A patient experiences a magnetic spatial gradient of 200G/cm. What dB/dt are they experiencing?

To calculate the dB/dt when a magnetic spatial gradient of 200 G/cm is experienced, we first convert the gradient into units that are consistent with the formula used in the context of magnetic resonance imaging (MRI).

The spatial gradient (G) in Gauss per centimeter (G/cm) can be converted to Tesla per meter (T/m) by recognizing that 1 G = 0.0001 T. Therefore, a gradient of 200 G/cm translates to 200 G/cm × 0.0001 T/G = 0.02 T/cm. Since 1 cm = 0.01 m, we can express this as 0.02 T/cm = 2 T/m.

The rate of change of magnetic field intensity (dB/dt) can be determined from the relationship between the spatial gradient and dB/dt. In MRI contexts, it is common to state that dB/dt = G × (d(distance)/d(time)). When this calculation is applied with the gradient of 2 T/m, we would see that the dB/dt value can be represented in various ways depending on the specific context and units used.

However, when determining safety implications and limits set by organizations such as