Methods Inf Med 2007; 46(06): 646-654
DOI: 10.3414/ME0427
Original Article
Schattauer GmbH

Detection of Phase Singularities in Triangular Meshes

L. J. Rantner
1   Institute of Biomedical Engineering, University for Health Sciences, Medical Informatics and Technology (UMIT), Hall in Tirol, Austria
2   Department for Cardiology, Medical University Innsbruck, Innsbruck, Austria
,
L. Wieser
1   Institute of Biomedical Engineering, University for Health Sciences, Medical Informatics and Technology (UMIT), Hall in Tirol, Austria
,
M. C. Stühlinger
2   Department for Cardiology, Medical University Innsbruck, Innsbruck, Austria
,
F. Hintringer
2   Department for Cardiology, Medical University Innsbruck, Innsbruck, Austria
,
B. Tilg
1   Institute of Biomedical Engineering, University for Health Sciences, Medical Informatics and Technology (UMIT), Hall in Tirol, Austria
,
G. Fischer
1   Institute of Biomedical Engineering, University for Health Sciences, Medical Informatics and Technology (UMIT), Hall in Tirol, Austria
› Author Affiliations
Further Information

Publication History

Received: 12 May 2006

Accepted: 27 November 2006

Publication Date:
12 January 2018 (online)

Summary

Objectives : Phase singularities have become a key marker in animal and computer models of atrial and ventricular fibrillation. However, existing algorithms for the automatic detection of phase singularities are limited to regular, quadratic mesh grids. We present an algorithm to automatically and exactly detect phase singularities in triangular meshes.

Methods : For each node an oriented path inscribing the node with one unit of spatial discretization is identified. At each time step the phase information is calculated for all nodes. The so-called topological charge is also computed for each node. A non-zero (± 2π) charge is obtained for all nodes with a path enclosing a phase singularity. Thus all charged nodes belonging to the same phase singularity have to be clustered.

Results : With the use of the developed algorithm, phase singularities can be detected in triangular meshes with an accuracy of below 0.2 mm – independent of the type of membrane kinetics used.

Conclusions : With the possibility to detect phase singularities automatically and exactly, important quantitative data on cardiac fibrillation can be gained.

 
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