Interventional Treatment Of Peripheral Intracranial Aneurysms:Short-term Results And Predictors Of Unfavorable Outcomes

BACKGROUNDPeripheral intracranial aneurysms(Peripheral Intracranial Aneurysms)grow away from the cerebral artery and vertebral basilar artery system of large branches.Incidence is about 7-9%in the anterior cerebral artery,about 2-7%in the middle cerebral artery and about 5%in the posterior cerebral artery.Some scholars reported that peripheral intracranial aneurysms often sandwich,spindle and large aneurysms.So far,the causes and natural history of peripheral intracranial aneurysms have not yet been fully elucidated,and some scholars believe that the aneurysms that occur around the arteries seem to be the result of arterial dissection.Animal models confirm hemodynamic factors and hypertension are potential factors leading to aneurysm formation.Treatment of peripheral intracranial aneurysms is still controversial.Some cases are treated by open surgery,such as direct clipping,encapsulation,with or without vascular remodeling under isolated aneurysms.However,surgical treatment methods sometimes lead to the risk of neurological deficits,especially posterior circulation aneurysms,because the lesion is closely related to the brain stem and cranial nerves.Drake reported occlusion or isolation of the posterior segment of the posterior cerebral artery(17.4%).With the continuous development of interventional techniques,intravascular interventional therapy has become another treatment to treat such lesions,and has achieved better clinical results,including selective coil embolization,tumor artery occlusion and stent support Spring ring.However,intravascular interventional treatment of such lesions after the impact of prognostic factors,there are few reports.OBJECTIVE:Peripheral intracranial aneurysms are rare lesions;the management of these lesions has been a challenge.Our present study was aimed to retrospectively evaluate the efficacy of endovascular treatment for peripheral intracranial aneurysms and explored the predictors of unfavorable outcome.Methods:The study retrospectively reviewed 63 consecutive patients with peripheral intracranial aneurysms that underwent endovascular treatment from January 2004 to January 2014.42 patients underwent selective coiling,17 patients underwent parent artery occlusion,while 4 patients underwent stent-assisted coiling.Follow-up outcomes were evaluated using modified Rankin Scale.The clinical outcomes of patients were categorized as favorable(mRS0-1)or unfavorable(mRS2-6).Results:Favorable outcomes(mRS 0-1)were obtained in 52 of 63 patients.Complete occlusion was achieved in 50 patients;partial occlusion was evident in 13 patients.Univariate analysis showed that dissecting aneurysm and partial obliteration were the risk factors for aneurysm recurrence.Coexisting hydrocephalus was the independent predictor of unfavorable outcomes in the logistic regression analysis(P=0.024).Conclusion:Our study showed that endovascular approach to treat peripheral intracranial aneurysms was safe and effective.Coexisting hydrocephalus was the independent predictor of unfavorable outcomes in the logistic regression analysis.