Surgical simulation model generating method, surgical simulation method, and surgical simulator

Abstract

A surgical simulation model generating method which includes a first process in which a computing unit acquires geometrical information of an organ from a medical image stored in a storage unit, including an image of the organ, and generates volume data for the organ; a second process in which, after the first process, the computing unit forms nodal points by meshing the organ represented by the generated volume data; a third process in which the computing unit generates a simulated membrane that covers the organ represented by the volume data meshed in the second process; and a fourth process in which the computing unit generates a simulated organ by drawing an imaginary line so as to extend from each nodal point formed on a surface of the organ represented by the volume data meshed in the second process in a direction that intersects the simulated membrane.

1 - 7 . (canceled) 
     
     
         8 . A surgical simulation method comprising:
 a force sensing simulation process in which a computing unit causes a force sensing device to produce reaction of a simulated organ that matches the position of a simulated surgical instrument being manipulated by a surgical simulation operator and the position where said simulated surgical instrument touches said simulated organ;   a simulated motion computing process in which said computing unit acquires, from a storage unit, surgical simulation model data for a simulated organ generated by arranging an imaginary spring so as to connect between each nodal point formed by meshing an organ represented by volume data, computes the reaction of said simulated organ due to a movement of said simulated surgical instrument and the touching of said simulated organ with said simulated surgical instrument in said force sensing simulation process, and supplies said computed reaction to said force sensing simulation process, while at the same time, computing the position achieved by the motion of said simulated organ;   an image generation process in which said computing unit generates, based on the position of said simulated organ computed in said simulated motion computing process, a simulated image of said simulated organ as seen from a simulated endoscope; and   an image display process in which said computing unit displays said image generated in said image generation process on a display unit.   
     
     
         9 . A surgical simulation method as claimed in  claim 8 , wherein in said simulated motion computing process, said computing unit varies a physical value of said simulated organ according to a deformation caused on said simulated organ by a force applied to said simulated organ, and said computing unit computes the reaction of said simulated organ based on said varied physical value. 
     
     
         10 . A surgical simulation method as claimed in  claim 9 , wherein in said simulated motion computing process, said computing unit computes the reaction, f, of said simulated organ by using the equation
     f =MÜ+C{dot over (U)}+K ( U )   
       where displacement vector U represents the positional displacement of said simulated organ, stiffness matrix K represents the physical value of said simulated organ and is generated using a spring constant of said imaginary spring, matrix M is a mass matrix, and matrix C is a viscosity resistance matrix. 
     
     
         11 - 12 . (canceled) 
     
     
         13 . A surgical simulator comprising:
 a surgical simulation model data unit which stores surgical simulation model data for a simulated organ generated by arranging an imaginary spring so as to connect between each nodal point formed by meshing an organ represented by volume data;   a force sensing device which produces the reaction of said simulated organ that matches the position of a simulated surgical instrument being manipulated by a surgical simulation operator and the position where said simulated surgical instrument touches said simulated organ;   a simulated motion computing unit which acquires said surgical simulation model data from said surgical simulation model data unit, computes the reaction of said simulated organ due to a movement of said simulated surgical instrument and the touching of said simulated organ with said simulated surgical instrument at said force sensing device, and supplies said computed reaction to said force sensing device, while at the same time, computing the position achieved by the motion of said simulated organ;   an image generating unit which generates, based on the position of said simulated organ computed by said simulated motion computing unit, a simulated image of said simulated organ as seen from a simulated endoscope; and   an image display unit which displays said image generated by said image generating unit.   
     
     
         14 . A surgical simulator as claimed in  claim 13 , wherein said simulated motion computing unit varies a physical value of said simulated organ according to a deformation caused on said simulated organ by a force applied to said simulated organ, and computes the reaction of said simulated organ based on said varied physical value. 
     
     
         15 . A surgical simulator as claimed in  claim 14 , wherein said simulated motion computing unit computes the reaction, f, of said simulated organ by using the equation
     f =MÜ+C{dot over (U)}+K ( U )   
       where displacement vector U represents the positional displacement of said simulated organ, stiffness matrix K represents the physical value of said simulated organ and is generated using a spring constant of said imaginary spring, matrix M is a mass matrix, and matrix C is a viscosity resistance matrix.