Towards markerless orthopaedic navigation with intuitive Optical See-through Head-mounted displays

The potential of image-guided orthopaedic navigation to improve surgical outcomes has been well-recognised during the last two decades. According to the tracked pose of target bone, the anatomical information and preoperative plans are updated and displayed to surgeons, so that they can follow the guidance to reach the goal with higher accuracy, efficiency and reproducibility. Despite their success, current orthopaedic navigation systems have two main limitations: for target tracking, artificial markers have to be drilled into the bone and calibrated manually to the bone, which introduces the risk of additional harm to patients and increases operating complexity; for guidance visualisation, surgeons have to shift their attention from the patient to an external 2D monitor, which is disruptive and can be mentally stressful. Motivated by these limitations, this thesis explores the development of an intuitive, compact and reliable navigation system for orthopaedic surgery. To this end, conventional marker-based tracking is replaced by a novel markerless tracking algorithm, and the 2D display is replaced by a 3D holographic Optical see-through (OST) Head-mounted display (HMD) precisely calibrated to a user's perspective. Our markerless tracking, facilitated by a commercial RGBD camera, is achieved through deep learning-based bone segmentation followed by real-time pose registration. For robust segmentation, a new network is designed and efficiently augmented by a synthetic dataset. Our segmentation network outperforms the state-of-the-art regarding occlusion-robustness, device-agnostic behaviour, and target generalisability. For reliable pose registration, a novel Bounded Iterative Closest Point (BICP) workflow is proposed. The improved markerless tracking can achieve a clinically acceptable error of 0.95 deg and 2.17 mm according to a phantom test. OST displays allow ubiquitous enrichment of perceived real world with contextually blended virtual aids through semi-transparent glasses. They have been recognised as a suitable visual tool for surgical assistance, since they do not hinder the surgeon's natural eyesight and require no attention shift or perspective conversion. The OST calibration is crucial to ensure locational-coherent surgical guidance. Current calibration methods are either human error-prone or hardly applicable to commercial devices. To this end, we propose an offline camera-based calibration method that is highly accurate yet easy to implement in commercial products, and an online alignment-based refinement that is user-centric and robust against user error. The proposed methods are proven to be superior to other similar State-of- the-art (SOTA)s regarding calibration convenience and display accuracy. Motivated by the ambition to develop the world's first markerless OST navigation system, we integrated the developed markerless tracking and calibration scheme into a complete navigation workflow designed for femur drilling tasks during knee replacement surgery. We verify the usability of our designed OST system with an experienced orthopaedic surgeon by a cadaver study. Our test validates the potential of the proposed markerless navigation system for surgical assistance, although further improvement is required for clinical acceptance.Open Acces

Cerebral Circulation

Diagnostics and diseases related to the cerebrovascular system are constantly evolving and updating. 3D augmented reality or quantification of cerebral perfusion are becoming important diagnostic tools in daily practice and the role of the cerebral venous system is being constantly revised considering new theories such as that of “the glymphatic system.” This book provides updates on models, diagnosis, and treatment of diseases of the cerebrovascular system

Advances in Minimally Invasive Surgery

The minimally invasive approach in medicine is one of the most common areas of interest in surgery.Advances in Minimally Invasive Surgery describes the latest trends, indications, techniques, and approaches in minimally invasive surgery. It provides step-by-step instructions for both routine and diagnostic procedures via illustrations and video collection

Medical Robotics

The first generation of surgical robots are already being installed in a number of operating rooms around the world. Robotics is being introduced to medicine because it allows for unprecedented control and precision of surgical instruments in minimally invasive procedures. So far, robots have been used to position an endoscope, perform gallbladder surgery and correct gastroesophogeal reflux and heartburn. The ultimate goal of the robotic surgery field is to design a robot that can be used to perform closed-chest, beating-heart surgery. The use of robotics in surgery will expand over the next decades without any doubt. Minimally Invasive Surgery (MIS) is a revolutionary approach in surgery. In MIS, the operation is performed with instruments and viewing equipment inserted into the body through small incisions created by the surgeon, in contrast to open surgery with large incisions. This minimizes surgical trauma and damage to healthy tissue, resulting in shorter patient recovery time. The aim of this book is to provide an overview of the state-of-art, to present new ideas, original results and practical experiences in this expanding area. Nevertheless, many chapters in the book concern advanced research on this growing area. The book provides critical analysis of clinical trials, assessment of the benefits and risks of the application of these technologies. This book is certainly a small sample of the research activity on Medical Robotics going on around the globe as you read it, but it surely covers a good deal of what has been done in the field recently, and as such it works as a valuable source for researchers interested in the involved subjects, whether they are currently “medical roboticists” or not

A Haptic Study to Inclusively Aid Teaching and Learning in the Discipline of Design

Designers are known to use a blend of manual and virtual processes to produce design prototype solutions. For modern designers, computer-aided design (CAD) tools are an essential requirement to begin to develop design concept solutions. CAD, together with augmented reality (AR) systems have altered the face of design practice, as witnessed by the way a designer can now change a 3D concept shape, form, color, pattern, and texture of a product by the click of a button in minutes, rather than the classic approach to labor on a physical model in the studio for hours. However, often CAD can limit a designer’s experience of being ‘hands-on’ with materials and processes. The rise of machine haptic1 (MH) tools have afforded a great potential for designers to feel more ‘hands-on’ with the virtual modeling processes. Through the use of MH, product designers are able to control, virtually sculpt, and manipulate virtual 3D objects on-screen. Design practitioners are well placed to make use of haptics, to augment 3D concept creation which is traditionally a highly tactile process. For similar reasoning, it could also be said that, non-sighted and visually impaired (NS, VI) communities could also benefit from using MH tools to increase touch-based interactions, thereby creating better access for NS, VI designers. In spite of this the use of MH within the design industry (specifically product design), or for use by the non-sighted community is still in its infancy. Therefore the full benefit of haptics to aid non-sighted designers has not yet been fully realised. This thesis empirically investigates the use of multimodal MH as a step closer to improving the virtual hands-on process, for the benefit of NS, VI and fully sighted (FS) Designer-Makers. This thesis comprises four experiments, embedded within four case studies (CS1-4). Case study 1and2 worked with self-employed NS, VI Art Makers at Henshaws College for the Blind and Visual Impaired. The study examined the effects of haptics on NS, VI users, evaluations of experience. Case study 3 and4, featuring experiments 3 and4, have been designed to examine the effects of haptics on distance learning design students at the Open University. The empirical results from all four case studies showed that NS, VI users were able to navigate and perceive virtual objects via the force from the haptically rendered objects on-screen. Moreover, they were assisted by the whole multimodal MH assistance, which in CS2 appeared to offer better assistance to NS versus FS participants. In CS3 and 4 MH and multimodal assistance afforded equal assistance to NS, VI, and FS, but haptics were not as successful in bettering the time results recorded in manual (M) haptic conditions. However, the collision data between M and MH showed little statistical difference. The thesis showed that multimodal MH systems, specifically used in kinesthetic mode have enabled human (non-disabled and disabled) to credibly judge objects within the virtual realm. It also shows that multimodal augmented tooling can improve the interaction and afford better access to the graphical user interface for a wider body of users

Studies in the image of the Madonna lactans in late medieval and Renaissance Italy.

This dissertation is an analysis of Italian late medieval and Renaissance peoples’ response to the Madonna lactans image. Although the images that comprise this type are similar in that Mary holds Christ at her breast, they vary widely in iconography and context. We shall use reception and response theory to determine how the image functioned for spectators. Determining how different groups responded to the motif is facilitated by applying an interpretive community model. Hence a group’s interpretive principles connect these communities and inform their reception of the image. We argue that although context and communities are diverse, most people believed the image to be a conduit to the divine. Our study is divided into four chapters covering a late medieval through Renaissance history of breastfeeding, devotion, the motif as an altarpiece, and reception by Renaissance people. Chapter one gives a historical overview of the advice concerning breastfeeding to which medievals were subjected. In light of sacerdotal advice, we argue that the Church used the image to promote maternal feeding. We also consider wet nurses as a community and audience. Chapter two draws on social and historical inquiries to explore public and private devotion. We highlight the Madonna lactans as an intercessor. While chapter one and two provide a historical and social foundation, the next two chapters consider different interpretive communities’ experiential viewing. Chapter three argues that the late medieval altarpiece image was more than an aesthetic illusion for churchgoers, finding that the image was believed to have sacramental value. Theories about medieval vision are applied to viewing religious rites with images. Chapter four delves into several communities’ interpretive principles. First, in light of its increased naturalism, we argue against a prurient reading of the image by applying scientific studies, an iconographic analysis, and period laws. Second, we find that nuns perceived the image to be a means to intimacy with Christ. One nun’s desire for contemplation before the image was so ardent, she drew it for her private edification, at great personal risk. Finally, we argue that when the viewer held the interpretive power, lay people embraced the image’s intercessory message

Choreographic and Somatic Approaches for the Development of Expressive Robotic Systems

As robotic systems are moved out of factory work cells into human-facing environments questions of choreography become central to their design, placement, and application. With a human viewer or counterpart present, a system will automatically be interpreted within context, style of movement, and form factor by human beings as animate elements of their environment. The interpretation by this human counterpart is critical to the success of the system's integration: knobs on the system need to make sense to a human counterpart; an artificial agent should have a way of notifying a human counterpart of a change in system state, possibly through motion profiles; and the motion of a human counterpart may have important contextual clues for task completion. Thus, professional choreographers, dance practitioners, and movement analysts are critical to research in robotics. They have design methods for movement that align with human audience perception, can identify simplified features of movement for human-robot interaction goals, and have detailed knowledge of the capacity of human movement. This article provides approaches employed by one research lab, specific impacts on technical and artistic projects within, and principles that may guide future such work. The background section reports on choreography, somatic perspectives, improvisation, the Laban/Bartenieff Movement System, and robotics. From this context methods including embodied exercises, writing prompts, and community building activities have been developed to facilitate interdisciplinary research. The results of this work is presented as an overview of a smattering of projects in areas like high-level motion planning, software development for rapid prototyping of movement, artistic output, and user studies that help understand how people interpret movement. Finally, guiding principles for other groups to adopt are posited.Comment: Under review at MDPI Arts Special Issue "The Machine as Artist (for the 21st Century)" http://www.mdpi.com/journal/arts/special_issues/Machine_Artis