTS: Chest lesions suggesting acute infection were identified in 49 (16%) patients (mean age 8.2 years, range approximately 1.8-18.5 years). The most common finding was prominent peribronchial marking (71%), followed by air-space opacity (51%) with or without volume decrease, generalized hyperinflation (24%), and pleural effusion (20%). Other minor findings included pneumomediastinum (n=2) and a nodule (n=1). Distributions were bilateral (55%) or unilateral (45%) with frequent involvement of lower (78%), and middle (59%) lung zones. Thirty-nine patients (80%) were hospitalized and six (12%) required mechanical ventilation, followed by recovery. Thirty-one out of the 33 patients that underwent follow-up radiography showed marked resolution of all radiographic abnormalities. CONCLUSION: The frequency of a chest radiographic abnormality was found to be low in children with H1N1 influenza infection. Although typical radiographic findings of a viral lower respiratory infection were more common, unilateral involvement and air-space opacity were common, often with pleural effusion. Furthermore, pulmonary lesions showed near complete resolution on follow-up radiographs in the majority of patients.
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Subtipo H1N1 del Virus de la Influenza A/aislamiento & purificación , Gripe Humana/diagnóstico por imagen , Adolescente , Distribución por Edad , Niño , Preescolar , Brotes de Enfermedades , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Lactante , Gripe Humana/epidemiología , Masculino , Variaciones Dependientes del Observador , Radiografía , Estudios Retrospectivos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Resultado del TratamientoRESUMEN
This report analyzes variations in the age distribution of individuals at selection to three prominent positions in the academic-professional community. Nobel prizewinner, president of a scientific or professional association, and president of a major research-oriented university. The mean ages of the individuals in each of the categories are compared with those of the presumed pool of scientists. The cross-sectional variations in age at selection seem to be correlated with variations in the levels of codification among the disciplines. There has been a tendency toward older selectees over time. The aging of the pool of scientists cannot fully account for this aging trend. A backlog of candidates for recognition seems to be implicated.