Morphological and Hemodynamic Discriminators for Rupture Status in Posterior Communicating Artery Aneurysms

Abstract

Background and PurposeThe conflicting findings of previous morphological and hemodynamic studies on intracranial aneurysm rupture may be caused by the relatively small sample sizes and the variation in location of the patient-specific aneurysm models. We aimed to determine the discriminators for aneurysm rupture status by focusing on only posterior communicating artery (PCoA) aneurysms.Materials and MethodsIn 129 PCoA aneurysms (85 ruptured, 44 unruptured), clinical, morphological and hemodynamic characteristics were compared between the ruptured and unruptured cases. Multivariate logistic regression analysis was performed to determine the discriminators for rupture status of PCoA aneurysms.ResultsWhile univariate analyses showed that the size of aneurysm dome, aspect ratio (AR), size ratio (SR), dome-to-neck ratio (DN), inflow angle (IA), normalized wall shear stress (NWSS) and percentage of low wall shear stress area (LSA) were significantly associated with PCoA aneurysm rupture status. With multivariate analyses, significance was only retained for higher IA (OR = 1.539, p < 0.001) and LSA (OR = 1.393, p = 0.041).ConclusionsHemodynamics and morphology were related to rupture status of intracranial aneurysms. Higher IA and LSA were identified as discriminators for rupture status of PCoA aneurysms.

Morphological characteristics associated with the rupture risk of mirror posterior communicating artery aneurysms

“…This case control method cannot avoid location related bias. One previous study showed that SR was associated with rupture of small (<7 mm) PComAAs3, whereas SR exhibited no relationship between rupture of PComAAs4 and rupture of mirror PComAAs 12. Only one study has reported that SR is a risk factor associated with rupture of mirror PComAAs,13 which is in keeping with the results of the current study.…”

Angioarchitectures and Hemodynamic Characteristics of Posterior Communicating Artery Aneurysms and Their Association with Rupture Status

“…Therefore, our results are in agreement with previous studies that pointed to “high WSS” mechanisms as responsible for aneurysm rupture 25 as well as with studies that proposed “low WSS” mechanisms 10, 26, 27 . This finding suggests that previous results may not be conflicting or contradictory but rather that the different metrics used in different studies characterize different aspects of the adverse flow environment.…”

“…A previous study showed that PCOM aneurysms, along with ACOM and basilar tip aneurysms, occur more frequently in patients with an anatomical variant or incomplete circle of Willis 9 . A recent study found that inflow angle and the aneurysm area under low wall shear stress were independently associated with rupture 10 . These studies support the idea that hemodynamics is largely influenced by the local geometry of the vessels and aneurysm configurations, and that it may play an important role in the development and evolution of intracranial aneurysms at this location.…”

Development of a statistical model for discrimination of rupture status in posterior communicating artery aneurysms

“…Holding all other variables fixed, a higher probability of being ruptured was associated with larger bulge location and more elongated shape (less spherical), in agreement with previous studies [11, 19]. In our sample, a higher rupture risk was also associated with smaller aneurysm height and width, in contrast to previous studies suggesting increased rupture risk with increasing PCOM aneurysm size [12, 17].…”