Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
1.
Magn Reson Imaging ; 109: 134-146, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38508290

RESUMO

Accurate and efficient segmenting of vertebral bodies, muscles, and discs is crucial for analyzing various spinal diseases. However, traditional methods are either laborious and time-consuming (manual segmentation) or require extensive training data (fully automatic segmentation). FastCleverSeg, our proposed semi-automatic segmentation approach, addresses those limitations by significantly reducing user interaction while maintaining high accuracy. First, we reduce user interaction by requiring the manual annotation of only two or three slices. Next, we automatically Estimate the Annotation on Intermediary Slices (EANIS) using traditional computer vision/graphics concepts. Finally, our proposed method leverages improved voxel weight balancing to achieve fast and precise volumetric segmentation in the segmentation process. Experimental evaluations on our assembled diverse MRI databases comprising 179 patients (60 male, 119 female), demonstrate a remarkable 25 ms (30 ms standard deviation) processing time and a significant reduction in user interaction compared to existing approaches. Importantly, FastCleverSeg maintains or surpasses the segmentation quality of competing methods, achieving a Dice score of 94%. This invaluable tool empowers physicians to efficiently generate reliable ground truths, expediting the segmentation process and paving the way for future integration with deep learning approaches. In turn, this opens exciting possibilities for future fully automated spine segmentation.


Assuntos
Processamento de Imagem Assistida por Computador , Doenças da Coluna Vertebral , Humanos , Masculino , Feminino , Processamento de Imagem Assistida por Computador/métodos , Coluna Vertebral/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Doenças da Coluna Vertebral/diagnóstico por imagem , Bases de Dados Factuais
2.
Comput Biol Med ; 134: 104489, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34015672

RESUMO

Chronic dermatological ulcers cause great discomfort to patients, and while monitoring the size of wounds over time provides significant clues about the healing evolution and the clinical condition of patients, the lack of practical applications in existing studies impairs users' access to appropriate treatment and diagnosis methods. We propose the UTrack framework to help with the acquisition of photos, the segmentation and measurement of wounds, the storage of photos and symptoms, and the visualization of the evolution of ulcer healing. UTrack-App is a mobile app for the framework, which processes images taken by standard mobile device cameras without specialized equipment and stores all data locally. The user manually delineates the regions of the wound and the measurement object, and the tool uses the proposed UTrack-Seg segmentation method to segment them. UTrack-App also allows users to manually input a unit of measurement (centimeter or inch) in the image to improve the wound area estimation. Experiments show that UTrack-Seg outperforms its state-of-the-art competitors in ulcer segmentation tasks, improving F-Measure by up to 82.5% when compared to superpixel-based approaches and up to 19% when compared to Deep Learning ones. The method is unsupervised, and it semi-automatically segments real-world images with 0.9 of F-Measure, on average. The automatic measurement outperformed the manual process in three out of five different rulers. UTrack-App takes at most 30 s to perform all evaluation steps over high-resolution images, thus being well-suited to analyze ulcers using standard mobile devices.


Assuntos
Aplicativos Móveis , Telemedicina , Atenção à Saúde , Humanos , Úlcera , Cicatrização
3.
Comput Methods Programs Biomed ; 191: 105376, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32066047

RESUMO

BACKGROUND AND OBJECTIVES: Bedridden patients presenting chronic skin ulcers often need to be examined at home. Healthcare professionals follow the evolution of the patients' condition by regularly taking pictures of the wounds, as different aspects of the wound can indicate the healing stages of the ulcer, including depth, location, and size. The manual measurement of the wounds' size is often inaccurate, time-consuming, and can also cause discomfort to the patient. In this work, we propose the Automatic Skin Ulcer Region Assessment ASURA framework to accurately segment the wound and automatically measure its size. METHODS: ASURA uses an encoder/decoder deep neural network to perform the segmentation, which detects the measurement ruler/tape present in the image and estimates its pixel density. RESULTS: Experimental results show that ASURA outperforms the state-of-the-art methods by up to 16% regarding the Dice score, being able to correctly segment the wound with a Dice score higher than 90%. ASURA automatically estimates the pixel density of the images with a relative error of 5%. When using a semi-automatic approach, ASURA was able to estimate the area of the wound in square centimeters with a relative error of 14%. CONCLUSIONS: The results show that ASURA is well-suited for the problem of segmenting and automatically measuring skin ulcers.


Assuntos
Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Úlcera Cutânea/diagnóstico por imagem , Úlcera Cutânea/fisiopatologia , Humanos
4.
Comput Methods Programs Biomed ; 173: 27-34, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31046993

RESUMO

BACKGROUND AND OBJECTIVE: Identifying abnormalities in chest CT scans is an important and challenging task, demanding time and effort from specialists. Different parts of a single lung image may present both normal and abnormal characteristics. Thus, detecting a single lung as healthy (normal) or not is inaccurate. METHODS: In this work we propose dp-BREATH, a method capable of detecting abnormalities in pulmonary tissue regions and directing the specialist's attention to the lung region containing them. It starts by highlighting regions that may indicate pulmonary abnormalities based on the healthy pulmonary tissue behavior using a superpixel-based approach and a heat map visualization. This is achieved by modeling regions of healthy tissue using a statistical model. All regions considered abnormal are modeled and classified according to their probability of containing each of the studied abnormalities. Further, dp-BREATH provides a better recognition of radiological patterns, with the likelihood of a selected lung region to contain abnormalities. RESULTS: We validate the statistical model of healthy and abnormal detection using a representative dataset of chest CT scans. The model has shown almost no overlap between healthy and abnormal regions, and the detection of abnormalities presented precision higher than 86%, for all recall values. Additionally, the fitted models describing pulmonary radiological patterns present precision of up to 87%, with a high separation for three of five radiological patterns. CONCLUSIONS: dp-BREATH's heat map representation and its list of radiological patterns probabilities provided are intuitive methods to assist physicians during diagnosis.


Assuntos
Diagnóstico por Computador/métodos , Pulmão/anormalidades , Pulmão/diagnóstico por imagem , Radiologia/métodos , Tomografia Computadorizada por Raios X , Algoritmos , Simulação por Computador , Humanos , Funções Verossimilhança , Pulmão/patologia , Modelos Estatísticos , Distribuição Normal , Reconhecimento Automatizado de Padrão/métodos , Análise de Componente Principal , Probabilidade , Radiologia/normas , Reprodutibilidade dos Testes , Interface Usuário-Computador
5.
IEEE J Biomed Health Inform ; 23(6): 2220-2229, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30452381

RESUMO

Content-based retrieval still remains one of the main problems with respect to controversies and challenges in digital healthcare over big data. To properly address this problem, there is a need for efficient computational techniques, especially in scenarios involving queries across multiple data repositories. In such scenarios, the common computational approach searches the repositories separately and combines the results into one final response, which slows down the process altogether. In order to improve the performance of queries in that kind of scenario, we present the Domain Index, a new category of index structures intended to efficiently query a data domain across multiple repositories, regardless of the repository to which the data belong. To evaluate our method, we carried out experiments involving content-based queries, namely range and k nearest neighbor (kNN) queries, 1) over real-world data from a public data set of mammograms, as well as 2) over synthetic data to perform scalability evaluations. The results show that images from any repository are seamlessly retrieved, sustaining performance gains of up to 53% in range queries and up to 81% in kNN queries. Regarding scalability, our proposal scaled well as we increased 1) the cardinality of data (up to 59% of gain) and 2) the number of queried repositories (up to 71% of gain). Hence, our method enables significant performance improvements, and should be of most importance for medical data repository maintainers and for physicians' IT support.


Assuntos
Bases de Dados Factuais , Diagnóstico por Imagem , Armazenamento e Recuperação da Informação/métodos , Informática Médica/métodos , Algoritmos , Big Data , Humanos , Mamografia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA