Brain 3-T MR imaging using a transmit-receive head coil was safely completed in 100% (51/51) of examinations in patients with cardiac pacemakers, with no significant changes in device function.
Observational (n=44)
Is 3-T MR imaging of the brain using a transmit-receive head coil safe in patients with cardiac pacemakers?
3-T MR imaging of the brain using a transmit-receive head coil can be performed safely in patients with cardiac pacemakers when dedicated safety precautions are taken.
PURPOSE: To evaluate the safety and feasibility of 3-T magnetic resonance (MR) imaging of the brain in patients with implanted cardiac pacemakers (PMs) by using a transmit-receive head coil. MATERIALS AND METHODS: The study protocol was approved by the institutional review board. Signed informed consent was obtained from all subjects. In vitro testing at 3 T was performed with 32 PMs and 45 PM leads that were evaluated for force and torque (by using a floating platform) and radiofrequency (RF)-related heating by using a transmit-receive head coil (maximum specific absorption rate, 3.2 W/kg). Patient examinations at 3 T were performed in 44 patients with a cardiac PM and a strong clinical need; patients underwent a total of 51 MR examinations of the brain by using a transmit-receive head coil to minimize RF exposure of the PM system. An electrocardiograph and pulse oximetry were used for continuous monitoring during MR imaging. The technical and functional PM status was assessed prior to and immediately after MR imaging and at 3 months thereafter. Serum troponin I level was measured before and 12 hours after imaging to detect myocardial thermal injury. PM reprogramming was performed prior to MR imaging depending on the patient's intrinsic heart rate ( or = 60 beats per minute, sense-only mode). RESULTS: For in vitro testing, the maximum translational force was 2150 mN (mean, 374.38 mN +/- 392.75 standard deviation), and maximum torque was 17.8 x 10(-3) N x m (mean, 2.29 +/- 4.08 x 10(-3) N x m). The maximum temperature increase was 2.98 degrees C (mean, 0.16 degrees C +/- 0.45). For patient examinations, all MR examinations (51 of 51) were completed safely. There were no significant (P < .05) changes in lead impedance, pacing capture threshold level, or serum troponin I level. CONCLUSION: MR imaging of the brain at 3 T in patients with a cardiac PM can be performed safely when dedicated safety precautions (including the use of a transmit-receive head coil) are taken.
Naehle et al. (Fri,) conducted a observational in Patients with cardiac pacemakers requiring brain MRI (n=44). 3-T magnetic resonance imaging of the brain using a transmit-receive head coil was evaluated on Safety and feasibility (safe completion of MR examinations and changes in lead impedance, pacing capture threshold, or serum troponin I). Brain 3-T MR imaging using a transmit-receive head coil was safely completed in 100% (51/51) of examinations in patients with cardiac pacemakers, with no significant changes in device function.