Specific absorption rate (SAR) and temperature distributions, produced inside a thorax model by a magnetic resonance imaging (MRI) apparatus equipped with a birdcage antenna operating at 64 MHz with 100 W of radiated power, have been studied both experimentally and numerically. A pacemaker equipped with a 60-cm long catheter has then been inserted inside the thorax. The presence of this implant gives rise to peak SAR averaged over 1 mm3 of about 1800 W/kg close to the catheter tip, while the average SAR is about 1 W/kg, that is the same value obtained in the absence of the pacemaker. This peak SAR gives rise to temperature increments up to 6 °C for 6 minute MRI investigations. However, lower temperature increments are expected if blood perfusion and thermoregulation are considered
SAR and temperature elevations in pacemaker holders exposed to EM fields produced by MRI apparatus / Pisa, Stefano; Calcagnini, G; Cavagnaro, Marta; Piuzzi, Emanuele; Triventi, M; Bernardi, Paolo Italo. - (2006), pp. 1754-1757. (Intervento presentato al convegno IEEE MTT-S International Microwave Symposium Digest tenutosi a San Francisco, California nel June 11–16, 2006) [10.1109/MWSYM.2006.249384].
SAR and temperature elevations in pacemaker holders exposed to EM fields produced by MRI apparatus
PISA, Stefano;CAVAGNARO, Marta;PIUZZI, Emanuele;BERNARDI, Paolo Italo
2006
Abstract
Specific absorption rate (SAR) and temperature distributions, produced inside a thorax model by a magnetic resonance imaging (MRI) apparatus equipped with a birdcage antenna operating at 64 MHz with 100 W of radiated power, have been studied both experimentally and numerically. A pacemaker equipped with a 60-cm long catheter has then been inserted inside the thorax. The presence of this implant gives rise to peak SAR averaged over 1 mm3 of about 1800 W/kg close to the catheter tip, while the average SAR is about 1 W/kg, that is the same value obtained in the absence of the pacemaker. This peak SAR gives rise to temperature increments up to 6 °C for 6 minute MRI investigations. However, lower temperature increments are expected if blood perfusion and thermoregulation are consideredI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.