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At least 685 records · Page 38Linked to original sources
PubMed2001

A virtual classroom for undergraduate periodontology: a pilot study.

The Integrated Distributed Learning Environments or virtual classrooms constitute a new promising structure in education of health care personnel. A virtual classroom was developed aiming to teach periodontology to an international group of 28 dental students using a problem-based learning (PBL) approach. The course was web-based and included synchronous and asynchronous communication, on-line libraries and multimedia material. Students were organised in 4 independent groups and each group was appointed a tutor. The results of the study indicate that one of the most positive effects students experienced was competence in using the computer. They also rated highly the use of multimedia for learning of clinical procedures. It was found that web boards and email were too slow to allow group work in the virtual classroom. Real time communication programs were found to be superior for problem discussion and hypothesis formulation. However, email and the web board played a significant role during certain steps of the PBL method. The students expressed a positive attitude for the combined use of network-based learning and problem-based education. Our present experience suggests that distance learning should be organised with a mixture of different media, allowing communication of knowledge and skills between the resources and the students, as well as cooperation between the students. Computer literacy among teachers and students is limited and should be enhanced. Finally, personal contact between the resource persons and the students before the distant learning course commences helps the learning process.

Attitude↗
PubMed2006

Flatland sound services design supports virtual medical training simulations.

This paper describes the evolution of the design of Flatland Sound Service (FSS), a sound system for virtual reality required to support Project TOUCH (Telehealth Outreach for Unified Community Health), a multi-year collaboration between the Schools of Medicine at the state Universities of Hawaii and of New Mexico. Two virtual sonic environments specific case scenarios, a neurological trauma (Toma) and a virtual kidney nephron (Nephron), were developed using integrated services provided by FSS. Flatland is an open source visualization and virtual reality application development tool created at the University of New Mexico.

Computer Simulation↗
PubMedDate not supplied

The virtual nose: a 3-dimensional virtual reality model of the human nose.

BACKGROUND: The 3-dimensionally complex interplay of soft tissue, cartilaginous, and bony elements makes the mastery of nasal anatomy difficult. Conventional methods of learning nasal anatomy exist, but they often involve a steep learning curve. Computerized models and virtual reality applications have been used to facilitate teaching in a number of other complex anatomical regions, such as the human temporal bone and pelvic floor. We present a 3-dimensional (3-D) virtual reality model of the human nose. METHODS: Human cadaveric axial cross-sectional (0.33-mm cuts) photographic data of the head and neck were used. With 460 digitized images, individual structures were traced and programmed to create a computerized polygonal model of the nose. Further refinements to this model were made using a number of specialized computer programs. This 3-D computer model of the nose was then programmed to operate as a virtual reality model. RESULTS: Anatomically correct 3-D model of the nose was produced. High-resolution images of the "virtual nose" demonstrate the nasal septum, lower lateral cartilages, middle vault, bony dorsum, and other structural details of the nose. Also, the model can be combined with a separate virtual reality model of the face and its skin cover as well as the skull. The user can manipulate the model in space, examine 3-D anatomical relationships, and fade superficial structures to reveal deeper ones. CONCLUSIONS: The virtual nose is a 3-D virtual reality model of the nose that is accurate and easy to use. It can be run on a personal computer or in a specialized virtual reality environment. It can serve as an effective teaching tool. As the first virtual reality model of the nose, it establishes a virtual reality platform from which future applications can be launched.

Humans↗
PubMed2001

Does training in a virtual reality simulator improve surgical performance?

BACKGROUND: The development of computerized surgical simulators in a virtual reality environment demands models for proper validation. Recent investigations have shown that a virtual reality simulator (MIST-VR) is a reliable tool for the assessment of laparoscopic psychomotor skills and that it improves the automation of the so-called fulcrum effect. Therefore, we set out to determine whether training with the MIST-VR would improve the surgical performance of surgically inexperienced medical students and to see if results obtained in the simulator would correlate with surgical performance. METHODS: A total of 29 medical students were randomized into two groups. One group received preoperative MIST-VR training. Both groups then performed a simulated laparoscopic appendectomy in a pig. The operations were videotaped and examined by three independent observers. RESULTS: There was no significant difference in performance between the two groups. The performance with the MIST-VR correlated with the results in surgery. CONCLUSION: A method that can measure surgical skill, based on the scoring of independent observers who view videotaped performances, seems to be reliable. MIST-VR did not improve the surgical skills of the subjects, but the results with MIST-VR did predict surgical outcome.

Clinical Competence↗
PubMed2003

Virtual reality therapy in aid of senior citizens' psychological disorders.

The treatment for senior citizens suffering from psychological disorders seems to be different from therapeutic procedures used for other populations. This pilot study is the first known in-depth case study of the effectiveness of virtual reality therapy (VRT) as a treatment for senior citizens. The fear of flying treatment was chosen for this study. The subject of the study was a 62-year-old married female, whose anxiety and avoidance behavior was interfering with her normal activities. For treatment, she was placed in the cabin of a virtual commercial aircraft environment accompanied by a virtual therapist. After a few sessions in which she spent time in a virtual airport scene, she spent four sessions in which she was flown over a simulated city. While under the virtual reality treatment, the subject experienced a number of physical and emotional anxiety-related symptoms. These symptoms included sweaty palms, loss of balance, weakness in the knees, etc. In this study, the virtual reality treatment caused a significant reduction in the anxiety symptoms in the subject and enhanced her ability to face phobic situations in the real world. Since termination of the treatment, she has taken several flights to professional conferences and reported feeling more comfortable and has fewer symptoms than those experienced prior to the VRT treatment.

Aviation↗
PubMed2004

Reaching in reality and virtual reality: a comparison of movement kinematics in healthy subjects and in adults with hemiparesis.

BACKGROUND: Virtual reality (VR) is an innovative tool for sensorimotor rehabilitation increasingly being employed in clinical and community settings. Despite the growing interest in VR, few studies have determined the validity of movements made in VR environments with respect to real physical environments. The goal of this study was to compare movements done in physical and virtual environments in adults with motor deficits to those in healthy individuals. METHODS: The participants were 8 healthy adults and 7 adults with mild left hemiparesis due to stroke. Kinematics of functional arm movements involving reaching, grasping and releasing made in physical and virtual environments were analyzed in two phases: 1) reaching and grasping the ball and 2) ball transport and release. The virtual environment included interaction with an object on a 2D computer screen and haptic force feedback from a virtual ball. Temporal and spatial parameters of reaching and grasping were determined for each phase. RESULTS: Individuals in both groups were able to reach, grasp, transport, place and release the virtual and real ball using similar movement strategies. In healthy subjects, reaching and grasping movements in both environments were similar but these subjects used less wrist extension and more elbow extension to place the ball on the virtual vertical surface. Participants with hemiparesis made slower movements in both environments compared to healthy subjects and during transport and placing of the ball, trajectories were more curved and interjoint coordination was altered. Despite these differences, patients with hemiparesis also tended to use less wrist extension during the whole movement and more elbow extension at the end of the placing phase. CONCLUSION: Differences in movements made by healthy subjects in the two environments may be explained by the use of a 2D instead of a 3D virtual environment and the absence of haptic feedback from the VR target. Despite these differences, our findings suggest that both healthy subjects and individuals with motor deficits used similar movement strategies when grasping and placing a ball in the two reality conditions. This suggests that training of arm movements in VR environments may be a valid approach to the rehabilitation of patients with motor disorders.

Journal Article↗
PubMedDate not supplied

[Distance education: use of the WebCT as a support tool for teaching intravenous therapy in nursing undergraduate programs].

This investigation focused on a learning environment via internet, through which Intravenous Therapy (IVT) was taught. Due to its complexity, Intravenous Therapy was chosen against numerous subjects to be taught through an e-learning environment, by comprising both technical procedures and conceptual aspects that can be discussed through a virtual learning environment. The objectives of this study were to develop educational material about Intravenous Therapy to guide students through the learning related to intravenous therapy, to have the related educational material evaluated by experts, and to evaluate the students' use of this material, considering difficulties and/or advantages, participation/interaction in this environment, and usability of its tools. The interface used for the internet-based training program was WebCT.

Brazil↗
PubMed2005

Virtually driving: are the driving environments "real enough" for exposure therapy with accident victims? An explorative study.

There is a small but growing body of research supporting the effectiveness of computer-generated environments in exposure therapy for driving phobia. However, research also suggests that difficulties can readily arise whereby patients do not immerse in simulated driving scenes. The simulated driving environments are not "real enough" to undertake exposure therapy. This sets a limitation to the use of virtual reality (VR) exposure therapy as a treatment modality for driving phobia. The aim of this study was to investigate if a clinically acceptable immersion/presence rate of >80% could be achieved for driving phobia subjects in computer generated environments by modifying external factors in the driving environment. Eleven patients referred from the Accident and Emergency Department of a general hospital or from their General Practitioner following a motor vehicle accident, who met DSM-IV criteria for Specific Phobia-driving were exposed to a computer-generated driving environment using computer driving games (London Racer/Midtown Madness). In an attempt to make the driving environments "real enough," external factors were modified by (a) projection of images onto a large screen, (b) viewing the scene through a windscreen, (c) using car seats for both driver and passenger, and (d) increasing vibration sense through use of more powerful subwoofers. Patients undertook a trial session involving driving through computer environments with graded risk of an accident. "Immersion/presence" was operationally defined as a subjective rating by the subject that the environment "feels real," together with an increase in subjective units of distress (SUD) ratings of >3 and/or an increase of heart rate of >15 beats per minute (BPM). Ten of 11 (91%) of the driving phobic subjects met the criteria for immersion/presence in the driving environment enabling progression to VR exposure therapy. These provisional findings suggest that the paradigm adopted in this study might be an effective and relatively inexpensive means of developing driving environments "real enough," to make VR exposure therapy a viable treatment modality for driving phobia following a motor vehicle accident (MVA).

Accidents, Traffic↗
PubMed2000

Augmented reality simulator for training in two-dimensional echocardiography.

In two-dimensional echocardiography the sonographer must synthesize multiple tomographic slices into a mental three-dimensional (3D) model of the heart. Computer graphics and virtual reality environments are ideal to visualize complex 3D spatial relationships. In augmented reality (AR) applications, real and virtual image data are linked, to increase the information content. In the presented AR simulator a 3D surface model of the human heart is linked with echocardiographic volume data sets. The 3D echocardiographic data sets are registered with the heart model to establish spatial and temporal congruence. The heart model, together with an animated ultrasound sector represents a reference scenario, which displays the currently selected two-dimensional echocardiographic cutting plane calculated from the volume data set. Modifications of the cutting plane within the echocardiographic data are transferred and visualized simultaneously and in real time within the reference scenario. The trainee can interactively explore the 3D heart model and the registered 3D echocardiographic data sets by an animated ultrasound probe, whose position is controlled by an electromagnetic tracking system. The tracking system is attached to a dummy transducer and placed on a plastic puppet to give a realistic impression of a two-dimensional echocardiographic examination.

Computer Graphics↗
PubMed2004

A problem-based e-Learning prototype system for clinical medical education.

The purpose of this system is to establish virtual medical school (VMS) as the platform of e-learning center, which integrates collaborative and self-directed learning environment by virtual group, classroom and library, and automatically converts valuable clinical case from Hospital Information System (HIS) database into virtual patient by online authoring tools for problem-based e-learning. In this system, the VMS provides a problem-based e-learning environment, and utilizes HIS to capture and store valuable clinical cases. All medical students and residents now have the opportunity to learn from these typical cases online. The VMS at National Taiwan University has the potential to develop into a national medical education network for the meditation and provision of comprehensive medical resources. The system will use the international standard SCORM 1.2 to develop teaching material and assist with the HL7 v2.4, CDA v1.0 standards to connect Electronic Medical Record (EMR) systems in the hospital. It can provide resources sharing among medical centers by using high transportation ability of Grid Computing integrated with the broadband video platform, Access Grid, and personal multiple point videoconference platform, Multi-video, to popularize the application of e-learning in clinical medical education.

Clinical Medicine↗
PubMed2003

Three-dimensional surgical planning for maxillary and midface distraction osteogenesis.

Computerized surgical planning protocols for distraction osteogenesis are still in their rudimentary phase. The authors have developed a system to plan distraction osteogenesis in craniofacial and maxillofacial surgery that uses three-dimensional computed tomography scans and computer simulation in a virtual reality environment. This involves the creation of a three-dimensional bone model of the craniofacial skeleton, which incorporates virtual globes. Virtual osteotomies are performed on the bone model and the movements of the bone segments are simulated. The program generates a recipe for the linear and the angular changes necessary to achieve the desired outcome. The purpose of this article is to present this surgical planning process and discuss its use in maxillary and midface distraction.

Child↗
PubMed2006

Virtual reality applications to agoraphobia: a protocol.

Recently, educators and instructional designers have focused on the development and implementation of virtual learning environments that effectively combine theoretical and applied knowledge to teach university students. One of the trusts of the Psychology Virtual Teaching Laboratory in collaboration with the IXTLI observatory is to develop dissemination programs to promote the insertion of virtual reality (VR) technologies applied to rehabilitation in their clinical practice. This paper describes the development of (1) agoraphobia VR learning objects to be use as a teaching support tools in class and (2) a multimedia teaching program that incorporate digital video and VR scenarios address to students in the field of mental health. Promotion among professors and students about the use of this technology will allow us to initiate research in our country as well as to validate contextualized applications for our culture, therefore contributing with new advances in this field.

Agoraphobia↗
PubMed2005

Regional brain activation evoked when approaching a virtual human on a virtual walk.

We investigated the necessity of biological motion for activation of the posterior superior temporal sulcus (pSTS) in circumstances in which the rapid approach of the observer to a virtual human induced the observer to make inferences about the characters intentions. Using a virtual reality environment, subjects experienced themselves walking towards a complex scene composed of animate and/or inanimate objects. During "person" trials, the scene contained a virtual human either making a simple gesture such as scratching his face (Study 1) or standing completely still (Study 2). During "object" trials, the scenes contained items such as furniture, a face portrait, and a clock, but not the virtual human. Using functional MRI to measure brain activity, we demonstrated strong activity in the pSTS while the observer approached the social scene, but only when the virtual human was making gestures. This result emphasizes the importance of biological motion in inferring the intentions of others.

Adolescent↗
PubMedDate not supplied

The effect of the configuration and the interior design of a virtual weightless space station on human spatial orientation.

In a virtual weightless environment, subjects' orientation skills were studied to examine what kind of cognitive errors people make when they moved through the interior space of virtual space stations and what kind of visual information effectively decreases those errors. Subjects wearing a head-mounted display moved from one end to the other end in space station-like routes constructed of rectangular and cubical modules, and did Pointing and Modeling tasks. In Experiment 1, configurations of the routes were changed with such variables as the number of bends, the number of embedding planes, and the number of planes with respect to the body posture. The results indicated that spatial orientation ability was relevant to the variables and that orientational errors were explained by two causes. One of these was that the place, the direction, and the sequence of turns were incorrect. The other was that subjects did not recognize the rotation of the frame of reference, especially when they turned in pitch direction rather than in yaw. In Experiment 2, the effect of the interior design was examined by testing three design settings. Wall colors that showed the allocentric frame of reference and the different interior design of vertical and horizontal modules were effective; however, there was a limit to the effectiveness in complicated configurations.

Adult↗
PubMed2000

Path integration while ignoring irrelevant movement.

Participants attempted to return to the origin of travel after following an outbound path by locomotion on foot (Experiments 1-3) or in a virtual visual environment (Experiment 4). Critical conditions interrupted the outbound path with verbal distraction or irrelevant, to-be-ignored movements. Irrelevant movement, real or virtual, had greater effects than verbal or cognitive distraction, indicating inability to ignore displacement during path integration. Effects of the irrelevant movement's direction (backward vs. rightward) and location (1st vs. 2nd leg of path) indicated that participants encoded a configural representation of the pathway and then cognitively compensated for the movement, producing errors directly related to the demands of compensation. An encoding-error model fit to the data indicated that backward movement produced downward rescaling, whereas movement that led to implied rotation (rightward on 2nd leg) produced distortions of shape and scale.

Adult↗
PubMed1998

Modifications of body-image induced by virtual reality.

In contrast to the great number of publications on body image, only a few papers have focused on the treatment of a disturbed body image. In general, two direct and specific approaches are usually used, a cognitive/behavioural therapy to influence patient's feelings of dissatisfaction and a visuomotor therapy with the aim of influencing bodily awareness. The aim of this study was both to develop a virtual reality environment integrating the two approaches and to test its efficacy on a nonclinical sample of 24 women. Before and after a 10-min. virtual experience all the subjects made ratings on the Figure Rating Scale and the Contour Drawing Rating Scale. Analysis showed a significant reduction in body dissatisfaction without any major side effect.

Adult↗
PubMed2002

Virtual reality: immersive hepatic surgery educational environment.

BACKGROUND: Understanding the spatial relationships among the liver segments, and intrahepatic portal and hepatic veins is essential for surgical treatment of liver diseases. Teleimmersive virtual reality enables improved visualization over conventional media because it supports stereo vision, viewer-centered perspective, large angles of view, and interactivity with remote locations. We report a successful pilot study teaching hepatic surgical principles using teleimmersion. METHODS: We developed a teleimmersive environment for teaching with biomedical models including virtual models of the liver segments and portal and hepatic veins. Using the environment, 1 instructor gave a workshop to 6 senior general surgery residents at 2 physical locations. A 24-question (36-point) examination was administered before and after the workshop. RESULTS: The workshop produced significant improvements in the mean test scores between the pretests and posttests (17.67 to 23.67, P <.02). We found no differences between residents who were with the instructor and those at the remote location. Six-month delayed testing demonstrated complete retention of new knowledge. CONCLUSIONS: The teleimmersive environment enabled surgeons to overcome some of the barriers to teaching complex surgical anatomic principles. Using teleimmersive environments, surgical educators and trainees can interact from locations worldwide using virtual anatomic information to achieve their educational goals.

Biliary Tract↗