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A atividade garimpeira e tradicional na regiao centro-sul do estado do Mato Grosso desde o seculo XVIII, onde inicialmente as lavras de ouro se davam nos aluvioes e atualmente se concentram em filoes com ouro livre. Entretanto, recentes verificacoes mostraram a presenca de mineralizacoes disseminadas, uma forma incomum de ocorrencia na regiao, em dois depositos – Adao Rodui e Jonas Gimenez – localizados no municipio de Pocone e no distrito de Cangas, respectivamente. O minerio principal e constituido por ouro, em teores significativos, associado a pirita e magnetita subordinadamente. O presente trabalho apresenta a caracterizacao do minerio aurifero contido nestes depositos, em concentracoes que chegam a ate 25,15 ppm em rocha total e a 560,25 ppm em concentrados de sulfetos. O minerio e hospedado em rochas do Grupo Cuiaba (Faixa Paraguai), de idade neoproterozoica, relacionadas a Orogenia Brasiliana-Pan Africana. As rochas foram metamorfizadas em facies xisto verde, com evidencias de intensa alteracao hidrotermal do tipo disseminada, em veio e stockwork, formadores de quartzo, magnetita, pirita e ouro. As rochas hospedeiras sao descritas como pacotes espessos de filito e metarritmito, cujo acamamento sedimentar (S0) e sobreposto por tres fases deformacionais progressivas (D1, D2 e D3), que aparentemente controlaram a entrada dos fluidos hidrotermais mineralizantes. A fase D1 e geradora de foliacao S1 paralela ao acamamento sedimentar, dobras F1 recumbentes e uma familia de veios de quartzo V1 de direcao NE. A segunda fase deformacional D2 esta relacionada a uma foliacao penetrativa de alto ângulo S2, plano axial as dobras abertas a suaves, assimetricas e reclinadas F2 e uma familia de veios de quartzo V2 foliados e de direcao NE. A fase D3 tem caracteristicas predominantemente rupteis e e representada por familias de foliacoes de direcao NW S3, por vezes preenchidas por quartzo formando os veios V3, nao foliados. A ocorrencia de ouro associado a assembleias hidrotermais disseminadas ou em veios, com forte controle estrutural e litologico, relacionadas a estruturas deformacionais ducteis-rupteis em rochas metamorficas de baixo grau sugerem que as mineralizacoes estudadas sao do tipo ouro orogenico, apresentando similaridades com o deposito de Paracatu, em Minas Gerais, incluindo rochas hospedeiras, alteracao hidrotermal, minerais de minerio, ambiente tectonico e idade.

Diseases of the posterior segment of the eye are common causes of blindness and can be difficult to treat due to their location. Recently, there has been increased interest in the use of the suprachoroidal space to deliver therapeutics to the posterior segment. This space is accessible through a trans-scleral approach and blunt dissection of the adjacent scleral and choroidal tissues. However, despite recent commercial interest, there are few tools designed specifically to provide targeted delivery of therapeutics to a localised region within the suprachoroidal space. Therefore, we designed and prototyped a novel navigational catheter system for the targeted delivery of payloads within the suprachoroidal space. The system consists of a customised catheter tip designed to minimise blunt dissection stresses on neighbouring tissues, a mechanism for controlled catheter navigation, and a method for targeted delivery of large payloads. A customised

PurposeVeress needle (VN) insertion, if not correctly performed, could cause severe injuries to intra-abdominal organs and vessels. Therefore, cognitive and psychomotor skills training is needed. Virtual reality (VR) and haptic technologies have the potential to offer realistic simulations.MethodsWe developed a novel VR and haptic surgical simulator for VN insertion to teach trainees how to correctly puncture the abdominal wall, experiencing realistic tactile sensations throughout the simulation. The simulator allows for both procedural and realistic training. We released two different versions: the first using the OpenHaptics$$^{\text {TM}}$$TM(OH) Toolkit and the second exploiting CHAI3D. We evaluated the learning effect using different performance indexes (time to perform the procedure, error in insertion angle, number of undesired contacts with organs) in an insertion task for both experienced urologists and students.ResultsA general improvement of the chosen performance indexes was registered in the second repetition of the task for both groups. From the questionnaires, the simulator leveraging OH provides the trainee with a more precise haptic feedback, whereas the one exploiting CHAI3D allows them to perform the procedure more easily thanks to the better visualization of the virtual environment. The results proved that the participants appreciated both implementations, and the System Usability Scale (SUS) test resulted in a “good” usability.ConclusionThe haptics-based and VR simulator has shown the potential to be an important resource for the basic urological training in obtaining the pneumoperitoneum and improving the acquisition of the necessary psychomotor skills, allowing for extended and more effective training without compromising patient safety.

Purpose: Augmented reality-based image overlay of virtual bony spine anatomy can be projected onto real spinal anatomy using computer tomography-generated DICOM images acquired intraoperatively. The aim of the study was to develop a technique and assess the accuracy and feasibility of lumbar vertebrae pedicle instrumentation using augmented reality-assisted surgical navigation. Subjects and Methods: An augmented reality and artificial intelligence (ARAI)-assisted surgical navigation system was developed. The system consists of a display system which hovers over the surgical field and projects three-dimensional (3D) medical images corresponding with the patient's anatomy. The system was registered to the cadaveric spine using an optical tracker and arrays with reflective markers. The virtual image overlay from the ARAI system was compared to 3D generated images from intraoperative scans and used to percutaneously navigate a probe to the cortex at the corresponding pedicle starting point. Intraoperative scan was used to confirm the probe position. Virtual probe placement was compared to the actual probe position in the bone to determine the accuracy of the navigation system. Results: Four cadaveric thoracolumbar spines were used. The navigated probes were correctly placed in all attempted levels (n = 24 levels), defined as Zdichavsky type 1a, Ravi type I, and Gertzbein type 0. The virtual overlay image corresponded to the 3D generated image in all the tested levels. Conclusions: The ARAI surgical navigation system correctly and accurately identified the starting points at all the attempted levels. The virtual anatomy image overlay precisely corresponded to the actual anatomy in all the tested scenarios. This technology may lead more uniform outcomes between surgeons and decrease minimally invasive spine surgery learning curves.

IMPORTANCE: Complications that arise from phacoemulsification procedures can lead to worse visual outcomes. Real-time image processing with artificial intelligence tools can extract data to deliver surgical guidance, potentially enhancing the surgical environment. OBJECTIVE: To evaluate the ability of a deep neural network to track the pupil, identify the surgical phase, and activate specific computer vision tools to aid the surgeon during phacoemulsification cataract surgery by providing visual feedback in real time. DESIGN, SETTING, AND PARTICIPANTS: This cross-sectional study evaluated deidentified surgical videos of phacoemulsification cataract operations performed by faculty and trainee surgeons in a university-based ophthalmology department between July 1, 2020, and January 1, 2021, in a population-based cohort of patients. EXPOSURES: A region-based convolutional neural network was used to receive frames from the video source and, in real time, locate the pupil and in parallel identify the surgical phase being performed. Computer vision–based algorithms were applied according to the phase identified, providing visual feedback to the surgeon. MAIN OUTCOMES AND MEASURES: Outcomes were area under the receiver operator characteristic curve and area under the precision-recall curve for surgical phase classification and Dice score (harmonic mean of the precision and recall [sensitivity]) for detection of the pupil boundary. Network performance was assessed as video output in frames per second. A usability survey was administered to volunteer cataract surgeons previously unfamiliar with the platform. RESULTS: The region-based convolutional neural network model achieved area under the receiver operating characteristic curve values of 0.996 for capsulorhexis, 0.972 for phacoemulsification, 0.997 for cortex removal, and 0.880 for idle phase recognition. The final algorithm reached a Dice score of 90.23% for pupil segmentation and a mean (SD) processing speed of 97 (34) frames per second. Among the 11 cataract surgeons surveyed, 8 (72%) were mostly or extremely likely to use the current platform during surgery for complex cataract. CONCLUSIONS AND RELEVANCE: A computer vision approach using deep neural networks was able to pupil track, identify the surgical phase being executed, and activate surgical guidance tools. These results suggest that an artificial intelligence–based surgical guidance platform has the potential to enhance the surgeon experience in phacoemulsification cataract surgery. This proof-of-concept investigation suggests that a pipeline from a surgical microscope could be integrated with neural networks and computer vision tools to provide surgical guidance in real time.

Virtual reality (VR) surgical training and presurgical planning require the creation of 3D virtual models of patient anatomy from medical scans (e.g. CT or MRI). Real-time head tracking in VR applications allows users to navigate in the virtual anatomy from any 3D position and orientation. The process of interactively rendering highly detailed 3D volumetric data of anatomical models from a dynamically changing observer׳s perspective is extremely demanding for computational resources. We propose a parallel computing solution to this problem, involving a distributed volume graphics rendering system composed of multiple nodes concurrently working on different frames of the output stream, which are later integrated to form the final animation. In this scenario, it is important to consider frame losses generated by their out-of-order arrivals in the output sequence of 2D images. This paper presents a study of frame losses for a distributed graphics rendering system consisting of multiple GPU-based heterogeneous nodes running in a best-effort rendering scheme and applying an Alternate Frame Rendering technique. We describe a mathematical model of frame losses, as well as a performance evaluation comparing model predictions with experimental results.

Prostate cancer is the most common non-cutaneous cancer in America. Tumor detection involves non-invasive screening tests, but positive results must be confirmed by a prostate biopsy. About twelve random samples are obtained during the biopsy, which is a systematic procedure traditionally performed with trans-rectal ultrasound (TRUS) guidance to determine prostate location. Recently, methods of fusion between TRUS and preoperative MRI have been introduced in order to perform targeted biopsies aimed to reduce the number of samples to few suspicious areas. Since the TRUS displaces the prostate during the procedure, the preoperative MRI does not match patient anatomy. Therefore, complex MRI deformation algorithms are needed. However, despite the substantial increase in complexity and cost, there is no strong evidence that the TRUS-MRI fusion actually improves accuracy and surgical outcomes. This paper presents an innovative virtual reality surgical navigation system for performing targeted prostate biopsies, without the need of the uncomfortable TRUS. Both biopsy needle and patient anatomy are constantly tracked by an electromagnetic tracking system that provides their 3D position and orientation with respect to the surgical bed. Multiple fiducial markers are placed on the patient skin (at the iliac crest and pubic bone) during MRI scanning. Once in the operative room, the surgeon is presented a stereoscopic 3D volumetric rendering and multiple orthogonal views of the patient anatomy, as well as a virtual representation of the tracked needle. After a simple registration process between the MRI and the tracker coordinate system, the navigation system guides the needle insertion in the patient perineum through several anatomical layers towards the biopsy targets.

Background In this study, we evaluated the use of a part-task simulator with 3-dimensional and haptic feedback as a training tool for percutaneous spinal needle placement. Objective To evaluate the learning effectiveness in terms of entry point/target point accuracy of percutaneous spinal needle placement on a high-performance augmented-reality and haptic technology workstation with the ability to control the duration of computer-simulated fluoroscopic exposure, thereby simulating an actual situation. Methods Sixty-three fellows and residents performed needle placement on the simulator. A virtual needle was percutaneously inserted into a virtual patient's thoracic spine derived from an actual patient computed tomography data set. Results Ten of 126 needle placement attempts by 63 participants ended in failure for a failure rate of 7.93%. From all 126 needle insertions, the average error (15.69 vs 13.91), average fluoroscopy exposure (4.6 vs 3.92), and average individual performance score (32.39 vs 30.71) improved from the first to the second attempt. Performance accuracy yielded P = .04 from a 2-sample t test in which the rejected null hypothesis assumes no improvement in performance accuracy from the first to second attempt in the test session. Conclusion The experiments showed evidence (P = .04) of performance accuracy improvement from the first to the second percutaneous needle placement attempt. This result, combined with previous learning retention and/or face validity results of using the simulator for open thoracic pedicle screw placement and ventriculostomy catheter placement, supports the efficacy of augmented reality and haptics simulation as a learning tool.

Recent studies have shown that mental script-based rehearsal and simulation-based training improve the transfer of surgical skills in various medical disciplines. Despite significant advances in technology and intraoperative techniques over the last several decades, surgical skills training on neurosurgical operations still carries significant risk of serious morbidity or mortality. Potentially avoidable technical errors are well recognized as contributing to poor surgical outcome. Surgical education is undergoing overwhelming change, as a result of the reduction of work hours and current trends focusing on patient safety and linking reimbursement with clinical outcomes. Thus, there is a need for adjunctive means for neurosurgical training, which is a recent advancement in simulation technology. ImmersiveTouch is an augmented reality system that integrates a haptic device and a high-resolution stereoscopic display. This simulation platform uses multiple sensory modalities, re-creating many of the environmental cues experienced during an actual procedure. Modules available include ventriculostomy, bone drilling, percutaneous trigeminal rhizotomy, and simulated spinal modules such as pedicle screw placement, vertebroplasty, and lumbar puncture. We present our experience with the development of such augmented reality neurosurgical modules and the feedback from neurosurgical residents.

123 p. il. En la Argentina, la inflación es uno de los principales problemas de la economía. El presente proyecto aplica el proceso de minería de datos para encontrar patrones en variables económicas que permitan pronosticar la inflación. Para ello fue necesario obtener datos de economía, comprenderlos, prepararlos, elaborar el modelo de datos y analizar los resultados obtenidos. Con el objetivo de construir el modelo de datos se utilizaron redes neuronales y series de tiempo, de esta manera es posible realizar proyecciones de la inflación. Como resultado del proyecto se encuentran relaciones no lineales entre variables monetarias del sistema financiero asociadas al índice de precios al consumidor.

Aplicaciones de tiempo real como realidad virtual generan un flujo multimedia de tipo de máquina-humano que puede ser dividido tanto espacial como temporalmente para distribuir recursos de procesamiento, memoria o red. Este trabajo describe un protocolo para control de flujo de datos multimedia, donde su generación debe ser distribuida para incrementar el rendimiento. Este protocolo no describe la comunicación del flujo multimedia, sino solamente la comunicación de control para la generación de un único flujo multimedia entre múltiples nodos teniendo en cuenta un esquema de mejor esfuerzo. Para lograr estos objetivos se propone un protocolo de capa de aplicación, el cual utiliza UDP o UDP-lite en capa de transporte, IPv6 multicast en capa de red y Gigabit Ethernet con control de flujo en capa de enlace de datos.

Background We evaluated the use of a part-task simulator with 3D and haptic feedback as a training tool for a common neurosurgical procedure--placement of thoracic pedicle screws. Objective To evaluate the learning retention of thoracic pedicle screw placement on a high-performance augmented reality and haptic technology workstation. Methods Fifty-one fellows and residents performed thoracic pedicle screw placement on the simulator. The virtual screws were drilled into a virtual patient's thoracic spine derived from a computed tomography data set of a real patient. Results With a 12.5% failure rate, a 2-proportion z test yielded P = .08. For performance accuracy, an aggregate Euclidean distance deviation from entry landmark on the pedicle and a similar deviation from the target landmark in the vertebral body yielded P = .04 from a 2-sample t test in which the rejected null hypothesis assumes no improvement in performance accuracy from the practice to the test sessions, and the alternative hypothesis assumes an improvement. Conclusion The performance accuracy on the simulator was comparable to the accuracy reported in literature on recent retrospective evaluation of such placements. The failure rates indicated a minor drop from practice to test sessions, and also indicated a trend (P = .08) toward learning retention resulting in improvement from practice to test sessions. The performance accuracy showed a 15% mean score improvement and more than a 50% reduction in standard deviation from practice to test. It showed evidence (P = .04) of performance accuracy improvement from practice to test session.

Rapid advances in flexible display technologies and the benefits that they provide are promising enough to consider them for futuristic mobile devices. Current prototyping methods lack facilities to simulate such flexible touch screen displays and the interaction with them. In this paper, we present a technique that provides product developers a tool to interactively simulate products featuring flexible displays, using Augmented Reality and Haptics. This GPU-based algorithm is computationally inexpensive and efficient to deform a polygonal mesh in real time while maintaining an acceptable haptic feedback. The implementation of the algorithm has been found to be successful when applied to a variety of product simulations. This simulation tool can enhance or even replace traditional prototyping and facilitate testing of the prototype at various stages of the design cycle.

This paper focuses upon the research and development of a prototype dental simulator for training of periodontal procedures. By the use of virtual reality and haptics technology, the periodontal simulator allows trainees to learn performing diagnosis and treatment of periodontal diseases by visualizing a three-dimensional virtual human mouth and feeling real tactile sensations while touching the surface of teeth, gingiva, and calculi with virtual dental instruments. Since periodontics requires dentists to depend primarily on tactile sensations to perform diagnostic and surgical procedures, the use of haptics is unquestionably crucial for a realistic periodontal simulator. The haptics-based virtual reality periodontal training simulator has been validated by a experiment conducted by the College of Dentistry at University of Illinois at Chicago (UIC) with faculty members and dental students, which demonstrates the scientific contribution and usefulness of the simulator as a vital part of the curriculum of the Department of Periodontics at UIC.

Background With the decrease in the number of cerebral aneurysms treated surgically and the increase of complexity of those treated surgically, there is a need for simulation-based tools to teach future neurosurgeons the operative techniques of aneurysm clipping. Objective To develop and evaluate the usefulness of a new haptic-based virtual reality simulator in the training of neurosurgical residents. Methods A real-time sensory haptic feedback virtual reality aneurysm clipping simulator was developed using the ImmersiveTouch platform. A prototype middle cerebral artery aneurysm simulation was created from a computed tomographic angiogram. Aneurysm and vessel volume deformation and haptic feedback are provided in a 3-dimensional immersive virtual reality environment. Intraoperative aneurysm rupture was also simulated. Seventeen neurosurgery residents from 3 residency programs tested the simulator and provided feedback on its usefulness and resemblance to real aneurysm clipping surgery. Results Residents thought that the simulation would be useful in preparing for real-life surgery. About two-thirds of the residents thought that the 3-dimensional immersive anatomic details provided a close resemblance to real operative anatomy and accurate guidance for deciding surgical approaches. They thought the simulation was useful for preoperative surgical rehearsal and neurosurgical training. A third of the residents thought that the technology in its current form provided realistic haptic feedback for aneurysm surgery. Conclusion Neurosurgical residents thought that the novel immersive VR simulator is helpful in their training, especially because they do not get a chance to perform aneurysm clippings until late in their residency programs.

A high-performance solution offers faster 3D representation of users by avatars without compromising real-time interactivity.

Visualization methods of medical imagery based on volumetric data constitute a fundamental tool for medical diagnosis, training and pre-surgical planning. Often, large volume sizes and/or the complexity of the required computations present serious obstacles for reaching higher levels of realism and real-time performance. Performance and efficiency are two critical aspects in traditional algorithms based on complex lighting models. To overcome these problems, a volume rendering algorithm, PD-Render intra for individual networked nodes in a parallel distributed architecture with a single GPU per node is presented in this paper. The implemented algorithm is able to achieve photorealistic rendering as well as a high signal-tonoise ratio at interactive frame rates. Experiments show excellent results in terms of efficiency and performance for rendering medical volumes in real time. Fil: Perez Monte, Cristian Federico. Universidad Tecnológica Nacional. Facultad Regional Mendoza. Departamento de Electrónica. Grupo de Investigación Gridtics; Argentina. Universidad Tecnológica Nacional. Facultad Regional Mendoza. Departamento de Sistemas de Información. Laboratorio de Investigación en Cómputo Paralelo/Distribuido; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Informática. Laboratorio Investigación y Desarrollo en Inteligencia Computacional; Argentina Fil: Picolli, Fabiana. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Informática. Laboratorio Investigación y Desarrollo en Inteligencia Computacional; Argentina Fil: Luciano, Cristian. University of Illinois at Chicago. Department of Mechanical and Industrial Engineering; Estados Unidos Fil: Rizzi, Silvio. University of Illinois at Chicago. Department of Mechanical and Industrial Engineering; Estados Unidos Fil: Bianchini, German. Universidad Tecnológica Nacional. Facultad Regional Mendoza. Departamento de Sistemas de Información. Laboratorio de Investigación en Cómputo Paralelo/Distribuido; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza; Argentina Fil: Caymes Scutari, Paola Guadalupe. Universidad Tecnológica Nacional. Facultad Regional Mendoza. Departamento de Sistemas de Información. Laboratorio de Investigación en Cómputo Paralelo/Distribuido; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mendoza; Argentina

Volumetric datasets have become essential in virtual reality and haptics simulation for medical and surgical training. Technologies such as computed tomography (CT) and magnetic resonance imaging provide 3D scans of patient anatomy, from which 3D models can be generated to represent highly detailed and complex anatomical structures such as bone, organs, or muscle. Traditionally, 3D models have been represented as polygonal meshes, i.e., surfaces in 3D space consisting of multiple triangles. From the volumetric data, polygonal meshes are constructed using an isosurface extraction algorithm such as Marching Cubes [1]. Furthermore, mesh processing may be required in order to reduce the number of triangles in each model (decimation) and to obtain smooth surfaces. All these preprocessing stages often demand a fair amount of time to generate high quality models. Although methods to automate the segmentation and isosurface creation processes have been discussed in the literature [2], they still require considerable human intervention. Alternatively, anatomical 3D models can be displayed using direct volume rendering, which requires less human participation and minimum data preprocessing, generally at the expense of lower graphics frame rates. Combinations of scene graph managers [3,4] and haptics libraries [5] have been used in surgical simulations for graphics and haptics rendering of 3D models [6,7]. The goals of these simulations are simultaneous visualization of complex 3D models and tactile interaction with anatomy at interactive frame rates. While frame rates in the order of 30–60 Hz are acceptable for graphics rendering, the minimum required rate of 1 kHz for haptics rendering makes it a nontrivial problem when dealing with complex and highly detailed polygonal models. On the other hand, volume-based haptics techniques have proven themselves capable of generating force feedback from complex anatomies at interactive frame rates [8,9]. This paper presents a comparison of haptics rendering algorithms combined with polygonal graphics rendering within the framework of medical simulation. This evaluation seeks to assess the quality of the haptic feedback provided as well as identifying the best algorithm in terms of rendering time.

This is an excellent overview of the pros and cons of surgical VR techniques. In the Netherlands, it is concluded that training scenarios for complicated endoscopic procedures are lacking. A cultural shift in the teaching hospitals is thus needed both for trainers and trainees.[94] The authors also focus on the fact that so far it has not been proven that a virtual environment can improve neurosurgical training. The question “Why is that so?” is not fully answered! Limited dexterity will result in neurosurgical trainees not developing their skills to an extent that will convert them from novices into experienced surgeons.[89–91] Most importantly, however, all surgeons need to be able to reflect over how they are performing during operative procedures if they are to become true experts.[92] Moving into the topic “endoscopic surgery,” we also change our working space in many ways.[88] Most importantly, we change our normal working 3D space into a 2D space. Thereby we have to learn new ways of obtaining a 3D perception. Most literature on surgical VR techniques is dealing with multi-port endoscopy, where surgeons are working in an artificial, distended operative field. This is in contrast to neurosurgery, where only one endoscopic port is used. Models of removing gall bladders were among the first VR scenarios. While training with VR-simulators, there is a significant difference in the number of mistakes and speed between experienced and novice surgeons.[87] This fact cannot simply be transfered to the learning of endoscopy in neurosurgery. In endoscopic neurosurgery, using a single endoscope to both view and manipulate instruments in narrow spaces under the brain with very limited degrees of finger/hand movements makes a significant difference.[89] In real surgical life, sensing is a key point for neurosurgeons. For spatio/temporal skills, using the sense of touch is an important skill to learn and master. For technical reasons, haptics are most often not included in the VR systems on the market.[95] Verbal teaching of haptics is a challenging task. The range of haptic sensitivity varies from person to person, and possibly also from dominant to non-dominant hand in the same person. Bring a brain retractor into the field and demonstrate to your trainee how gentle your retraction of the brain is. How can the trainee sense what you are doing?[89,93] To the best of my knowledge, the topic of “how to learn to use a brain spatula” has never been introduced in neurosurgical training, not even in the present paper.No one mentions the fact that the trainee learns only how to use a spatula by watching his mentor in no way can the pressure-sensing of the spatula on the brain be transferred from trainer to trainee in the present operating room situations. We have therefore developed a Virtual Brain model using haptic feedback to develop different pressures of the retractor, and thus different deformations of the brain.[93] Now we can teach trainees how the true pressure equals the monitored pressure and the brain shape/deformations are correlated.[86] The neurosurgical VR training is thus different from training in conventional multi-port endoscopy. Neurosurgeons have to use VR systems that develop dexterity and transfer it into an automatic dexterity, whereby haptics are needed in the coming neurosurgical VR models.

(Tesis) Programa de Pedagogía para Licenciados El Colegio en el cual se realizó la práctica es el Arturo Prat, ubicado en la comuna de Talagante. Esta ciudad está distante 35 kilómetros al sur oriente de Santiago y el establecimiento está inmerso en el sector urbano de la comuna, cercano a importantes instituciones como la Comisaría de Carabineros, Centro de Salud Familiar Doctor Alberto Allende Jones, Parroquia Sagrado Corazón y otros establecimientos educacionales, uno de carácter particular subvencionado y tres de carácter municipal. El establecimiento cuenta con una matrícula de 332 alumnos, desde prekinder a cuarto año de enseñanza media. Hay un curso por nivel y se busca que haya matrícula 'reducida', con 30 alumnos máximo por curso para facilitar un buen ambiente de aprendizaje. El funcionamiento del establecimiento se desarrolla en media jornada para la educación preescolar y en jornada completa para la enseñanza básica y media.

Shameema Sikder,1 Jia Luo,2 P Pat Banerjee,2 Cristian Luciano,2 Patrick Kania,2 Jonathan C Song,1 Eman S Kahtani,3 Deepak P Edward,1,3 Abdul-Elah Al Towerki3 1Wilmer Eye Institute, Johns Hopkins University, Baltimore, MD, USA; 2College of Engineering, University of Illinois at Chicago, Chicago, IL, USA; 3King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia Purpose: To evaluate a haptic-based simulator, MicroVisTouch™, as an assessment tool for capsulorhexis performance in cataract surgery. The study is a prospective, unmasked, nonrandomized dual academic institution study conducted at the Wilmer Eye Institute at Johns Hopkins Medical Center (Baltimore, MD, USA) and King Khaled Eye Specialist Hospital (Riyadh, Saudi Arabia).Methods: This prospective study evaluated capsulorhexis simulator performance in 78 ophthalmology residents in the US and Saudi Arabia in the first round of testing and 40 residents in a second round for follow-up.Results: Four variables (circularity, accuracy, fluency, and overall) were tested by the simulator and graded on a 0–100 scale. Circularity (42%), accuracy (55%), and fluency (3%) were compiled to give an overall score. Capsulorhexis performance was retested in the original cohort 6months after baseline assessment. Average scores in all measured metrics demonstrated statistically significant improvement (except for circularity, which trended toward improvement) after baseline assessment. A reduction in standard deviation and improvement in process capability indices over the 6-month period was also observed.Conclusion: An interval objective improvement in capsulorhexis skill on a haptic-enabled cataract surgery simulator was associated with intervening operating room experience. Further work investigating the role of formalized simulator training programs requiring independent simulator use must be studied to determine its usefulness as an evaluation tool. Keywords: medical education, computer simulation, educational assessment, technology assessment, cataract surgery

Igor Kozak,1 Pat Banerjee,2 Jia Luo,2 Cristian Luciano21King Khaled Eye Specialist Hospital, Vitreoretinal Division, Riyadh, Kingdom of Saudi Arabia; 2College of Engineering, University of Illinois at Chicago, Chicago, IL, USAAbstract: Operative practice using surgical simulators has become a part of training in many surgical specialties, including ophthalmology. We introduce a virtual reality retina surgery simulator capable of integrating optical coherence tomography (OCT) scans from real patients for practicing vitreoretinal surgery using different pathologic scenarios.Keywords: optical coherence tomography