Navigation System For And Method Of Tracking The Position Of A Work Target

Navigation system and method for tracking movement of a patient during surgery. Image data is acquired by imaging the patient with a base layer of a skin-based patient tracking apparatus secured to the patient's skin. The skin-based patient tracking apparatus includes a plurality of optical surgical tracking elements. A computer processor arrangement is adapted to implement a navigation routine. The patient position is registered to the image data. The movement of the patient is tracked based on movement of the plurality of optical surgical tracking elements. The movement of the patient's skin is tracked by determining positions of the optical surgical tracking elements both before and after a deformation of the skin-based patient tracking apparatus. Movement of the patient's skin results in corresponding movement of the surgical tracking elements to provide a dynamic reference frame for use in continuously tracking movement of a patient's skin during surgery.