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1.
Int J Cardiovasc Imaging ; 39(7): 1313-1321, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37150757

RESUMEN

We sought to determine the cardiac ultrasound view of greatest quality using a machine learning (ML) approach on a cohort of transthoracic echocardiograms (TTE) with abnormal left ventricular (LV) systolic function. We utilize an ML model to determine the TTE view of highest quality when scanned by sonographers. A random sample of TTEs with reported LV dysfunction from 09/25/2017-01/15/2019 were downloaded from the regional database. Component video files were analyzed using ML models that jointly classified view and image quality. The model consisted of convolutional layers for extracting spatial features and Long Short-term Memory units to temporally aggregate the frame-wise spatial embeddings. We report the view-specific quality scores for each TTE. Pair-wise comparisons amongst views were performed with Wilcoxon signed-rank test. Of 1,145 TTEs analyzed by the ML model, 74.5% were from males and mean LV ejection fraction was 43.1 ± 9.9%. Maximum quality score was best for the apical 4 chamber (AP4) view (70.6 ± 13.9%, p<0.001 compared to all other views) and worst for the apical 2 chamber (AP2) view (60.4 ± 15.4%, p<0.001 for all views except parasternal short-axis view at mitral/papillary muscle level, PSAX M/PM). In TTEs scanned by professional sonographers, the view with greatest ML-derived quality was the AP4 view.


Asunto(s)
Ecocardiografía , Disfunción Ventricular Izquierda , Masculino , Humanos , Valor Predictivo de las Pruebas , Ecocardiografía/métodos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Función Ventricular Izquierda/fisiología , Volumen Sistólico , Aprendizaje Automático
2.
IEEE Trans Med Imaging ; 36(6): 1221-1230, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28391191

RESUMEN

Echocardiography (echo) is a skilled technical procedure that depends on the experience of the operator. The aim of this paper is to reduce user variability in data acquisition by automatically computing a score of echo quality for operator feedback. To do this, a deep convolutional neural network model, trained on a large set of samples, was developed for scoring apical four-chamber (A4C) echo. In this paper, 6,916 end-systolic echo images were manually studied by an expert cardiologist and were assigned a score between 0 (not acceptable) and 5 (excellent). The images were divided into two independent training-validation and test sets. The network architecture and its parameters were based on the stochastic approach of the particle swarm optimization on the training-validation data. The mean absolute error between the scores from the ultimately trained model and the expert's manual scores was 0.71 ± 0.58. The reported error was comparable to the measured intra-rater reliability. The learned features of the network were visually interpretable and could be mapped to the anatomy of the heart in the A4C echo, giving confidence in the training result. The computation time for the proposed network architecture, running on a graphics processing unit, was less than 10 ms per frame, sufficient for real-time deployment. The proposed approach has the potential to facilitate the widespread use of echo at the point-of-care and enable early and timely diagnosis and treatment. Finally, the approach did not use any specific assumptions about the A4C echo, so it could be generalizable to other standard echo views.


Asunto(s)
Ecocardiografía , Humanos , Redes Neurales de la Computación , Reproducibilidad de los Resultados
3.
IEEE Trans Med Imaging ; 36(1): 40-50, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27455520

RESUMEN

We propose a joint information approach for automatic analysis of 2D echocardiography (echo) data. The approach combines a priori images, their segmentations and patient diagnostic information within a unified framework to determine various clinical parameters, such as cardiac chamber volumes, and cardiac disease labels. The main idea behind the approach is to employ joint Independent Component Analysis of both echo image intensity information and corresponding segmentation labels to generate models that jointly describe the image and label space of echo patients on multiple apical views, instead of independently. These models are then both used for segmentation and volume estimation of cardiac chambers such as the left atrium and for detecting pathological abnormalities such as mitral regurgitation. We validate the approach on a large cohort of echoes obtained from 6,993 studies. We report performance of the proposed approach in estimation of the left-atrium volume and detection of mitral-regurgitation severity. A correlation coefficient of 0.87 was achieved for volume estimation of the left atrium when compared to the clinical report. Moreover, we classified patients that suffer from moderate or severe mitral regurgitation with an average accuracy of 82%.


Asunto(s)
Atrios Cardíacos , Cardiopatías/diagnóstico por imagen , Ecocardiografía , Humanos , Insuficiencia de la Válvula Mitral
4.
J Marital Fam Ther ; 31(1): 89-98, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15739969

RESUMEN

Journal articles published by faculty in Commission on Accreditation for Marriage and Family Therapy Education (COAMFTE) programs from 1998 to 2002 were analyzed to determine patterns regarding the amount and type of research conducted by this group. Fifty-eight percent of the articles were identified as research. Slightly more than 10% of these dealt with clinical processes and outcomes. Forty percent of studies reported a specific source of funding. Twenty-nine percent of research articles used qualitative methods, with percentages rising over the course of time. Results suggest the average number of publications per faculty member was relatively low, particularly for senior faculty. Implications for these findings are discussed.


Asunto(s)
Acreditación , Educación/estadística & datos numéricos , Docentes/estadística & datos numéricos , Terapia Familiar/educación , Terapia Conyugal/educación , Matrimonio/psicología , Edición/estadística & datos numéricos , Investigación/estadística & datos numéricos , Femenino , Humanos , Masculino
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