American Journal of Neuroradiology 23:1795-1802, November-December 2002
© 2002 American Society of Neuroradiology
BRAIN
MR Imaging-Related Heating of Deep Brain Stimulation Electrodes: In Vitro Study
a Division of Radiology, Section of Stereotactic and Functional Neurosurgery, The Cleveland Clinic Foundation, Cleveland, OH
b Neuroradiology Section, and the Division of Surgery, Section of Stereotactic and Functional Neurosurgery, The Cleveland Clinic Foundation, Cleveland, OH
c Department of Computer and Electrical Engineering, Purdue University, West Lafayette, IN
d Medtronic, Inc., Minneapolis, MN
e Keck School of Medicine, Los Angeles, CA
Address reprint requests to Daniel A. Finelli, MD, Section of Neuroradiology/L10, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195
BACKGROUND AND PURPOSE: Recent work has shown a potential for excessive heating of deep brain stimulation electrodes during MR imaging. This in vitro study investigates the relationship between electrode heating and the specific absorption rate (SAR) of several MR images.
METHODS: In vitro testing was performed by using a 1.5-T MR imaging system and a head transmit-receive coil, with bilateral deep brain stimulation systems positioned in a gel saline-filled phantom, and temperature monitoring with a fluoroptic thermometry system. Standardized fast spin-echo sequences were performed over a range of high, medium, and low SAR values. Several additional, clinically important MR imaging techniques, including 3D magnetization prepared rapid acquisition gradient-echo imaging, echo-planar imaging, quantitative magnetization transfer imaging, and magnetization transfer-suppressed MR angiography, were also tested by using typical parameters.
RESULTS: A significant, highly linear relationship between SAR and electrode heating was found, with the temperature elevation being approximately 0.9 times the local SAR value. Minor temperature elevations, <1°C, were found with the fast spin-echo, magnetization prepared rapid acquisition gradient-echo, and echo-planar clinical imaging sequences. The high dB/dt echo-planar imaging sequence had no significant heating independent of SAR considerations. Sequences with magnetization transfer pulses produced temperature elevations in the 1.0 to 2.0°C range, which was less than theoretically predicted for the relatively high SAR values.
CONCLUSION: A potential exists for excessive MR imaging-related heating in patients with deep brain stimulation electrodes; however, the temperature increases are linearly related to SAR values. Clinical imaging sequences that are associated with tolerable temperature elevations in the 
2.0°C range at the electrode tips can be performed safely within an SAR range <2.4 W/kg local (0.9 W/kg whole body averaged).
This article has been cited by other articles:
 |
|
 |
|
  C.H. Vite, S. Magnitsky, D. Aleman, P. O'Donnell, K. Cullen, W. Ding, S. Pickup, J.H. Wolfe, and H. Poptani Apparent Diffusion Coefficient Reveals Gray and White Matter Disease, and T2 Mapping Detects White Matter Disease in the Brain in Feline Alpha-Mannosidosis AJNR Am. J. Neuroradiol., February 1, 2008; 29(2): 308 - 313. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Levin, A. O. Ortiz, and D. S. Katz Noncardiac Implantable Pacemakers and Stimulators: Current Role and Radiographic Appearance Am. J. Roentgenol., April 1, 2007; 188(4): 984 - 991. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. D. Phillips, K. B. Baker, M. J. Lowe, J. A. Tkach, S. E. Cooper, B. H. Kopell, and A. R. Rezai Parkinson Disease: Pattern of Functional MR Imaging Activation during Deep Brain Stimulation of Subthalamic Nucleus--Initial Experience. Radiology, April 1, 2006; 239(1): 209 - 216. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
F. G. Shellock and J. V. Crues MR Procedures: Biologic Effects, Safety, and Patient Care Radiology, September 1, 2004; 232(3): 635 - 652. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Roguin, M. M. Zviman, G. R. Meininger, E. R. Rodrigues, T. M. Dickfeld, D. A. Bluemke, A. Lardo, R. D. Berger, H. Calkins, and H. R. Halperin Modern Pacemaker and Implantable Cardioverter/Defibrillator Systems Can Be Magnetic Resonance Imaging Safe: In Vitro and In Vivo Assessment of Safety and Function at 1.5 T Circulation, August 3, 2004; 110(5): 475 - 482. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. T. Martin, J. A. Coman, F. G. Shellock, C. C. Pulling, R. Fair, and K. Jenkins Magnetic resonance imaging and cardiac pacemaker safety at 1.5-Tesla J. Am. Coll. Cardiol., April 7, 2004; 43(7): 1315 - 1324. [Abstract] [Full Text] [PDF]
|
|