DUNEuro-A software toolbox for forward modeling in bioelectromagnetism.

Accurate and efficient source analysis in electro- and magnetoencephalography using sophisticated realistic head geometries requires advanced numerical approaches. This paper presents DUNEuro, a free and open-source C++ software toolbox for the numerical computation of forward solutions in bioelectromagnetism. Building upon the DUNE framework, it provides implementations of modern fitted and unfitted finite element methods to efficiently solve the forward problems of electro- and magnetoencephalography.

The Unfitted Discontinuous Galerkin Method for Solving the EEG Forward Problem.

Objective: The purpose of this study is to introduce and evaluate the unfitted discontinuous Galerkin finite element method (UDG-FEM) for solving the electroencephalography (EEG) forward problem.

Methods: This new approach for source analysis does not use a geometry conforming volume triangulation, but instead uses a structured mesh that does not resolve the geometry. The geometry is described using level set functions and is incorporated implicitly in its mathematical formulation.

Use of vascular and non-vascular models for the assessment of temperature distribution during induced hyperthermia.

We developed a three-dimensional thermal model in which convective heat transfer in a human extremity is explicitly quantified by taking into account the physical details of the vascular system. The spatial pattern in the arterial, venous and tissue temperature is computed during hyperthermia treatment. As such a complex vascular model is not generally applicable, a comparative study of the results of simpler, substitutional, non-vascular concepts applied to hyperthermia was carried out.

Efficiency function: improvement of classical bioheat approach.

In view of the complex vascular architecture and the intricate physical heat transfer processes in the human body, convective heat transfer via the blood is generally described by simple substitutional processes ("non-vascular models"). The classical "bioheat" approach of Pennes (J. Appl.

Estimation of the thermal effect of blood flow in a branching countercurrent network using a three-dimensional vascular model.

A three-dimensional thermal model is presented in which convective heat transfer is defined in terms of the physical details of the vascular system. The convective heat exchange between prearteriole and postvenule vessels and the tissue across the vessel walls is calculated explicitly without using shape factors. Conduction in x-, y-, and z-direction is considered.

[Delay of retinal fluorescence as a death criterion].

Retinal fluoroscopy with measurement of the arm to retina circulation time can be used to evaluate the blood supply to the brain. When the brain tissue suffers from ischaemia as a result of circulatory failure, the arm to retina circulation time will be prolonged. Sixteen patients in deep coma resulting from serious cerebral disease were examined to verify cerebral ischaemia.