gms | German Medical Science

57th Annual Meeting of the German Society of Neurosurgery
Joint Meeting with the Japanese Neurosurgical Society

German Society of Neurosurgery (DGNC)

11 - 14 May, Essen

Development of an aneurysm model in order to improve computational flow dynamic analyses

Entwicklung eines Glasaneurysmamodells zur Verbesserung der computational flow dynamic analyses

Meeting Abstract

  • corresponding author C. Doenitz - Klinik und Poliklinik für Neurochirurgie, Universitätsklinikum Regensburg
  • R. Rothoerl - Klinik und Poliklinik für Neurochirurgie, Universitätsklinikum Regensburg
  • M. Amendt - Labor für Windkanal und Strömungstechnik, Regensburg
  • S. Laemmlein - Labor für Windkanal und Strömungstechnik, Regensburg
  • A. Brawanski - Klinik und Poliklinik für Neurochirurgie, Universitätsklinikum Regensburg

Deutsche Gesellschaft für Neurochirurgie. Japanische Gesellschaft für Neurochirurgie. 57. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie e.V. (DGNC), Joint Meeting mit der Japanischen Gesellschaft für Neurochirurgie. Essen, 11.-14.05.2006. Düsseldorf, Köln: German Medical Science; 2006. DocP 10.155

The electronic version of this article is the complete one and can be found online at:

Published: May 8, 2006

© 2006 Doenitz et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.



Objective: Over the past years there is an increasing number of studies dealing with computational flow dynamic analyses (CFDA) in cerebral aneurysms published in the medical literature. Several forces e.g. shear forces and impact forces were calculated in order to evaluate the stress applied to the vessel wall. In order to evaluate these forces using a computational fluid analysis programme some physiological parameters like the viscosity of the blood or the elasticity of the vessel wall have to be chosen. In different publications different parameters were employed. Furthermore these computer programmes have been developed for engineering purposes and mostly not been evaluated in a biomedical setting. Aim of this study was to develop a simple glass model for direct simplified measurements of the flowdynamics in aneurysms.

Methods: A simple glass model with smooth angels was blown by an expert glass blower. A bifurcation aneurysm was chosen. The parent vessel ended in the aneurysm and the branches originated at an 90°angle. The model was designed so that the total area of the branches was approximately equal to the area of the parent tube so that neither acceleration nor deceleration would occur at the branch point. A modified Stehbens apparatus was used to perfuse the bifurcation. Essentially this consisted of a constant pressure reservoir filled from the taps, with the pressure kept constant by an overflow. This was connected by tygon tubing to the glass model and the outflow went via resistance to a stopcock and the sink. Evans blue dye was injected into the tygon proximal to the glass tube in order to study the flow profiles.

Results: The following flow profile could be observed. The axial stream flowed rapidly into the aneurysm sac with little deflection until it reached the apex. Then turbulences appeared within the aneurysm and the side branches. Some backflow appeared on the origin of the lower branch. Severe turbulences appeared in the parent trunk. These flow patterns were reproducible.

Conclusions: We present a simple glass model which offers the possibility of studying flow patterns in a simplified aneurysm. We know that this model does not reflect the clinical situation, but with further additions e.g. the use of pulsatile flow, and fluids mimicking blood viscosity evaluation of computer simulations and clinical situations seems possible.