Artifacts’ Detection for MRI Non-Metallic Needles: Comparative Analysis for Artifact Evaluation Using K-Means and Manual Quantification

Abstract

Interventional biopsy needles need to be accurately localized to the target tissue during magnetic resonance imaging (MRI) interventions. In this context, severe susceptibility artifacts affect the visibility of structures in the MR images depending on the needle’s material composition. In particular, standard needles for the spinal cord made of nickel-titanium alloys (NiTi) generate massive susceptibility artifacts during MRI. Consequently, this does not allow the precise placement of the needle to the target. The aim was to prove that using a non-metallic material for the needle can significantly reduce the appearance of artifacts. Hence, this work used a new combination of non-metallic materials based on an enforced fiber bundle as an inner core with different outer hollow sheets to fabricate seven prototypes of interventional spinal needles to optimize their visualization in MRI scans. Susceptibility artifacts for the non-metallic needles were evaluated in MRI images by an automatic quantification based on a K-means algorithm and compared with manual quantification. The width and length of the artifacts were measured for each needle. The non-metallic needles showed significantly lower artifacts in comparison to the standard needle. K-means provided the capability for detecting needle artifacts in MRI images, facilitating qualitative and quantitative assessment of MRI artifacts.