Superparamagnetic Iron Oxide Sentinel Node Tracer Injection: Effects on Breast MRI Quality

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Sentinel node (SN) identification is crucial in breast-conserving surgery.
• Superparamagnetic iron oxide (SPIO) tracers are increasingly used for intraoperative SN identification.
• Ferromagnetic tracers can cause artifacts in magnetic resonance imaging (MRI).

Purpose of the Study:

• To evaluate MRI artifacts from SPIO tracers used for SN identification.
• To assess the impact of these artifacts on postoperative imaging and patient management.

Main Methods:

• Retrospective review of MRI exams in patients who received SPIO SN tracer post-breast-conserving surgery.
• Analysis of MRI reports and images for SPIO residue and impact on image quality.
• Data collected from January 2015 to May 2020.

Main Results:

• 21 MRI exams in 16 patients were analyzed.
• All exams showed evidence of SPIO residue.
• 5/21 exams were non-diagnostic, and the rest were limited due to SPIO artifacts.

Conclusions:

• Radiologists must be aware of SPIO tracer use and its effect on breast MRI quality.
• SPIO residue significantly impacts the diagnostic utility of postoperative MRIs.
• Developing alternative injection methods and adjusting MRI sequences are necessary to mitigate artifacts.