Dual-Energy CTA Iodine Map Reconstructions Improve Visualization of Residual Cerebral Aneurysms following Endovascular Coiling

Example cases of residual aneurysms. A-D, Example case of a residual left middle cerebral artery bifurcation aneurysm after prior primary coil embolization. A, Single arterial phase anteroposterior cranial view on follow-up diagnostic cerebral angiogram demonstrates an aneurysm residual following coil compaction. B, Axial CCTA image at the level of the aneurysm neck. C, Axial IM-DECTA image at the level of the aneurysm neck. D, Axial MIP IM-DECTA image at the level of the aneurysm neck. Arrows indicate the location of the residual aneurysm. E-H, Example case of a residual left posterior inferior cerebellar artery aneurysm after prior primary coil embolization. E, Upper panel: arterial phase anteroposterior cranial view on follow-up diagnostic cerebral angiogram demonstrating small residual aneurysm inferior to the coil mass. Lower panel: early and midarterial phase lateral cranial views demonstrate the residual aneurysm inferior to the coil mass. F, Axial CCTA image at the level of the aneurysm neck. G, Axial IM-DECTA image at the level of the aneurysm neck demonstrating volume averaging between the artifactually “dark” inferior aspect of the coil mass and the small opacified residual aneurysm. H, Axial MIP IM-DECTA image at the level of the aneurysm neck effectively subtracting the coil mass to better delineate the small residual aneurysm.