Augmented reality guided condylectomy

An accurate transfer of a 3D virtual planned proportional condylectomy to the patient is challenging due to the limited surgical access. A new clinical workflow that uses augmented reality to assist a condylectomy is presented step-by-step. This AR-based approach has the potential to be implemented in the clinical setting routinely.     

A new AR interaction paradigm for collaborative teleassistance system: the POA

In this paper, we propose a prototype of a (collaborative) teleassistance system for mechanical repairs based on Augmented Reality (AR). This technology is generally used to implement specific assistance applications for users, which consist of providing all the information, known as augmentations, required to perform a task. For teletransmission applications, operators are equipped with a wearable computer and a technical support expert can accurately visualize what the operator sees thanks to the teletransmission of the corresponding video stream. Within the framework of remote communication, our aim is to foster collaboration, especially informal collaboration, between the operator and the expert in order to make teleassistance easier and more efficient. To do this we rely on classical repair technologies and on collaborative systems to introduce a new human-machine interaction: the Picking Outlining Adding interaction (POA interaction). With this new interaction paradigm, technical information is provided by directly Picking, Outlining and Adding information to an item in an operator’s video stream.     

Interactive virtual assembling in augmented reality

In this paper, a computer-aided methodology based on augmented reality to manipulate and interactively assemble virtual objects is presented. The developed system, based on both hardware and software implementation, allows the user to be immersed in an augmented scene (real world and virtual objects) by means of an head-mounted display and interact with the virtual components using a glove with sensors. The author presents the implementation of the system facing the problems concerning the interpretation of user’s intent to grasp and move the objects and the computer-aided assembly based on a novel approach concerning active features dynamic recognition. An example of implementation is herein reported and discussed.     

Supporting mandibular resection with intraoperative navigation utilizing augmented reality technology – A proof of concept study

ObjectiveThe aim of this study was to compare the accuracy of simulated mandibular osteotomies performed with cutting guides and two different intraoperative navigation systems based on simple (sAR) and navigated (nAR) augmented reality technology.Material and methodsA total of 126 osteotomies were performed on 21 identical mandible models according to a prespecified virtual surgery plan. The data from postoperative computed tomography (CT) images were fused with preoperative CT scans to objectively compare the outcomes, i.e. angular deviations from the osteotomy trajectory (°) and displacement of two control points (mm).ResultsOsteotomies performed with cutting guides turned out to be the most accurate, with mean angular deviation of 4.94 ± 4.62° and mean control point displacement of 1.65 ± 0.88 mm. Mandibular osteotomies assisted with sAR and nAR were less accurate in terms of mean angular deviations (5.34 ± 3.67° and 7.14 ± 5.19°, respectively) and control point displacements (1.79 ± 0.94 mm and 2.41 ± 1.34 mm, respectively).ConclusionOur findings imply that in future, AR-based intraoperative navigation systems may find application in everyday clinical practice. Although AR technology still requires some improvements, it can already be used for presentation of digital navigation data, enhancing surgeon's awareness and hand-eye coordination during mandibular resection and reconstruction procedures.     

Augmented reality in dentistry: a current perspective

Augmentation reality technology offers virtual information in addition to that of the real environment and thus opens new possibilities in various fields. The medical applications of augmentation reality are generally concentrated on surgery types, including neurosurgery, laparoscopic surgery and plastic surgery. Augmentation reality technology is also widely used in medical education and training. In dentistry, oral and maxillofacial surgery is the primary area of use, where dental implant placement and orthognathic surgery are the most frequent applications. Recent technological advancements are enabling new applications of restorative dentistry, orthodontics and endodontics. This review briefly summarizes the history, definitions, features, and components of augmented reality technology and discusses its applications and future perspectives in dentistry.     

三维可视化引导放疗摆位系统的研发及临床应用

目的 开发一种三维可视化技术辅助放疗患者摆位，并对比分析其在乳腺和盆腔放疗中与传统摆位方法的差异。方法 选取2020年6月至2021年4月常州第二人民医院40例放疗患者作为研究对象，其中乳腺、盆腔患者各20例。利用患者定位CT数据进行三维可视化重建，并将三维可视化模型与真实治疗环境融合，通过交互操作使得三维可视化模型位于加速器等中心点，并以此为依据进行实际患者的摆位。每例患者每周先进行传统摆位、再进行三维可视化引导放疗摆位，分3周采集，所有患者共240次摆位数据，以锥形束CT （CBCT）引导的摆位作为金标准进行比较。结果 乳腺患者和盆腔患者三维可视化引导摆位x、y、z轴摆位误差绝对值后分别为（1.92±1.23）、（2.04±1.16）、（1.77±1.37） mm和（2.07±1.08）、（1.33±0.88）、（1.99±1.25） mm，各轴精度较传统摆位分别提高了38.83%、52.40%、33%和36.84%、54.04%、52.58%，y、z轴上的差异具有统计学意义（t=2.956~5.734，P<0.05）。同时，对于乳腺患者，两种摆位方法y方向误差分布具有统计学意义（χ²=7.481，P<0.05），对于盆腔患者，两种摆位方法在各轴的误差分布差异均有统计学意义（χ²=5.900、6.415、7.200，P<0.05）。结论 三维可视化技术引导放疗摆位方法有效提高了乳腺和盆腔患者的摆位精度，具有潜在的临床应用价值。     

Augmented Reality Farm MAPPER Development: Lessons Learned from an App Designed to Improve Rural Emergency Response

Fire departments have right-of-entry to most commercial industrial sites and preemptively map them to identify the onsite resources and hazards they need to promptly and safely respond to an emergency event. This is not the case for private farms. Emergency responders are blind to resources and hazards prior to arrival and must spend critical minutes locating them during an emergency response at a farm location. The original 2013 Farm Mapping to Assist, Protect and Prepare Emergency Responders (Farm MAPPER) project was undertaken to develop a method to give emergency responders an up-to-date view of on-farm hazard information to safely and efficiently conduct emergency response activities on private agricultural operations. In 2017, an augmented reality version of Farm MAPPER was developed to combine the technological advantages of geographic information system-based data points with a heads-up display and graphical overlay of superimposed hazard imagery and informative icons. The development and testing of this iOS- and Android-ready prototype uncovered lessons learned applicable to other mobile-based apps targeting farmers, ranchers, and rural populations faced with limited or inconsistent mobile internet connectivity.     

Multisensory integration across exteroceptive and interoceptive domains modulates self-experience in the rubber-hand illusion

Identifying with a body is central to being a conscious self. The now classic “rubber hand illusion” demonstrates that the experience of body-ownership can be modulated by manipulating the timing of exteroceptive (visual and tactile) body-related feedback. Moreover, the strength of this modulation is related to individual differences in sensitivity to internal bodily signals (interoception). However the interaction of exteroceptive and interoceptive signals in determining the experience of body-ownership within an individual remains poorly understood. Here, we demonstrate that this depends on the online integration of exteroceptive and interoceptive signals by implementing an innovative “cardiac rubber hand illusion” that combined computer-generated augmented-reality with feedback of interoceptive (cardiac) information. We show that both subjective and objective measures of virtual-hand ownership are enhanced by cardio-visual feedback in-time with the actual heartbeat, as compared to asynchronous feedback. We further show that these measures correlate with individual differences in interoceptive sensitivity, and are also modulated by the integration of proprioceptive signals instantiated using real-time visual remapping of finger movements to the virtual hand. Our results demonstrate that interoceptive signals directly influence the experience of body ownership via multisensory integration, and they lend support to models of conscious selfhood based on interoceptive predictive coding.