Читать книгу Essentials of MRI Safety - Donald W. McRobbie - Страница 32
ELECTROMAGNETIC FIELDS
ОглавлениеThe extent and magnitude of the fields involved in MRI are summarized in table 1.1 and Figure 1.21.
Table 1.1 Magnetic fields in MRI.
| Field | Amplitude | Frequency / Slew rate | Pulse duration |
| Static field B0 | 0.2‐7 T | 0 Hz | Always present |
| Static fringe field spatial gradient dB/dz | 0‐25 T m–1 | 0 Hz | Always present |
| Imaging gradients Gx, Gy, Gz | 0‐80 mT m–1 | 0‐10 kHz 0‐200 T m–1 s–1 | 0‐10 ms |
| RF transmit field B1 | 0‐50 μT | 8‐300 MHz | 0‐10 ms |
Figure 1.21 Relative magnitude of magnetic fields used in MRI.
