Optimizing computed tomography to reduce artifacts from titanium aneurysm clips: an in vitro study

Abstract

Object At many institutions digital subtraction angiography remains the standard imaging procedure for the postoperative evaluation of patients following placement of a cerebral aneurysm clip largely because of the artifacts produced by the clip on computed tomography (CT). The authors evaluated the effect of various imaging parameters on the quality of 3D reconstructions from CT scans while imaging a phantom to optimize the CT angiograms. Methods Using multidetector CT scanners with submillimeter detector collimation (0.625 mm), the authors scanned a silicone phantom with attached commercial aneurysm clips. Slice thickness, reconstruction overlap, kilovolt level, milliampere level, and pitch were varied. Neuroradiologists, who were blinded to the scanning parameters, rated the reconstructions for image quality and artifact reduction. Results Images of the titanium clip using 140 kV and 380 mA with 0.625-mm overlapping reconstructed slices provided excellent 3D visualization of both the clip and the aneurysm model, even when using two adjacent clips. Conclusions Overlapping reconstructions combined with thin-section acquisition can provide detailed images of titanium clips and surrounding tissues without the use of low-pitch values.