Externally programable magnetic valve assembly and controller

A system comprising:

• an externally programmable surgically-implantable shunt valve assembly including:
• a housing, an exterior of the housing being formed of a physiologically compatible material;
• a magnetically operable motor disposed within the housing, the magnetically operable motor including a stator and a rotor configured to rotate relative to the stator responsive to a changing magnetic polarity of the stator induced by an external magnetic field, the rotor including a rotor casing and a plurality of rotor permanent magnet elements disposed in a ring within the rotor casing and arranged with alternating magnetic polarities, a number of the rotor permanent magnet elements being such that radially opposing ones of the plurality of rotor permanent magnet elements have the same magnetic polarity, rotation of the rotor relative to the stator producing a selected pressure setting of the shunt valve assembly, the rotor casing including a plurality of motor teeth disposed on an upper surface thereof, the magnetically operable motor further including first and second position indicator magnets that allow the control device to magnetically determine a position of the rotor, the first position indicator magnet being coupled to the rotor and rotates with the rotor, the second position indicator magnet rotating about the central axis of rotation on a bearing independent of rotation of the rotor, the magnetically operable motor further including a mechanical brake magnetically operable between a locked position and an unlocked position and configured, in the locked position, to prevent rotation of the rotor, the mechanical brake including a brake spring having at least one arm configured to rest between adjacent ones of the plurality of motor teeth when the mechanical brake is in the locked position;
• an inlet port positioned between the rotor casing and the exterior of the housing, the inlet port terminating at its rotor casing end in a valve seat;
• a spring;
• a valve element biased against the valve seat by the spring, the valve element and the valve seat together forming an aperture;
• and
• an outlet port positioned between the rotor casing and the exterior of the housing, the shunt valve assembly configured such that the aperture opens when a pressure of the fluid in the inlet port exceeds the selected pressure setting of the shunt valve assembly so as to vent fluid through the aperture into the outlet port;
• a non-implantable transmitter head including a magnet assembly configured to produce the external magnetic field to induce the rotation of the rotor relative to the stator;
• and
• a control device coupled to the transmitter head and configured to provide a signal to the transmitter head to control the transmitter head to produce the external magnetic field so as to set the pressure setting of the shunt valve assembly to the selected pressure setting.