Central Nervous System Siderosis Associated with Multiple Cerebral Aneurysms: Literature Review and Description of an Additional Case.

ABSTRACT

BACKGROUND: Superficial siderosis (SS) of the central nervous system is a rare disease characterized by deposition of hemosiderin along the leptomeninges due to chronic or recurrent bleeding into the subarachnoid space. The association of unruptured intracranial aneurysm (IA) and cortical SS is quite rare. METHODS: A systematic literature review to assess possible commonalities and/or differences of previous reported cases was undertaken. We report an additional case from our institution. RESULTS: A 40-year-old woman presented with a history of generalized seizures over the past year. There was no clinical history suggestive of aneurysm rupture. Magnetic resonance imaging revealed 2 aneurysms of the right middle cerebral artery (MCA) bifurcation associated with hemosiderin deposition along the right sylvian fissure and a third aneurysm of the left MCA bifurcation. Magnetic resonance imaging showed wall enhancing thickening of the larger right MCA aneurysm. The patient underwent surgical clipping of all 3 MCA aneurysms in a staged procedure. Histological examination revealed hemosiderin deposits within the aneurysm wall and surrounding gliosis. CONCLUSIONS: Our literature review found 24 reported cases of unruptured IA associated with cortical SS. The possible source for leakages could be neovessels visible in IA walls. The case reported illustrates an uncommon presentation of recurrent bleeding from an IA as a source of SS. The presence of an apparently unruptured IA surrounded by cortical SS on imaging studies is of high relevance as this should be considered a sign of aneurysm wall instability and should indicate prompt treatment.