Quantitative and Qualitative Comparison of 4D-DSA with 3D-DSA Using Computational Fluid Dynamics Simulations in Cerebral Aneurysms

Images exemplarily show measurements of the aneurysmal ostium (A and B) and the aneurysm itself (C and D) for calculation of the ostium size, maximum diameter, and aneurysmal volume.

Illustrative case 1. CFD simulations show a saccular aneurysm of the ICA. Upper row (A–D) and lower row (E–H) show reconstruction results derived from a 3D-DSA and a 4D-DSA dataset, respectively. A and E, 3D view of the aneurysm using a volume-rendering technique and demonstrating comparable aneurysmal morphology. B and F, A color-coded visualization of intra-aneurysmal flow using streamlines (red and blue indicate high- and low-velocity magnitudes). The peak velocities show a laminar distribution along the longitudinal axis. C and G, In concordance, note maximum systolic wall shear stress (red and blue indicate high and low WSS) in the corresponding area. D and H, The aneurysmal ostium, the associated flow conditions, and the corresponding areas with high-velocity magnitude (red and blue indicate high- and low-velocity magnitude). Overall, the congruence of hemodynamic characteristics between 3D- and 4D-DSA shows geometric accordance between both techniques.