Abstract WP89: Hemodynamic Differences Found in Ruptured and Unruptured Aneurysms - Quantitative Comparison of 41 Cases from a Single Location
Introduction: Brain aneurysm growth and rupture has been reported to relate to hemodynamic properties. To understand the characteristics of high rupture risk blood flow, research has studied flow differences between ruptured and unruptured aneurysms. Although it is known that flow characteristics also vary between different aneurysm locations, due to the rarity of data for ruptured cases, previous reports which showed differences between ruptured and unruptured aneurysms have relied on the inclusion of cases from multiple locations for the comparison.
Hypothesis: Our aim is to test the hypothesis that hemodynamic differences between ruptured and unruptured cases can be found in aneurysms at the same location.
Methods: To include sufficient ruptured and unruptured cases, aneurysms located at the internal carotid artery-ophthalmic artery, the most common aneurysms in our center, were analyzed. A total of 41 (12 ruptured and 29 unruptured) cases treated from January 2004 to August 2011 were included. Aneurysms were studied using patient-specific hemodynamic analysis. Flow changes in different aneurysm regions and their association with rupture were analyzed quantitatively. Statistical methods including multivariate test and paired t-tests were used to investigate the flow differences between ruptured and unruptured groups.
Results: Concentrated high blood flow pulsatility was discovered in ruptured aneurysms. In contrast, the blood flow pulsatility was found to be lower and increased gradually from the neck to dome in unruptured aneurysms. Pulsatility index at regions of neck, body, and dome averaged 1.5, 1.7, and 1.5 for ruptured cases, and 1.0, 1.2, and 1.3 for unruptured cases. Quantitative comparisons of inflow and outflow that analyzed the temporal characteristics of the flow showed that significant changes within the aneurysm sac may be a key indicator related to aneurysm rupture risk (P<0.05).
Conclusions: The different hemodynamic characteristics between ruptured and unruptured cases found in our study suggest that the high pulsatility and the relationship between inflow and outflow may be useful to characterize rupture risk for aneurysms at the same location.
- © 2012 by American Heart Association, Inc.