Do Disease Stories Need a Hero? Effects of Human Protagonists on a Narrative Visualization about Cerebral Small Vessel Disease

Authors use various media formats to convey disease information to a broad audience, from articles and videos to interviews or documentaries. These media often include human characters, such as patients or treating physicians, who are involved with the disease. While artistic media, such as hand-crafted illustrations and animations are used for health communication in many cases, our goal is to focus on data-driven visualizations. Over the last decade, narrative visualization has experienced increasing prominence, employing storytelling techniques to present data in an understandable way. Similar to classic storytelling formats, narrative medical visualizations may also take a human character-centered design approach. However, the impact of this form of data communication on the user is largely unexplored. This study investigates the protagonist's influence on user experience in terms of engagement, identification, self-referencing, emotional response, perceived credibility, and time spent in the story. Our experimental setup utilizes a character-driven story structure for disease stories derived from Joseph Campbell's Hero's Journey. Using this structure, we generated three conditions for a cerebral small vessel disease story that vary by their protagonist: (1) a patient, (2) a physician, and (3) a base condition with no human protagonist. These story variants formed the basis for our hypotheses on the effect of a human protagonist in disease stories, which we evaluated in an online study with 30 participants. Our findings indicate that a human protagonist exerts various influences on the story perception and that these also vary depending on the type of protagonist.publishedVersio

Enhanced Intraoperative Visualization for Brain Surgery: A Prototypic Simulated Scenario

Abstract: Due to the required high precision and reliability, image guidance is increasingly being adapted in neurosurgery Problem Medical navigation systems help physicians to establish correspondences between locations in an acquired patient dataset and the patient's physical body during navigated surgeries. This is highly advantageous in neurosurgery, where high precision is demanded. In a microscope-assisted surgery, however, this requires the surgeon to switch between the microscope and wall-mounted or computer displays. By incorporating augmented reality, it becomes possible to view patient data directly in the 3D context of the patient himself. This may provide an in-place insight into the patient body, which, for example, would help defining the entry point and the trajectory of a biopsy needle In this paper, we present a prototype for enhancing intraoperative visualization within the operating microscope, by augmenting the video stream with relevant patient data from different diagnostic and intraoperative imaging modalities. The advantage is a better localization of targeted lesions (e.g. tumor) and the protection of hidden risk structures like blood vessels and neural connections. The prototype includes the different components of a navigated procedure: tracking, calibration, registration, and rendering, which are described in the following section. Methods For our prototype, we implement a marker-based optical tracking system and use a tablet PC with a high resolution built-in camera to simulate the surgical microscope. A phantom model of the head simulates the patient. In the context of this paper, we refer to the tablet PC camera as the video camera and to the camera of the tracking system as the tracker camera. At a first step, the system cameras are calibrated to compute their intrinsic geometrical parameters. This is performed by capturing several photos of a special checkerboard pattern, with the tracker camera, from different Proceedings curac2010@MEDICA 12

Feature Lines for Illustrating Medical Surface Models: Mathematical Background and Survey

This paper provides a tutorial and survey for a specific kind of illustrative visualization technique: feature lines. We examine different feature line methods. For this, we provide the differential geometry behind these concepts and adapt this mathematical field to the discrete differential geometry. All discrete differential geometry terms are explained for triangulated surface meshes. These utilities serve as basis for the feature line methods. We provide the reader with all knowledge to re-implement every feature line method. Furthermore, we summarize the methods and suggest a guideline for which kind of surface which feature line algorithm is best suited. Our work is motivated by, but not restricted to, medical and biological surface models.Comment: 33 page

Hybrid Sample-based Surface Rendering

The performance of rasterization-based rendering on current GPUs strongly depends on the abilities to avoid overdraw and to prevent rendering triangles smaller than the pixel size. Otherwise, the rates at which highresolution polygon models can be displayed are affected significantly. Instead of trying to build these abilities into the rasterization-based rendering pipeline, we propose an alternative rendering pipeline implementation that uses rasterization and ray-casting in every frame simultaneously to determine eye-ray intersections. To make ray-casting competitive with rasterization, we introduce a memory-efficient sample-based data structure which gives rise to an efficient ray traversal procedure. In combination with a regular model subdivision, the most optimal rendering technique can be selected at run-time for each part. For very large triangle meshes our method can outperform pure rasterization and requires a considerably smaller memory budget on the GPU. Since the proposed data structure can be constructed from any renderable surface representation, it can also be used to efficiently render isosurfaces in scalar volume fields. The compactness of the data structure allows rendering from GPU memory when alternative techniques already require exhaustive paging

Interaction for Immersive Analytics

International audienceIn this chapter, we briefly review the development of natural user interfaces and discuss their role in providing human-computer interaction that is immersive in various ways. Then we examine some opportunities for how these technologies might be used to better support data analysis tasks. Specifically, we review and suggest some interaction design guidelines for immersive analytics. We also review some hardware setups for data visualization that are already archetypal. Finally, we look at some emerging system designs that suggest future directions

An Evaluation of Interaction Techniques for the Exploration of 3D-Illustrations

this paper we describe a practical study in which we set out to evaluate the major features of the Zoom Illustrator and to establish the value of each in facilitating access to 3dinformatio

Visualization of Anatomic Tree Structures with Convolution Surfaces

We present a method for visualizing anatomic tree structures, such as vasculature and bronchial trees based on clinical CT- or MR data. The vessel skeleton as well as the diameter information per voxel serve as input. Our method adheres to these data, while producing smooth transitions at branchings and closed, rounded ends by means of convolution surfaces. We discuss the filter design with respect to irritating bulges, unwanted blending and the correct visualization of the vessel diameter. Similar to related work our method is based on the assumption of a circular cross-section of vasculature. In contrast to other authors we employ implicit surfaces to achieve high quality visualization. The method has been applied to a large variety of anatomic trees and produces good results