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1.
Sensors (Basel) ; 21(24)2021 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-34960467

RESUMEN

Melanoma is the most lethal form of skin cancer, and develops from mutation of pigment-producing cells. As it becomes malignant, it usually grows in size, changes proportions, and develops an irregular border. We introduce a system for early detection of such changes, which enables whole-body screening, especially useful in patients with atypical mole syndrome. The paper proposes a procedure to build a 3D model of the patient, relate the high-resolution skin images with the model, and orthorectify these images to enable detection of size and shape changes in nevi. The novelty is in the application of image encoding indices and barycentric coordinates of the mesh triangles. The proposed procedure was validated with a set of markers of a specified geometry. The markers were attached to the body of a volunteer and analyzed by the system. The results of quantitative comparison of original and corrected images confirm that the orthorectification allows for more accurate estimation of size and proportions of skin nevi.


Asunto(s)
Melanoma , Nevo , Neoplasias Cutáneas , Cuerpo Humano , Humanos , Piel , Neoplasias Cutáneas/diagnóstico por imagen
2.
BMC Bioinformatics ; 18(1): 526, 2017 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-29183290

RESUMEN

BACKGROUND: Cell-scaffold contact measurements are derived from pairs of co-registered volumetric fluorescent confocal laser scanning microscopy (CLSM) images (z-stacks) of stained cells and three types of scaffolds (i.e., spun coat, large microfiber, and medium microfiber). Our analysis of the acquired terabyte-sized collection is motivated by the need to understand the nature of the shape dimensionality (1D vs 2D vs 3D) of cell-scaffold interactions relevant to tissue engineers that grow cells on biomaterial scaffolds. RESULTS: We designed five statistical and three geometrical contact models, and then down-selected them to one from each category using a validation approach based on physically orthogonal measurements to CLSM. The two selected models were applied to 414 z-stacks with three scaffold types and all contact results were visually verified. A planar geometrical model for the spun coat scaffold type was validated from atomic force microscopy images by computing surface roughness of 52.35 nm ±31.76 nm which was 2 to 8 times smaller than the CLSM resolution. A cylindrical model for fiber scaffolds was validated from multi-view 2D scanning electron microscopy (SEM) images. The fiber scaffold segmentation error was assessed by comparing fiber diameters from SEM and CLSM to be between 0.46% to 3.8% of the SEM reference values. For contact verification, we constructed a web-based visual verification system with 414 pairs of images with cells and their segmentation results, and with 4968 movies with animated cell, scaffold, and contact overlays. Based on visual verification by three experts, we report the accuracy of cell segmentation to be 96.4% with 94.3% precision, and the accuracy of cell-scaffold contact for a statistical model to be 62.6% with 76.7% precision and for a geometrical model to be 93.5% with 87.6% precision. CONCLUSIONS: The novelty of our approach lies in (1) representing cell-scaffold contact sites with statistical intensity and geometrical shape models, (2) designing a methodology for validating 3D geometrical contact models and (3) devising a mechanism for visual verification of hundreds of 3D measurements. The raw and processed data are publicly available from https://isg.nist.gov/deepzoomweb/data/ together with the web -based verification system.


Asunto(s)
Imagenología Tridimensional/métodos , Modelos Biológicos , Andamios del Tejido/química , Algoritmos , Materiales Biocompatibles/química , Células de la Médula Ósea/citología , Humanos , Internet , Masculino , Células Madre Mesenquimatosas/citología , Microscopía de Fuerza Atómica , Microscopía Confocal , Microscopía Electrónica de Rastreo , Interfaz Usuario-Computador , Microtomografía por Rayos X , Adulto Joven
3.
Clin Dermatol ; 42(3): 280-295, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38181888

RESUMEN

The incidence of melanoma is increasing rapidly. This cancer has a good prognosis if detected early. For this reason, various systems of skin lesion image analysis, which support imaging diagnostics of this neoplasm, are developing very dynamically. To detect and recognize neoplastic lesions, such systems use various artificial intelligence (AI) algorithms. This area of computer science applications has recently undergone dynamic development, abounding in several solutions that are effective tools supporting diagnosticians in many medical specialties. In this contribution, a number of applications of different classes of AI algorithms for the detection of this skin melanoma are presented and evaluated. Both classic systems based on the analysis of dermatoscopic images as well as total body systems, enabling the analysis of the patient's whole body to detect moles and pathologic changes, are discussed. These increasingly popular applications that allow the analysis of lesion images using smartphones are also described. The quantitative evaluation of the discussed systems with particular emphasis on the method of validation of the implemented algorithms is presented. The advantages and limitations of AI in the analysis of lesion images are also discussed, and problems requiring a solution for more effective use of AI in dermatology are identified.


Asunto(s)
Algoritmos , Inteligencia Artificial , Dermoscopía , Melanoma , Neoplasias Cutáneas , Humanos , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/patología , Melanoma/diagnóstico , Melanoma/diagnóstico por imagen , Teléfono Inteligente
4.
J Biomed Mater Res A ; 111(1): 106-117, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36194510

RESUMEN

The properties and structure of the cellular microenvironment can influence cell behavior. Sites of cell adhesion to the extracellular matrix (ECM) initiate intracellular signaling that directs cell functions such as proliferation, differentiation, and apoptosis. Electrospun fibers mimic the fibrous nature of native ECM proteins and cell culture in fibers affects cell shape and dimensionality, which can drive specific functions, such as the osteogenic differentiation of primary human bone marrow stromal cells (hBMSCs), by. In order to probe how scaffolds affect cell shape and behavior, cell-fiber contacts were imaged to assess their shape and dimensionality through a novel approach. Fluorescent polymeric fiber scaffolds were made so that they could be imaged by confocal fluorescence microscopy. Fluorescent polymer films were made as a planar control. hBSMCs were cultured on the fluorescent substrates and the cells and substrates were imaged. Two different image analysis approaches, one having geometrical assumptions and the other having statistical assumptions, were used to analyze the 3D structure of cell-scaffold contacts. The cells cultured in scaffolds contacted the fibers in multiple planes over the surface of the cell, while the cells cultured on films had contacts confined to the bottom surface of the cell. Shape metric analysis indicated that cell-fiber contacts had greater dimensionality and greater 3D character than the cell-film contacts. These results suggest that cell adhesion site-initiated signaling could emanate from multiple planes over the cell surface during culture in fibers, as opposed to emanating only from the cell's basal surface during culture on planar surfaces.


Asunto(s)
Células Madre Mesenquimatosas , Osteogénesis , Humanos , Andamios del Tejido/química , Diferenciación Celular , Matriz Extracelular/metabolismo , Células Cultivadas , Ingeniería de Tejidos/métodos , Células de la Médula Ósea
5.
Comput Methods Programs Biomed ; 94(1): 66-76, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18922598

RESUMEN

MaZda, a software package for 2D and 3D image texture analysis is presented. It provides a complete path for quantitative analysis of image textures, including computation of texture features, procedures for feature selection and extraction, algorithms for data classification, various data visualization and image segmentation tools. Initially, MaZda was aimed at analysis of magnetic resonance image textures. However, it revealed its effectiveness in analysis of other types of textured images, including X-ray and camera images. The software was utilized by numerous researchers in diverse applications. It was proven to be an efficient and reliable tool for quantitative image analysis, even in more accurate and objective medical diagnosis. MaZda was also successfully used in food industry to assess food product quality. MaZda can be downloaded for public use from the Institute of Electronics, Technical University of Lodz webpage.


Asunto(s)
Procesamiento de Imagen Asistido por Computador , Programas Informáticos , Algoritmos
6.
Med Image Anal ; 13(2): 312-24, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19157954

RESUMEN

Wireless Capsule Endoscopy (WCE) provides a means to obtain a detailed video of the small intestine. A single session with WCE may produce nearly 8h of video. Its interpretation is tedious task, which requires considerable expertise and is very stressful. The Model of Deformable Rings (MDR) was developed to preprocess WCE video and aid clinicians with its interpretation. The MDR uses a simplified model of a capsule's motion to flexibly match (register) consecutive video frames. Essentially, it computes motion-descriptive characteristics and produces a two-dimensional representation of the gastrointestinal (GI) tract's internal surface - a map. The motion-descriptive characteristics are used to indicate video fragments which exhibit segmentary contractions, peristalsis, refraction phases and areas of capsule retention. Within maps, certain characteristics that indicate areas of bleeding, ulceration and obscuring froth could be recognized. Therefore, the maps allow quick identification of such abnormal areas. The experimental results demonstrate that the number of discovered pathologies and gastrointestinal landmarks increases with the MDR technique.


Asunto(s)
Algoritmos , Inteligencia Artificial , Endoscopía Capsular/métodos , Interpretación de Imagen Asistida por Computador/métodos , Almacenamiento y Recuperación de la Información/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Técnica de Sustracción , Grabación en Video/métodos , Aumento de la Imagen/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
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