• Georg Bier, Malte Niklas Bongers, Johann-Martin Hempel, Anja Örgel, Till-Karsten Hauser, Ulrike Ernemann, and Florian Hennersdorf.
• Department of Diagnostic and Interventional Neuroradiology, Eberhard Karls University Tuebingen, 72076, Tuebingen, Germany. georg.bier@med.uni-tuebingen.de.
• Neuroradiology. 2017 Jul 1; 59 (7): 649-654.

PurposeThis paper aims to evaluate a new iterative metal artifact reduction algorithm for post-interventional evaluation of brain tissue and intracranial arteries.MethodsThe data of 20 patients that underwent follow-up cranial CT and cranial CT angiography after clipping or coiling of an intracranial aneurysm was retrospectively analyzed. After the images were processed using a novel iterative metal artifact reduction algorithm, images with and without metal artifact reduction were qualitatively evaluated by two readers, using a five-point Likert scale. Moreover, artifact strength was quantitatively assessed in terms of CT attenuation and standard deviation alterations.ResultsThe qualitative analysis yielded a significant increase in image quality (p = 0.0057) in iteratively processed images with substantial inter-observer agreement (ĸ = 0.72), while the CTA image quality did not differ (p = 0.864) and even showed vessel contrast reduction in six cases (30%). The mean relative attenuation difference was 27% without metal artifact reduction vs. 11% for iterative metal artifact reduction images (p = 0.0003).ConclusionsThe new iterative metal artifact reduction algorithm enhances non-enhanced CT image quality after clipping or coiling, but in CT-angiography images, the contrast of adjacent vessels can be compromised.

29 keywords...

hide…