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PT  - JOURNAL ARTICLE
AU  - Lang, S.
AU  - Hoelter, P.
AU  - Birkhold, A.I.
AU  - Schmidt, M.
AU  - Endres, J.
AU  - Strother, C.
AU  - Doerfler, A.
AU  - Luecking, H.
TI  - Quantitative and Qualitative Comparison of 4D-DSA with 3D-DSA Using Computational Fluid Dynamics Simulations in Cerebral Aneurysms
AID  - 10.3174/ajnr.A6172
DP  - 2019 Sep 01
TA  - American Journal of Neuroradiology
PG  - 1505--1510
VI  - 40
IP  - 9
4099  - http://www.ajnr.org/content/40/9/1505.short
4100  - http://www.ajnr.org/content/40/9/1505.full
SO  - Am. J. Neuroradiol.2019 Sep 01; 40
AB  - BACKGROUND AND PURPOSE: 4D-DSA allows time-resolved 3D imaging of the cerebral vasculature. The aim of our study was to evaluate this method in comparison with the current criterion standard 3D-DSA by qualitative and quantitative means using computational fluid dynamics.MATERIALS AND METHODS: 3D- and 4D-DSA datasets were acquired in patients with cerebral aneurysms. Computational fluid dynamics analysis was performed for all datasets. Using computational fluid dynamics, we compared 4D-DSA with 3D-DSA in terms of both aneurysmal geometry (quantitative: maximum diameter, ostium size [OZ1/2], volume) and hemodynamic parameters (qualitative: flow stability, flow complexity, inflow concentration; quantitative: average/maximum wall shear stress, impingement zone, low-stress zone, intra-aneurysmal pressure, and flow velocity). Qualitative parameters were descriptively analyzed. Correlation coefficients (r, P value) were calculated for quantitative parameters.RESULTS: 3D- and 4D-DSA datasets of 10 cerebral aneurysms in 10 patients were postprocessed. Evaluation of aneurysmal geometry with 4D-DSA (rmaximum diameter = 0.98, Pmaximum diameter &amp;lt;.001; rOZ1/OZ2 = 0.98/0.86, POZ1/OZ2 &amp;lt; .001/.002; rvolume = 0.98, Pvolume &amp;lt;.001) correlated highly with 3D-DSA. Evaluation of qualitative hemodynamic parameters (flow stability, flow complexity, inflow concentration) did show complete accordance, and evaluation of quantitative hemodynamic parameters (raverage/maximum wall shear stress diastole = 0.92/0.88, Paverage/maximum wall shear stress diastole &amp;lt; .001/.001; raverage/maximum wall shear stress systole = 0.94/0.93, Paverage/maximum wall shear stress systole &amp;lt; .001/.001; rimpingement zone = 0.96, Pimpingement zone &amp;lt; .001; rlow-stress zone = 1.00, Plow-stress zone = .01; rpressure diastole = 0.84, Ppressure diastole = .002; rpressure systole = 0.9, Ppressure systole &amp;lt; .001; rflow velocity diastole = 0.95, Pflow velocity diastole &amp;lt; .001; rflow velocity systole = 0.93, Pflow velocity systole &amp;lt; .001) did show nearly complete accordance between 4D- and 3D-DSA.CONCLUSIONS: Despite a different injection protocol, 4D-DSA is a reliable basis for computational fluid dynamics analysis of the intracranial vasculature and provides equivalent visualization of aneurysm geometry compared with 3D-DSA.AWSSaverage wall shear stressCFDcomputational fluid dynamicsdmaxmaximum diameterIZimpingement zoneLSZlow-stress zoneMWSSmaximum wall shear stressOZostium sizercorrelation coefficientVflow velocityWSSwall shear stress