Øyvind Evju, PhD candicate no. 100 at Simula, defended his thesis

On Friday January 13th, Øyvind Evju defended his PhD thesis "Computational hemodynamics in cerebral aneurysms: Robustness of rupture risk indicators under different model assumptions". The defense took place at 13.15 at Storstua, Simula.

The first PhD candidate defended his dissertation at Simula on March 22nd 2002, and on the 13th of January 2017 Øyvind Evju became candidate no. 100. We congratulate Øyvind on his successful defense!

Thesis abstract

About 3-5% of the population will harbor one or more aneurysms at some point. These ballon-like dilations of blood vessels may rupture, and cause a severe stroke. Luckily, ruptured aneurysms are rare, and treatment is available. Choosing which aneurysms to treat is a decision clinicians in this field face daily.

Recently, simulations of the blood flow in the brain has proven to be a promising tool in describing the risk of rupture for aneurysms. This is very attractive because of its non- invasive nature, where only external measurements of the patient are required. However, these simulations are complex, and require multiple assumptions.

In this thesis, the effects of several common assumptions are evaluated. The results of this thesis solidifies the foundations other studies in the field are built upon. Although errors caused by different assumptions may be large, their effects are diminished in large, quantitiative studies. However, for individualized treatment of aneurysms, more and better measurements are required. 

The thesis is written within the field of Biomedical Computing. The work has been conducted at Simula Research Laboratory.

Prior to the defense, at 10:15, Øyvind Evju presented his trial lecture "Modeling of processes such as inflammation".

The adjudication committee

  • Professor Juan Cebral, George Mason University, United States of America
  • Professor Trond Kvamsdal, NTNU, Norway
  • Professor Xing Cai, Department of Informatics, University of Oslo

Chair of the disputation

  • Professor Fritz Albregtsen, Department of Informatics


  • Professor Kent-Andre Mardal, Department of Mathematics, University of Oslo 
  • Senior Research Engineer Martin Sandve Alnæs, Simula Research Laboratory
  • Research Scientist Kristian Valen-Sendstad, Simula Research Laboratory
  • Professor Hans Petter Langtangen, Department of Informatics, University of Oslo 
  • Associate Professor Angelika Sorteberg, Department of Neurosurgery, University of Oslo

Read more

Announcement of the PhD defense at the University of Oslo's web pages.