A theoretical model for fibroblast-control led growth of saccular cerebral aneurysms
2009 (English)In: Journal of Theoretical Biology, ISSN 0022-5193, E-ISSN 1095-8541, Vol. 257, no 1, 73-83 p.Article in journal (Refereed) Published
A new theoretical model for the growth of saccular cerebral aneurysms is proposed by extending the recent constitutive framework of Kroon and Holzapfel [2007a. A model for saccular cerebral aneurysm growth by collagen fibre remodelling. J. Theor. Biol. 247, 775-787]. The continuous turnover of collagen is taken to be the driving mechanism in aneurysmal growth. The collagen production rate depends on the magnitude of the cyclic deformation of fibroblasts, caused by the pulsating blood pressure during the cardiac cycle. The volume density of fibroblasts in the aneurysmal tissue is taken to be constant throughout the growth process. The growth model is assessed by considering the inflation of an axisymmetric membranous piece of aneurysmal tissue, with material characteristics representative of a cerebral aneurysm. The diastolic and systolic states of the aneurysm are computed, together with its load-free state. It turns out that the value of collagen pre-stretch, that determines growth speed and stability of the aneurysm, is of pivotal importance. The model is able to predict aneurysms with typical berry-like shapes observed clinically, and the predicted wall stresses correlate well with the experimentally obtained ultimate stresses of this type of tissue. The model predicts that aneurysms should fail when reaching a size of about 1.2-3.6 mm, which is smaller than what has been clinically observed. With some refinements, the model may, however, be used to predict future growth of diagnosed aneurysms.
Place, publisher, year, edition, pages
2009. Vol. 257, no 1, 73-83 p.
Aneurysm, Saccular, Cerebral, Collagen, Membrane, Artery, polarized-light microscopy, human brain arteries, 3-dimensional, collagen matrices, human intracranial aneurysms, smooth-muscle-cells, in-situ, subarachnoid hemorrhage, mechanical-properties, medical, progress, layered collagen
IdentifiersURN: urn:nbn:se:kth:diva-18225DOI: 10.1016/j.jtbi.2008.10.021ISI: 000263854900008ScopusID: 2-s2.0-59649114281OAI: oai:DiVA.org:kth-18225DiVA: diva2:336271
QC 201005252010-08-052010-08-052011-01-11Bibliographically approved