Suppression of radiofrequency interference in cardiac gated MRI: a simple design

Abstract

A simple design is proposed to suppress the noise pickup in the ECG leads from RF and gradient pulses during NMR imaging. The ECG signal is passed through a low-pass filter and a common-mode-rejection amplifier to reduce erroneous signal generated by the electrical ground loops. The output is gated through a CMOS switch to blank the preamplifier from the NMR during data acquisition.