Time-Resolved 3D-Rotational Angiography of Intracranial Vascular Malformations

• Published in: Clinical neuroradiology (Munich) 2016-09, Vol.26 (S1), p.S61
• Main Authors: Lescher, S, Klein, S, Gehrisch, S, Berkefeld, J
• Format: Article
• Language: English
• Subjects: Analysis; Angiography
• ISSN: 1869-1439

Purpose: The purpose of this pilot study was to demonstrate the applicability of time-resolved 4D reconstructions from 3D DSA rotational angiography data sets (4D DSA) to provide a more detailed display of the microvascular angioarchitecture of intracranial vascular malformations. Patients and Methods: The experimental reconstruction software was applied to the existing 3D digital subtraction angiography (3D DsA) data sets obtained at a siemens Artis Zee biplane neuroangiography equipment. We included 20 patients with clinical indications for 3D rotational angiography (RA) for preinterventional or preoperative evaluation of intracranial dural arteriovenous fistula (dAVF, n = 6) or arteriovenous malformations (AVM, n = 14). A modified DsA acquisition protocol covering an extended rotation angle of the c-arm of 260[degrees] during a scan time of 12s was used. 4D volumes were calculated with up to 30 frames/s in a transparent volume rendering (VRT)-mode and time resolved multiplanar reconstructions. 4 D-display of arterial feeders, fistulous points or the shunt zone within the AVM nidus and venous drainage were rated by consensus of two reviewers in comparison to DsA-projection images and conventional 3D DsA reconstructions without temporal resolution. Results: In all cases calculation of 4D reconstructions were technically feasible. compared to DsA-projection images 3 D- and 4 D-reconstructions helped to define a proper projection of the shunt zone. MPRs with variable slice thickness were found to be advantageous to display the angioarchitecture without overlay by adjacent vessels. Due to the additional possibility to select the proper angiographic phase and to perform video analyses, 4D VRTs and MPRs were rated significantly superior to DsA-images or 3D-reconstructions. Main drawbacks of 4D-reconstructions are time consuming post processing and potential misinterpretations of the angioarchitecture due to overlapping angiographic phases with persistent display of arteries during the venous phase. Conclusions: time resolved 3D rotational angiography with sequential or video-display of VRTs and MPRs is technically feasible and provides new insights into the micro-angioarchitecture of intracranial AV-shunts without the necessity to obtain DsA-images in multiple projections or superselective catheterizations. the new technique demands new habits of image interpretation and more standardized approaches.