Standardized evaluation methodology and reference database for evaluating IVUS image segmentation

This paper describes an evaluation framework that allows a standardized and quantitative comparison of IVUS lumen and media segmentation algorithms. This framework has been introduced at the MICCAI 2011 Computing and Visualization for (Intra)Vascular Imaging (CVII) workshop, comparing the results of eight teams that participated. We describe the available data-base comprising of multi-center, multi-vendor and multi-frequency IVUS datasets, their acquisition, the creation of the reference standard and the evaluation measures. The approaches address segmentation of the lumen, the media, or both borders; semi- or fully-automatic operation; and 2-D vs. 3-D methodology. Three performance measures for quantitative analysis have been proposed. The results of the evaluation indicate that segmentation of the vessel lumen and media is possible with an accuracy that is comparable to manual annotation when semi-automatic methods are used, as well as encouraging results can be obtained also in case of fully-automatic segmentation. The analysis performed in this paper also highlights the challenges in IVUS segmentation that remains to be solved.

El fill de mare diabètica: un experiment de la Natura

Del fill de mare diabètica (FMD) s´ha dit que es tracta d'un autèntic 'experiment de la natura' per tractar-se d'un ésser que al llarg dels seus creixement i desenvolupament intrauterins es relaciona amb un medi ambient diferent al d'una gestació normal. Enfront d'aquesta anomalia, l'embrió primer i el fetus més tard no resten passius, sinó que generen una resposta adaptativa al medi estrany arribant a un altre nivell d'homeostasi però definitivament compensadora de la nova situació. Ara bé, en néixer i 'normalitzar-se' l'ambient, es fa palesa la malaltia...

L'increment demogràfic afecte la salut genètica

Un estudi publicat a 'Science' demostra que l'augment exponencial de la població del planeta també té conseqüències mèdiques, ja que fa créixer el risc de patir malalties rares

A Computer program for estimating population size by the removal method

A BASIC computer program (REMOVAL) was developed to compute in a VAXNMS environment all the calculations of the removal method for population size estimation (catch-effort method for closed populations with constant sampling effort). The program follows the maximum likelihood methodology,checks the failure conditions, applies the appropriate formula, and displays the estimates of population size and catchability, with their standard deviations and coefficients of variation, and two goodness-of-fit statistics with their significance levels. Data of removal experiments for the cyprinodontid fish Aphanius iberus in the Alt Emporda wetlands are used to exemplify the use of the program

Microcalcification evaluation in computer assisted diagnosis for digital mammography

In order to develop applications for z;isual interpretation of medical images, the early detection and evaluation of microcalcifications in digital mammograms is verg important since their presence is oftenassociated with a high incidence of breast cancers. Accurate classification into benign and malignant groups would help improve diagnostic sensitivity as well as reduce the number of unnecessa y biopsies. The challenge here is the selection of the useful features to distinguish benign from malignant micro calcifications. Our purpose in this work is to analyse a microcalcification evaluation method based on a set of shapebased features extracted from the digitised mammography. The segmentation of the microcalcificationsis performed using a fixed-tolerance region growing method to extract boundaries of calcifications with manually selected seed pixels. Taking into account that shapes and sizes of clustered microcalcificationshave been associated with a high risk of carcinoma based on digerent subjective measures, such as whether or not the calcifications are irregular, linear, vermiform, branched, rounded or ring like, our efforts were addressed to obtain a feature set related to the shape. The identification of the pammeters concerning the malignant character of the microcalcifications was performed on a set of 146 mammograms with their real diagnosis known in advance from biopsies. This allowed identifying the following shape-based parameters as the relevant ones: Number of clusters, Number of holes, Area, Feret elongation, Roughness, and Elongation. Further experiments on a set of 70 new mammogmms showed that the performance of the classification scheme is close to the mean performance of three expert radiologists, which allows to consider the proposed method for assisting the diagnosis and encourages to continue the investigation in the senseof adding new features not only related to the shape

A new approach to the classification of mammographic masses and normal breast tissue

A new approach to mammographic mass detection is presented in this paper. Although different algorithms have been proposed for such a task, most of them are application dependent. In contrast, our approach makes use of a kindred topic in computer vision adapted to our particular problem. In this sense, we translate the eigenfaces approach for face detection/classification problems to a mass detection. Two different databases were used to show the robustness of the approach. The first one consisted on a set of 160 regions of interest (RoIs) extracted from the MIAS database, being 40 of them with confirmed masses and the rest normal tissue. The second set of RoIs was extracted from the DDSM database, and contained 196 RoIs containing masses and 392 with normal, but suspicious regions. Initial results demonstrate the feasibility of using such approach with performances comparable to other algorithms, with the advantage of being a more general, simple and cost-effective approach

Modeling and Classifying Breast Tissue Density in Mammograms

We present a new approach to model and classify breast parenchymal tissue. Given a mammogram, first, we will discover the distribution of the different tissue densities in an unsupervised manner, and second, we will use this tissue distribution to perform the classification. We achieve this using a classifier based on local descriptors and probabilistic Latent Semantic Analysis (pLSA), a generative model from the statistical text literature. We studied the influence of different descriptors like texture and SIFT features at the classification stage showing that textons outperform SIFT in all cases. Moreover we demonstrate that pLSA automatically extracts meaningful latent aspects generating a compact tissue representation based on their densities, useful for discriminating on mammogram classification. We show the results of tissue classification over the MIAS and DDSM datasets. We compare our method with approaches that classified these same datasets showing a better performance of our proposal

Implementación de un sistema de almacenamiento y distribución multi-centro de imágenes médicas, mediante software libre

Este trabajo de fin de grado plantea probar la viabilidad de realizar un sistema de almacenamiento y distribución de imágenes médicas, utilizando únicamente software de código abierto, libre distribución o gratuito.

Ensumar la ciutat: anàlisi antropològica de la construcció olfactiva sobre les condicions de salubritat a Catalunya en el segle XIX

Les topografies mèdiques-finals del segle XIX i primeres dècades del segle xx- són informes fets pels metges catalans que volien construir una"geografia mèdica" del país, qüestió fonamental per conèixer l"estat de la salut de la població; avui, aquests informes esdevenen un material de primer ordre per conèixer les condicions de vida en relació amb l"estat de salubritat no solament de les localitats estudiades sinó també de tota una època.

A Multiagent System for Coordinating Ambulances for Emergency Medical Services

To coordinate ambulances for emergency medical services, a multiagent system uses an auction mechanism based on trust. Results of tests using real data show that this system can efficiently assign ambulances to patients, thereby reducing transportation time. Emergency transportation on specialized vehicles is needed when a person's health is in risk of irreparable damage. A patient can't benefit from sophisticated medical treatments and technologies if she or he isn't placed in a proper healthcare center with the appropriate medical team. For example, strokes are neurological emergencies involving a limited amount of time in which treatment measures are effective

Desenvolupament d'interfícies d'usuari i visualització d'imatge mèdica en dispositius mòbils Android

Aquest treball tracta sobre la realització d’una aplicació per a dispositius Android que permeti visualitzar imatges mèdiques. Amb la col·laboració del parc Taulí de Sabadell s’han realitzat tasques de recerca de requeriments com l’elaboració d’una entrevista o la realització d’una maqueta de paper que s’ha sotmès a una avaluació heurística en un procés iteratiu. Finalment, s’ha implementat una aplicació on es poden visualitzar imatges mèdiques, fer accions sobre elles com canviar el color o fer zoom i accedir a informació del pacient.

E=mc2

Quan hom ha d'escriure un text de divulgació científica ha de posar a l'abast de tothom conceptes i idees que inicialment poden semblar difícils. Pera ixò mai s'hi inclouen fórmules matemàtiques. L'única que és permesa en aquests escrits és la famosa equació d'Einstein, que encapçala aquest article. Molt poca gent entén totes les seves implicacions, però és tan senzilla i elegant, i l'hem vista tantes vegades, que ningú la troba estranya [...].

Vols un gen?

En el meu darrer article (AVUI,8 de maig) parlava dels efectes secundaris dels fàrmacs i les teràpies mèdiques, i de les proves que es fan per reduir-ne la incidència, que inclouen assaigs clínics amb voluntaris. Respecte als voluntaris afegia, amb certa ironia, que s'ha de suposar que quan viuen en països del Tercer Món les condicions mèdiques il·legals són iguals que quan els assaigs es fan a Occident, però que malauradament potser en ocasions això era suposar massa [...].