Assessment of MRI Issues at 3 Tesla for a New Metallic Tissue Marker.
Purpose. To assess the MRI issues at 3 Tesla for a metallic tissue marker used to localize removal areas of tissue abnormalities. Materials and Methods. A newly designed, metallic tissue marker (Achieve Marker, CareFusion, Vernon Hills, IL) used to mark biopsy sites, particularly in breasts, was assessed for MRI issues which included standardized tests to determine magnetic field interactions (i.e., translational attraction and torque), MRI-related heating, and artifacts at 3 Tesla. Temperature changes were determined for the marker using a gelled-saline-filled phantom. MRI was performed at a relatively high specific absorption rate (whole body averaged SAR, 2.9-W/kg). MRI artifacts were evaluated using T1-weighted, spin echo and gradient echo pulse sequences. Results. The marker displayed minimal magnetic field interactions (2-degree deflection angle and no torque). MRI-related heating was only 0.1°C above background heating (i.e., the heating without the tissue marker present). Artifacts seen as localized signal loss were relatively small in relation to the size and shape of the marker. Conclusions. Based on the findings, the new metallic tissue marker is acceptable or "MR Conditional" (using current labeling terminology) for a patient undergoing an MRI procedure at 3 Tesla or less.
Loyola Marymount University, 1 LMU Drive, Los Angeles, CA 90045, USA.
Charlotte M
CM
Cronenweth
Keck School of Medicine, University of Southern California and Institute for Magnetic Resonance Safety, Education, and Research, 7751 Veragua Drive, Playa Del Rey, CA 90293, USA.
Frank G
FG
Shellock