TABLE II.
Monophasic stimulator peak parameter comparison†
| parameter | stimulator type | unit | |||
|---|---|---|---|---|---|
| Magstim 200 | BiStim | cTMS | |||
|
| |||||
| VC | capacitor voltage | 2.8 | 2.8 | 1.65 | kV |
| C | energy-storage capacitance | 185 | 370 | 716 | μF |
| WC | stored energy | 725 | 1,450 | 981 | J |
| IL | coil current | 8.7 | 12.0 | 9.5 | kA |
| B | magnetic field strength | 1.6 | 2.8 | 2.2 | T |
| tr | magnetic field rise time | 84 | 117 | 160 | μs |
| E | electric field strength | 540 | 540 | 319 | V/m |
| J | induced current density | 19 | 19 | 11 | mA/cm2 |
| ρq | induced charge density | 1.0 | 1.3 | 1.0 | μC/cm2 |
| ΔVm | neuronal membrane depolarization | 39 | 49 | 34 | mV |
†
Peak values induced in brain tissue (grey matter conductivity = 0.35 S/m) with 70 mm Magstim figure-of-eight coil. Neuronal membrane time constant τm = 150 μs.