A New Risk Score System To Assess Probability Of Posterior Communicating Artery Aneurysms Rupture Based On Morphological Analysis

Objective: To establish an objective risk score system to assess the status of unruptured PCo A(posterior communicating artery)aneurysms after analysing the morphological characteristics of PCo A aneurysms.Methods :75 patients with 75 PCo A aneurysms(47 ruptured,28 unruptured)were divided in two groups based on diagnosed by cerebral angiography were retrospectively collected between January 2012 and June 2017.Clinical and morphological characteristics were compared between two groups.After univariate and multivariate logistic regression analysis the independent predictors were determined for the risk score system and then established the system.Results: Morphological parameters examined for aneurysms included maximum height,height,width,height-width ratio,inflow-angle,outflow-angle,aneurysm regularity,aspect ratio and area ratio were obviously difference between two groups(P<0.05).After multivariate logistic analysis of all the parameters showed that aneurysm size(β=1.328,OR=3.773,P=0.043),inflow-angle(β=0.076,OR=1.079,P=0.003),AR(β=2.086,OR=8.055,P=0.049)were independent factors characterizing the rupture status.Acorrding to regression coefficient β,we established risk score system R=1.3*Hmax+0.1*Inflow-angle+2.1*AR.In addition,after the analysis of ROC curve,the area under the curve of the R-score value of was 0.982 and the optimal cut-off value was 19.Conclusion: Three strongest independent morphological factors for predicting repture of PCo A aneurysm were size,inflow-angle and aspect ratio.Risk score R=1.3*Hmax+0.1*Inflow-angle+2.1*AR.R>19 predict the rupture of PCo A aneurysms,the rupture possibility was increasing consensus with R-score extending.