Background Vessel wall MRI (VW MRI) has emerged as a potentially useful tool for differential diagnosis of various cerebrovascular diseases. As for intracranial aneurysms, it has been reported that aneurysmal wall enhancement could be an indirect marker of aneurysmal wall inflammation and unstable aneurysms.

Method VW MRI was performed in 40 patients with incidental, ruptured, symptomatic, or growing intracranial aneurysms in various locations. Imaging protocol included time-of-flight MR angiography, 3D PD VISTA, T2/PD, 3D FS iMSDE T1 VISTA pre and post-contrast scanning to evaluate the exact location, size, hemorrhage, wall thickening, and wall enhancement (focal or circumferential) of intracranial aneurysms. VW MRI findings were correlated with clinical, angiographic, and operative findings.

Results VW MRI could localize the intradural portion of paraclinoid aneurysms, differentiate junctional dilatation from true aneurysms, and diagnose dissecting aneurysms. Wall enhancement, especially circumferential wall enhancement of small aneurysms, was correlated with aneurysm growth and rupture but not with patient age and aneurysm location.

Conclusion VW MRI can be a useful tool for correct diagnosis and proper management of intracranial aneurysms. Although the clinical significance of focal wall enhancement remains to be determined, circumferential wall enhancement of small aneurysms may be a radiological marker of unstable aneurysms.

Disclosures J. Yeon: None. J. Kim: None. S. Hong: None.