CAD-CAM Implants in Esthetic and Reconstructive Craniofacial Surgery

In the reconstruction of complex craniofacial malformations CAD-CAM procedures could help generating alloplastic implants to achieve almost optimal esthetic results. Complementary to the existing CAD-CAM techniques in the cranial vault region or modeling procedures in unilateral defects, these techniques are introduced to bilaterally affected skulls in esthetic reconstructive surgery. Surgery could thus become less invasive and results more predictable. A tool chain is shown to generate such implants on scientific basis. 3D cephalometric analysis is performed and the implants are designed according to the individual pathology. Besides the planning of implants on the basis of 3D-landmarks, future implant design is supposed to be performed with the help of a craniofacial library taken from CT-scans of unaffected skulls

The Role of Computational Fluid Dynamics in the Management of Unruptured Intracranial Aneurysms: A Clinicians' View

Objective. The importance of hemodynamics in the etiopathogenesis of intracranial aneurysms (IAs) is widely accepted. Computational fluid dynamics (CFD) is being used increasingly for hemodynamic predictions. However, alogn with the continuing development and validation of these tools, it is imperative to collect the opinion of the clinicians. Methods. A workshop on CFD was conducted during the European Society of Minimally Invasive Neurological Therapy (ESMINT) Teaching Course, Lisbon, Portugal. 36 delegates, mostly clinicians, performed supervised CFD analysis for an IA, using the @neuFuse software developed within the European project @neurIST. Feedback on the workshop was collected and analyzed. The performance was assessed on a scale of 1 to 4 and, compared with experts' performance. Results. Current dilemmas in the management of unruptured IAs remained the most important motivating factor to attend the workshop and majority of participants showed interest in participating in a multicentric trial. The participants achieved an average score of 2.52 (range 0–4) which was 63% (range 0–100%) of an expert user. Conclusions. Although participants showed a manifest interest in CFD, there was a clear lack of awareness concerning the role of hemodynamics in the etiopathogenesis of IAs and the use of CFD in this context. More efforts therefore are required to enhance understanding of the clinicians in the subject

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calculus for stencils on arbitrary grids with applications to parallel PDE solutio

Proceedings of the 17 th GAMM-Seminar Leipzig 2001, pp. 1–28 A Generic Toolbox for the Grid Craftsman

Universally reusable tools for grid management tasks are scarce. We identify coupling of algorithms to data structures as main obstacle for reuse, and show how to overcome the difficulties by using generic programming. After introducing an abstract kernel of grid functionality, we present some universal generic grid tools based on that kernel which are usable for arbitrary grid data structures. For evaluating the approach, we describe how to leverage these tools in order to set up a framework for hybrid grid generation. Finally, we show how to use generic components with existing grid data structures, and discuss the efficiency of generic grid tools, which is overall quite satisfying. 1 The Grid Craftsman’s Old Tools Computational scientists who are in charge of constructing and processing grids for scientific applications are in need of a vast amount of different support tools. First spring to mind basic tasks, such as reading and writing grids from and to files in different formats, including compressed ones, converting between variou

Generic Components for Grid Data Structures and Algorithms with C++

Grids are fundamental data structures for representing geometric structures or their subdivisions. We propose a strategy for decoupling algorithms working on grids from the details of grid representations, using a generic programming approach in C++. Functionality of grid data structures is captured by a small set of primitives, divided into combinatorial and geometric ones. Special attention is paid to the generic implementation of grid functions, which correspond to the notion of mappings from grid elements (e. g. vertices) to entities of a given type. Experiments indicate that the overhead of the generic formulation is low and can be completely eliminated in some cases. 1 Introduction Representation of spatial or planar geometric structures is central to many application domains, such as computational geometry, geometric modeling, geographical information systems (GIS), and computational simulation by numerical solution of partial di#erential equations (PDEs). Spatial structures a..

universally usable geometric components

structure abstractions Geometric functionality is crucial for a variety of application domains, including computational mechanics. Typically, geometric tasks are embedded into a larger problem frame. Due to the diversity of tasks, geometric tools must often be combined to achieve the desired solution. As implementing geometric algorithms is difficult and time-consuming, reusing them is highly desirable. Unfortunately, traditional implementations are intimately tied to the underlying representations of the geometric data, and hence are not directly usable in a different context. Conventional approaches to implementing geometric tools are thus limited to copying the data via an API (or to a file), and calling an external routine (or application) application implementing the desired functionality or even implementing an ad-hoc solution, and have obvious drawbacks in terms of efficiency, composability, scalability or quality. Here, we present a radically different approach, concentrating on the case of algorithms working on cellular structures, for example meshes (tesselations, grids) of surfaces and solids. Exploiting the common underlying mathematical structure we define an abstract interface capturing this mathematical notion. Algorithms are implemented generically on top of this interface, thus making the implementation