Abstract W P29: Comparison of Multiple and Single Intracranial Aneurysm Population in a Large Referral Center. Is the Risk Higher or the Same?

Abstract

Introduction: The knowledge of the outcome in patients with multiple intra-cranial aneurysms is crucial in the management of these patients. We compared the outcome between patients with single aneurysm and those with multiple aneurysms in a large single referral center. Hypothesis: We assessed the hypothesis that the risk of rupture and mortality is higher in patients with multiple aneurysms compared to patients with a single aneurysm. Methods: In an IRB-approved study, we evaluated 32.100 head CT angiogram examination reports, (from Dec-2001 to Aug-2010) 2.624 patients had n intracranial aneurysm. Patients were classified into a single aneurysm (SA) or a multiple aneurysms (MA)group. The rupture and mortality rate was calculated per total number of patients and aneurysm for each group. Statistical analysis was performed with Student's t-test and chi-square. Results: There was a significant differences in the occurrence of SAH (SA: 22.7% vs. MA: 11%), IVH (SA: 16.4% vs. MA: 6.9%) and IPH (SA: 7.3% vs. MA: 2.1%) when the comparison was made based on aneurysm occurrence. (p<.0001). Significant difference was observed for the rupture of the aneurysms between the two groups (SA: 25.6% vs. MA: 12.2%; p<.0001). This relationship inverts when the analysis is based on individual patients, with a slightly higher rupture rate in the MA (0.28) compared with SA (0.26).Only 2 patients died in the SA group (mortality rate: 0.09) without a significant difference between the two groups (p>0.05). Conclusion: Patients with SA have as individuals a higher incidence of rupture than patients with MA. When rupture rate per aneurysm was calculated, again the SA (0.28) had a higher rate than MA (0.12) in this population. Prospective studies in patients with multiple aneurysms should be initiated.