Analysis Of Hemodynamic Of Posterior Communicating Artery Aneurysm With Oculomotor Nerve Palsy

Objective Hemodynamic factors are commonly deemed to play an important role in the pathogenesis,progression,and rupture of cerebral aneurysms.Previous hemodynamic analysis always based on comparison between post-ruptured and unruptured aneurysms.However,the changes of aneurysms morphology after ruptured led to these results questionable.To investigate the hemodynamic characteristics of posterior communicating artery aneurysm with Oculomotor Nerve Palsy by computer simulation.Methods 44 posterior communicating artery aneurysms in Yijishan hospital from January 2015 to December 2015,and they included 14 posterior communicating artery aneurysms with Oculomotor Nerve Palsy and 30 ruptured ones.The patient-special models obtained from reconstruction of three-dimensional angiography images,and we also analyzed hemodynamic characteristic of posterior communicating artery aneurysm with Oculomotor Nerve Palsy.Results The flow pattern of the posterior communicating artery aneurysms with Oculomotor Nerve Palsy was classified as type IV(6)and type III(8).The flow pattern of the ruptured posterior communicating artery aneurysms was also classified as type IV(12)and type III(18).They are all class classified as unstable flow pattern.The mean wall shear stress(WSS)of ruptured posterior communicating artery aneurysms was significantly higher than that in posterior communicating artery aneurysms with Oculomotor Nerve Palsy(7.96± 3.03 vs 13.78± 1.17,P = 0.01).The low wall shear stress area ratio(LSA%)in ruptured group were lower than those in posterior communicating artery aneurysms with Oculomotor Nerve Palsy group[3.23(2.32,3.24)% vs 9.17(8.35,12.05)%,P< 0.01].However,the normalized wall shear stress(0.53 ± 0.26 vs 0.86 ± 0.34,p=0.15),oscillatory shear index(0.04±0.338 vs 0.018±0.004,P = 0.48)were no significant differences in two groups(all P>0.05).Age(p=0.12),sex(p=0.75),hypertension(p=0.46),diabetes mellitus(P=0.82),smoking(p=0.87)and other clinical features were also no significant differences in two groupsConclusion Posterior communicating artery aneurysm with Oculomotor Nerve Palsy had a high risk of rupture.The study of this type aneurysm was of great significance to the neurosurgeon.Lower WSS and higher LSA% may contribute to the rupture of Posterior communicating artery aneurysm with Oculomotor Nerve Palsy.Age,sex,hypertension,diabetes,smoking and other clinical features do not affect the risk of posterior communicating artery aneurysm with Oculomotor Nerve PalsyComputational fluid dynamics based on imaging has a great significance in the assessment of the risk of ruptured intracranial aneurysms.Recent computational fluid dynamics studies which has indicated both high and low wall shear stress can lead to growth and rupture of intracranial aneurysm confuse clinicians and researchers.These controversial findings may derive from different parameter definitions,small simple size and intrinsic complexities of intracranial aneurysm growth and rupture.However,Meng et al.presented a uniformed presumption: either low or high wall shear stress can lead to intracranial aneurysm growth and rupture.The high wall shear stress can bring about intracranial aneurysm by mural cell–mediated and inflammatory cell–mediated destructive remodeling pathways,and the low wall shear stress result in intracranial aneurysm by inflammatory cell–mediated destructive remodeling pathways.We also review the definitions of wall shear stress parameter in various literatures and current computational fluid dynamics researches.From now on,we look forward to larger sample size,better methods of data analysis,and a more comprehensive understanding of the hemodynamic-biologic mechanisms.All these will help to more provide more accurate prediction models for intracranial aneurysm risk assessment.