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1.
Phys Med Biol ; 69(12)2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38815610

RESUMEN

Objective. The distribution of hypoxia within tissues plays a critical role in tumor diagnosis and prognosis. Recognizing the significance of tumor oxygenation and hypoxia gradients, we introduce mathematical frameworks grounded in mechanistic modeling approaches for their quantitative assessment within a tumor microenvironment. By utilizing known blood vasculature, we aim to predict hypoxia levels across different tumor types.Approach. Our approach offers a computational method to measure and predict hypoxia using known blood vasculature. By formulating a reaction-diffusion model for oxygen distribution, we derive the corresponding hypoxia profile.Main results. The framework successfully replicates observed inter- and intra-tumor heterogeneity in experimentally obtained hypoxia profiles across various tumor types (breast, ovarian, pancreatic). Additionally, we propose a data-driven method to deduce partial differential equation models with spatially dependent parameters, which allows us to comprehend the variability of hypoxia profiles within tissues. The versatility of our framework lies in capturing diverse and dynamic behaviors of tumor oxygenation, as well as categorizing states of vascularization based on the dynamics of oxygen molecules, as identified by the model parameters.Significance. The proposed data-informed mechanistic method quantitatively assesses hypoxia in the tumor microenvironment by integrating diverse histopathological data and making predictions across different types of data. The framework provides valuable insights from both modeling and biological perspectives, advancing our comprehension of spatio-temporal dynamics of tumor oxygenation.


Asunto(s)
Modelos Biológicos , Oxígeno , Microambiente Tumoral , Oxígeno/metabolismo , Humanos , Hipoxia Tumoral , Neoplasias/metabolismo , Neoplasias/fisiopatología , Neoplasias/irrigación sanguínea , Hipoxia de la Célula , Hipoxia/metabolismo , Hipoxia/fisiopatología
2.
Diagn Interv Imaging ; 98(5): 423-428, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28330587

RESUMEN

PURPOSE: The purpose of this study was to determine the accuracy of manual semi-automated and volumetric measurements to assess prostate cancer volume on multiparametric magnetic resonance imaging (MP-MRI) using whole-mount histopathology for validation. MATERIALS AND METHODS: We evaluated 30 consecutive men (median age, 65.7 years; interquartile range [IQR], 61.5-70.9 years) with a median prostatic specific antigen of 8.5ng/dL (IQR, 5.5-10.5ng/dL), who underwent MP-MRI before radical prostatectomy. Index tumor volume was determined prospectively and independently on the basis of MRI and whole-mount section volumetric assessment using the maximum histologic diameter (MHD) and the histologic volume (HV). The MRI index tumor volume was determined by two independent radiologists using a single measurement of the maximum tumor dimension (MTD), a simplified MR ellipsoid volume (MREV) calculation and a MR region of interest volume (MROV) segmentation displayed by a commercially available OsiriX®. MTD was compared to MHD, whereas MREV and MROV were compared to HV. RESULTS: Thirty index lesions (median HV, 1.514 cm3; IQR, 0.05-3.780 cm3) were analyzed. The MREV, MROV and HD were significantly correlated with each other (r>0.5). Inter-observer agreement for measurements was good for each method (r>0.780). The MTD was the best predictor of maximum histologic diameter (r=0.980 and 0.791) and had an excellent inter-variability correlation (P<0.0001). CONCLUSION: Prostate cancer histologic volume can be assessed using MREV or MROV with a good accuracy and low inter-observer variability. MTD has the lowest inter-observer variability and provides best degrees of correlation with MHD. MTD should be used on MRI for selecting and following patients for active surveillance and staging before focal treatment of prostate cancer.


Asunto(s)
Imagen por Resonancia Magnética , Próstata/diagnóstico por imagen , Próstata/patología , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Carga Tumoral , Anciano , Automatización , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos
3.
Comput Med Imaging Graph ; 42: 2-15, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25442055

RESUMEN

This study concerns a novel symbolic cognitive vision framework emerged from the Cognitive Microscopy (MICO(1)) initiative. MICO aims at supporting the evolution towards digital pathology, by studying cognitive clinical-compliant protocols involving routine virtual microscopy. We instantiate this paradigm in the case of mitotic count as a component of breast cancer grading in histopathology. The key concept of our approach is the role of the semantics as driver of the whole slide image analysis protocol. All the decisions being taken into a semantic and formal world, MICO represents a knowledge-driven platform for digital histopathology. Therefore, the core of this initiative is the knowledge representation and the reasoning. Pathologists' knowledge and strategies are used to efficiently guide image analysis algorithms. In this sense, hard-coded knowledge, semantic and usability gaps are to be reduced by a leading, active role of reasoning and of semantic approaches. Integrating ontologies and reasoning in confluence with modular imaging algorithms, allows the emergence of new clinical-compliant protocols for digital pathology. This represents a promising way to solve decision reproducibility and traceability issues in digital histopathology, while increasing the flexibility of the platform and pathologists' acceptance, the one always having the legal responsibility in the diagnosis process. The proposed protocols open the way to increasingly reliable cancer assessment (i.e. multiple slides per sample analysis), quantifiable and traceable second opinion for cancer grading, and modern capabilities for cancer research support in histopathology (i.e. content and context-based indexing and retrieval). Last, but not least, the generic approach introduced here is applicable for number of additional challenges, related to molecular imaging and, in general, to high-content image exploration.


Asunto(s)
Neoplasias de la Mama/patología , Núcleo Celular/patología , Interpretación de Imagen Asistida por Computador/métodos , Aprendizaje Automático , Microscopía/métodos , Mitosis , Algoritmos , Femenino , Técnicas Histológicas/métodos , Humanos , Aumento de la Imagen/métodos , Clasificación del Tumor , Reconocimiento de Normas Patrones Automatizadas/métodos , Reproducibilidad de los Resultados , Semántica , Sensibilidad y Especificidad , Procesamiento de Señales Asistido por Computador , Programas Informáticos , Interfaz Usuario-Computador
4.
Comput Med Imaging Graph ; 38(5): 390-402, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24831181

RESUMEN

Breast cancer is the second most frequent cancer. The reference process for breast cancer prognosis is Nottingham grading system. According to this system, mitosis detection is one of the three important criteria required for grading process and quantifying the locality and prognosis of a tumor. Multispectral imaging, as relatively new to the field of histopathology, has the advantage, over traditional RGB imaging, to capture spectrally resolved information at specific frequencies, across the electromagnetic spectrum. This study aims at evaluating the accuracy of mitosis detection on histopathological multispectral images. The proposed framework includes: selection of spectral bands and focal planes, detection of candidate mitotic regions and computation of morphological and multispectral statistical features. A state-of-the-art of the methods for mitosis classification is also provided. This framework has been evaluated on MITOS multispectral dataset and achieved higher detection rate (67.35%) and F-Measure (63.74%) than the best MITOS contest results (Roux et al., 2013). Our results indicate that the selected multispectral bands have more discriminant information than a single spectral band or all spectral bands for mitotic figures, validating the interest of using multispectral images to improve the quality of the diagnostic in histopathology.


Asunto(s)
Neoplasias de la Mama/fisiopatología , Mitosis , Reconocimiento de Normas Patrones Automatizadas/métodos , Algoritmos , Neoplasias de la Mama/patología , Diagnóstico por Imagen/métodos , Femenino , Humanos
5.
Gerontology ; 58(6): 554-63, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22677914

RESUMEN

Our research was motivated by the growing aging population worldwide and the need to concentrate research efforts on a specific target group; it focuses on elderly persons with physical and cognitive deficiencies. The primary goal is to enable persons with mild dementia to maximize their physical and mental functions through assistive technologies in order to be able to continue to participate in social networks and lead independent and purposeful lives. Persons with mild dementia usually have problems in performing activities of daily living due to episodic memory decline. These can include simple activities, such as bathing, changing clothes and preparing meals. Through extended field test trials involving end users, we have demonstrated that assistive technology that provides timely prompts, alarms and reminders can enable them to preserve their abilities and improve their quality of life. Understanding the user context, especially when targeting demented individuals, and providing the required personalized assistive services is the objective of our research work. Finding the appropriate user interface to interact with the provided services is often a barrier. Thus, we have adopted the approach of a multimodal interactive system with the living environment including a TV set, iPad-like tablets, sensors/actuators, and wireless speakers connected to a reasoning engine that is able to consider the complexity of the users' profile defined by his/her cognitive abilities. In this paper we will mainly focus on the interaction level with the system as well as on the validation stages performed to meet the users' requirements. This is the result of several years' work since 2006 in the frame of two projects (IST-FP6 COGKNOW European completed project and AMUPADH ongoing project in Singapore).


Asunto(s)
Disfunción Cognitiva/terapia , Demencia/terapia , Vida Independiente/tendencias , Anciano , Envejecimiento/psicología , Cuidadores , Disfunción Cognitiva/psicología , Demencia/psicología , Humanos , Dispositivos de Autoayuda , Interfaz Usuario-Computador
6.
Artículo en Inglés | MEDLINE | ID: mdl-19163607

RESUMEN

In this paper we study automatic classification of working areas in peripheral blood smears using image analysis and recognition methods. Such automatic classification can provide objective and reproducible quality control for the evaluation of smears and smear maker devices. However, research in this filed has drawn little attention. Existing methods either can not differentiate correctly different cell distributions or rely on the extraction of the central pallor zones in cells for counting, which are not always observable. In contrast, we do not rely on the pallor zone extraction thus on more general basis. We introduce two generic parameters to measure the goodness of working areas, one for the degree of overlap, and the other for the spatial occupancy. We also propose a cascading classification network for the classification of different areas. The effectiveness of our method has been tested on over 150 labeled images acquired from three malaria-infected Giemsa-stained blood smears using an oil immersion 100 x objective.


Asunto(s)
Colorantes Azulados/farmacología , Células Sanguíneas/clasificación , Células Sanguíneas/citología , Citodiagnóstico/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Algoritmos , Automatización , Procesamiento Automatizado de Datos , Humanos , Modelos Estadísticos , Reconocimiento de Normas Patrones Automatizadas , Reproducibilidad de los Resultados
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