Abstract：
PURPOSE:To present preliminary, in vivo temperature measurements during MRI of a pig implanted with a deep brain stimulation (DBS) system. MATERIALS AND METHODS:DBS system (Medtronic Inc., Minneapolis, MN) was implanted in the brain of an anesthetized pig. 3.0-T MRI was performed with a T/R head coil using the low-SAR GRE EPI and IR-prepped GRE sequences (SAR: 0.42 and 0.39 W/kg, respectively), and the high-SAR 4-echo RF spin echo (SAR: 2.9 W/kg). Fluoroptic thermometry was used to directly measure RF-related heating at the DBS electrodes, and at the implantable pulse generator (IPG). For reference the measurements were repeated in the same pig at 1.5 T and, at both field strengths, in a phantom. RESULTS:At 3.0T, the maximal temperature elevations at DBS electrodes were 0.46 °C and 2.3 °C, for the low- and high-SAR sequences, respectively. No heating was observed on the implanted IPG during any of the measurements. Measurements of in vivo heating differed from those obtained in the phantom. CONCLUSION:The 3.0-T MRI using GRE EPI and IR-prepped GRE sequences resulted in local temperature elevations at DBS electrodes of no more than 0.46 °C. Although no extrapolation should be made to human exams and much further study will be needed, these preliminary data are encouraging for the future use 3.0-T MRI in patients with DBS.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Gorny KR,Presti MF,Goerss SJ,Hwang SC,Jang DP,Kim I,Min HK,Shu Y,Favazza CP,Lee KH,Bernstein MAdoi
10.1016/j.mri.2012.11.005subject
Has Abstractpub_date
2013-06-01 00:00:00pages
783-8issue
5eissn
0730-725Xissn
1873-5894pii
S0730-725X(12)00434-1journal_volume
31pub_type
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