Читать книгу Essentials of MRI Safety - Donald W. McRobbie - Страница 84

Suppose an implant of length 1 cm, diameter 0.2 cm is introduced into a 3 T scanner at 45° to the z‐axis, what is the torque and twisting force if the implant has χ = 0.01?

As χ is small, treat the implant as paramagnetic. Calculate the volume and use Equation 2.15

The torque is then

and the rotational force is

This is around one third of the force due to gravity.