Correlation of cerebral microbleeds with intracranial aneurysm rupture and hemorrhage

Abstract

Objective To evaluate the effect of cerebral microbleeds (CMBs) on intracranial aneurysm rupture and hemorrhage. Methods A total of 2023 patients with intracranial single aneurysms (944 un-ruptured aneurysms and 1029 ruptured aneurysms) were enrolled in our study. The 3D-DSA was applied to all patients to evaluate the aneurysm sizes, locations, and morphous features, and to confirm the presence of A1 dominance and variations of Circle of Willis; moreover, aspect ratio (AR), size ratio (SR) and aneurismal inclination angle were measured. The presence of CMBs identified by T2-weighted gradient-recalled-echo sequence on magnetic resonance imaging (MRI) was evaluated; the clinical data of combined with/without CMBs patients were compared. Ninety-two untreated intracranial aneurysms patients combined with CMBs were followed up to evaluate the incubation periods of CMBs-related intracranial aneurysm rupture and hemorrhage; the clinical data of patients with un-ruptured aneurysms and ruptured aneurysms were compared; the risk factors of intracranial aneurysm rupture and hemorrhage were analyzed by univariate and multivariate Logistic regression analyses. Results CMBs confirmed by MR imaging were presented in 158 patients, with 7.81% incidence rate (158/2023). Age, proportion of smokers, aneurysm inclination Angle, SR, narrow neck, irregular aneurysm shape, proportion of rupture and hemorrhage, aneurysm sites, and hypertension showed significant differences between patients without CMBs and patients with CMBs (P<0.05). In the untreated intracranial aneurysms patients combined with CMBs, 27 had intracranial aneurysm rupture and 65 did not appear intracranial aneurysm rupture; the rupture time was 3-46 months, with an average of (15.07±10.76) months. As compared with the un-ruptured group, the ruptured group had a statistically higher proportion of patients with irregular aneurysm morphology (P<0.05). Univariate analysis showed that CMBs, female, age, aneurysm size, aneurysm morphology, ICA and ACA aneurysms, AR, variations of Circle of Willis, hypertension grading II and III, diabetes mellitus with fasting blood glucose≤6.0 mmol/L, hyperlipidemia, coronary heart disease, and drinking alcohol were important factors affecting intracranial aneurysm rupture, and the differences were statistically significant (P<0.05). Multivariate Logistic regression analysis showed that CMB was an independent risk factor for intracranial aneurysm rupture and hemorrhage; as compared with patients without CMBs, patients with CMBs had a 1.75 fold increased risk of aneurysm rupture. Conclusions Patients with intracranial aneurysms with older age, smaller aneurysm inclination Angle and larger SR are more likely to be associated with CMBs. Intracranial aneurysms with CMBs patients with irregular morphology are prone to have rupture and hemorrhage. CMBs is an independent risk factor for intracranial aneurysm rupture and hemorrhage. Key words: Intracranial aneurysm; Cerebral microbleed; Risk factor; Rupture and hemorrhage