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1.
Comput Med Imaging Graph ; 108: 102283, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37562136

RESUMO

Strain represents the quantification of regional tissue deformation within a given area. Myocardial strain has demonstrated considerable utility as an indicator for the assessment of cardiac function. Notably, it exhibits greater sensitivity in detecting subtle myocardial abnormalities compared to conventional cardiac function indices, like left ventricle ejection fraction (LVEF). Nonetheless, the estimation of strain poses considerable challenges due to the necessity for precise tracking of myocardial motion throughout the complete cardiac cycle. This study introduces a novel deep learning-based pipeline, designed to automatically and accurately estimate myocardial strain from three-dimensional (3D) cine-MR images. Consequently, our investigation presents a comprehensive pipeline for the precise quantification of local and global myocardial strain. This pipeline incorporates a supervised Convolutional Neural Network (CNN) for accurate segmentation of the cardiac muscle and an unsupervised CNN for robust left ventricle motion tracking, enabling the estimation of strain in both artificial phantoms and real cine-MR images. Our investigation involved a comprehensive comparison of our findings with those obtained from two commonly utilized commercial software in this field. This analysis encompassed the examination of both intra- and inter-user variability. The proposed pipeline exhibited demonstrable reliability and reduced divergence levels when compared to alternative systems. Additionally, our approach is entirely independent of previous user data, effectively eliminating any potential user bias that could influence the strain analyses.


Assuntos
Aprendizado Profundo , Reprodutibilidade dos Testes , Imagem Cinética por Ressonância Magnética/métodos , Coração/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2022: 545-548, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-36086491

RESUMO

Accurate quantification of myocardium strain in magnetic resonance images is important to correctly diagnose and monitor cardiac diseases. Currently, available methods to estimate motion are based on tracking brightness pattern differences between images. In cine-MR images, the myocardium interior presents an inhered homogeneity, which reduces the accuracy in estimated motion, and consequently strain. Neural networks have recently been shown to be an important tool for a variety of applications, including motion estimation. In this work, we investigate the feasibility of quantifying myocardium strain in cardiac resonance synthetic images using motion generated by a compact and powerful network called Pyramid, Warping, and Cost Volume (PWC). Using the motion generated by the neural network, the radial myocardium strain obtained presents a mean average error of 12.30% +- 6.50%, and in the circumferential direction 1.20% +-0.61 %, better than the two classical methods evaluated. Clinical Relevance- This work demonstrates the feasibility of estimating myocardium strain using motion estimated by a convolutional neural network.


Assuntos
Coração , Miocárdio , Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Movimento (Física) , Miocárdio/patologia , Redes Neurais de Computação
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1203-1206, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018203

RESUMO

Cardiovascular disease is one of the major health problems worldwide. In clinical practice, cardiac magnetic resonance imaging (CMR) is considered the gold-standard imaging modality for the evaluation of the function and structure of the left ventricle (LV). More recently, deep learning methods have been used to segment LV with impressive results. On the other hand, this kind of approach is prone to overfit the training data, and it does not generalize well between different data acquisition centers, thus creating constraints to the use in daily routines. In this paper, we explore methods to improve the generalization in the segmentation performed by a convolutional neural network. We applied a U-net based architecture and compared two different pre-processing methods to improve uniformity in the image contrast between five cross-dataset training and testing. Overall, we were able to perform the segmentation of the left ventricle using multiple cross-dataset combinations of train and test, with a mean endocardium dice score of 0.82.Clinical Relevance- This work improves the result between the cross-dataset evaluation of the left ventricle segmentation, reducing the constraints for daily clinical adoption of a fully-automatic segmentation method.


Assuntos
Aprendizado Profundo , Ventrículos do Coração , Algoritmos , Coração , Ventrículos do Coração/diagnóstico por imagem , Imageamento por Ressonância Magnética
4.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 1221-1224, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018207

RESUMO

Cardiovascular magnetic resonance imaging (CMRI) is one of the most accurate non-invasive modalities for evaluation of cardiac function, especially the left ventricle (LV). In this modality, the manual or semi-automatic delineation of LV by experts is currently the standard clinical practice for chambers segmentation. Despite these efforts, global quantification of LV remains a challenge. In this work, a combination of two convolutional neural network (CNN) architectures for quantitative evaluation of the LV is described, which estimates the cavity and the myocardium areas, endocardial cavity dimensions in three directions, and the myocardium regional wall thickness in six radial directions. The method was validated in CMRI exams of 56 patients (LVQuan19 dataset) and evaluated by metrics Dice Index, Mean Absolute Error, and Correlation with superior performance compared to the state-of-the-art methods. The combination of the CNN architectures provided a simpler yet fully automated approach, requiring no specialist interaction.Clinical Relevance- With the proposed method, it is possible to perform automatically the full quantification of regional clinically relevant parameters of the left ventricle in short-axis CMRI images with superior performance compared to state-of-the-art methods.


Assuntos
Imagem Cinética por Ressonância Magnética , Redes Neurais de Computação , Endocárdio , Ventrículos do Coração/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética
5.
J. health inform ; 8(supl.I): 203-210, 2016. ilus, tab
Artigo em Português | LILACS | ID: biblio-906245

RESUMO

OBJETIVOS: desenvolver solução para integração de monitores de beira de leito ao Sistema de Informações Hospitalares (SIH). MÉTODOS: Desenvolvimento e implementação de troca de mensagens no padrão Health Level 7, Admit Discharge Transfer (ADT) e Observation (OBX), utilizando a biblioteca HAPI, para cadastro do paciente e coletados parâmetros de monitoramento. Criação de base de dados para seleção e armazenamento dos parâmetros desejados. RESULTADOS: cadastro integrado com o SIH e captura em banco de dados dos parâmetros dos monitores de beira de leito além de interface de teste para visualização dos dados. CONCLUSÃO: Desenvolvido e implementado um sistema para a integração com monitores beira de leito, permitindo uma visão mais abrangente dos dados dos pacientes.


OBJECTIVES: develop solution for integration of bedside monitors to the Hospital Information System (HIS). METHODS: Development and implementation of the exchange of messages using the standard Health Level 7, Admit Discharge Transfer (ADT) and Observation (OBX), using the HAPI library in order to register the patient and to collect parameters from the monitors. It was also created a database in order to support the selection and storage of the desired parameters. RESULTS: registration integrated with HIS and saving of bedside monitors' parameters in database plus test interface for data visualization. CONCLUSION: Developed and implemented a system to integrate with bedside monitors, allowing a more comprehensive view of patient data.


Assuntos
Humanos , Integração de Sistemas , Monitoramento Ambiental , Nível Sete de Saúde , Congressos como Assunto
6.
IEEE Trans Inf Technol Biomed ; 11(1): 17-24, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17249400

RESUMO

Patients usually get medical assistance in several clinics and hospitals during their lifetime, archiving vital information in a dispersed way. Clearly, a proper patient care should take into account that information in order to check for incompatibilities, avoid unnecessary exams, and get relevant clinical history. The Heart Institute (InCor) of São Paulo, Brazil, has been committed to the goal of integrating all exams and clinical information within the institution and other hospitals. Since InCor is one of the six institutes of the University of São Paulo Medical School and each institute has its own information system, exchanging information among the institutes is also a very important aspect that has been considered. In the last few years, a system for transmission, archiving, retrieval, processing, and visualization of medical images integrated with a hospital information system has been successfully created and constitutes the InCor's electronic patient record (EPR). This work describes the experience in the effort to develop a functional and comprehensive EPR, which includes laboratory exams, images (static, dynamic, and three dimensional), clinical reports, documents, and even real-time vital signals. A security policy based on a contextual role-based access control model was implemented to regulate user's access to EPR. Currently, more than 10 TB of digital imaging and communications in medicine (DICOM) images have been stored using the proposed architecture and the EPR stores daily more than 11 GB of integrated data. The proposed storage subsystem allows 6 months of visibility for rapid retrieval and more than two years for automatic retrieval using a jukebox. This paper addresses also a prototype for the integration of distributed and heterogeneous EPR.


Assuntos
Cardiologia/tendências , Sistemas de Gerenciamento de Base de Dados/tendências , Sistemas de Apoio a Decisões Clínicas/tendências , Diagnóstico por Imagem/tendências , Armazenamento e Recuperação da Informação/tendências , Sistemas Computadorizados de Registros Médicos/tendências , Sistemas de Informação em Radiologia/tendências , Brasil , Atenção à Saúde/tendências
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