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Cortical priming is an emerging strategy to enhance motor recovery after stroke, however, limited information exists on the neuromodulatory effects of lower limb movement-based priming to facilitate corticomotor excitability after stroke. In this study, we investigated the feasibility and effectiveness of game-based ankle movement priming using the DIG-I-PRIME™ on corticomotor excitability and motor performance in chronic stroke survivors.Nineteen stroke survivors participated in a 20-min session of game-based priming. A period of rest served as a control for the priming condition. Transcranial magnetic stimulation (TMS) was used to measure corticomotor excitability of the paretic and non-paretic tibialis anterior (TA) muscle representations. Motor performance was quantified by assessing the accuracy to track a sinusoidal target wave with paretic dorsiflexion and plantarflexion.Ipsilesional corticomotor excitability increased by 25% after game-based movement priming (Game-based ankle movement priming demonstrated a significant acute priming effect on the ipsilesional lower limb M1. These data provide preliminary evidence for the potential benefits of game-based priming to promote functional recovery after stroke.

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.

Virtual reality (VR) surgical training and presurgical planning require the creation of 3D virtual models of patient anatomy from medical scan data. 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. Parallel computing presents a solution to this problem, involving a distributed volume graphics rendering system composed of multiple nodes concurrently working on different portions of the output streaming, which are later integrated to form the final view. This paper presents a distributed graphics rendering system consisting of multiple GPU-based heterogeneous nodes running a best-effort rendering scheme. Experiments show promising results in terms of efficiency and performance for rendering medical volumes in real time.

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.

Haptics relates to the science of enabling “touch” of simulated objects in a virtual and controlled environment. It is an interdisciplinary field including computer science, engineering, physics, and human perception. Haptics is divided in three disciplines: human, machine, and computer haptics. Each haptic device is composed of electromechanical sensors and actuators that enable tactile feedback by interacting with virtual objects. Current examples of haptic devices include exoskeletal and stand-alone devices that are used on different medical training simulators.

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.

This poster presents a part-task haptic simulator for ophthalmic surgical training developed for the MicrovisTouch simulation platform. This ophthalmic surgical simulator provides both realistic 3D visualization and haptic feedback. Trainees are able to learn interacting with a physics-based dynamic virtual eye model and receiving tactile feedback by handling virtual instruments while simulating a series of surgical tasks and exercises, including micro-dexterity and corneal incision. A pilot study was conducted on the micro-dexterity to measure its effectiveness to evaluate trainees' skills performing precise instrument motion required for ophthalmic surgical procedures.

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.