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

On the role of the perianeurysmal environment regarding shape and rupture risk of cerebral berry aneurysms

Umgebungskontakte und ihre Rolle für die Formgebung und das Rupturrisiko zerebraler Aneurysmen

Meeting Abstract

  • corresponding author D. San Millán Ruíz - Neuroradiologie, Universitätsspital Genf, Schweiz
  • H. Yilmaz - Neuroradiologie, Universitätsspital Genf, Schweiz
  • A.R. Dehdashti - Neurochirurgie, Universitätsspital Genf, Schweiz
  • N. DeTribolet - Neurochirurgie, Universitätsspital Genf, Schweiz
  • D.A. Rüfenacht - Neuroradiologie, Universitätsspital Genf, Schweiz

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. DocFR.10.03

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

Published: May 8, 2006

© 2006 San Millán Ruíz 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: To evaluate whether interactions between intracranial cerebral berry aneurysms and the perianeurysmal environment (PEA) in the form of contact constraints, influence aneurysm shape and risk of rupture.

Methods: A total of 190 consecutive aneurysms, of which 124 were ruptured (group 1) and 66 were unruptured, (group 2) were studied. All aneurysms underwent high resolution angiography CT (HRCT). Aneurysm size and location, type of hemorrhage, initial Glasgow coma scale (GCS) rating, WFNS grade, Fisher grade, and presence of concomitant aneurysms was recorded. Contact constraints between aneurysms and anatomical structures of the PAE were identified for each aneurysm and further subdivided into balanced or unbalanced depending on whether contact constraints were thought to have a protective or a detrimental effect. Regular or irregular shape was recorded and correlated to contact constraints.

Results: Compared to unruptured aneurysms, ruptured aneurysms were found to be larger, more irregular, develop more contact constraints with the PAE, and showed higher rates of unbalanced contacts constraints. Ruptured aneurysms had a tendency to be found in locations of constraining PAE. Irregular shape was positively correlated with the presence of an unbalanced contact constraint, even in the absence of obvious contour deformations from an imprint of an adjacent structure.

Conclusions: Contact constraints between intracranial saccular aneurysms and the PAE were shown to influence shape and risk of aneurysm rupture. Modifications of wall shear stress by contact constraints are discussed. Analysis of contact constraints between aneurysm and the PAE could be considered as additional parameters in the assessment of the risk of aneurysm rupture.