Abstract
Purpose
This paper aims to evaluate a new iterative metal artifact reduction algorithm for post-interventional evaluation of brain tissue and intracranial arteries.
Methods
The data of 20 patients that underwent follow-up cranial CT and cranial CT angiography after clip** 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.
Results
The 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).
Conclusions
The new iterative metal artifact reduction algorithm enhances non-enhanced CT image quality after clip** or coiling, but in CT-angiography images, the contrast of adjacent vessels can be compromised.
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Bier, G., Bongers, M.N., Hempel, JM. et al. Follow-up CT and CT angiography after intracranial aneurysm clip** and coiling—improved image quality by iterative metal artifact reduction. Neuroradiology 59, 649–654 (2017). https://doi.org/10.1007/s00234-017-1855-6
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DOI: https://doi.org/10.1007/s00234-017-1855-6