CPX™ Breast Tissue Expanders are devices that contain magnetic injection domes and are NOT MRI compatible. Do not use the CPX™ Tissue Expander in patients where an MRI may be needed. DO NOT use the CPX™ Tissue Expander in patients that have a previously implanted device that could be affected by a magnetic field. The device could be moved by the MRI causing pain or displacement, potentially resulting in a revision surgery.