Intracranial aneurysm wall enhancement predicts aneurysm growth and rupture: a large-scale multi-center longitudinal study

Motivation: Unruptured intracranial aneurysm (UIA) with wall enhancement identified on vessel wall MRI was considered at high risk of rupture and growth. But previous longitudinal studies were limited by small sample size (n<130). Goal(s): To evaluate whether wall enhancement can predict UIA growth or rupture in a large-scale multi-center longitudinal study. Approach: 709 UIA patients were followed by 2 years. Growth or rupture was recorded as primary outcome. Results: Size ratio, aspect ratio, irregular shape and wall enhancement index were identified as factors of UIA instability. The final model has an AUC of 0.89, which was superior to traditional risk models (AUC 0.67-0.70, p<0.001). Impact: To our best knowledge, this is the largest longitudinal study using vessel wall MRI to predict the natural risk of UIA rupture and growth. The model can potentially help select small but high-risk UIAs for early intervention.