ANALYSIS OF ACOUSTIC NOISE IN MRI

Acoustic or sound noise due to gradient pulsing has been one of the pr oblems in magnetic resonance imaging (MRI), both in patient scanning a s well as in many areas of psychiatric and neuroscience research such as functional MRI. Our recent observations in functional MRI for the v isual and motor cortex show very different results with sound noise in comparison with the results obtained without sound noise, Although a number of ideas have been suggested in the literature about the possib le elimination or reduction of sound noise, progress has been slow due to the basic role of gradient pulsing in MR imaging, Before we tackle the sound-noise-reduction problem, we believe that a systematic study of sound or acoustic noise behavior will provide important informatio n for future endeavors in this area of research in MRI systems, in bot h commercial and research systems, Therefore, we report on some typica l behavior of sound noise observed from MRI scanners and the analyses of their characteristics. Data are obtained both from a commercial MRI scanner (GE Signa 1.5-T EPI system) as well as a research-type MRI sc anner (KAIS 2.0-T) developed at a university laboratory setting, (C) 1 997 Elsevier Science Inc.