An innovative virtual reality training tool for orthognathic surgery

Virtual reality (VR) surgery using Oculus Rift and Leap Motion devices is a multi-sensory, holistic surgical training experience. A multimedia combination including 360° videos, three-dimensional interaction, and stereoscopic videos in VR has been developed to enable trainees to experience a realistic surgery environment. The innovation allows trainees to interact with the individual components of the maxillofacial anatomy and apply surgical instruments while watching close-up stereoscopic three-dimensional videos of the surgery. In this study, a novel training tool for Le Fort I osteotomy based on immersive virtual reality (iVR) was developed and validated. Seven consultant oral and maxillofacial surgeons evaluated the application for face and content validity. Using a structured assessment process, the surgeons commented on the content of the developed training tool, its realism and usability, and the applicability of VR surgery for orthognathic surgical training. The results confirmed the clinical applicability of VR for delivering training in orthognathic surgery. Modifications were suggested to improve the user experience and interactions with the surgical instruments. This training tool is ready for testing with surgical trainees

Effectiveness of immersive virtual reality in surgical training—A randomized control trial

Purpose: Surgical training methods are evolving with the technological advancements, including the application of virtual reality (VR) and augmented reality. However, 28 to 40% of novice residents are not confident in performing a major surgical procedure. VR surgery, an immersive VR (iVR) experience, was developed using Oculus Rift and Leap Motion devices (Leap Motion, Inc, San Francisco, CA) to address this challenge. Our iVR is a multisensory, holistic surgical training application that demonstrates a maxillofacial surgical technique, the Le Fort I osteotomy. The main objective of the present study was to evaluate the effect of using VR surgery on the self-confidence and knowledge of surgical residents. Materials and Methods: A multisite, single-blind, parallel, randomized controlled trial (RCT) was performed. The participants were novice surgical residents with limited experience in performing the Le Fort I osteotomy. The primary outcome measures were the self-assessment scores of trainee confidence using a Likert scale and an objective assessment of the cognitive skills. Ninety-five residents from 7 dental schools were included in the RCT. The participants were randomly divided into a study group of 51 residents and a control group of 44. Participants in the study group used the VR surgery application on an Oculus Rift with Leap Motion device. The control group participants used similar content in a standard PowerPoint presentation on a laptop. Repeated measures multivariate analysis of variance was applied to the data to assess the overall effect of the intervention on the confidence of the residents. Results: The study group participants showed significantly greater perceived self-confidence levels compared with those in the control group (P = .034; α = 0.05). Novices in the first year of their training showed the greatest improvement in their confidence compared with those in their second and third year. Conclusions: iVR experiences improve the knowledge and self-confidence of the surgical residents

An innovative virtual reality training tool for orthognathic surgery

Virtual reality (VR) surgery using Oculus Rift and Leap Motion devices is a multi-sensory, holistic surgical training experience. A multimedia combination including 360° videos, three-dimensional interaction, and stereoscopic videos in VR has been developed to enable trainees to experience a realistic surgery environment. The innovation allows trainees to interact with the individual components of the maxillofacial anatomy and apply surgical instruments while watching close-up stereoscopic three-dimensional videos of the surgery. In this study, a novel training tool for Le Fort I osteotomy based on immersive virtual reality (iVR) was developed and validated. Seven consultant oral and maxillofacial surgeons evaluated the application for face and content validity. Using a structured assessment process, the surgeons commented on the content of the developed training tool, its realism and usability, and the applicability of VR surgery for orthognathic surgical training. The results confirmed the clinical applicability of VR for delivering training in orthognathic surgery. Modifications were suggested to improve the user experience and interactions with the surgical instruments. This training tool is ready for testing with surgical trainees

Family violence, war, and natural disasters: A study of the effect of extreme stress on children's mental health in Sri Lanka

Catani C, Jacob N, Schauer E, Kohila M, Neuner F. Family violence, war, and natural disasters: a study of the effect of extreme stress on children's mental health in Sri Lanka. BMC Psychiatry. 2008;8(1): 33.BACKGROUND: The consequences of war violence and natural disasters on the mental health of children as well as on family dynamics remain poorly understood. Aim of the present investigation was to establish the prevalence and predictors of traumatic stress related to war, family violence and the recent Tsunami experience in children living in a region affected by a long-lasting violent conflict. In addition, the study looked at whether higher levels of war violence would be related to higher levels of violence within the family and whether this would result in higher rates of psychological problems in the affected children. METHODS: 296 Tamil school children in Sri Lanka's North-Eastern provinces were randomly selected for the survey. Diagnostic interviews were carried out by extensively trained local Master level counselors. PTSD symptoms were established by means of a validated Tamil version of the UCLA PTSD Index. Additionally, participants completed a detailed checklist of event types related to organized and family violence. RESULTS: 82.4% of the children had experienced at least one war-related event. 95.6% reported at least one aversive experience out of the family violence spectrum. The consequences are reflected in a 30.4% PTSD and a 19.6% Major Depression prevalence. Linear regression analyses showed that fathers' alcohol intake and previous exposure to war were significantly linked to the amount of maltreatment reported by the child. A clear dose-effect relationship between exposure to various stressful experiences and PTSD was found in the examined children. CONCLUSION: Data argue for a relationship between war violence and violent behavior inflicted on children in their families. Both of these factors, together with the experience of the recent Tsunami, resulted as significant predictors of PTSD in children, thus highlighting the detrimental effect that the experience of cumulative stress can have on children's mental health

Mental Health and School Functioning for Girls in the Child Welfare System : the Mediating Role of Future Orientation and School Engagement

This study investigated the association between mental health problems and academic and behavioral school functioning for adolescent girls in the child welfare system and determined whether school engagement and future orientation meditated the relationship. Participants were 231 girls aged between 12 and 19 who had been involved with the child welfare system. Results indicated that 39% of girls reported depressive symptoms in the clinical range and 54% reported posttraumatic symptoms in the clinical range. The most common school functioning problems reported were failing a class (41%) and physical fights with other students (35%). Participants reported a mean number of 1.7 school functioning problems. Higher levels of depression and PTSD were significantly associated with more school functioning problems. School engagement fully mediated the relationship between depression and school functioning and between PTSD and school functioning, both models controlling for age, race, and placement stability. Future orientation was not significantly associated with school functioning problems at the bivariate level. Findings suggest that school engagement is a potentially modifiable target for interventions aiming to ameliorate the negative influence of mental health problems on school functioning for adolescent girls with histories of abuse or neglect

The incremental Fourier classifier: Leveraging the discrete Fourier transform for classifying high speed data streams

Two major performance bottlenecks with decision tree based classifiers in a data stream environment are the depth of the tree and the update overhead of maintaining leaf node statistics on an instance-wise basis to ensure that classification is consistent with the current state of the data stream. Previous research has shown that classifiers based on Fourier spectra derived from decision trees produce compact array structures that can be searched and maintained much more efficiently than deep tree based structures. However, the key issue of incrementally adapting the spectrum to changes has not been addressed. In this research we present a strategy for incremental maintenance of the Fourier spectrum to changes in concept that take place in data stream environments. Along with the incremental approach we also propose schemes for feature selection and synopsis generation that enable the coefficient array to be refreshed efficiently on a periodic basis. Our empirical evaluation on a number of widely used stream classifiers reveals that the Fourier classifier outperforms them, both in terms of classification accuracy as well as speed of classification

Mobile robot tracking of pre-planned paths

A method of mobile robot steering control around pre-planned paths is presented. The system can maneuver accurately at low speeds by deriving control parameters as functions of vehicle velocity. The peak demand on the steering controller is reduced, by distributing steering curvature changes evenly over the extent of a maneuver