Positron emission tomography during transcranial magnetic stimulation does not require mu-metal shielding.
Positron emission tomography during transcranial magnetic stimulation does not require mu-metal shielding.
复制标题
经颅磁刺激期间的正电子发射断层扫描不需要高导磁合金屏蔽。
DOI：
10.1016/s1053-8119(03)00239-8
复制
发表时间：
2003
期刊：
影响因子：
5.7
通讯作者：
Fox,Peter
中科院分区：
文献类型：
--
作者：
Lee,JaeSung;Narayana,Shalini;Lancaster,Jack;Jerabek,Paul;Lee,DongSoo;Fox,Peter
Recording brain activity using positron emission tomography (PET) during the stimulation of different parts of the brain by transcranial magnetic stimulation (TMS) permits the mapping of neural connections in the living human brain. However, controversy remains regarding the need for μ-metal shielding of the PET scanner during magnetic stimulation. The aim of this study was to test the effects of magnetic fields generated by TMS on PET data acquisition. With TMS-on and -off in the PET field of view, transmission scans with a68Ge/68Ga pin source and emission scans with an uniform phantom filled with water and18F were acquired. The frequency and intensity of stimulation were set at 3–5 Hz and 70–80% of the maximum output of the stimulator, respectively. The TMS coil was placed at several locations inside the PET gantry, and the main field direction of the TMS coil was varied between parallel and perpendicular orientation to the scanner's axis. Qualitative and quantitative evaluation of the sinograms of transmission PET scans and reconstructed emission images indicated no measurable differences between TMS-on and -off and post-TMS conditions for any position or orientation. The long distance between the TMS coil and the detector block in the PET scanner, as well as the rapid reduction of the magnetic field with distance (3% of maximum field at 10 cm, in air), could explain the lack of TMS interference. The brief duration (∼250 μs) of the TMS pulses relative to the total PET acquisition time would also explain the lack of TMS effects. The lack of TMS effects on the PET scanner, as well as PET imaging without any shielding, has been reported by other laboratories.
