On Visualizing Branched Surface: an Angle/Area Preserving Approach

The techniques of surface deformation and mapping are useful tools for the visualization of medical surfaces, especially for highly undulated or branched surfaces. In this thesis, two algorithms are presented for flattened visualizations of multi-branched medical surfaces, such as vessels. The first algorithm is an angle preserving approach, which is based on conformal analysis. The mapping function is obtained by minimizing two Dirichlet functionals. On a triangulated representation of vessel surfaces, this algorithm can be implemented efficiently using a finite element method. The second algorithm adjusts the result from conformal mapping to produce a flattened representation of the original surface while preserving areas. It employs the theory of optimal mass transport via a gradient descent approach. A new class of image morphing algorithms is also considered based on the theory of optimal mass transport. The mass moving energy functional is revised by adding an intensity penalizing term, in order to reduce the undesired "fading" effects. It is a parameter free approach. This technique has been applied on several natural and medical images to generate in-between image sequences.Ph.D.Allen Tannenbaum Committee Chair Anthony J. Yezzi, Committee Member; James Gruden, Committee Member; May D. Wang, Committee Member; Oskar Skrinjar, Committee Membe

Angle-preserving mappings for the visualization of multi-branched vessels

©2002 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or distribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder.DOI: 10.1109/ICIP.2002.1040108We employ a conformal mapping technique to flatten tubular structures with multi-branches for visualization of MRA and CT volumetric vessel imagery. This may be used for the study of possible vessel pathology or virtual colonoscopy for polyp detection. The method is based on a discrete Laplace-Beltrami operator to flatten a tubular surface onto a planar polygonal region in an angle-preserving manner. A thinned pruned medial surface (or skeleton) is used for the vessel partition

Rapid development of applications for the interactive visual analysis of multimodal medical data

Multimodale medizinische Volumendaten gewinnen zunehmend an Verbreitung. Wir diskutieren verschiedene interaktive Applikationen welche den Nutzer bei der Analyse dieser Daten unterstützen. Alle Applikationen basieren auf Erweiterungen des Voreen Frameworks, welche ebenfalls in dieser Dissertation diskutiert werden. With multimodal volumetric medical data sets becoming more common due to the increasing availability of scanning hardware, software for the visualization and analysis of such data sets needs to become more efficient as well in order to prevent overloading the user with data. This dissertation presents several interactive techniques for the visual analysis of medical volume data. All applications are based on extensions to the Voreen volume rendering framework, which we will discuss first. Since visual analysis applications are interactive by definition, we propose a general-purpose navigation technique for volume data. Next, we discuss our concepts for the interactive planning of brain tumor resections. Finally, we present two systems designed to work with images of vasculature. First, we discuss an interactive vessel segmentation system enabling an efficient, visually supported workflow. Second, we propose an application for the visual analysis of PET tracer uptake along vessels