TY - JOUR T1 - Metal artifact reduction for flat panel detector intravenous CT angiography in patients with intracranial metallic implants after endovascular and surgical treatment JF - Journal of NeuroInterventional Surgery JO - J NeuroIntervent Surg SP - 824 LP - 829 DO - 10.1136/neurintsurg-2015-011787 VL - 8 IS - 8 AU - Rastislav Pjontek AU - Belgin Önenköprülü AU - Bernhard Scholz AU - Yiannis Kyriakou AU - Gerrit A Schubert AU - Omid Nikoubashman AU - Ahmed Othman AU - Martin Wiesmann AU - Marc A Brockmann Y1 - 2016/08/01 UR - http://jnis.bmj.com/content/8/8/824.abstract N2 - Background Flat panel detector CT angiography with intravenous contrast agent injection (IV CTA) allows high-resolution imaging of cerebrovascular structures. Artifacts caused by metallic implants like platinum coils or clips lead to degradation of image quality and are a significant problem.Objective To evaluate the influence of a prototype metal artifact reduction (MAR) algorithm on image quality in patients with intracranial metallic implants.Methods Flat panel detector CT after intravenous application of 80 mL contrast agent was performed with an angiography system (Artis zee; Siemens, Forchheim, Germany) using a 20 s rotation protocol (200° rotation angle, 20 s acquisition time, 496 projections). The data before and after MAR of 26 patients with a total of 34 implants (coils, clips, stents) were independently evaluated by two blinded neuroradiologists.Results MAR improved the assessability of the brain parenchyma and small vessels (diameter <1 mm) in the neighborhood of metallic implants and at a distance of 6 cm (p<0.001 each, Wilcoxon test). Furthermore, MAR significantly improved the assessability of parent vessel patency and potential aneurysm remnants (p<0.005 each, McNemar test). MAR, however, did not improve assessability of stented vessels.Conclusions When an intravenous contrast protocol is used, MAR significantly ameliorates the assessability of brain parenchyma, vessels, and treated aneurysms in patients with intracranial coils or clips. ER -