Magnetic resonance safety testing of a newly-developed fiber-optic cardiac pacing lead

✍ Scribed by Wilson Greatbatch; Victor Miller; Frank G. Shellock

• Book ID: 102376269
• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 487 KB
• Volume: 16
• Category: Article
• ISSN: 1053-1807
• DOI: 10.1002/jmri.10129

✦ Synopsis

Purpose:

To assess magnetic resonance (mr) safety for a newly developed, fiber-optic cardiac pacing lead.

Materials and methods:

Mr safety was assessed for the fiber-optic cardiac pacing lead by evaluating magnetic field interactions and heating. translational attraction and torque were evaluated using a 1.5-tesla mr system and previously described, standardized techniques. mr imaging-related heating was assessed using a 1.5-tesla mr system and a transmit/receive, body radiofrequency (rf) coil with the fiber-optic lead positioned to simulate an in vivo condition in a saline-filled phantom. the phantom had dimensions similar to a human subject's torso and head. a fluoroptic thermometry system was used to record temperatures on and near the electrodes of the fiber-optic pacing lead at five-second intervals immediately before and during 20 minutes of mr imaging performed at a whole-body-averaged specific absorption rate (sar) of 1.5 w/kg. temperatures were also recorded from a reference site during this experiment.

Results:

Magnetic field interactions for the fiber-optic lead were minimal (deflection angle, 23 degrees; torque, +2). the highest temperature change recorded for the fiber-optic cardiac pacing lead and reference site was +0.8 degrees c.

Conclusion:

The minor magnetic field interactions and relative lack of heating for the fiber-optic pacing lead indicate that it should be safe for patients with this device to undergo mr imaging procedures using mr systems operating at 1.5-t or less and at a whole-body-averaged sars up to 1.5 w/kg.