Endoscopic examining apparatus particularly useful in MRI, a probe useful in such apparatus, and a method of making such probe

Abstract

Endoscopic examining apparatus, particularly useful in MRI, includes a probe movable through the body cavity; a set of tracking coils carried by the probe; and a set of imaging coils carried by the probe. A control system controls the tracking coils to sense and indicate the location and orientation of the probe within the body cavity, and controls the imaging coils to image selected areas within the body cavity. Also described are a novel probe particularly useful in such apparatus, and a novel method of making such probes by a printed circuit technique.

1 - 34 . (canceled)  
   
   
       35 . A method of making an electrical coil assembly, comprising: 
 depositing on a planar dielectric substrate a plurality of electrically-conductive deposits in the shape of electrical coils extending parallel to each other along one orthogonal axis of the substrate and spaced from each other along the other orthogonal axis of the substrate;    forming said planar dielectric substrate into an annular shape;    and joining the opposite edges of the substrate to each other;    said plurality of electrically-conductive deposits being configured and located on said planar dielectric substrate such that when said planar dielectric substrate is formed into said annular shape and its opposite ends joined to each other, said plurality of electrically-conductive deposits defining at least two orthogonal electrical coils.    
   
   
       36 . The method according to  claim 35 , wherein at least a third orthogonal electrical coil is applied to said electrical coil assembly after the planar dielectric substrate has been formed into said annular shape and its opposite edges joined to each other.  
   
   
       37 . The method according to  claim 35 , wherein at least a third orthogonal electrical coil is included in said electrical coil assembly by depositing on said planar dielectric substrate a further electrically-conductive deposit having at least one conductive line extending along said other orthogonal axis of the substrate laterally of said plurality of electrically-conductive deposits; said further electrically-conductive deposit being configured and located so as to define said third orthogonal electrical coil when the planar dielectric substrate has been formed into said annular shape and its opposite ends joined to each other.  
   
   
       38 . The method according to  claim 37 , wherein said plurality of electrically-conductive deposits are located and configured on said planar dielectric substrate such as to define two pairs of orthogonal electrical coils.  
   
   
       39 . The method according to  claim 38 , wherein said further electrically-conductive deposit is deposited on said planar dielectric substrate on each side of the plurality of electrically-conductive deposits, such as to define a third pair of orthogonal electrical coils straddling the opposite sides of said two pairs of orthogonal electrical coils.  
   
   
       40 . The method according to  claim 35 , wherein said planar dielectric substrate is flexible and is flexed into said annular shape.  
   
   
       41 . The method according to  claim 35 , for use in making a probe for examining selected areas of a body cavity, wherein said plurality of electrically-conductive deposits are configured and located on said planar dielectric substrate such that when said substrate is formed into said annular shape with its opposite edges joined together, said plurality of electrically-conductive deposits define two sets of said orthogonal electrical coils, one set being configured for use as tracking coils for sensing the location and orientation of the probe within a body cavity, the other set configured for use as imaging coils for imaging selected areas within the body cavity.  
   
   
       42 . The method according to  claim 41 , wherein said tracking coils have a larger number of turns than said imaging coils.  
   
   
       43 . The method according to  claim 41 , wherein each of said tracking coils is coaxial with one of said imaging coils.  
   
   
       44 . The method according to  claim 41 , wherein said electrically-conductive deposits defining said tracking coils are deposited on the same side of said planar dielectric substrate as the electrically-conductive deposits defining said imaging coils.  
   
   
       45 . The method according to  claim 41 , wherein said electrically-conductive deposits defining said tracking coils are deposited on the opposite side of said planar dielectric substrate as the electrically-conductive deposits defining said imaging coils.  
   
   
       46 . The method according to  claim 41 , wherein said electrically-conductive deposits defining said tracking coils and the electrically-conductive deposits defining said imaging coils are deposited on two layers of said planar dielectric substrate.