The use of active noise control (ANC) to reduce acoustic noise generated during MRI scanning: some initial results.
MRI scanning generates high levels of acoustic noise that cannot only pose a safety hazard, but also impair communication between staff and patient. In this article we present active noise control (ANC) techniques that introduce antiphase noise to destructively interfere with the MRI noise and with the aim of producing a zone of quiet around the patient's ears. Using noise recorded from a 1.0 Tesla midfield MR scanner the acoustic noise generated by three standard MR imaging sequences was replayed to a real time two channel ANC system. The results obtained show a useful attenuation of low-frequency periodic acoustic noise components. Therefore, in combination with standard passive ear protection, this suggests that MR generated acoustic noise can be effectively attenuated at both low and high frequencies leading to improved patient comfort.
McJury
M
M
Department of Electrical and Electronic Engineering, University of Strathclyde, Glasgow, UK.
Stewart
R W
RW
Crawford
D
D
Toma
E
E
D000162:Acoustics / Q000295:instrumentation; D000465:Algorithms; D003142:Communication; D004430:Ear Protective Devices; D005246:Feedback; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods; D008297:Male; D009622:Noise / Q000009:adverse effects / Q000517:prevention & control*; D011369:Professional-Patient Relations; D012449:Safety; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation