Haemodynamic simulation of aneurysm coiling in an anatomically accurate computational fluid dynamics model: technical note.
BACKGROUND
Computational fluid dynamics (CFD) is a numerical technique that is used for studying haemodynamic parameters in cerebral aneurysms. As it is now possible to represent an anatomically accurate intracranial aneurysm in a computational model, we have attempted to simulate its endosaccular occlusion with coils and demonstrate the haemodynamic changes induced. This is the first attempt to use this particular porous medium-based method for coiling simulation in a CFD model, to our knowledge.


METHODS
Datasets from a rotational 3-D digital subtraction angiogram of a recently ruptured anterior communicating aneurysm were converted into a 3-D geometric model and the discretized data were processed using the computational technique developed. Coiling embolisation simulation was achieved by impediment of flow through a porous medium with characteristics following a series of embolisation coils. Haemodynamic parameters studied were: pressure distribution on the vessel wall, blood velocity and blood flow patterns.


RESULTS
Significant haemodynamic changes were detected after deployment of the first coil. Similar, but less dramatic changes occurred during subsequent stages of coiling. The blood flow patterns became less vortical in the aneurysm sac as velocity decreased to stagnation and the wall pressure at the fundus was gradually reduced. Furthermore, the haemodynamic characteristics developed at the area of the neck remnant could form the basis for assessing the likelihood of delayed coil compaction and aneurysm regrowth.


CONCLUSIONS
Appropriate computational techniques show great promise in simulating the haemodynamic behaviour of the various stages in coil embolisation and may be a potentially valuable tool in interventional planning and procedural decision-making.
Mitsos
Aristotelis P
AP
Department of Neuroradiology, John Radcliffe Hospital, University of Oxford, Level 1 - West Wing, Headley Way, Headington, Oxford OX3 9DU, United Kingdom. aristotelis.mitsos@wolfson-oxford.com
Kakalis
Nikolaos M P
NM
Ventikos
Yiannis P
YP
Byrne
James V
JV
D017542:Aneurysm, Ruptured / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy; D015901:Angiography, Digital Subtraction; D017130:Angioplasty; D019295:Computational Biology; D004621:Embolization, Therapeutic; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D021621:Imaging, Three-Dimensional; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy; D008955:Models, Cardiovascular