Ct system with synthetic view generation

Abstract

A CT scanner system provides projection-like images of a patient volume. After a CT scan is obtained and a three-dimensional model of the patient is created, any synthetic view can be generated by choosing any array of projection lines, e.g. between a point and a surface (a flat plane, curved plane, spherical, etc) or between two surfaces (parallel or not) and summing across the projection lines. The synthetic projections can mimic certain traditional views, such as a ceph scan, Water's view, Caldwell's projection, etc or can provide a new view that is impossible or impractical with traditional x-ray equipment, such as a perfect parallel projection, or a projection that does not pass all the way through the patient.

1 . A method for generating an image of a patient including the steps of:
 a) taking a plurality of x-rays of the patient;   b) generating a three-dimensional image of the patient based upon the plurality of x-rays; and   c) generating a projection based upon the three-dimensional image of the patient, wherein the projection includes a plurality of substantially parallel projection lines.   
     
     
         2 . The method of  claim 1  wherein said step c) further includes the step of generating a ceph scan. 
     
     
         3 . The method of  claim 2  wherein said step c) further includes the step of generating the projection based upon a plurality of substantially parallel projection lines. 
     
     
         4 . The method of  claim 2  wherein said step c) further includes the step of summing along each of the plurality of projection lines, wherein the projection lines are parallel. 
     
     
         5 . The method of  claim 2  wherein the projection lines extend laterally through a head of the patient. 
     
     
         6 . A method for generating an image of a patient including the steps of:
 a) taking a plurality of x-rays of the patient;   b) generating a three-dimensional image of the patient based upon the plurality of x-rays; and   c) selecting a point and selecting a surface, wherein at least one of the point and the surface is selected by a user; and   d) generating the projection between the point and the surface based upon the three-dimensional image of the patient.   
     
     
         7 . The method of  claim 1  further including the steps of selecting a first surface and selecting a second surface, wherein said step c) further includes the step of generating the projection between the first surface and the second surface. 
     
     
         8 . The method of  claim 7  wherein at least one of the first surface and the second surface is at least partially within the three-dimensional image of the patient. 
     
     
         9 . A method for generating an image of a patient including the steps of:
 a) taking a plurality of x-rays of the patient;   b) generating a three-dimensional image of the patient based upon the plurality of x-rays;   c) providing a user with a plurality of pre-defined projections from which to choose including a projection selected by the user;   d) generating the selected projection based upon the three-dimensional image of the patient.   
     
     
         10 . The method of  claim 1  wherein said step c) further includes the steps of:
 d) displaying a portion of the three-dimensional image of the patient;   e) defining a surface on the display of the three-dimensional image of the patient via a user input; and   f) generating a projection based upon the surface drawn in said step e).   
     
     
         11 . The method of  claim 10  further including the steps of:
 g) setting a thickness of the projection based upon a user input; and   h) generating the projection in said step f) based upon the surface and the thickness.   
     
     
         12 . The method of  claim 11  wherein said step g) is performed after said step e). 
     
     
         13 . The method of  claim 10  wherein said step e) is performed by drawing a line with a user interface. 
     
     
         14 . An imaging system comprising:
 a user interface providing an option to select from a plurality of projections; and   a computer programmed to generate the plurality of projections based upon a CT scan and to display a selected one of the plurality of projections in response to a selection by a user using the user interface.   
     
     
         15 . The system of  claim 14  wherein one of the plurality of projections is a lateral ceph scan. 
     
     
         16 . The system of  claim 15  wherein the computer is further programmed to generate the lateral ceph scan based upon a plurality of at least substantially parallel projection lines through the CT scan. 
     
     
         17 . The system of  claim 16  wherein the computer is further programmed to sum along each of the plurality of projection lines, wherein the projection lines are parallel. 
     
     
         18 . The system of  claim 17  wherein the projection lines extend laterally through a head of the patient. 
     
     
         19 . The system of  claim 14  wherein the user interface further provides the ability for a user to select a point and to select a surface, wherein the computer generates the projection between the point and the surface. 
     
     
         20 . The system of  claim 14  wherein the user interface further permits a user to select a first surface and a second surface, wherein the computer generates the projection between the first surface and the second surface.