Dartmouth College

Songbai Ji

Keith Douglas Paulsen

David W Roberts

Xiaoyao Fan

Alexander Hartov

Alex Hartov

Sohail K Mirza

This invention provides a hand-held stereovision (HHS) system that is an efficient, accurate, and radiation-free imaging device to acquire intraoperative profiles of the exposed spine in prone position. The reconstructed intraoperative stereovision surfaces (iSV) are registered with preoperative CT (pCT; supine position) in a nonrigid fashion to generate updated CT images (uCT) and correct for vertebral posture and alignment changes. Updated CT images are uploaded to a commercial navigation system for surgical navigation.

Hand-held stereovision system for image updating in surgery

A surgical guidance system has two cameras to provide stereo image stream of a surgical field; and a stereo viewer. The system has a 3D surface extraction module that generates a first 3D model of the surgical field from the stereo image streams; a registration module for co-registering annotating data with the first 3D model; and a stereo image enhancer for graphically overlaying at least part of the annotating data onto the stereo image stream to form an enhanced stereo image stream for display, where the enhanced stereo stream enhances a surgeon's perception of the surgical field. The registration module has an alignment refiner to adjust registration of the annotating data with the 3D model based upon matching of features within the 3D model and features within the annotating data; and in an embodiment, a deformation modeler to deform the annotating data based upon a determined tissue deformation.

Surgical navigation with stereovision and associated methods

An apparatus and method for measuring mechanical properties of tissue has a stereo optical surgical microscope with at least one objective lens and at least two digital cameras such that paired images obtained from the digital cameras form stereo pairs, and a digital image processing system adapted to determine surface topography of tissue from the stereo pairs of images and a resulting surface displacement map as a result from indentation. The apparatus has an one indenter; and mechanical modeling routines stored in memory of the image processing system, the mechanical modeling routines capable of constructing computer models of mechanical properties of tissue, and fitting parameters of the computer model to observed surface displacement maps generated by coregistering surface topography of tissue with and without the indenter positioned on the tissue. In an embodiment, fitted parameters of the computer model are displayed and used to adjust a surgical plan. An apparatus and method for measuring mechanical properties of tissue has a stereo optical surgical microscope with at least one objective lens and at least two digital cameras such that paired images obtained from the digital cameras form stereo pairs, and a digital image processing system adapted to determine surface topography of tissue from the stereo pairs of images and a resulting surface displacement map as a result from indentation. The apparatus has an one indenter; and mechanical modeling routines stored in memory of the image processing system, the mechanical modeling routines capable of constructing computer models of mechanical properties of tissue, and fitting parameters of the computer model to observed surface displacement maps generated by coregistering surface topography of tissue with and without the indenter positioned on the tissue. In an embodiment, fitted parameters of the computer model are displayed and used to adjust a surgical plan.

Apparatus for measuring in-vivo mechanical properties of biological tissues

A system for, and method of, extracting a surface profile from a stereo pair of images obtained at an arbitrary setting S of an optical system, includes determining surface profile reconstruction parameters for images obtained with the optical system at a reference setting So of the optical system; determining warping parameters for a digital image processor for warping images obtained with the optical system at the arbitrary setting S into images corresponding to the reference setting So; obtaining the stereo pair of images from at least one camera of the optical system; warping the stereo pair of images into images corresponding to the reference setting So, and using the surface profile reconstruction parameters to determine the surface profile. In a particular embodiment, the surface profile is passed to a computer model of tissue deformation and used to determine an intra-surgery location of a tumor or other anatomic feature of tissue.

Method and apparatus for calibration of stereo-optical three-dimensional surface-mapping system

A system and method for determining intraoperative locations of a lesion in tissue from lesion locations determined in preoperative imaging includes determining three dimensional locations of surface features of the organ in the preoperative images. A preoperative surface map is extracted from stereo images annotated with surface features from preoperative images. An intraoperative surface map of the organ is extracted from stereo images, and surface features are identified in the stereo images corresponding to surface features annotated into the preoperative surface map. Three dimensional displacements of the surface features are determined and used to constrain a computer model of deformation of the organ. In embodiments, the model of deformation is adapted or constrained to model locations and dimensions of surgical cavities using an optical flow method and/or locations of surgical instruments in the organ. The model of deformation is used to determine intraoperative locations for the lesion.

Method and apparatus for determining tumor shift during surgery using a stereo-optical three-dimensional surface-mapping system

A method for providing patient registration without fiducials comprises the steps of: spatially placing an ultrasound image of a patient randomly at different starting positions relative to a preoperative image; creating an independent registration corresponding to each different starting positions, by optimizing a spatial transformation between the preoperative image and the ultrasound image to provide a first batch of registrations; executing a second registration to fine-tune the alignment between the preoperative image and the ultrasound image; and concatenating the spatial transformation to obtain spatial transformation between the patient in an operating room and a corresponding preoperative image.

System and method for providing patient registration without fiducials

A system and methods are presented for emulating the appearance of prominent features captured in ultrasound through directional dilation of a magnetic resonance gradient image along a direction determined by the relative ultrasound scan-head location with respect to the magnetic resonance gradient image in order to improve the robustness and reliability of registration.

Growing community of inventors

Hanover, NH, United States of America

Songbai Ji