MRI Compatibility
Non-clinical testing has demonstrated that the Crux Biomedical VCF is MR Conditional. Patients with the Crux Biomedical VCF can be scanned safely, immediately after implantation, under the following conditions:

• Static magnetic field of 1.5 Tesla (1.5T) or 3.0 Tesla (3.0T).
• Maximum spatial gradient field less than or equal to 25 T/m (2,500 G/cm).
• Maximum specific absorption rate (SAR) of 2 W/kg in normal operating mode for 15 minutes of scanning at 1.5T and 3.0T.

3.0T RF Heating
In non-clinical testing with body coil excitation, the Crux Biomedical VCF produced a maximal differential temperature rise of 4.5°C at a maximum specific absorption rate (SAR) of 3.4 W/kg for 15 minutes of scanning in a 3.0-Tesla MR system (Siemens Trio, SYNGO MR A30 4VA30A software, Munich, Germany). Scaling of the SAR and observed heating indicates that a SAR of 2 W/kg would be expected to yield a localized temperature rise of 2.6°C.

1.5T RF Heating
In non-clinical testing with body coil excitation, the Crux Biomedical VCF produced a maximal temperature rise of 3.5°C at a maximum specific absorption rate (SAR) of 1.6 W/kg for 15 minutes of scanning in a 1.5-Tesla MR system (Siemens Espree, SYNGO MR B15 software, Munich, Germany). Scaling of the SAR and observed heating indicates that a SAR of 2 W/kg would be expected to yield a localized temperature rise of 4.4°C.

Caution: The RF heating behavior does not scale with static field strength. Devices which do not exhibit detectable heating at one field strength may exhibit high values of localized heating at another field strength.

MR Artifacts
In gradient and spin echo sequences, the image artifact extends approximately 8 mm from the Crux Biomedical VCF. It may be necessary to optimize MR imaging parameters for the presence of this metallic implant.

Other
Magnetically induced displacement force and torque testing indicated that the implant posed no known risks from magnetically induced displacement or force when subjected to the MR environment described in the conditions above.

Physicians should encourage patients to register the above safe scanning conditions with MedicAlert Foundation (www.medicalert.org) or equivalent organization.