@misc {Simula.simula.2588,
	title = {CFD Modelling of Cerebrovascular Hemodynamics: Breaking News},
	howpublished = {9th international symposium on Biomechanics in Vascular Biology and Cardiovascular Disease, Montreal, Canada, April, 2014},
	year = {2014},
	month = {04/2014},
	keywords = {Conference},
	author = {Valen-Sendstad, Kristian and Owais Mohammad {Khan} and Piccinelli, Marina and David A. {Steinman}}
}
@inproceedings {Simula.simula.2896,
	title = {Illustration-Inspired Visualization of Blood Flow Dynamics},
	journal = {World Congress of Biomechanics Proceedings},
	year = {2014},
	publisher = {JBioMech},
	type = {Conference},
	abstract = {Image-based computational fluid dynamics (CFD) has emerged as a central tool in the evaluation of hemodynamic factors in cardiovascular disease development and treatment planning, to the point where major vendors are now seeking to deploy CFD solvers on their medical imaging platforms. Detailed hemodynamic data available from CFD reveal complicated flows that are difficult to render clearly - and thus communicate to clinical stakeholders - using conventional engineering flow visualization techniques. This is especially challenging considering the four-dimensional nature of the flow patterns (i.e., varying in space and time), as well as the clinical need for generating static reports rather than cumbersome digital animations. Taking a cue from the rich history of biomedical illustration, the goal of our multi-disciplinary collaboration between the University of Toronto and the Ontario College of Art and Design University is to develop new data-driven paradigms for visualizing blood flow, based on the principles of illustration, sequential art and caricature, and informed by the visual vocabularies and conventions of radiology and vascular surgery. Our first investigations have involved the depiction of transitional flows in cerebral aneurysms. The top row of the included figure shows selected frames from an animation of vortex cores (i.e., positive and negative Q-criterion), created using the open-source scientific visualization package, Paraview. Note how difficult it is to infer the dynamics from these static images. For the bottom row, vortex cores were outlined in black to better discriminate them from each other. Surface shading was enhanced, and colouring was used to highlight selected cores, the dynamic motion of which can be followed easily across the individual frames. The original translucent lumen surface rendering was also replaced by a simple outline drawing that nevertheless retains, and perhaps even heightens, the impression of a 3D aneurysm. Although this example was composed by a professional biomedical illustrator (JH) using graphics editing tools applied to the individual static frames, we are presently working towards automating these steps in collaboration with Toronto-based Side Effects Software, developers of the Houdini 3D Animation suite widely used in the motion picture industry.},
	keywords = {Conference},
	author = {Coppin, Peter and Harvey, John and Valen-Sendstad, Kristian and David A. {Steinman}},
	editor = {Jay D. {Humphrey}}
}
@misc {Simula.simula.2590,
	title = {Unstable Flow in the Carotid Siphon: Implications for Aneurysm Initiation and Rupture},
	howpublished = {World Congress of Biomechanics},
	year = {2014},
	keywords = {Conference},
	author = {Valen-Sendstad, Kristian and Piccinelli, Marina and David A. {Steinman}}
}
@misc {Simula.simula.1982,
	title = {Impact of CFD Solution Strategy on Predicted Aneurysm Hemodynamics: Good News and Bad News},
	howpublished = {8th International Symposium on Biomechanics in Vascular Biology and Cardiovascular Disease, Rotterdam},
	year = {2013},
	month = {April},
	keywords = {Conference},
	author = {Valen-Sendstad, Kristian and David A. {Steinman}}
}
@misc {Simula.simula.1288,
	title = {Revisiting {\textquoteright}Turbulence{\textquoteright} in Cerebral Aneurysms},
	year = {2012},
	abstract = {One of the commonly made assumptions in Computational Fluid Dynamics (CFD) is that cerebral blood flow is laminar, i.e., viscous forces are dominating and the flow is smooth. The numerical methods that are used, are chosen or tailored accordingly, i.e., to converge to such a laminar flow solution with the minimal amount of work1-2. The flow is modeled with a temporal resolution far below the clinically reported frequencies3 and thus any potential flow disturbances, if physically present, are being numerically suppressed. Since no potential disturbances are resolved, no disturbances are observed and the assumption of laminar flow is therefore a self-fulfilling prophecy. Even though recent laminar CFD studies can discriminate between ruptured and unruptured aneurysms better than, e.g. aneurysm size, the link between the proposed hemodynamic agonists and the mechanisms of rupture is unclear. However, the literature contains much evidence which supports that certain aneurysms exhibit energetic high frequency flow fluctuations. For example, high frequency flow fluctuations are known to produce sound, and clinicians have reported such sound or {\textquoteright}bruits{\textquoteright} from aneurysms during craniotomy.3 The predominant frequencies were at 460 Hz, which is consistent with the energy peaks at higher frequencies recorded acoustically on the eyes in patients with aneurysms.4 Unstable flow has also been reported in glass model studies of aneurysms.5 This evidence seems to have been ignored, or at least has not received much attention in computational modeling studies. The goal of the present study was to investigate if such high-frequency flow fluctuations in intracranial aneurysms might be a common occurrence, by using thousands of time steps in contrast to, e.g., one hundred2.},
	keywords = {Conference},
	author = {Valen-Sendstad, Kristian and Mardal, Kent-Andre and David A. {Steinman}}
}
