Catheter splines with embedded circuit elements

A method for medical diagnosis or treatment, the method comprising:

• generating magnetic fields within a body of a patient;
• inserting a distal end of an insertion tube into the body;
• deploying a plurality of flexible splines from the distal end of the insertion tube into the body, each spline comprising a flexible, multilayer circuit board and a conductive trace that is formed in at least one layer of the circuit board and is configured to define one or more coils, which are disposed along a length of the spline and output electrical signals in response to the magnetic fields;
• and
• processing the electrical signals output by the coils in order to derive respective positions of the flexible splines in the body.

A method for producing an invasive probe, comprising:

• providing an insertion tube having a distal end, which is configured for insertion into the body;
• depositing multiple, successive layers of metal traces and dielectric material on a flexible polymer substrate to produce a flexible printed circuit board, including a conductive trace that is formed in at least one of the layers and is configured to define multiple coils;
• slicing the flexible printed circuit board into a plurality of ribbons;
• and
• deploying the ribbons as flexible splines extending from the distal end of the insertion tube.