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1.
Eur J Radiol ; 164: 110865, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37167684

RESUMEN

PURPOSE: The Prostate Imaging Quality (PI-QUAL) score is a metric to evaluate the diagnostic quality of multiparametric magnetic resonance imaging (MRI) of the prostate. This study evaluated the impact of a prostate MRI quality training lecture on the participant's ability to assess prostate MRI image quality. METHODS: Eighteen in-training-radiologists of varying experience in reviewing diagnostic prostate MRI assessed the image quality of ten examinations. Then, they attended a dedicated lecture on MRI quality assessment using the PI-QUAL score. After the lecture, the same participants evaluated the image quality of a new set of ten scans applying the PI-QUAL score. Results were assessed using receiver operating characteristic (ROC) analysis. The reference standard was the PI-QUAL score assessed by a fellowship trained abdominal radiologist with experience in reading prostate MRI. RESULTS: There was a significant improvement in the average area under the curve (AUC) for assessment of prostate MRI image quality from baseline (0.82; [0.576 - 0.888]) to post teaching (1.0; [0.954-1]), with an improvement of 0.18 (p < 0.03). When ROC curves were computed for different cohorts stratified based on year of training, difference ranged from 0.48 for second year residents to 0.32 for fourth year residents (p < 0.001-0.01). For abdominal imaging fellows, the pre-teaching AUC was 0.9 [0.557-1] and post teaching AUC was 1 [0.957-1], a difference of 0.1 (p = 0.20). CONCLUSIONS: A dedicated lecture on PI-QUAL improved the ability of radiologists-in-training to assess prostate MRI image quality, with variable impact depending on year of training.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de la Próstata , Masculino , Humanos , Próstata/diagnóstico por imagen , Próstata/patología , Neoplasias de la Próstata/patología , Imagen por Resonancia Magnética/métodos , Curriculum , Estudios Retrospectivos
2.
Sci Rep ; 12(1): 20315, 2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36434070

RESUMEN

Hepatocellular carcinoma (HCC) has become the 4th leading cause of cancer-related deaths, with high social, economical and health implications. Imaging techniques such as multiphase computed tomography (CT) have been successfully used for diagnosis of liver tumors such as HCC in a feasible and accurate way and its interpretation relies mainly on comparing the appearance of the lesions in the different contrast phases of the exam. Recently, some researchers have been dedicated to the development of tools based on machine learning (ML) algorithms, especially by deep learning techniques, to improve the diagnosis of liver lesions in imaging exams. However, the lack of standardization in the naming of the CT contrast phases in the DICOM metadata is a problem for real-life deployment of machine learning tools. Therefore, it is important to correctly identify the exam phase based only on the image and not on the exam metadata, which is unreliable. Motivated by this problem, we successfully created an annotation platform and implemented a convolutional neural network (CNN) to automatically identify the CT scan phases in the HCFMUSP database in the city of São Paulo, Brazil. We improved this algorithm with hyperparameter tuning and evaluated it with cross validation methods. Comparing its predictions with the radiologists annotation, it achieved an accuracy of 94.6%, 98% and 100% in the testing dataset for the slice, volume and exam evaluation, respectively.


Asunto(s)
Carcinoma Hepatocelular , Aprendizaje Profundo , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Brasil , Tomografía Computarizada por Rayos X/métodos , Computadores
3.
Viruses ; 14(2)2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35215772

RESUMEN

Identification of the SARS-CoV-2 virus by RT-PCR from a nasopharyngeal swab sample is a common test for diagnosing COVID-19. However, some patients present clinical, laboratorial, and radiological evidence of COVID-19 infection with negative RT-PCR result(s). Thus, we assessed whether positive results were associated with intubation and mortality. This study was conducted in a Brazilian tertiary hospital from March to August of 2020. All patients had clinical, laboratory, and radiological diagnosis of COVID-19. They were divided into two groups: positive (+) RT-PCR group, with 2292 participants, and negative (-) RT-PCR group, with 706 participants. Patients with negative RT-PCR testing and an alternative most probable diagnosis were excluded from the study. The RT-PCR(+) group presented increased risk of intensive care unit (ICU) admission, mechanical ventilation, length of hospital stay, and 28-day mortality, when compared to the RT-PCR(-) group. A positive SARS-CoV-2 RT-PCR result was independently associated with intubation and 28 day in-hospital mortality. Accordingly, we concluded that patients with a COVID-19 diagnosis based on clinical data, despite a negative RT-PCR test from nasopharyngeal samples, presented more favorable outcomes than patients with positive RT-PCR test(s).


Asunto(s)
Prueba de Ácido Nucleico para COVID-19/estadística & datos numéricos , COVID-19/diagnóstico , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/estadística & datos numéricos , SARS-CoV-2/genética , Centros Médicos Académicos/estadística & datos numéricos , Anciano , Brasil , COVID-19/mortalidad , COVID-19/virología , Prueba de Ácido Nucleico para COVID-19/métodos , Femenino , Mortalidad Hospitalaria , Hospitalización/estadística & datos numéricos , Humanos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Nasofaringe/virología , Estudios Retrospectivos , Factores de Riesgo
4.
Healthcare (Basel) ; 10(2)2022 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-35206821

RESUMEN

BACKGROUND: The decision to intubate COVID-19 patients receiving non-invasive respiratory support is challenging, requiring a fine balance between early intubation and risks of invasive mechanical ventilation versus the adverse effects of delaying intubation. This present study analyzes the association between intubation day and mortality in COVID-19 patients. METHODS: We performed a unicentric retrospective cohort study considering all COVID-19 patients consecutively admitted between March 2020 and August 2020 requiring invasive mechanical ventilation. The primary outcome was all-cause mortality within 28 days after intubation, and a Cox model was used to evaluate the effect of time from onset of symptoms to intubation in mortality. RESULTS: A total of 592 (20%) patients of 3020 admitted with COVID-19 were intubated during study period, and 310 patients who were intubated deceased 28 days after intubation. Each additional day between the onset of symptoms and intubation was significantly associated with higher in-hospital death (adjusted hazard ratio, 1.018; 95% CI, 1.005-1.03). CONCLUSION: Among patients infected with SARS-CoV-2 who were intubated and mechanically ventilated, delaying intubation in the course of symptoms may be associated with higher mortality. TRIAL REGISTRATION: The study protocol was approved by the local Ethics Committee (opinion number 3.990.817; CAAE: 30417520.0.0000.0068).

6.
Value Health Reg Issues ; 23: 25-29, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32199171

RESUMEN

OBJECTIVES: As health systems start to discuss alternative payment models for fostering value in healthcare, there is increased interest in understanding how physicians will cope with different remuneration schemes. We conducted a survey of physicians practicing at Hospital Israelita Albert Einstein, a nonprofit private healthcare provider in Brazil, aimed at capturing their awareness of value-based healthcare (VBHC). METHODS: Our study uses data from a survey administered to doctors practicing at Einstein between September and November 2018. Descriptive statistics and adjusted multivariate logistic regression analyses were used to describe physicians' characteristics associated with their views on VBHC. RESULTS: A total of 1000 physicians completed the survey (response rate: 13%). Although only 25% knew the value equation, 67% defined value in health according to Porter's-the outcomes that matter to patients in relation to the costs of offering such outcomes. Most participants identified increased healthcare costs as the main reason for the discussions over new financing models. Only 27% of physicians rated their awareness of VBHC as high or very high. In the multivariate analysis, awareness of VBHC was associated with holding a management position, scoring high in the hospital's physician segmentation program, being familiar with the value equation, and attributing high importance to developing new VBHC financing models for health system transformation. CONCLUSIONS: Physician awareness of key VBHC concepts is still heterogeneous in our clinical setting. Promoting opportunities for involving physicians in the discussion of VBHC is key for a successful value-driven transformation of healthcare.


Asunto(s)
Médicos/psicología , Mecanismo de Reembolso/normas , Brasil , Costos de la Atención en Salud/normas , Humanos , Médicos/estadística & datos numéricos , Práctica Privada/organización & administración , Práctica Privada/estadística & datos numéricos , Mecanismo de Reembolso/estadística & datos numéricos , Encuestas y Cuestionarios
7.
Rev. Soc. Cardiol. Estado de Säo Paulo ; 30(3): 352-357, jul., 2020. ilus., tab.
Artículo en Portugués | Sec. Est. Saúde SP, CONASS, SESSP-IDPCPROD, Sec. Est. Saúde SP | ID: biblio-1223739

RESUMEN

Estima-se que metade dos 3,2 bilhões de prescrições médicas realizadas anualmente nos EUA não são seguidas corretamente. A baixa adesão terapêutica determina menor eficiência dos fármacos e, além disso, eleva a morbidade das condições clinicas e leva a internações hospitalares que poderiam ser evitadas, o que gera impacto social e econômico. A ciência comportamental pode instrumentalizar o médico para permitir um diagnóstico de adesão e, principalmente, interferir e melhorar o engajamento do paciente. As principais teorias comportamentais aplicáveis são: a) modelo de crença em saúde que trabalha a percepção de risco da doença, além de barreiras e benefí-cios do tratamento; b) conceito de estágios de mudança, que considera os diferentes estágios de aptidão para mudança: pré-contemplação, contemplação, planejamento, ação e persistência; c) teoria cognitivo-social que leva em consideração experiências pessoais e do grupo para viabilizar mudanças. O uso de tecnologias em saúde per-mite ampliar as ações que visam aumentar o engajamento do paciente. De maneira geral, pacientes que têm um dispositivo que permita algum monitoramento têm maior chance de engajamento na saúde. Os sistemas de mensageria são simples e efetivos como lembretes periódicos para o paciente persistir em níveis adequados de adesão e são ferramentas que permitem o contato com o paciente (teleconsultas e telemoni-toramento) nos períodos entre as consultas presencias, especialmente os pacientes com doenças crônicas não transmissíveis como hipertensão arterial e insuficiência cardíaca, entre outras.


Asunto(s)
Ciencia , Tecnología , Cumplimiento de la Medicación , Sociedades
8.
PLoS One ; 10(5): e0126362, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25969982

RESUMEN

PURPOSE: To evaluate the functional magnetic resonance imaging (fMRI) response to binocular visual stimulation and the association thereof with structural ocular findings and psychophysical test results in patients with glaucoma, and controls. METHODS: Cross-sectional study. Participants underwent a complete ophthalmic examination, including Humphrey 24-2 visual field (VF) testing and optical coherence tomography. Binocular VF in each quadrant was determined using an integrated method. Patients with glaucoma were assigned to three subgroups: initial, asymmetrical and severe glaucoma. Regions of interest (ROIs) were determined anatomically. fMRI (3 T) was performed using a bilaterally presented polar angle stimulus, and the accompanying changes in blood oxygen level-dependent (BOLD) signals were obtained from the occipital poles and calcarine ROIs. We used generalized estimation equation models to compare anatomical and functional data between the groups. RESULTS: A total of 25 subjects were enrolled, of whom 17 had glaucoma and 8 were controls. Significant associations between quadrant binocular VF sensitivities and fMRI responses were found in the occipital pole ROIs (p = 0.033) and the calcarine ROIs (p = 0.045). In glaucoma severity subgroup analysis, retinal nerve fiber layer (RNFL) thickness was associated with the BOLD response of the calcarine and occipital pole ROIs (p = 0.002 and 0.026, respectively). The initial and asymmetrical glaucoma subgroups had similar binocular VF sensitivities and RNFL thicknesses, but distinct BOLD responses. CONCLUSIONS: The response of the visual cortex to binocular stimulation was associated with binocular VF sensitivity. RNFL thickness was associated with the BOLD response of the calcarine and occipital pole ROIs.


Asunto(s)
Glaucoma/patología , Glaucoma/fisiopatología , Corteza Visual/fisiopatología , Adulto , Anciano , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Nervio Óptico/patología , Estimulación Luminosa , Psicofísica , Tomografía de Coherencia Óptica , Campos Visuales
9.
Managua; s.n; ago. 2009. 93 p. tab, graf.
Tesis en Español | LILACS | ID: lil-592881

RESUMEN

Se realizó un estudio descriptivo, longitudinal, prospectivo en el Centro Nacional de Oftalmología, durante el período Julio 2007 a Noviembre 2008 con el objetivo de determinar la eficacia de la membrana amniótica en el tratamiento quirúrgico del pterigión recidivante. El Universo lo constituyeron todos los pacientes que asistieron a consulta por pterigión recidivante en el período Julio 2007 – Noviembre 2008 en el Centro Nacional de Oftalmología. La Muestra estuvo conformada por 43 pacientes que tenían historia de pterigión recidivante de 1 año o mas de evolución en el mismo período. Entre los resultados más importantes se destacan que la mayoría de los pacientes tenían entre 36 y 55 años, femeninos, de procedencia urbana, 1 cirugía de pterigión previa y de 1 a 3 años de haber sido operados. El corte evaluativo se realizó cuando todos los pacientes tenían al menos 3 meses de intervención. 4 pacientes presentaron recidiva (9.3%), teniendo estos las características de ser masculinos, del grupo etáreo de 36 a 55 años y 1 cirugía previa. Se concluyó que el uso de membrana amniótica como tratamiento de pterigión recidivante es un método seguro y eficaz en un 90.7%. Se recomendó la implementación del uso de membrana amniótica en pacientes con pterigión recidivante, a fin de reducir el porcentaje de recidivas...


Asunto(s)
Amnios , Betametasona/administración & dosificación , Betametasona/uso terapéutico , Hipotensión Ocular/complicaciones , Pterigion/cirugía , Pterigion/terapia , Úlcera de la Córnea/complicaciones
10.
Arq Neuropsiquiatr ; 65(2A): 358-61, 2007 Jun.
Artículo en Portugués | MEDLINE | ID: mdl-17607446

RESUMEN

Acute necrotizing encephalopathy was initially reported in Japanese children. The rapid evolution and symmetrical brain lesions seen in the brainstem, cerebellum and specially in the thalamus characterize the disease. We studied a 7-month-old-girl, who presented with two episodes of rapid loss of consciousness and paresis without metabolic disturbances. At the first time she had a rapid improvement, but at the second episode the course was fulminant and in two days she lapsed into a clinical state of brain death. The magnetic resonance studies showed symmetrical lesions in the thalamus and additional lesions involving the brainstem and the cerebellum.


Asunto(s)
Encéfalo/patología , Enfermedad de Leigh/patología , Resultado Fatal , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética
11.
Arq. neuropsiquiatr ; 65(2A): 358-361, jun. 2007. tab, ilus
Artículo en Portugués | LILACS | ID: lil-453944

RESUMEN

A encefalopatia necrotizante aguda foi descrita inicialmente em crianças japonesas e se caracteriza por rápida evolução e lesões simétricas no tronco encefálico, cerebelo e especialmente nos tálamos. Avaliamos uma menina de 7 meses de idade, que apresentou dois episódios de depressão da consciência de rápida instalação e paresias, sem alterações metabólicas. Houve uma rápida melhora na primeira crise, porém o segundo episódio foi fulminante, tendo evoluído para estado de morte encefálica em dois dias. Os estudos de ressonância magnética mostraram lesões simétricas nos tálamos e acometimento também do tronco encefálico e cerebelo.


Acute necrotizing encephalopathy was initially reported in Japanese children. The rapid evolution and symmetrical brain lesions seen in the brainstem, cerebellum and specially in the thalamus characterize the disease. We studied a 7-month-old-girl, who presented with two episodes of rapid loss of consciousness and paresis without metabolic disturbances. At the first time she had a rapid improvement, but at the second episode the course was fulminant and in two days she lapsed into a clinical state of brain death. The magnetic resonance studies showed symmetrical lesions in the thalamus and additional lesions involving the brainstem and the cerebellum.


Asunto(s)
Femenino , Humanos , Lactante , Encéfalo/patología , Enfermedad de Leigh/patología , Resultado Fatal , Imagen por Resonancia Magnética
12.
Neuroimage ; 31(1): 187-96, 2006 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-16434214

RESUMEN

Functional magnetic resonance imaging (fMRI) is widely used to identify neural correlates of cognitive tasks. However, the analysis of functional connectivity is crucial to understanding neural dynamics. Although many studies of cerebral circuitry have revealed adaptative behavior, which can change during the course of the experiment, most of contemporary connectivity studies are based on correlational analysis or structural equations analysis, assuming a time-invariant connectivity structure. In this paper, a novel method of continuous time-varying connectivity analysis is proposed, based on the wavelet expansion of functions and vector autoregressive model (wavelet dynamic vector autoregressive-DVAR). The model also allows identification of the direction of information flow between brain areas, extending the Granger causality concept to locally stationary processes. Simulation results show a good performance of this approach even using short time intervals. The application of this new approach is illustrated with fMRI data from a simple AB motor task experiment.


Asunto(s)
Corteza Cerebral/fisiología , Aumento de la Imagen/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Modelos Estadísticos , Actividad Motora/fisiología , Red Nerviosa/fisiología , Oxígeno/sangre , Análisis de Regresión , Adulto , Mapeo Encefálico , Corteza Cerebral/anatomía & histología , Simulación por Computador , Femenino , Humanos , Red Nerviosa/anatomía & histología , Valores de Referencia
13.
J Neuroimaging ; 15(2): 203-5, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15746236

RESUMEN

Transient global amnesia is a benign syndrome of sudden-onset alteration of behavior with temporary dysfunction of anterograde and recent retrograde memory. Its neural substrates remain uncertain. Possible causes include ischemia, migraine, and epilepsy. The authors report a case of a 62-year-old man with a transient attack of memory disturbance, suggestive of transient global amnesia, in which magnetic resonance imaging performed 48 hours after onset showed left mesial temporal lobe signal changes on diffusion-weighted imaging and fluid-attenuated inversion recovery images. The findings and a literature review lend further support to the ischemic pathogenesis of transient global amnesia as a possible etiology, and underscore the role of diffusion-weighted imaging in the diagnosis of this condition.


Asunto(s)
Amnesia Global Transitoria/etiología , Isquemia Encefálica/diagnóstico , Imagen por Resonancia Magnética/métodos , Isquemia Encefálica/complicaciones , Imagen de Difusión por Resonancia Magnética/métodos , Estudios de Seguimiento , Hipocampo/patología , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Lóbulo Temporal/patología
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