Rafael Barea Navarro

Automatic measurement of blood flow using artificial vision

A study of the dynamics of filling and emptying of the heart is of great interest for diagnosing cardiac disease. Measuring the rate of blood through the orifices of the heart, using the Doppler method, enables one to estimate cardiac flows and, therefore, cardiac dynamics. A system of artificial vision is described in this article which, starting with the Doppler images, processes the image in order to segment the edges of the orifices of the heart and measure their size. In this way, the instantaneous flow is obtained by means of simple mathematical formulae. Satisfactory results have been obtained which have been assessed by comparing them with accepted techniques (invasive measures).

Color Analysis in Retinography: Glaucoma Image Detection

Glaucoma is a leading cause of permanent blindness. Glaucoma has an initial phase difficult to diagnose, so different measures are used to evaluate it. One of them is a retinography exam which is used to determinate the ratio between the cup and the disc areas, and vein shifting in disc perimeter. A system that allows different measures and calculate them automatically, could be useful to medical community. In this paper it shows a study about papilla and cup segmentation, their ratio and vein shifting ratio and their classification using neural networks. Our system is able to classify the glaucoma automatically with a sensitivity and specifity of 96,77% and 68,2% respectively.

Método simplificado para el análisis no invasivo de la relajación ventricular mediante Doppler continuo en la insuficiencia mitral

Introduccion y objetivos El valor minimo de dP/dT es un parametro de funcion diastolica que puede estimarse de forma no invasiva analizando lacurva de insuficiencia mitral, obtenida por Doppler continuo. Este analisis es complejo y dificulta la aplicacion del metodo. Nuestro objetivo fue validar un metodo simplificado para la estimacion no invasivade dP/dTmin en la insuficiencia mitral. Se calcu la la pendiente de la curva de velocidad de la insuficiencia mitral durante su desaceleracion, en un intervalo entre 3 y 1,5 m/s, que define una diferenciade presion segun Dp = (4v21 – 4v22). Dividiendola por el tiempo necesario para que la curva se decelerede v1 a v2, obtendremos la tasa de descenso de presion, en mmHg/s. Metodos Se provoco insuficiencia mitral en cinco cerdos. Se registro de forma simultanea dP/dT y la curva de la insuficiencia mitral, mediante un cateter con micromanometro en la punta y Doppler continuo, respectivamente. Se calculo la tasa de descenso de presion sobre la curva de la insuficienciamitral. Resultados Se obtuvieron 29 registros simultaneosde dP/dTmin y de la tasa de descenso de presion, con una correlacion con r = 0,62; p Conclusiones Nuestro estudio muestra un metodosimplifica do para la estimacion no invasiva dedP/dT, con aceptable correlacion con las medidas invasivas y adecuada reproductibilidad, caracteris ticasque facilitan su aplicacion practica.

EOG-based wheelchair control

Abstract This chapter presents a literature review of EOG-controlled wheelchairs. The main objective is to develop a control system for guiding the wheelchair using an EOG-based interface. The EOG signal is used to detect eye movements and blinks and these actions are codified as wheelchair control commands. To do this, an electrooculographic eye model has to be designed and implemented. Finally, several techniques and guidance strategies are commented and the main advantages and drawbacks are explained.