Breast MRI in patients after breast conserving surgery with sentinel node procedure using a superparamagnetic tracer

Area of Science:

• Medical Imaging
• Nanotechnology
• Surgical Procedures

Background:

• Sentinel lymph node biopsy (SLNB) using superparamagnetic iron-oxide (SPIO) nanoparticles offers advantages over standard methods.
• Residual SPIO nanoparticles can cause artifacts in follow-up magnetic resonance imaging (MRI) scans.
• A protocol is presented to grade these artifacts and minimize their impact.

Purpose of the Study:

• To evaluate the impact of SPIO nanoparticle dosage on imaging artifacts after SLNB.
• To compare artifact severity between high-dose (HD) and low-dose (LD) SPIO administration.
• To determine optimal SPIO dosage for minimizing diagnostic interference.

Main Methods:

• Follow-up mammography and MRI data from 19 patients post-SLNB were analyzed.
• Two SPIO dosage groups were studied: 2-mL subareolar (HD) and 0.1-mL intratumoral (LD).
• Experienced breast imaging radiologists assessed void artifacts and their impact on diagnostic follow-up.

Main Results:

• Artifacts were observed in 9/13 patients in the HD group up to 3.6 years post-procedure.
• No SPIO-related artifacts were detected in the LD group.
• The severity of artifacts correlated with the SPIO dose administered.

Conclusions:

• A 2-mL subareolar dose of SPIO nanoparticles for SLNB can lead to residual breast artifacts, potentially hindering follow-up MRI.
• Utilizing a 0.1-mL intratumoral dose of SPIO nanoparticles effectively avoids these artifacts.
• Optimizing SPIO dosage is crucial for maintaining diagnostic accuracy in post-SLNB imaging.