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At least 793 records · Page 44Linked to original sources

PubMed1997

Virtual reality therapy of multiple sclerosis and spinal cord injury: design consideration for a haptic-visual interface.

Multiple sclerosis and spinal cord injury patients can benefit by interaction with a haptic-visual system to increase the accuracy of movements in cases of spasticity, cerebellar tremor, and weakness. The device would apply a counterforce to constrain the upper extremity to a force corridor, a region of force/velocity space, designed to increase movement accuracy. Execution of movements with counterforce assistance under certain conditions improves accuracy and should enable patients to develop enhanced strategies for dealing with the movement disorders resulting from their neurologic deficits. Generation of appropriate force feedback requires dynamic adjustment of feedback plant characteristics and integration of visuospatial information in a virtual reality environment. Sensory augmentation, including compensation for visual and proprioceptive loss, can theoretically also be achieved with this approach. The underlying principles in the development of such a system are presented.

Computer Graphics↗

PubMed1998

Design of a 3D workbench interface for training in dental implantology.

The recent technological advances in the area of image processing and interactive computer graphics have lead to many sophisticated systems which support clinical experts in diagnosis and treatment planning tasks. In dentistry, the treatment with implants becomes more and more important. Although in the near future there will be increased demand for dentists who are trained in dental implantology, little effort has been made to introduce technologically new teaching methods into the curriculum of dentists. This paper describes the design of a virtual implant treatment planning system which is based on the concept of a three-dimensional horizontal display. The system is utilizing different VR and multimedia techniques to achieve a highly interactive virtual workbench environment which is suited for class-room experimental education in dental implantology.

Computer-Assisted Instruction↗

PubMed2001

How to invest in social capital.

Business runs better when people within a company have close ties and trust one another. But the relationships that make organizations work effectively are under assault for several reasons. Building such "social capital" is difficult in volatile times. Disruptive technologies spawn new markets daily, and organizations respond with constantly changing structures. The problem is worsened by the virtuality of many of today's workplaces, with employees working off-site or on their own. What's more, few managers know how to invest in such social capital. The authors describe how managers can help their organizations thrive by making effective investments in social capital. For instance, companies that value social capital demonstrate a commitment to retention as a way of limiting workplace volatility. The authors cite SAS's extensive efforts to signal to employees that it sees them as human beings, not just workers. Managers can build trust by showing trust themselves, as well as by rewarding trust and sending clear signals to employees. They can foster cooperation by giving employees a common sense of purpose through good strategic communication and inspirational leadership. Johnson & Johnson's well-known credo, which says the company's first responsibility is to the people who use its products, has helped the company in time of adversity, as in 1982 when cyanide in Tylenol capsules killed seven people. Other methods of fostering cooperation include rewarding the behavior with cash and establishing rules that get people into the habit of cooperating. Social capital, once a given in organizations, is now rare and endangered. By investing in it, companies will be better positioned to seize the opportunities in today's volatile, virtual business environment.

Commerce↗

PubMed2002

An innovative method for preparation for rural practice: the high school rural scholars program.

Recent studies have shown that the most effective strategy to increase the number of practicing rural physicians is to admit more students with affinity for rural practice to medical school. A significant limitation of this strategy is the generally lower scores made on standardized tests by those from smaller high schools in rural areas. Although once admitted these students perform on a par with their urban counterparts, admission remains an obstacle for many. This report summarizes the second year of an innovative program that placed rising high school seniors in shadowing opportunities in their home towns while providing preparation for the ACT exam in a virtual classroom environment. Results show that the 20 students involved increased their knowledge of the strengths and weaknesses of health care in their towns as well as their understanding of how various health professionals function. The ACT composite score increased by 1.2 points, to 23. The reading and science subscores showed the largest increase. Although labor-intensive for the coordinators, the program was successful in meeting the stated goals.

Adolescent↗

PubMed2003

Multisensory integration during motor planning.

When planning goal-directed reaches, subjects must estimate the position of the arm by integrating visual and proprioceptive signals from the sensory periphery. These integrated position estimates are required at two stages of motor planning: first to determine the desired movement vector, and second to transform the movement vector into a joint-based motor command. We quantified the contributions of each sensory modality to the position estimate formed at each planning stage. Subjects made reaches in a virtual reality environment in which vision and proprioception were dissociated by shifting the location of visual feedback. The relative weighting of vision and proprioception at each stage was then determined using computational models of feedforward motor control. We found that the position estimate used for movement vector planning relies mostly on visual input, whereas the estimate used to compute the joint-based motor command relies more on proprioceptive signals. This suggests that when estimating the position of the arm, the brain selects different combinations of sensory input based on the computation in which the resulting estimate will be used.

Adult↗

PubMed2003

From computerized patient records to national resource.

To help curb constantly rising costs of medical services, healthcare providers in Israel have been busy incorporating computerized patient record systems (CPR) into their organizations since the early 1990s. Our CPR based integrated system solutions (named Clicks) now serve over 90% of primary and secondary medical care professionals throughout the country, covering over 90% of the population across medical fields with all healthcare providers. Online verification of member rights, embedded business rules and medical protocols as well as Preventive Medical Assistance (PMA) rules are incorporated into the system. These, coupled by bi-directional communication to facilitate implementation and enforcement at all points of service and to transmit administrative and focal medical information, have created a firm foundation for carrying out the organization's cost control and expense management strategies. The CPR systems based on these underlying concepts and on token driven data entry methodology have transformed traditional medical work areas into virtually paperless environments. The enterprise wide solutions use dedicated viewports to address the needs and requirements of any medical field, user population and a wide range of medical facilities. Extensive data collection and detailed documentation are maintained universally at all points of service, for the entire patient population. Current applications, based on a distributed approach and local databases with communication to central systems for bi-directional transfer of information, gradually give way to unified databases located on central systems. Two concepts are being implemented: (a) MDC (Medical Data Core), which contains patients' focal medical data as transmitted from the local database at the physician's workstation, and (b) a complete centrally located database, where continuous communication is required from the physician's workstation to the central system, through dumb terminals. This concept entails massive investment in communication capacity and hardware and requires high reliability of all communication transactions at all times. MDC information by contrast does not require open communication lines around the clock, is communicated bi-directionally at predefined points in time or in the workflow, alleviating load and congestion on communication lines. In addition, access, retrieval and display of MDC information is done using standard browsing techniques under known protocols and requires no extra investment for these capabilities.

Diffusion of Innovation↗

PubMed2004

[The nursing field in education].

"Campus Extens" is a new correspondence course/open university educational project which makes use of new technologies in communication such as the Internet or videoconferences for the diffusion of its course content. This program commenced in 1997 as a provisional experimental program at the University of the Balearic Islands; at present, after six years up and running, this program is an established program. Classes in nursing were introduced as part of this program, due to a request by the Nursing Department, in an experimental provisional format since the academic year 2001-02 hoping to integrate new educational technologies and bring these closer to students in the Balearic Isles who find it difficult to attend traditional classes which are taught on the Palma campus and at the same time to make future correspondence courses possible. Taking the pedagogical materials which correspond to the Nursing Fundamentals course as an example, the authors describe the characteristics of this system, the educational model implemented, the didactic strategies which are used in this virtual classroom environment, as well as the methodological arrangement and the didactic materials which have been developed for this program. Finally, the authors want to point out that the participation of Nursing in this program has enabled the Nursing Department to respond to the educational and professional demands of the University of the Balearic Islands, to reflect critically about teaching methodology, to bring the School of Nursing and Physiotherapy closer to our university community and to design new projects for future correspondence/open university courses.

Education, Distance↗

PubMed2004

Immersive Virtual Telepresence: virtual reality meets eHealth.

Immersive Virtual Telepresence (IVT) tools are virtual reality environments combined with wireless multimedia facilities--real-time video and audio--and advanced input devices--tracking sensors, biosensors, brain-computer interfaces. For its features IVT can be considered an innovative communication interface based on interactive 3D visualization, able to collect and integrate different inputs and data sets in a single real-like experience. In this paper we try to outline the current state of research and technology that is relevant to the development of IVT in medicine. Moreover, we discuss the clinical principles and possible advantages associated with the use of IVT in this field.

Biosensing Techniques↗

PubMed2004

The role of vection, eye movements and postural instability in the etiology of motion sickness.

Motion sickness is a term that is commonly used to describe the ill effects of many provocative motion (e.g. seagoing or air travel) and apparent motion (e.g. IMAX movies and virtual reality) environments on human well-being and performance. It can be extremely debilitating and yet we do not have a precise understanding of its cause. This study evaluates the importance of three factors that are purported to be involved in the etiology of motion sickness (MS). Most provocative motion environments cause three distinct, but possibly related, responses: reflexive eye movements (EM), sensory conflict (SC), and postural instability (PS). Three current theories, concerning the etiology of motion sickness, emphasize one of these responses, but deny the importance of the others. Such theoretical approaches preclude the possibility of a synergistic interaction of these factors. This experiment employed a three-factor experimental design wherein each factor was manipulated alone or in combination with the others. The independent variables involved two levels of: PS (induced by having the subject stand on a stationary platform or on a posturally challenging platform mounted atop a partially inflated rubber inner tube); SC (with or without illusory self movement elicited visually by whole field stimulation); and EM (unrestricted or controlled by a stable fixation point). Analysis of measures of PS, SC and EM confirmed the effectiveness of these manipulations. Analysis of MS measures (questionnaires, magnitude ratings, tolerance times) revealed a main effect of SC (p < 0.01), increased MS found with illusory self motion conditions. In addition, measures of MS symptomatology revealed a significant three-way interaction between SC, PS and EM (p < 0.05), greater amounts of MS found with conditions of illusory self motion, postural challenge, and unrestricted EM. This suggests support for a multi-factorial approach to the study of MS etiology. These findings suggest a major role of SC in the elicitation of MS, but also suggest important contributions from the EM and PS mechanisms.

Adolescent↗

PubMed2002

Heuristic haptic texture for surgical simulations.

Generation of credible force feedback renderings adds the sense of touch crucial for the development of a realistic virtual surgical environment. However, a number of difficulties must be overcome before this can be achieved. One of the problems is the paucity of data on the in-vivo tissue compliance properties needed to generate acceptable output forces. Without this "haptic texture," the sense of touch component remains relatively primitive and unrealistic. Current research in the quantitative analysis of biomechanics of living tissue, including collection of in-vivo tissue compliance data using specialized sensors, has made tremendous progress. However, integration of all facets of biomechanical data in order to transfer them into haptic texture remains a very difficult problem. For this reason, we are attempting to create a library of heuristic haptic textures of anatomical structures. The library of heuristic haptic textures will capture the expert's sense of feel for selected anatomical structures and will be used to convey the sense of touch for surgical training simulations. Once the techniques for converting biomechanical data into haptic texture become more robust, this library can be used as a benchmark to verify theoretical computational models used for generating output forces in haptic devices.

Biomechanical Phenomena↗

PubMed2004

Phantom-based interactive simulation system for dental treatment training.

In this paper, we propose a new interactive simulation system for dental treatment training. The system comprises a virtual reality environment and a force-torque measuring device to enhance the capabilities of a passive phantom of tooth anatomy in dental treatment training processes. The measuring device is connected to the phantom, and provides essential input data for generating the graphic animations of physical behaviors such as drilling and bleeding. The animation methods of those physical behaviors are also presented. This system is not only able to enhance interactivity and accessibility of the training system compared to conventional methods but it also provides possibilities of recording, evaluating, and verifying the training results.

Computer Simulation↗

PubMed2005

The virtual terrorism response academy: training for high-risk, low-frequency threats.

The Virtual Terrorism Response Academy is a reusable virtual learning environment to prepare emergency responders to deal with high-risk, low-frequency events in general, terrorist attacks in particular. The principal learning strategy is a traditional one: apprenticeship. Trainees enter the Academy and travel through its halls, selecting different learning experiences under the guidance of instructors who are simultaneously master practitioners and master trainers. The mentors are real individuals who have been videotaped according to courseware designs; they are subsequently available at any time or location via broadband Internet or CD-ROM. The Academy features a Simulation Area where trainees are briefed on a given scenario, select appropriate resources (e.g., protective equipment and hazmat instruments), then enter a 3-dimensional space where they must deal with various situations. Simulations are done under the guidance of a master trainer who functions as a coach, asking questions, pointing out things, explaining his reasoning at various points in the simulation. This is followed by a debriefing and discussion of lessons that could be learned from the simulation and the trainee's decisions.

Computer Simulation↗

PubMed2005

Real-time haptic interface for VR colonoscopy simulation.

Colonoscopy is an endoscopic medical procedure where the colon of the patient is examined. This minimally invasive technique is performed with a colonoscope, a long tube with an integrated imaging device at its tip. The doctors performing these procedures require high skills in multiple domains such as hand-eye coordination, visualization, safety and ease at guiding flexible endoscopes. The importance of training colonoscopy procedures rises with the growth of variety of colon diseases. In order to safely train surgeons to these procedures, a computer-assisted haptic simulator is proposed. This paper describes both the haptic hardware interface and virtual reality software that compose the training system. A high friction belt is used to render the required forces and to insure the absence of slippage. A differential drive actuated with two DC motors enables to set the system into translation and rotation. A virtual reality environment has been developed to provide real-time visualisation and force feedback.

Colonoscopy↗

PubMed2005

Simulation of color deficiency in virtual reality.

Color deficiency protanopia is simulated in a virtual home environment. A color database is created to set the corresponding relation between each color for normal vision and for protanopia. Based on this database, a second texture system is set up for the home model. The proper texture system is used according to the user's choice on the interactive menu.

Color Vision Defects↗

PubMed2005

Automated renderer for visible human and volumetric scan segmentations.

Creating a library of binary segmentation mask sequences for the abdominal anatomy hierarchy of SNOMED and developing a quick, flexible automatic method for generating iso-surface models from these named structure masks has been a primary goal in our research. This paper describes our development of a clear path for computing visualizations of arbitrary groups of organs from these masks (typically generated from Visible Human data). One use of these methods is teaching the anatomy of various organ systems in the human body using virtual reality environments.

Computer Simulation↗

PubMed2005

Grid requirements for the integration of biomedical information resources for health applications.

OBJECTIVES: The goal of this paper is to identify how Grid technology can be applied for the development and deployment of integration systems, bringing together distributed and heterogeneous biomedical information sources for medical applications. METHODS: The integration of new genetic and medical knowledge in clinical workflows requires the development of new paradigms for information management in which the ability to access and relate disparate data sources is essential. We adopt a requirements perspective based on the user needs we have identified in the development of the INFOGENMED system to assess current Grid technology against those requirements. RESULTS: The gap between Grid features and distributed biomedical information integration needs is characterized. Results from prospective studies are also reported. CONCLUSIONS: Grid infrastructures offer advanced features for the deployment of collaborative computational environments across virtual organizations. New Grid developments are in line with the problem of multiple site information integration. From the INFOGENMED point of view, Grid infrastructures need to evolve to implement structured data access services and semantic content description and discovery.

Computational Biology↗

PubMed2004

A grid computing infrastructure for MEG data analysis.

Magnetoencephalography (MEG) is widely used for studying brain functions, but clinical applications of MEG have been less prevalent. One reason is that only clinicians who have highly specialized knowledge can use MEG diagnostically, and such clinicians are found at only a few major hospitals. Another reason is that MEG data analysis is getting more and more complicated, and deals with a large amount of data, and thus requires high-performance computing. These problems can be solved by the collaboration of human and computing resources distributed in multiple facilities. A new computing infrastructure for brain scientists and clinicians in distant locations was therefore developed by the Grid technology, which provides virtual computing environments composed of geographically distributed computers and experimental devices. A prototype system connecting an MEG system at the AIST in Japan, a Grid environment composed of PC clusters at Osaka University in Japan and Nanyang Technological University in Singapore, and user terminals in Baltimore was developed. MEG data measured at the AIST were transferred in real-time through a 1-GB/s network to the PC clusters for processing by a wavelet cross-correlation method, and then monitored in Baltimore. The current system is the basic model for remote-access to MEG equipment and high-speed processing of MEG data.

Computing Methodologies↗

PubMed2005

Neuroendoscopic management of haematocephalus.

The purpose of the paper was to publish the results of endoscopic treatment of primary and secondary haematocephalus in the group of 23 patients, treated by means of Wolf endoscopic system combined with frame based navigation with the aid of virtual reality environment. The procedure is aimed to remove blood clots from the cerebral ventricles and to reduce the volume of parenchymal haematoma in secondary haematocephalus during single surgical session. In the majority of the treated patients septostomy was added to make revision of both lateral ventricles possible from a single approach, and the operation was completed with endoscopic third ventriculostomy to reduce the amount of blood in the basal cisterns and to reestablish the patency of cerebrospinal fluid pathways, so that lumbar puncture can be safely done to facilitate the process of cleaning blood away from the cerebrospinal fluid. The surgery always facilitates the resorption of residual blood as well as blood degradation products, therefore late complications, such as posthaemorrhagic hydrocephalus, membranes and stenosis formation was prevented. Improvement of the clinical condition was obtained without the need for permanent drainage systems insertion. Lethal outcome in one patient and unfavourable clinical result in another three patients were unrelated to the endoscopic treatment. (Tab. 1, Fig. 2, Ref: 10.)

Adult↗