Outcomes of a virtual-reality simulator-training programme on basic surgical skills in robot-assisted laparoscopic surgery

Background The utility of the virtual-reality robotic simulator in training programmes has not been clearly evaluated. Our aim was to evaluate the impact of a virtual-reality robotic simulator-training programme on basic surgical skills. Methods A simulator-training programme in robotic surgery, using the da Vinci Skills Simulator, was evaluated in a population including junior and seasoned surgeons, and non-physicians. Their performances on robotic dots and suturing-skin pod platforms before and after virtual-simulation training were rated anonymously by surgeons experienced in robotics. Results 39 participants were enrolled: 14 medical students and residents in surgery, 14 seasoned surgeons, 11 non-physicians. Junior and seasoned surgeons’ performances on platforms were not significantly improved after virtual-reality robotic simulation in any of the skill domains, in contrast to non-physicians. Conclusions The benefits of virtual-reality simulator training on several tasks to basic skills in robotic surgery were not obvious among surgeons in our initial and early experience with the simulator

Virtual Legendrian Isotopy

An elementary stabilization of a Legendrian link $L$ in the spherical cotangent bundle $ST^*M$ of a surface $M$ is a surgery that results in attaching a handle to $M$ along two discs away from the image in $M$ of the projection of the link $L$. A virtual Legendrian isotopy is a composition of stabilizations, destabilizations and Legendrian isotopies. In contrast to Legendrian knots, virtual Legendrian knots enjoy the property that there is a bijective correspondence between the virtual Legendrian knots and the equivalence classes of Gauss diagrams. We study virtual Legendrian isotopy classes of Legendrian links and show that every such class contains a unique irreducible representative. In particular we get a solution to the following conjecture of Cahn, Levi and the first author: two Legendrian knots in $ST^*S^2$ that are isotopic as virtual Legendrian knots must be Legendrian isotopic in $ST^*S^2.$Comment: 10 pages, 4 figur

A Surgical Virtual Learning Environment

A computer based Virtual Learning Environment is proposed for training and evaluating novice surgeons. Although this Virtual Learning Environments is thought to be useful in other learning situations as well, especially where knowledge of different complex procedures and the ability to correctly assess a complex situation is critical, in this project we specifically focus on vascular surgery. This environment will be developed as part of the DIME project (Distributed Interactive Medical Exploratory). We are building this Virtual Learning Environment using a new navigational metaphor, which affords modeling the learning process, rather than focusing solely on modeling the operating room. This 'navigational metaphor' can be thought of as an semi-threedimensional interface to a database containing multimedia fragments and expert annotations of the knowledge domain under study

NOViSE: a virtual natural orifice transluminal endoscopic surgery simulator

Purpose: Natural Orifice Transluminal Endoscopic Surgery (NOTES) is a novel technique in minimally invasive surgery whereby a flexible endoscope is inserted via a natural orifice to gain access to the abdominal cavity, leaving no external scars. This innovative use of flexible endoscopy creates many new challenges and is associated with a steep learning curve for clinicians. Methods: We developed NOViSE - the first force-feedback enabled virtual reality simulator for NOTES training supporting a flexible endoscope. The haptic device is custom built and the behaviour of the virtual flexible endoscope is based on an established theoretical framework – the Cosserat Theory of Elastic Rods. Results: We present the application of NOViSE to the simulation of a hybrid trans-gastric cholecystectomy procedure. Preliminary results of face, content and construct validation have previously shown that NOViSE delivers the required level of realism for training of endoscopic manipulation skills specific to NOTES Conclusions: VR simulation of NOTES procedures can contribute to surgical training and improve the educational experience without putting patients at risk, raising ethical issues or requiring expensive animal or cadaver facilities. In the context of an experimental technique, NOViSE could potentially facilitate NOTES development and contribute to its wider use by keeping practitioners up to date with this novel surgical technique. NOViSE is a first prototype and the initial results indicate that it provides promising foundations for further development

The virtual Haken conjecture: Experiments and examples

A 3-manifold is Haken if it contains a topologically essential surface. The Virtual Haken Conjecture says that every irreducible 3-manifold with infinite fundamental group has a finite cover which is Haken. Here, we discuss two interrelated topics concerning this conjecture. First, we describe computer experiments which give strong evidence that the Virtual Haken Conjecture is true for hyperbolic 3-manifolds. We took the complete Hodgson-Weeks census of 10,986 small-volume closed hyperbolic 3-manifolds, and for each of them found finite covers which are Haken. There are interesting and unexplained patterns in the data which may lead to a better understanding of this problem. Second, we discuss a method for transferring the virtual Haken property under Dehn filling. In particular, we show that if a 3-manifold with torus boundary has a Seifert fibered Dehn filling with hyperbolic base orbifold, then most of the Dehn filled manifolds are virtually Haken. We use this to show that every non-trivial Dehn surgery on the figure-8 knot is virtually Haken.Comment: Published by Geometry and Topology at http://www.maths.warwick.ac.uk/gt/GTVol7/paper12.abs.htm

Virtual reality training and assessment in laparoscopic rectum surgery

Background: Virtual-reality (VR) based simulation techniques offer an efficient and low cost alternative to conventional surgery training. This article describes a VR training and assessment system in laparoscopic rectum surgery. Methods: To give a realistic visual performance of interaction between membrane tissue and surgery tools, a generalized cylinder based collision detection and a multi-layer mass-spring model are presented. A dynamic assessment model is also designed for hierarchy training evaluation. Results: With this simulator, trainees can operate on the virtual rectum with both visual and haptic sensation feedback simultaneously. The system also offers surgeons instructions in real time when improper manipulation happens. The simulator has been tested and evaluated by ten subjects. Conclusions: This prototype system has been verified by colorectal surgeons through a pilot study. They believe the visual performance and the tactile feedback are realistic. It exhibits the potential to effectively improve the surgical skills of trainee surgeons and significantly shorten their learning curve. © 2014 John Wiley & Sons, Ltd

New technologies in rhinoplasty : a comprehensive workflow for computer-assisted planning and execution

Rhinoplasty in facial cleft patients is among the most challenging types of reconstructive facial surgery due to its variability Advances in 3-dimensional imaging enable improved preoperative assessment in rhinoplasty. In complex cases with bony support irregularities and asymmetry, it is rational to initiate planning with reconstruction of the aberrant substructure (ie, "bottom-up" planning) rather than starting the surgical design with soft-tissue morphing. We present a new comprehensive workflow in which novel advanced technologies are implemented to perform "bottom-up" computer-assisted planning and execution in complex rhinoplasty cases. This workflow enables meticulous planning, use of grafting templates, and 3-dimensional-guided osteotomies with integration of piezotome and intraoperative navigation. Previous reports separately discuss some of these innovations. However, greater benefit lies in the combination of these techniques, with emphasis on preoperative computer analysis, virtual planning, and transfer to the operation theater. Surgeons are seeking new ways to enhance minimally invasive approaches and to obtain predictable and favorable clinical results. The presently introduced workflow allows clinicians to plan complex cases in a simple, effective, and safe manner, with the combination of different techniques to produce consistent results