62 research outputs found

    Robust GPU-based Virtual Reality Simulation of Radio Frequency Ablations for Various Needle Geometries and Locations

    Full text link
    Purpose: Radio-frequency ablations play an important role in the therapy of malignant liver lesions. The navigation of a needle to the lesion poses a challenge for both the trainees and intervening physicians. Methods: This publication presents a new GPU-based, accurate method for the simulation of radio-frequency ablations for lesions at the needle tip in general and for an existing visuo-haptic 4D VR simulator. The method is implemented real-time capable with Nvidia CUDA. Results: It performs better than a literature method concerning the theoretical characteristic of monotonic convergence of the bioheat PDE and a in vitro gold standard with significant improvements (p < 0.05) in terms of Pearson correlations. It shows no failure modes or theoretically inconsistent individual simulation results after the initial phase of 10 seconds. On the Nvidia 1080 Ti GPU it achieves a very high frame rendering performance of >480 Hz. Conclusion: Our method provides a more robust and safer real-time ablation planning and intraoperative guidance technique, especially avoiding the over-estimation of the ablated tissue death zone, which is risky for the patient in terms of tumor recurrence. Future in vitro measurements and optimization shall further improve the conservative estimate.Comment: 18 pages, 14 figures, 1 table, 2 algorithms, 2 movie

    Robotic Ultrasound Imaging: State-of-the-Art and Future Perspectives

    Full text link
    Ultrasound (US) is one of the most widely used modalities for clinical intervention and diagnosis due to the merits of providing non-invasive, radiation-free, and real-time images. However, free-hand US examinations are highly operator-dependent. Robotic US System (RUSS) aims at overcoming this shortcoming by offering reproducibility, while also aiming at improving dexterity, and intelligent anatomy and disease-aware imaging. In addition to enhancing diagnostic outcomes, RUSS also holds the potential to provide medical interventions for populations suffering from the shortage of experienced sonographers. In this paper, we categorize RUSS as teleoperated or autonomous. Regarding teleoperated RUSS, we summarize their technical developments, and clinical evaluations, respectively. This survey then focuses on the review of recent work on autonomous robotic US imaging. We demonstrate that machine learning and artificial intelligence present the key techniques, which enable intelligent patient and process-specific, motion and deformation-aware robotic image acquisition. We also show that the research on artificial intelligence for autonomous RUSS has directed the research community toward understanding and modeling expert sonographers' semantic reasoning and action. Here, we call this process, the recovery of the "language of sonography". This side result of research on autonomous robotic US acquisitions could be considered as valuable and essential as the progress made in the robotic US examination itself. This article will provide both engineers and clinicians with a comprehensive understanding of RUSS by surveying underlying techniques.Comment: Accepted by Medical Image Analysi

    Using brain-computer interaction and multimodal virtual-reality for augmenting stroke neurorehabilitation

    Get PDF
    Every year millions of people suffer from stroke resulting to initial paralysis, slow motor recovery and chronic conditions that require continuous reha bilitation and therapy. The increasing socio-economical and psychological impact of stroke makes it necessary to find new approaches to minimize its sequels, as well as novel tools for effective, low cost and personalized reha bilitation. The integration of current ICT approaches and Virtual Reality (VR) training (based on exercise therapies) has shown significant improve ments. Moreover, recent studies have shown that through mental practice and neurofeedback the task performance is improved. To date, detailed in formation on which neurofeedback strategies lead to successful functional recovery is not available while very little is known about how to optimally utilize neurofeedback paradigms in stroke rehabilitation. Based on the cur rent limitations, the target of this project is to investigate and develop a novel upper-limb rehabilitation system with the use of novel ICT technolo gies including Brain-Computer Interfaces (BCI’s), and VR systems. Here, through a set of studies, we illustrate the design of the RehabNet frame work and its focus on integrative motor and cognitive therapy based on VR scenarios. Moreover, we broadened the inclusion criteria for low mobility pa tients, through the development of neurofeedback tools with the utilization of Brain-Computer Interfaces while investigating the effects of a brain-to-VR interaction.Todos os anos, milho˜es de pessoas sofrem de AVC, resultando em paral isia inicial, recupera¸ca˜o motora lenta e condic¸˜oes cr´onicas que requerem re abilita¸ca˜o e terapia cont´ınuas. O impacto socioecon´omico e psicol´ogico do AVC torna premente encontrar novas abordagens para minimizar as seque las decorrentes, bem como desenvolver ferramentas de reabilita¸ca˜o, efetivas, de baixo custo e personalizadas. A integra¸c˜ao das atuais abordagens das Tecnologias da Informa¸ca˜o e da Comunica¸ca˜o (TIC) e treino com Realidade Virtual (RV), com base em terapias por exerc´ıcios, tem mostrado melhorias significativas. Estudos recentes mostram, ainda, que a performance nas tare fas ´e melhorada atrav´es da pra´tica mental e do neurofeedback. At´e a` data, na˜o existem informac¸˜oes detalhadas sobre quais as estrat´egias de neurofeed back que levam a uma recupera¸ca˜o funcional bem-sucedida. De igual modo, pouco se sabe acerca de como utilizar, de forma otimizada, o paradigma de neurofeedback na recupera¸c˜ao de AVC. Face a tal, o objetivo deste projeto ´e investigar e desenvolver um novo sistema de reabilita¸ca˜o de membros supe riores, recorrendo ao uso de novas TIC, incluindo sistemas como a Interface C´erebro-Computador (ICC) e RV. Atrav´es de um conjunto de estudos, ilus tramos o design do framework RehabNet e o seu foco numa terapia motora e cognitiva, integrativa, baseada em cen´arios de RV. Adicionalmente, ampli amos os crit´erios de inclus˜ao para pacientes com baixa mobilidade, atrav´es do desenvolvimento de ferramentas de neurofeedback com a utilizac¸˜ao de ICC, ao mesmo que investigando os efeitos de uma interac¸˜ao c´erebro-para-RV

    Trends and features of virtual reality: a literature review between 2017 and 2018

    Get PDF
    Virtual Reality has greatly evolved since the 1960´s to the present. It has been implemented in multiple research and knowledge areas, the most recognized being the entertainment industry. In order to establish the state of Virtual Reality and get an idea of its prospects, 537 scientific documents have been reviewed, applying search criteria, more specifically, Virtual Reality applied to education. A bibliometric analysis was realized based on summarizing each document, as well as its keywords and trends, then proceeding to categorize each one, according to the field of application. It was found that Virtual Reality is having relevance in medicine and training area, due to the ability to simulate difficult situations and above all, specific conditions raised by instructors. The future of Virtual Reality as a tool to train professionals in multiples areas is promising.La realidad virtual ha tenido una gran evolución desde la década de 1960 hasta el día de hoy. Se ha implementado en múltiples áreas, tanto de la investigación como del conocimiento, siendo más reconocida en la industria del entretenimiento. Con el propósito de establecer el estado de la realidad virtual y obtener una idea de su futuro, 537 documentos científicos han sido revisados aplicando criterios de búsqueda específicos, como realidad virtual aplicada a la educación. Un análisis bibliométrico fue realizado, teniendo como base un resumen y descripción de cada artículo, así como sus palabras claves y tendencias, procediendo a categorizar cada documento de acuerdo con su campo de aplicación. Se encontró que la realidad virtual tiene una gran relevancia en la medicina, industria militar y en el entrenamiento de personas, debido a su capacidad de simular situaciones difíciles y, sobre todo, condiciones específicas requeridas por instructores. El futuro de la realidad virtual como herramienta de entrenamiento para los profesionales de múltiples áreas es promisori

    Tendencias y características de la realidad virtual: Una revisión de la literatura

    Get PDF
    Virtual Reality has greatly evolved between 1940s and 1990s. Since then, it has been implemented in multiple research and knowledge areas, the most recognized being the entertainment industry. In order to establish the state of Virtual Reality and get an idea of its prospects, 537 scientific documents have been reviewed, applying search criteria, more specifically, Virtual Reality applied to education. A bibliometric analysis was realized based on summarizing each document, as well as its keywords and trends, then proceeding to categorize each one, according to the field of application. It was found that Virtual Reality is having relevance in medicine and training area, due to the ability to simulate difficult situations and above all, specific conditions raised by instructors. The future of Virtual Reality as a tool to train professionals in multiples areas is promising.La realidad virtual ha tenido una gran avance entre la década 1940 y 1990. Desde entonces, se ha implementado en múltiples áreas, tanto de la investigación como del conocimiento, siendo más reconocida en la industria del entretenimiento. Con el propósito de establecer el estado de la realidad virtual y obtener una idea de su futuro, 537 documentos científicos han sido revisados aplicando criterios de búsqueda específicos, como realidad virtual aplicada a la educación. Un análisis bibliométrico fue realizado, teniendo como base un resumen y descripción de cada artículo, así como sus palabras claves y tendencias, procediendo a categorizar cada documento de acuerdo con su campo de aplicación. Se encontró que la realidad virtual tiene una gran relevancia en la medicina y en el entrenamiento de personas, debido a su capacidad de simular situaciones difíciles y, sobre todo, condiciones específicas requeridas por instructores. El futuro de la realidad virtual como herramienta de entrenamiento para los profesionales de múltiples áreas es promisori

    Haptics Rendering and Applications

    Get PDF
    There has been significant progress in haptic technologies but the incorporation of haptics into virtual environments is still in its infancy. A wide range of the new society's human activities including communication, education, art, entertainment, commerce and science would forever change if we learned how to capture, manipulate and reproduce haptic sensory stimuli that are nearly indistinguishable from reality. For the field to move forward, many commercial and technological barriers need to be overcome. By rendering how objects feel through haptic technology, we communicate information that might reflect a desire to speak a physically- based language that has never been explored before. Due to constant improvement in haptics technology and increasing levels of research into and development of haptics-related algorithms, protocols and devices, there is a belief that haptics technology has a promising future
    corecore