REDUCING THE RADIO-FREQUENCY TRANSMIT FIELD IN A PREDETERMINED VOLUME DURING MAGNETIC RESONANCE IMAGING

摘要

Embodiments of the invention relate to a magnetic resonance imaging system (300) for acquiring magnetic resonance data (358) from a subject (318) that may comprise an electrically conductive object (e.g. an implant or a medical device). The magnetic resonance imaging system comprises a radio-frequency transmitter (314) for generating a radio-frequency transmit field for acquiring the magnetic resonance data using a radio-frequency antenna (310). The radio-frequency transmitter has multiple transmit channels. The radio-frequency antenna comprises multiple antenna elements (312) each adapted to connect to an antenna element. According to an embodiment of the invention, the amplitude and phase values of the RF transmit field of each of the transmit channels are selected such that the magnetic field generated by the RF antenna is minimized at the location of the electrically conductive object, thereby reducing RF heating of the object.