Abstract:
:Deep brain stimulation (DBS) is used increasingly in the field of movement disorders. The implanted electrodes create not only a prior risk to patient safety during MRI, but also a unique opportunity in the collection of functional MRI data conditioned by direct neural stimulation. We evaluated MRI-related heating for bilateral neurostimulation systems used for DBS with an emphasis on assessing clinically relevant imaging parameters. Magnetic resonance imaging was performed using transmit body radiofrequency (RF) coil and receive-only head RF coil at various specific absorption rates (SARs) of RF power. In vitro testing was performed using a gel-filled phantom with temperatures recorded at the electrode tips. Each DBS electrode was positioned with a single extension loop around each pulse generator and a single loop at the "head" end of the phantom. Various pulse sequences were used for MRI including fast spin-echo, echo-planar imaging, magnetization transfer contrast and gradient-echo techniques. The MRI sequences had calculated whole-body averaged SARs and local head SARs ranging from 0.1 to 1.6 W/kg and 0.1 to 3.2 W/kg, respectively. Temperature elevations of less than 1.0 degrees C were found with the fast spin-echo, magnetization transfer contrast, gradient-echo and echo-planar clinical imaging sequences. Using the highest SAR levels, whole-body averaged, 1.6 W/kg, local exposed-body, 3.2 W/kg, and local head, 2.9 W/kg, the temperature increase was 2.1 degrees C. These results showed that temperature elevations associated with clinical sequences were within an acceptable physiologically safe range for the MR conditions used in this evaluation, especially for the use of relatively low SAR levels. Notably, these findings are highly specific to the neurostimulation systems, device positioning technique, MR system and imaging conditions used in this investigation.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Bhidayasiri R,Bronstein JM,Sinha S,Krahl SE,Ahn S,Behnke EJ,Cohen MS,Frysinger R,Shellock FGdoi
10.1016/j.mri.2005.02.007subject
Has Abstractpub_date
2005-05-01 00:00:00pages
549-55issue
4eissn
0730-725Xissn
1873-5894pii
S0730-725X(05)00142-6journal_volume
23pub_type
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pub_type: 杂志文章
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更新日期:2018-02-01 00:00:00
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doi:10.1016/j.mri.2019.01.015
更新日期:2019-05-01 00:00:00