Title :
Inductively powered implantable microcoil temperature measurements: safety implications and operational guidelines
Author :
Choi, Woohyek ; Ziaie, Babak
Author_Institution :
Electr. & Comp. Eng., Minnesota Univ., Minneapolis, MN, USA
Abstract :
In this paper, we report on the temperature variations on the surface of a microcoil that is inductively powered by a strong magnetic field generated by a Class-E transmitter. It is shown that microcoil temperature increase cannot be neglected and can cause tissue damage in continuous mode operations if adequate cooling is not provided by a nearby blood vessel. The microcoil operated in the air shows a temperature increase of 4.5, 2.2, and 1°C at the distances of 5, 10 and 20mm, respectively. Submerging the coil in saline resulted in 2, 1, and 0.2 °C temperature increase at similar distances. We also measured the time to reach 1 °C increase to provide an operational guideline in order to protect heat sensitive tissues from serious damage.
Keywords :
biothermics; blood vessels; inductive power transmission; magnetic fields; micromechanical devices; prosthetics; temperature measurement; transmitters; 0.2 C; 1 C; 10 mm; 2 C; 2.2 C; 20 mm; 4.5 C; 5 mm; Class-E transmitter; adequate cooling; blood vessel; continuous mode operation; heat sensitive tissue; implantable microsystem; inductive coupling; magnetic field; microcoil; operational guidelines; safety implication; temperature measurement; tissue damage; Blood vessels; Coils; Cooling; Guidelines; Magnetic field measurement; Power generation; Safety; Temperature measurement; Tissue damage; Transmitters;
Conference_Titel :
Engineering in Medicine and Biology Society, 2003. Proceedings of the 25th Annual International Conference of the IEEE
Print_ISBN :
0-7803-7789-3
DOI :
10.1109/IEMBS.2003.1280782
