Patent ID: 7962194

Claim:
An apparatus for tracking, propelling and controlling the displacement of an untethered body including magnetic field responsive material in a blood vessel of a subject, the apparatus comprising: a magnetic resonance imager (MRI) including: a bore magnet configured to produce an intense magnetic field sufficient to magnetically saturate the magnetic field responsive material of the body, said bore magnet having a hollow interior sized to receive the subject therein; a multi-dimensional magnetic field generator configured to generate a variable magnetic field gradient having a direction and magnitude; and a tracking unit configured to acquire an MRI image of the position of the body in the blood vessel and to provide position feedback information; a trajectory calculator configured to calculate a trajectory of the body in the blood vessel based at least upon the position feedback information of the body determined by the tracking unit of the MRI, a configuration of the blood vessel, and a target location to be reached by the body; and a gradient calculator configured to calculate the direction and magnitude of the gradient of the multi-dimensional magnetic field required to be applied to the magnetically-saturated body in order to propel and displace the body along the trajectory calculated by the trajectory calculator; wherein a) the generator of the MRI is configured to apply the gradient calculated by the gradient calculator to the body, and b) both the generator and the tracking unit are part of the same MRI.