Transformation of a cranial fusiform aneurysm into a pseudotumoral-like mass prior to spontaneous occlusion and regression.

This report documents the evolution of a non-ruptured cranial fusiform aneurysm that underwent both spontaneous occlusion and regression. During this process, unique images of the aneurysm as a pseudotumoral-like mass were obtained. The pseudotumoral-like mass most likely reflected inflammation and secondary neovascularization within the aneurysm, supporting the theory that spontaneous aneurysmal healing involves an inflammatory process.