ACOUSTIC NOISE PREDICTION AND SUBTRACTION FROM INTERCOM AUDIO SIGNAL DURING MAGNETIC RESONANCE IMAGING

摘要

In an intercom system for transmitting sound from a patient microphone disposed inside the MRI apparatus to an operator loudspeaker disposed outside the MRI apparatus, the acoustic noise generated by the MRI apparatus is predicted from gradient monitor signals representative of the drive signals applied to the gradient coils of the MRI apparatus, and is subtracted from the transmitted audio signal. The drive signals applied to the gradient coils are good noise predictors, allowing effective noise reduction. Also, the gain of the intercom system is adjusted to be higher when it is determined that the MRI apparatus is in an operational state of generating an MRI image using the gradient coils of the MRI apparatus.