This is not a real image:Generative artificial intelligence to enhance radiology education

Radiologists fulfill a critical role in our healthcare system, but their workload has increased substantially over time. Although algorithmic tools have been proposed to support the diagnostic process, the workload is not efficiently decreased in this manner. However, another possibility is to decrease workload in a different area. The main topic of this thesis is concerned with investigating how simulation training can be realized to aid in the image interpretation skills training of the radiology resident. To realize simulated training it is necessary to know (1) how we can create realistic artificial medical images, subsequently (2) How we can control their variety and (3) how we can adjust their difficulty.Firstly, it is shown that artificial medical images can blend in with original ones. For this purpose a GAN model is used to create 2-dimensional artificial medical images. The created artificial images are assessed both quantitatively and qualitatively in terms of their realism. Secondly, to better control the variety of the artificial medical images a diffusion model is used to guide both coarse- and fine-features. The results show that the model was able to adjust fine-feature characteristics of the pathology type according to the feedback of the independent classifier. Thirdly, a method is presented to describe the detection difficulty of an (artificial) medical image using quantitative pathology and image characteristics. Results show that it is possible to describe almost two thirds of the variation in difficulty using these quantitative characteristics and as such describe images as having lower or higher detection difficulty. Finally, the responsible implementation of the medical image simulator to assist in image interpretation skills is investigated. Combining the results of this thesis resulted in a prototype of a 'medical image simulator'. This simulator can take over part of the workload of the supervising radiologists, by providing a means for independent repetitive practice for the resident. The realistic artificial medical images can be varied in terms of their content and their difficulty. This can enable a personalized experience that can enhance training of image interpretation skills and make it more efficient

Registro de patrones de lectura con dispositivos de Eye Tracker de bajo coste y estudio de su aplicación para la recomendación de diagnóstico de patologías

Una de las tecnologías de mayor auge actualmente es la de Eye Tracking o seguimiento ocular. Existen multitud de aplicaciones que hacen uso de dispositivos de seguimiento ocular en ámbitos muy diversos desde marketing, estudios de usabilidad, psicología, medicina, etc. Una gran cantidad de grupos de investigación están utilizando está tecnología para desarrollar y validar su trabajo actual y, empresas tecnológicas de gran renombre están mejorando sus propias aplicaciones e incorporando sistemas de seguimiento ocular a sus dispositivos. En este trabajo se ha abordado el desarrollo de una aplicación de registro de patrones de lectura con un dispositivo de seguimiento ocular de bajo coste, lo que permite que el precio no sea un impedimento para el análisis, validación y uso de los resultados de este trabajo. Tras el estudio de los principales dispositivos de seguimiento ocular, el rastreador ocular elegido corresponde a un modelo de la empresa The Eye Tribe, The Eye Tribe Tracker. Este dispositivo tiene un precio bastante inferior a sus competidores, pero su precisión es lo suficientemente aceptable para la realización de este estudio. La aplicación resultante no solo registra los patrones de lectura del usuario, sino que también incorpora gran cantidad de aspectos de valor añadido, tanto mejoras en la interfaz como mejoras a nivel interno que se comentan a lo largo de esta memoria. La aplicación se ha orientado para su uso en el ámbito médico, en concreto, para la recomendación de diagnóstico de distintas patologías, entre ellas, dislexia, déficit de atención y enfermedades neurodegenerativas. Para ello, se ha realizado un estudio de la importancia de esta tecnología para este fin y los posibles elementos que se deberían incorporar a la aplicación resultante para que pudiera ser utilizada en este contexto. El desarrollo de la aplicación y el estudio de su posible uso en el ámbito médico van acompañado de un procedimiento de validación de la misma con un conjunto reducido de usuarios reales y también, del análisis y evaluación de los resultados obtenidos en los patrones de lectura por estos usuarios. Finalmente, este Trabajo de Fin de Máster termina comentando las principales conclusiones y retos del trabajo planteado, así como, una revisión de posibles trabajos futuros a realizar.Currently, one of the most important technologies is Eye Tracking. There are many applications that make use of eye tracking devices in very different fields from marketing, usability studies, psychology, medicine, etc. A lot of research groups are using this technology to develop and validate their current work and, companies of great reputation are improving their own applications and incorporating eye tracking systems to their main devices. This work has addressed the development of a reading pattern recording application with a low-cost eye tracking device. The use of this device has allowed the price not to be an impediment to the analysis, validation and use of the results of this work. Following the study of the main eye trackers, the chosen eye tracker corresponds to a model of the company The Eye Tribe, The Eye Tribe Tracker. This device has a lower cost than its competitors, but its accuracy is sufficiently acceptable for the execution of this study. The resulting application registers the user's reading patterns and, also, incorporates a lot of aspects that add value to this application, both interface improvements and internal improvements that are discussed throughout this report. The application has been oriented to its use in the medical field, specifically, for the recommendation of diagnosis of different pathologies such as dyslexia, attention deficit and neurodegenerative diseases. For that, a study has been made of the importance of this technology for this objective including the possible elements that should be incorporated into the resulting application so that this application could be used in this context. The development of the application and the study of its possible use in the medical field are accompanied of a validation procedure of the application with a reduced set of real users. It has also made an analysis and evaluation of reading patterns obtained by these users. Finally, this Final Master's Work conclude by commenting on the main conclusions and challenges of the work presented, as well as a review of future work that can be done

Using eye tracking for evaluation of information visualisation in web search interfaces

Search result organization and presentation is an important component of a web search system, and can have a substantial impact on the ability of users to find useful information. Most web search result interfaces include textual information, including for example the document title, URL, and a short query-biased summary of the content. Recent studies have developed various novel visual summaries, aiming to improve the effectiveness of search results. In this thesis, the impact and efficacy of presenting additional visual summaries are investigated through a series of four studies. User interaction with the search results was captured using eye tracking data. In the first study we compare the effectiveness of three publicly available search interfaces for supporting navigational search tasks. The three interfaces varied primarily in the proportion of visual versus textual cues that were used to display a search result. Our analysis shows that users' search completion time varies greatly among interfaces, and an appropriate combination of textual and visual information leads to the shortest search completion time and the least number of wrong answers. Another outcome of this experiment is the identification of factors that should be accounted for in subsequent, more controlled, experiments with visual summaries, including the size of the visual summaries and interface design. An understanding of the features and limitations of the eye tracker, particularly for IR studies, was also obtained. To obtain a richer understanding of a user's information seeking strategies and the impact of presenting additional visual summaries, five interfaces were designed: text-only, thumbnail, image, tag and visual snippet. In the second study, fifty participants carried out searches on five informational topics, using the five different interfaces. Findings show that visual summaries significantly impact on the behaviour of users, but not on their performance when predicting the relevance of answer resources. In the third study, fifty participants carried out five navigational topics using the five different interfaces. The results show that apart from the salient image interface, users perform statistically significantly better in terms of time required and effort required to answer given navigational search topics when additional visual summaries are presented. The fourth study was conducted with both navigational and informational topics, for a more detailed comparison between the best-performing interfaces identified in the previous studies: salient images for informational searches, and thumbnails for navigational searches. The findings confirm our previous results. Overall, the salient image interface can significantly increase user performance with informational topics, while thumbnails can help users to predict relevant answers, in a significantly shorter time, with navigational search topics