Apparatus and method for four dimensional soft tissue navigation

Abstract

A surgical instrument navigation system is provided that visually simulates a virtual volumetric scene of a body cavity of a patient from a point of view of a surgical instrument residing in the cavity of the patient. The surgical instrument navigation system includes: a surgical instrument; an imaging device which is operable to capture scan data representative of an internal region of interest within a given patient; a tracking subsystem that employs electro-magnetic sensing to capture in real-time position data indicative of the position of the surgical instrument; a data processor which is operable to render a volumetric, perspective image of the internal region of interest from a point of view of the surgical instrument; and a display which is operable to display the volumetric perspective image of the patient.

What is claimed is: 
     
         1 . A device for determining the orientation and location of an endoscope comprising a five degree of freedom tip sensor, wherein the device comprises:
 an endoscope comprising a five degree of freedom tip sensor;   a processor, which according to an algorithm, is configured to perform a method for determining the orientation and location of the tip sensor comprising the steps of:
 capturing video of the patient's anatomy with the endoscope; aligning the captured video with a visual orientation of a user directing the endoscope to the anatomical position; 
 activating a steering mechanism of the endoscope to repeatedly move the tip sensor in an arc constrained to a plane; 
 determining the orientation and location of the tip sensor in the patient as the tip sensor is being repeatedly moved; 
 defining a sixth degree of freedom of the tip sensor using the determined orientation and location of the tip sensor; and 
 correlating the determined tip sensor location and orientation with one or more patient images acquired prior to the repeated movement of the tip sensor. 
   
     
     
         2 . The device of  claim 1 , wherein the tip sensor is an angled coil sensor, the coil being disposed at a 45° angle relative to a core portion of the tip sensor. 
     
     
         3 . The device of any preceding claim wherein the method of determining the orientation and location determination comprises applying a deformation vector field. 
     
     
         4 . The device of any preceding claim wherein the method of determining the orientation and location determination comprises deriving the one or more patient images from an imaging device in conjunction with a patient tracking device disposed at an external region of the patient. 
     
     
         5 . The device of any preceding claim wherein the method of determining the orientation and location determination comprises the use of a guide wire or other navigated instrument with one to one rotation is used to continuously align a virtual display view to be consistent with the captured video. 
     
     
         6 . The device of any preceding claim wherein the method of determining the orientation and location determination comprises using the captured video to adjust a virtual fly-through view to be consistent with the visual orientation of the user. 
     
     
         7 . The device of any preceding claim wherein the method of determining the orientation and location determination further comprises holding the endoscope to prevent translational movement before activating the steering mechanism to move the tip sensor in an arc constrained to a plane. 
     
     
         8 . The device of any preceding claim wherein the method of determining the orientation and location determination comprises repeatedly moving the tip sensor approximately 1 cm to 2 cm.