Method And Apparatus For Determining Tumor Shift During Surgery Using A Stereo-Optical Three-Dimensional Surface-Mapping System

A method for determining a 3D model of a surface comprising:

• calibrating 3D reconstruction parameters for at least one reference setting of an optical system;
• calibrating image warping parameters for at least one secondary calibration settings, the image warping parameters adapted to control an image warping routine to warp images taken at that secondary calibration setting into warped images corresponding to images taken at the =reference setting;
• taking a stereo image through the optical system with the optical system at a current setting;
• determining warping parameters from the image warping parameters for at least one secondary calibration setting of the at least one secondary calibration settings, the warping parameters for warping the stereo image taken at the current setting into a warped stereo image corresponding to a stereo image taken at the reference setting;
• warping the stereo image into the warped stereo image;
• determining three-dimensional (3D) warping parameters for warping a first image of the warped stereo image into a second image of the stereo image;
• and
• using the 3D warping parameters to determine the 3D model of the surface.

A system for determining a 3D model of a surface comprising:

• an optical system having a plurality of settings, each setting providing a specific focal length and magnification, the optical system comprising an encoder for observing a current setting of the optical system;
• a memory configured to contain calibrated 3D reconstruction parameters for at least one reference setting of the optical system;
• the memory further configured with image warping parameters for at least one secondary calibration setting, the image warping parameters adapted to control an image warping routine to warp images taken at that secondary calibration setting into warped images corresponding to images taken at a reference setting of the at least one reference setting;
• a camera coupled to capture stereo images through the optical system;
• a processor configured with machine readable instructions in the memory, the machine readable instructions comprising instructions for determining warping parameters from the image warping parameters for at least one secondary calibration point, the warping parameters for warping the stereo image into a warped stereo image corresponding to a stereo image taken at the reference point;
• the memory further configured with machine readable instructions for warping the stereo image into the warped stereo image;
• the memory further configured with machine readable instructions for determining three-dimensional (3D) warping parameters for warping a first image of the warped stereo image into a second image of the stereo image;
• the memory further configured with machine readable instructions for using the 3D warping parameters for determining the 3D model of the surface.

A method for determining intraoperative location of a lesion in mammalian tissue of an organ from preoperative imaging comprising:

• determining a three dimensional location of the lesion in preoperative images;
• determining three dimensional locations of surface features of the organ in the preoperative images;
• determining a preoperative surface map of the organ;
• determining an intraoperative three dimensional surface map of the organ incorporating locations of the surface features;
• determining three dimensional displacements of the surface features between their positions in preoperative images and their positions in the intraoperative three dimensional surface map of the organ;
• constraining a computer based model of deformation of the organ with both the intraoperative three dimensional surface map and the three dimensional displacements of the surface features;
• and
• applying the computer based model of deformation to determine intraoperative locations of the lesion.