Magnetic Resonance Imaging (MRI) is a powerful medical diagnostic tool. Unfortunately, the loud sound produced during scanning is unpleasant, potentially harmful to patients, and may limit imaging protocol. Previously, a variety of approaches have been proposed to reduce noise exposure with limited success. This work is directed at the application of an active noise control system which generates a secondary sound signal fed into a set of headphones that could be worn by the patient. To this end, prior studies have been conducted in a sound quality chamber to aid in the development and implementation of the hardware, algorithms and procedures, which resulted in an active noise cancellation system tailored to conditions present during MRI. This system performs well during physical simulation of scanning conditions. In this study, the headphones are worn by a dummy during in situ MRI scanning. Our specific effort is to take a selected set of successful experiments under simulated conditions and repeat it during live scanning to evaluate the real time performance of the system conducted in situ. The evaluation was conducted with an echo planar imaging (EPI) scanning sequence and the procedure adjusted to maximize the performance of the system. The sound pressure levels at the patient’s ear were measured with and without active control operational, and the results were compared to evaluate the active noise cancellation system’s performance during live scans. The controller produced an overall reduction of 10.6 dBA across the full audible spectrum.

References

References
1.
Kevles
,
B. H.
, 1997,
Naked to the Bone: Medical Imaging in the Twentieth Century
,
Rutgers University Press
,
New Brunswick, NJ
.
2.
Enderle
,
J.
,
Blanchard
,
S.
, and
Bronzino
,
J.
, 2000,
Introduction to Biomedical Engineering
,
Academic Press
,
San Diego, CA.
3.
Lauterbur
,
P. C.
, 1973, “
NMR Zeugmatography
,”
Nature
242
, pp.
190
191
.
4.
Mansfield
,
P.
,
Glover
,
P. M.
, and
Beaumont
,
J.
, 1998, “
Sound Generation in Gradient Coil Structures for MRI
,”
Magn. Reson. Med.
,
39
, pp.
539
550
.
5.
Hedeen
,
R. A.
, and
Edelstein
,
W. A.
, 1997, “
Characterization and Prediction of Gradient Acoustic Noise in MR Imagers
,”
Magn. Reson. Med.
,
37
, pp.
7
10
.
6.
Price
,
D. L.
,
De
Wilde
,
J. P.
,
Papadaki
,
A. M.
,
Curran
,
J. S.
, and
Kitney
,
R. I.
, 2001, “
Investigation of Acoustic Noise on 15 MRI Scanners From 0.2 T to 3 T
,”
J. Magn. Reson. Imaging
,
13
, pp.
288
293
.
7.
More
,
S. R.
,
Lim
,
T. C.
,
Li
,
M.
,
Holland
,
C. K.
,
Boyce
,
S. E.
, and
Lee
,
J. -H,
2006, “
Acoustic Noise Characteristics of a 4 Tesla MRI Scanner
,”
J. Magn. Reson. Imaging
,
23
, pp.
388
397
.
8.
Amaro
,
E.
, Jr.
,
Williams
,
S. C. R.
,
Shergill
,
S. S.
,
Fu
,
C. H. Y.
,
MacSweeney
,
M.
,
Picchioni
,
M. M.
,
Brammer
,
M. J.
, and
McGuire
,
P. K.
, 2002, “
Acoustic Noise and Functional Magnetic Resonance Imaging: Current Strategies and Future Prospects
,”
J. Magn. Reson. Imaging
,
16
, pp.
497
510
.
9.
Cho
,
Z. H.
,
Chung
,
S. T.
,
Chung
,
J. Y.
,
Park
,
S. H.
,
Kim
,
J. S.
,
Moon
,
C. H.
, and
Hong
,
I. K.
, 1998, “
A New Silent Magnetic Resonance Imaging Using a Rotating DC Gradient
,”
Magn. Reson. Med.
,
39
, pp.
317
321
.
10.
Mansfield
,
P.
,
Chapman
,
B. L. W.
,
Bowtell
,
R.
,
Glover
,
P.
,
Coxon
,
R.
, and
Harvey
,
P. R.
, 1995, “
Active Acoustic Screening: Reduction of Noise in Gradient Coils by Lorentz Force Balancing
,”
Magn. Reson. Med.
,
33
, pp.
276
281
.
11.
Bowtell
,
R. W.
, and
Mansfield
,
P.
, 1995, “
Quiet Transverse Gradient Coils Lorentz Force Balanced Designs Using Geometrical Similitude
,”
Magn. Reson. Med.
,
34
, pp.
494
497
.
12.
Dean
,
D.
,
Ginfrida
,
C.
,
Mansell
,
S.
,
Nixon
,
T.
,
Purgill
,
D.
, and
Radziun
,
M.
, 1999,
“Cryocooler Vibration Isolation and Noise Reduction in Magnetic Resonance Imaging,”
US Patent 5,864,273.
13.
Roozen
,
N.
, and
Van Schothorst
,
G.
, 2003,
“MRI Apparatus with a Piezo Actuator in a Non-Rigid Suspension of the Gradient Coil Carrier,”
US Patent 6,549,010.
14.
Edelstein
,
W.
, 2005,
“Active Vibration Compensation for MRI Gradient Coil Support to Reduce Acoustic Noise in MRI Scanners,”
US Patent, 6,894,498.
15.
Roozen
,
N.
,
La Grange
,
M.
,
Harvey
,
P.
,
Limpens
,
P.
, and
Ham
,
C.
, 2006,
“Magnetic Resonance Imaging (MRI) System Comprising Acoustic Resonators,”
US Patent 6,998,949.
16.
Mansfield
,
P.
, 2006,
“Active Acoustic Control With Flexible Joints in Gradient Coil Design for MRI,”
US Patent 7,030,610.
17.
Pla
,
F.
,
Hedeen
,
R.
,
Dobberstein
,
R.
,
Ebben
,
T.
,
Mansell
,
S.
,
Obasih
,
K.
,
Radziun
,
M.
,
Sue
,
P.
, and
Edelstein
,
W.
, 1998,
“Low Noise MRI Scanner,”
US Patent 5,793,210.
18.
Salloway
,
A. J.
, and
Gilderdale
,
D. J.
, 1995,
“Magnetic Resonance Apparatus,”
Great Britain Patent 2,281,970.
19.
Hitoshi
,
Y.
,
Shigeru
,
A.
,
Yukio
,
Y.
, and
Yasuhiko
,
O.
, 1995,
“MRI Noise Control System,”
Japanese Patent 07246193A2.
20.
Pla
,
F.
,
Hedeen
,
R.
, and
Imam
,
I.
, 1996,
“Active Control of Noise and Vibrations in Magnetic Resonance Imaging Systems Using Vibrational Inputs,”
US Patent 5,548,653.
21.
Brungart
,
D.
, 2002,
“Delay Based Active Noise Cancellation for Magnetic Resonance Imaging,”
US Patent 6,463,316.
22.
Lee
,
J.-H.
,
Rudd
,
B.
,
Li
,
M.
, and
Lim
,
T. C.
, 2008, “
Sound Reduction Technologies for MRI Scanners
,”
Recent Pat. Eng.
,
2
, pp.
72
79
.
23.
Mcjury
,
M.
,
Stewart
,
R. W.
,
Crawford
,
D.
, and
Toma
,
E.
, 1997, “
The Use of Active Noise Control (ANC) to Reduce Acoustic Noise Generated During MRI Scanning: Some Initial Results
,”
J. Magn. Reson. Imaging
,
15
, pp.
319
322
.
24.
Chen
,
C. K.
,
Chiueh
,
T. D.
, and
Chen
,
J. H.
, 1999, “
Active Cancellation System of Acoustic Noise in MR Imaging
,”
Inst. Electr. Electron. Eng. Trans. Biomed. Eng.
,
46
, pp.
186
191
.
25.
Rudd
,
B.
,
Lim
,
T. C.
, and
Lee
,
J.-H.
, 2008, “
Evaluation of MRI Compatible Headphones for Active Noise Cancellation
,” Proceedings of the National Conference on Noise Control Engineering, Dearborn, Michigan.
26.
Rudd
,
B. W.
,
Li
,
M.
,
Lim
,
T. C.
, and
Lee
,
J.-H.
, 2009, “
Experimental Study of Active Acoustic Noise Control in a 4T MRI Scanner In-Situ
,”
Proc. Int. Soc. Magn. Reson. Med.
,
17
, p.
4781
.
27.
Simmons
,
A.
, and
Hakansson
,
K.
, 2011, “
Magnetic Resonance Safety
,”
Methods Mol. Biol.
,
711
, pp.
17
28
.
28.
Abbaszadeh
,
K.
,
Heffez
,
L. B.
, and
Mafee
,
M. F.
, 2000,
Effect of Interference of Metallic Objects on Interpretation of T1-Weighted Magnetic Resonance Imagines in the Maxillofacial Region
,”
Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod.
,
89
(
6
), pp.
759
765
.
29.
Kuo
,
S. M.
, and
Morgan
,
D. R.
, 1999, “
Active Noise Control: A Tutorial Review,” Proc
,
Inst. Electr. Electron. Eng.
,
87
(
6
), pp.
943
973
.
30.
Kuo
,
S. M.
, and
Morgan
,
D. R.
, 1996,
Active Noise Control Systems: Algorithms and DSP Implementations
,
John Wiley and Sons
,
New York.
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