4D Flat Panel Conebeam CTA for Analysis of the Angioarchitecture of Cerebral AVMs with a Novel Software Prototype

4D-fPCBCTA reconstructions of the intranidal shunt zone to demonstrate different types of transitions between arterial and venous parts of the nidus in clinical cases: A, small AVM with several direct fistulas (small red arrows) between the feeding artery passing the nidus (large red arrow) to the sidewall of the draining vein (blue arrow). No arterial or venous branching. B, Multiple direct fistulas (small red arrows) to the sidewall of the tortuous draining vein (large blue arrow). Note the perinidal connections between the feeding arteries (red hashtag) in multiple fistulas, sidewall of Fig 2B. C, A plexiform arterial network (red asterisk) before multiple small shunts to the sidewall of the draining vein (blue arrow). D, Multiple fistulous connections between lenticulostriate arteries and corresponding branches of the thalamostriate vein in a basal ganglia AVM. E, A loose network of arterial branches with transition into corresponding venous branches connected to the compartmental draining vein (blue asterisk and arrow). F, A mixed pattern with multiple direct fistulas to the sidewall of the draining vein in the upper part of the nidus (small red arrows). A plexiform network of arterial branches with corresponding venous branches to a venous confluence (blue asterisk) connected to the draining vein (blue arrow) in the lower part of the nidus.

Angioarchitecture of the shunt zones of an AVM with a multicompartmental nidus. A, Fusion image between MR imaging and 4D-fPCTA shows a right, parietal, superficial AVM in a sulcus and adjacent parenchyma. B, 4D-volume data set presented in a virtual DSA mode with a “working projection” shows 3 main arterial feeders to the upper part of the nidus (red arrow) and to the middle (red dotted line) and lower (orange dotted line) compartments of the nidus. C, 4D-fPCBCTA reconstruction demonstrates the upper arterial feeder terminating in a plexiform arterial network before transition into the compartmental draining vein (blue arrow). D, Intranidal course of the main arterial feeder terminating in the middle compartment of the nidus (red dotted line, see also B and F). Intranidal arterial branching (red asterisk) with an arterial network and multiple small shunts in the sidewall of the draining vein (blue arrows). E, An other feeder passes the nidus (orange dotted line), giving off multiple side branches (small red arrows) connected to the arterial network of the nidus. F, 4D analysis corresponds well with 2D-DSA, with the main feeder terminating in the nidus (red dotted line). G, Superselective angiogram confirms the branching point to the arterial network (red asterisk). H, Occlusion of the compartment and the compartmental draining vein after injection of Onyx. The remaining nidus is fed by the upper feeder.