Purpose: Wall enhancement of intracranial aneurysms in vessel wall magnetic resonance imaging (MRI) has been linked to aneurysm progression. The clinical significance of aneurysm enhancement after embolization has not yet been investigated. The goal of this study was to identify factors associated with aneurysm wall enhancement and reperfusion after embolization.
Methods: Patients who underwent treatment of intracranial aneurysms with coils or the Woven Endobridge (WEB) and follow-up MR vessel wall imaging were included. Enhancement of the treated aneurysms was separately recorded for the following locations: a) wall at the neck, b) wall at the dome, and c) in the aneurysmal cavity. Reperfusion was determined on follow-up digital subtraction angiography (DSA) and MR time of flight (TOF) angiography.
Results: In this study 48 patients with 53 aneurysms were included. Wall enhancement at the neck and the dome of the aneurysm was significantly associated with time between embolization and follow-up MRI under 6 months. Enhancement inside the aneurysmal cavity was significantly associated with a follow-up time longer than 6 months, and with stable aneurysms without reperfusion.
Conclusion: Wall enhancement is a regular feature in intracranial aneurysms after embolization and decreases over time. Enhancement inside the aneurysmal cavity is associated with a stable state and could possibly serve as an imaging marker of completed aneurysm healing.
Keywords: Coiling; Embolization; Intracranial aneurysm; Magnetic resonance imaging; Subarachnoid hemorrhage; Vessel wall imaging.