Archive

Reduction of implant RF heating through modification of transmit coil electric field.

This engineering study describes modifying MRI RF transmit coil electric-field distributions to create electric field-free zones without substantially changing transmit sensitivity. Phantom experiments are reported to show reduced implant heating when a zero electric-field plane is aligned with the implant location.…

In vitro tests reveal sample radiofrequency identification readers inducing clinically significant electromagnetic interference to implantable pacemakers and implantable cardioverter-defibrillators.

This in vitro study tested electromagnetic compatibility between passive RFID readers and 15 pacemakers plus 15 ICDs across 134 kHz, 13.56 MHz, and 915 MHz bands. EMI reactions were common with low-frequency RFID and rare with high-frequency RFID, while no reactions were observed with ultra-high-frequency or…

Improvement in magnetic field immunity of externally-coupled transcutaneous energy transmission system for a totally implantable artificial heart.

This engineering study addresses interference between induction-heating cookers and an externally coupled transcutaneous energy transmission system for a totally implantable artificial heart. The authors report that magnetic flux from an IH cooker can couple into the TET transformer and affect system performance. A…

Radiofrequency dosimetry in subjects implanted with metallic straight wires: a numerical study.

This numerical FDTD study modeled RF exposure at 900 and 1800 MHz in tissue containing thin metallic straight wire implants. The model indicates that the wire can substantially increase local SAR, creating high SAR gradients. Despite this, the authors report that exposures below current safe levels resulted in…