Journal ArticleDOI
Turbulence in human intracranial saccular aneurysms
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It is proposed that the turbulent blood flow within an aneurysm contributes to the degeneration of the elastica, and the producti...Abstract:
✓ Preliminary experiments with glass model bifurcation aneurysms demonstrated that turbulent flow pattern occurs in the sac of an aneurysm at a low flow rate (critical Reynolds number, 400 ± 10 S.E.M.). A prediction that flow is turbulent in the sac of human intracranial saccular aneurysms was confirmed in a clinical study. Bruits, indicative of turbulence, were recorded with a phonocatheter from the sacs of 10 out of 17 intracranial aneurysms exposed at surgery where the mean arterial pressures were above 50 mm Hg. The amplitude of the bruits varied with the pressure. All of the patients in whom no bruit was found had profound Arfonad hypotension at the time of recording. Turbulence causes vibration in the wall of a vessel. This vibration produces and accelerates degenerative changes in vascular tissue by a process similar to the structural fatigue of metals by vibration. The author proposes that the turbulent blood flow within an aneurysm contributes to the degeneration of the elastica, and the producti...read more
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Journal ArticleDOI
Physical Factors In The Initiation, Growth And Rupture Of Human Intracranial Saccular Aneurysms
TL;DR: An investigation using glass models disclosed that the apex of a bifurcation is subjected to hemodynamic forces which may initiate the aneurysmal process by producing focal destruction of the internal elastic membrane.
Journal ArticleDOI
Effects of size and shape (aspect ratio) on the hemodynamics of saccular aneurysms: a possible index for surgical treatment of intracranial aneurysms.
Hiroshi Ujiie,Hiroyuki Tachibana,Osamu Hiramatsu,Andrew L. Hazel,Takeshi Matsumoto,Yasuo Ogasawara,Hiroshi Nakajima,Tomokatsu Hori,Kintomo Takakura,Fumihiko Kajiya +9 more
TL;DR: The localized, extremely low-flow condition that was observed in the dome of aneurysms with aspect ratios of more than 1.6 is a common flow characteristic in the geometry of ruptured aneuryms, so great care should be taken for patients with unruptured intracranial aneurYSms with approach to rupture.
Journal ArticleDOI
Unruptured intracranial aneurysms and arteriovenous malformations: frequency of intracranial hemorrhage and relationship of lesions
TL;DR: The data suggest that the intracranial AVM's predispose to aneurysm formation within AVM feeding systems and that the mechanism is not simply based upon the high blood flow or high arteriovenous shunt in these systems.
Journal Article
Self-expanding and balloon-expandable stents in the treatment of carotid aneurysms: an experimental study in a canine model.
TL;DR: Porous, tubular self-expanding nitinol stents may become the treatment of choice for broad-based and fusiform aneurysms of the internal carotid artery, however, blood flow dynamics of the aneurYSms must be studied carefully in order to select an appropriate mesh size for complete occlusion while preserving the parent vessel.
Journal ArticleDOI
PIV-Measured Versus CFD-Predicted Flow Dynamics in Anatomically Realistic Cerebral Aneurysm Models
Matthew D. Ford,Hristo N. Nikolov,Jaques S. Milner,Stephen P. Lownie,Edwin M. DeMont,Wojciech Kalata,Francis Loth,David W. Holdsworth,David A. Steinman +8 more
TL;DR: Overall good agreement between PIV and CFD suggests that CFD can reliably predict the details of the intra-aneurysmal flow dynamics observed in anatomically realistic in vitro models.
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