MRI compatible Tissue Expanders: Advancing Safe Breast Reconstruction

Introduction

Breast cancer remains one of the most commonly diagnosed malignancies worldwide, with millions of women undergoing mastectomies each year. For many, breast reconstruction plays a vital role in restoring body image and psychological well-being. One of the most widely used techniques for reconstruction is the two-stage breast reconstruction, which involves the use of a tissue expander (TE). These expanders allow gradual stretching of skin and tissue before the final implant placement.

A recent study published in the Aesthetic Surgery Journal, titled “Benefits of Using Magnetic Resonance Imaging During Breast Tissue Expansion: Literature Review and Case Series”, by Christine Clausen-Oreamuno, Silvia Perez-Rodrigo, Filip B.J.L. Stillaert, Antonio Tejerina, Alejandro Tejerina, and Frank G. Shellock, explores the challenges associated with MRI imaging in patients with traditional TEs and highlights the advantages of newer RFID-enabled expanders. The study underscores the need for MRI-compatible tissue expanders, which allow for high-quality imaging while ensuring patient safety during the breast reconstruction process.

Traditional TEs often include magnetic injection ports, which interfere with imaging quality and are classified as “MR unsafe.” This classification restricts patients from undergoing MRI scans, which are crucial for cancer surveillance, implant evaluation, and disease monitoring. However, advancements in medical technology have introduced tissue expanders with radiofrequency identification (RFID)-enabled ports. Unlike their magnetic counterparts, these TEs are labeled “MR conditional,” allowing for safe MRI imaging with minimal artifacts.

This article reviews the findings of the study and discusses the implications of MRI-compatible tissue expanders in the context of breast reconstruction.

MRI and Traditional Tissue Expanders: A Safety Concern

Traditional TEs contain a magnetic injection port designed to facilitate saline injections for gradual breast expansion. While this feature helps surgeons locate the port for saline infusions, it poses a significant limitation when patients require MRI scans. Magnetic components generate substantial imaging artifacts, making it difficult to assess underlying breast tissue and complicating routine cancer surveillance.

A review of previous studies highlighted these risks. Many plastic surgeons consider MRI contraindicated for patients with magnetic TEs due to the distortion and signal loss these implants cause. In several cases, patients with TEs have been denied MRI scans or required unnecessary explantation procedures to facilitate imaging. This restriction delays diagnosis, particularly in patients needing urgent breast or systemic disease evaluation.

Reports have also suggested that patients undergoing MRI with traditional TEs may experience heating and discomfort, further complicating their suitability for imaging. Consequently, radiologists often recommend alternative imaging techniques, such as ultrasound or computed tomography (CT), which may not provide the same level of diagnostic accuracy.

RFID-Enabled Tissue Expanders: A Game Changer

The development of RFID-enabled TEs offers a revolutionary solution to the limitations of traditional implants. These expanders replace the magnetic injection port with an RFID-enabled port, allowing surgeons to locate the injection site without the use of metallic components. As a result, these devices are classified as “MR conditional” and can be safely used in MRI settings.

The RFID-enabled TEs have several advantages:

MRI Compatibility – Unlike magnetic TEs, RFID-enabled expanders allow for MRI imaging without significant signal distortion. Studies evaluating their performance confirm that these expanders produce minimal artifacts and allow clear visualization of breast tissue.
Non-Invasive Injection Port Localization – The RFID technology enables easy identification of the injection site using an external handheld scanner, eliminating the need for metallic components.
Reduced Risk of MRI-Related Complications – These expanders do not generate the heating effects associated with traditional TEs, making MRI scans more comfortable and safer for patients.

A study assessing the safety profile of RFID-enabled expanders concluded that they can be used safely in both 1.5T and 3T MRI scanners. This classification enables surgeons and radiologists to incorporate MRI scans into breast cancer surveillance and post-reconstruction monitoring without concern for imaging interference.

Case Studies: MRI Use in Breast Reconstruction

The review article presents a series of clinical cases that highlight the impact of MRI-compatible TEs on patient care.

Four patients with traditional TEs experienced failed MRI evaluations due to severe imaging artifacts. In these cases, the presence of the magnetic injection port obstructed imaging of the breast tissue, requiring alternative diagnostic approaches such as ultrasound or CT.
Two patients with RFID-enabled TEs underwent successful MRI scans without interference, allowing for precise cancer surveillance and improved surgical planning.

In one case, a patient with a traditional TE required MRI to assess a suspicious lesion in the contralateral breast. However, the severe artifact caused by the TE’s magnetic port made it impossible to accurately evaluate the lesion, delaying diagnosis. Conversely, another patient with an RFID-enabled TE successfully underwent MRI imaging, which clearly visualized both the expander and surrounding tissues.

These case studies emphasize the critical role of MRI-compatible TEs in ensuring timely and effective imaging for breast cancer survivors undergoing reconstruction.

Future Implications and Clinical Recommendations

The findings of the study underscore the importance of selecting MRI-compatible expanders for patients undergoing breast reconstruction. The shift from magnetic TEs to RFID-enabled alternatives will improve access to MRI diagnostics, reduce unnecessary explantation procedures, and enhance overall patient safety.

Key Recommendations:

Adopt MR-conditional TEs for patients who may require MRI during their treatment journey.
Educate plastic surgeons and radiologists on the risks associated with traditional magnetic TEs.
Encourage further research into MRI-compatible implant technologies to optimize patient outcomes.

The introduction of MRI-compatible TEs represents a major advancement in breast reconstruction, allowing for seamless integration of imaging and surgical planning. This innovation ensures that patients receive the best possible post-mastectomy care without compromising access to essential diagnostic imaging.

Key Highlights Table

Topic	Findings
Traditional TEs and MRI Risks	Magnetic ports cause severe imaging artifacts, limiting MRI use.
MRI Safety Classifications	Traditional TEs = “MR unsafe”; RFID-enabled TEs = “MR conditional”.
New RFID TE Technology	Allows safe MRI imaging without distortion.
Case Study Results	Patients with RFID-enabled TEs successfully underwent MRI.
Clinical Impact	Enhanced screening and surgical planning for breast cancer survivors.
Surgeon Recommendations	Use MRI-compatible TEs for optimal patient safety.
Future Research Needs	Further studies required to assess long-term outcomes.

References

Clausen-Oreamuno C, Perez-Rodrigo S, Stillaert FBJL, Tejerina A, Tejerina A, Shellock FG. Benefits of Using Magnetic Resonance Imaging During Breast Tissue Expansion: Literature Review and Case Series. Aesthetic Surgery Journal. 2024; 44(1):50–59. DOI: 10.1093/asj/sjad264
Bayasgalan M, Munhoz AM, Shellock FG. Breast tissue expander with radiofrequency identification port: assessment of MRI issues. American Journal of Roentgenology. 2020; 215(1):159-164. DOI: 10.2214/AJR.19.22492

This review highlights the critical role of MRI-compatible TEs in breast reconstruction. By transitioning to RFID-enabled expanders, surgeons and radiologists can ensure improved safety, diagnostic accuracy, and better patient outcomes.