MRI compatible steerable surgical apparatus and method

A steerable surgical apparatus comprising:

• a steerable surgical tubular needle comprising first and second tendons extending through an interior of the steerable surgical tubular needle;
• a needle manipulation apparatus configured to manipulate the steerable surgical tubular needle, the needle manipulation apparatus comprising a plurality of controllable actuators configured to permit adjustment of needle rotation, needle translation, and needle bending, wherein the needle manipulation apparatus is devoid of ferrous materials, wherein the plurality of controllable actuators comprises a first nonmagnetic piezoelectric actuator configured to selectively apply tension to the first tendon for bending a tip portion of the needle in a first direction, and comprises a second nonmagnetic piezoelectric actuator configured to selectively apply tension to the second tendon for bending the tip portion in a second direction, and the needle manipulation apparatus is configured to be placed and operated within a magnetic resonance imaging machine bore;
• a plurality of fiducial markers affixed to the needle manipulation apparatus;
• a plurality of encoders configured to sense movements initiated by the plurality of actuators, wherein the plurality of encoders comprises a first linear encoder having an associated first linear encoder controller configured to detect position of the first tendon, and comprises a second linear encoder having an associated second linear encoder controller configured to detect position of the second tendon;
• and
• a control unit configured to (i) utilize positional information derived from imaging the plurality of fiducial markers to establish position and orientation of the needle manipulation apparatus within the magnetic resonance imaging machine bore, and (ii) utilize signals obtained from the plurality of encoders to determine position and orientation of the steerable surgical tubular needle, including bending of the steerable surgical needle by tension applied to the first tendon by the first nonmagnetic piezoelectric actuator and applied to the second tendon by the second nonmagnetic piezoelectric actuator, when the steerable surgical needle is inserted into a body of a patient within the magnetic resonance imaging machine bore.