Long-term predictive factors of the morphology based outcome in bare platinum coiled intracranial aneurysms: Evaluation by pre- and post-contrast 3D time-of-flight MR angiography.

PURPOSE: Our aim was to identify long-term predictive factors of the morphology-based outcome (MBO) of bare platinum coiled intracranial aneurysms. MATERIALS AND METHODS: A retrospective analysis of 96 bare platinum coiled intracranial aneurysms followed up from 1997 to 2016 using pre- and post-contrast 3D time-of-flight MR angiography (MRA) was performed. Logistic regression analysis was used to identify factors associated with a positive history of surrounding coil mass enhancement (SCME) and poor MBO. Spearman's rank correlation test was used to analyze the relationship between the initial angiographic result (IAR) class, sequential change of the SCME category, and MBO grade. RESULTS: Factors independently associated with poor MBO were incomplete IAR (OR=14.94, 95%CI: 2.46, 289.21, P=0.002) and a history of SCME (OR=4.13, 95% CI: 1.05, 18.65, P=0.043). The MBO grade strongly correlated with the IAR class (correlation coefficient [r]=0.84, P<0.0001). MBO grade correlated with sequential change of the SCME category (r=0.56, P<0.0001). The sequential change of the SCME category correlated with IAR class (r=0.53, P<0.0001). CONCLUSION: Although IAR and its class were strong long-term predictive factors of MBO, a history of SCME and upgrading of sequential change of SCME category were also long-term predictive factors of the MBO of bare platinum coiled intracranial aneurysms.