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Automatic correction of dental artifacts in PET/MRI

Profile image of Francois LauzeFrancois Lauze

2015, Journal of Medical Imaging

Abstract

A challenge when using current magnetic resonance (MR)-based attenuation correction in positron emission tomography/MR imaging (PET/MRI) is that the MRIs can have a signal void around the dental fillings that is segmented as artificial air-regions in the attenuation map. For artifacts connected to the background, we propose an extension to an existing active contour algorithm to delineate the outer contour using the nonattenuation corrected PET image and the original attenuation map. We propose a combination of two different methods for differentiating the artifacts within the body from the anatomical air-regions by first using a template of artifact regions, and second, representing the artifact regions with a combination of active shape models and knearest-neighbors. The accuracy of the combined method has been evaluated using 25 18 F-fluorodeoxyglucose PET/MR patients. Results showed that the approach was able to correct an average of 97 AE 3% of the artifact areas. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

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