Abstract: Systems and methods for collecting and processing physical space data for use while performing an image-guided surgical (IGS) procedure are provided. The system and method includes obtaining a computer model of a non-rigid structure of interest in a patient and performing a rigid alignment of the computer model and surface data in a patient space associated with at least a portion of the non-rigid structure. The system and method also include computing a deformation of the computer model that provides a non-rigid alignment of the computer model and surface data, the deformation computed using a set of boundary conditions defined for each node of the computer model based on the rigid alignment and a kernel function. Additionally, the system and method can include displaying data for facilitating the IGS procedure based on the deformation.

Abstract: Methods and systems for performing trackerless image guided soft tissue surgery. For a patient in need of brain surgery, pre-operative preparation for a patient is performed by generating a three-dimensional textured point cloud (TPC) for the patient's scalp surface, and registering the first three-dimensional TPC to a magnetic resonance (MR) model of the brain. During the surgery, an intra-operative cortical surface registration to the MR model is performed for the MR-to-cortical surface alignment. Then shift measurement and compensation to the MR model is performed by: performing absolute deformation measurement of the brain based on the MR model with the cortical surface registration, and obtaining shift correction to the MR model using the absolute deformation measurements. The shift correction may be used for adjusting an image guidance system (IGS) in the brain surgery.

Abstract: A method for image guided surgery includes obtaining intraoperative locations including intraoperative fiducial locations for a non-rigid structure and intraoperative rigid structure locations for associated rigid structures, estimating a gravity deformation for the non-rigid structure based on a first rigid registration for preoperative fiducial locations in a computer model relative to the intraoperative fiducial locations and a second rigid registration for the preoperative rigid structure locations for a rigid structure in the computer model with respect to the intraoperative rigid structure locations, modifying the preoperative fiducial locations using first rigid registration and the gravity deformation, determining a third rigid registration for the modified fiducial locations relative to the intraoperative fiducial locations, calculating a non-rigid transformation for the computer model using the volumetric gravity field deformation and first boundary conditions from errors in the third rigid registra

Abstract: Systems and methods are provided for collecting and processing physical space data for use while performing an image-guided surgical (IGS) procedure. A method includes performing a rigid alignment of a computer model of a non-rigid structure of interest in a patient and surface data in a patient space associated with at least a portion of said non-rigid structure, and computing a deformation of the computer model that provides a non-rigid alignment of said computer model and an organ geometric representation of data, said deformation computed using a set of boundary conditions and field variables defined for said computer model based on said rigid alignment and a parameterization function.

Abstract: A method for image guided surgery includes obtaining intraoperative locations including intraoperative fiducial locations for a non-rigid structure and intraoperative rigid structure locations for associated rigid structures, estimating a gravity deformation for the non-rigid structure based on a first rigid registration for preoperative fiducial locations in a computer model relative to the intraoperative fiducial locations and a second rigid registration for the preoperative rigid structure locations for a rigid structure in the computer model with respect to the intraoperative rigid structure locations, modifying the preoperative fiducial locations using first rigid registration and the gravity deformation, determining a third rigid registration for the modified fiducial locations relative to the intraoperative fiducial locations, calculating a non-rigid transformation for the computer model using the volumetric gravity field deformation and first boundary conditions from errors in the third rigid registra

Abstract: Systems and methods for collecting and processing physical space data for use while performing an image-guided surgical (IGS) procedure are provided. The system and method includes obtaining a computer model of a non-rigid structure of interest in a patient and performing a rigid alignment of the computer model and surface data in a patient space associated with at least a portion of the non-rigid structure. The system and method also include computing a deformation of the computer model that provides a non-rigid alignment of the computer model and surface data, the deformation computed using a set of boundary conditions defined for each node of the computer model based on the rigid alignment and a kernel function. Additionally, the system and method can include displaying data for facilitating the IGS procedure based on the deformation.

Abstract: A method for real-time correction of tissue compression for tracked ultrasound includes acquiring an ultrasound image of tissues of interest with an ultrasound probe having a probe surface, where the ultrasound probe is tracked to provide a position and an orientation of the probe surface of the ultrasound probe for the acquired ultrasound image; acquiring intraoperative measurements of the undeformed tissue surface; constructing a generic grid representation of tissues for use with a mathematical model of tissue biomechanics, where the generic grid representation is pre-aligned to the acquired ultrasound image by performing a calibration to the ultrasound probe; determining boundary conditions to the mathematical model represented by the generic grid representation; solving the mathematical model for 3D displacements in the generic grid representation of the tissues; and performing correction of tissue compression by using the reversed and interpolated 3D displacement field on the acquired ultrasound image.

Abstract: Systems and methods for collecting and processing physical space data for use while performing an image-guided surgical (IGS) procedure are provided. The system and method includes obtaining a computer model of a non-rigid structure of interest in a patient and performing a rigid alignment of the computer model and surface data in a patient space associated with at least a portion of the non-rigid structure. The system and method also include computing a deformation of the computer model that provides a non-rigid alignment of the computer model and surface data, the deformation computed using a set of boundary conditions defined for each node of the computer model based on the rigid alignment and a kernel function. Additionally, the system and method can include displaying data for facilitating the IGS procedure based on the deformation.

Abstract: Methods and systems for performing trackerless image guided soft tissue surgery. For a patient in need of brain surgery, pre-operative preparation for a patient is performed by generating a three-dimensional textured point cloud (TPC) for the patient's scalp surface, and registering the first three-dimensional TPC to a magnetic resonance (MR) model of the brain. During the surgery, an intra-operative cortical surface registration to the MR model is performed for the MR-to-cortical surface alignment. Then shift measurement and compensation to the MR model is performed by: performing absolute deformation measurement of the brain based on the MR model with the cortical surface registration, and obtaining shift correction to the MR model using the absolute deformation measurements. The shift correction may be used for adjusting an image guidance system (IGS) in the brain surgery.

Abstract: A method for real-time correction of tissue compression for tracked ultrasound includes acquiring an ultrasound image of tissues of interest with an ultrasound probe having a probe surface, where the ultrasound probe is tracked to provide a position and an orientation of the probe surface of the ultrasound probe for the acquired ultrasound image; acquiring intraoperative measurements of the undeformed tissue surface; constructing a generic grid representation of tissues for use with a mathematical model of tissue biomechanics, where the generic grid representation is pre-aligned to the acquired ultrasound image by performing a calibration to the ultrasound probe; determining boundary conditions to the mathematical model represented by the generic grid representation; solving the mathematical model for 3D displacements in the generic grid representation of the tissues; and performing correction of tissue compression by using the reversed and interpolated 3D displacement field on the acquired ultrasound image.

Abstract: A method and system of compensation for intra-operative organ shift of a living subject usable in image guide surgery. In one embodiment, the method includes the steps of generating a first geometric surface of the organ of the living subject from intra-operatively acquired images of the organ of the living subject, constructing an atlas of organ deformations of the living subject from pre-operatively acquired organ images from the pre-operatively acquired organ images, generating a second geometric surface of the organ from the atlas of organ deformations, aligning the second geometric surface of the organ to the first geometric surface of the organ of the living subject to determine at least one difference between a point of the first geometric surface and a corresponding point of the second geometric surface of the organ of the living subject, which is related to organ shift, and compensating for the intra-operative organ shift.

Abstract: Systems and methods are provided for collecting and processing physical space data for use while performing an image-guided surgical (IGS) procedure. A method includes performing a rigid alignment of a computer model of a non-rigid structure of interest in a patient and surface data in a patient space associated with at least a portion of said non-rigid structure, and computing a deformation of the computer model that provides a non-rigid alignment of said computer model and an organ geometric representation of data, said deformation computed using a set of boundary conditions and field variables defined for said computer model based on said rigid alignment and a parameterization function.

Abstract: A method and system of compensation for intra-operative organ shift of a living subject usable in image guide surgery. In one embodiment, the method includes the steps of generating a first geometric surface of the organ of the living subject from intra-operatively acquired images of the organ of the living subject, constructing an atlas of organ deformations of the living subject from pre-operatively acquired organ images from the pre-operatively acquired organ images, generating a second geometric surface of the organ from the atlas of organ deformations, aligning the second geometric surface of the organ to the first geometric surface of the organ of the living subject to determine at least one difference between a point of the first geometric surface and a corresponding point of the second geometric surface of the organ of the living subject, which is related to organ shift, and compensating for the intra-operative organ shift.

Abstract: Systems and methods for collecting and processing physical space data for use while performing an image-guided surgical (IGS) procedure are provided. The system and method includes obtaining a computer model of a non-rigid structure of interest in a patient and performing a rigid alignment of the computer model and surface data in a patient space associated with at least a portion of the non-rigid structure. The system and method also include computing a deformation of the computer model that provides a non-rigid alignment of the computer model and surface data, the deformation computed using a set of boundary conditions defined for each node of the computer model based on the rigid alignment and a kernel function. Additionally, the system and method can include displaying data for facilitating the IGS procedure based on the deformation.

Abstract: A cortical surface registration procedure related to a diagnostic or surgical procedure. In one embodiment, the procedure includes the steps of pre-operatively obtaining a first textured point cloud of the cortical surface of a targeted region of a brain of a living subject, intra-operatively obtaining optically a second textured point cloud of the cortical surface of the brain of the living subject, and aligning the first textured point cloud of the cortical surface to the second textured point cloud of the cortical surface so as to register images of the brain of the living subject to the cortical surface of the living subject.

Abstract: A method and system of compensation for intra-operative organ shift of a living subject usable in image guide surgery. In one embodiment, the method includes the steps of generating a first geometric surface of the organ of the living subject from intra-operatively acquired images of the organ of the living subject, constructing an atlas of organ deformations of the living subject from pre-operatively acquired organ images from the pre-operatively acquired organ images, generating a second geometric surface of the organ from the atlas of organ deformations, aligning the second geometric surface of the organ to the first geometric surface of the organ of the living subject to determine at least one difference between a point of the first geometric surface and a corresponding point of the second geometric surface of the organ of the living subject, which is related to organ shift, and compensating for the intra-operative organ shift.

Abstract: An image reconstruction algorithm begins with an initial acquisition of a preoperative imaging volume followed by a second imaging sequence subsequent to an applied deformation. A computational domain (model) is generated from the preoperative image series and boundary conditions are derived from a pre-post deformation comparison, as well as from information gathered from deformation source application (i.e., displacement and/or force). Using boundary conditions, a series of model-based image deformations is accomplished while varying model material properties. A calculation of a Jacobian matrix relating the change in regional mutual information is performed with respect to the change in material properties. Upon completion of this process, matrix regularization techniques are used to condition the system of equations and allow for inversion and subsequent delivery of model-property adjustments.

Abstract: A cortical surface registration procedure related to a diagnostic or surgical procedure. In one embodiment, the procedure includes the steps of pre-operatively obtaining a first textured point cloud of the cortical surface of a targeted region of a brain of a living subject, intra-operatively obtaining optically a second textured point cloud of the cortical surface of the brain of the living subject, and aligning the first textured point cloud of the cortical surface to the second textured point cloud of the cortical surface so as to register images of the brain of the living subject to the cortical surface of the living subject.

Abstract: A method of compensation for intra-operative brain shift of a living subject. In one embodiment, the method includes the steps of pro-operatively acquiring brain images of the living subject, constructing a statistical atlas of brain displacements of the living subject from the pro-operatively acquired brain images, intra-operatively measuring brain displacements of the living subject, deriving an intra-operative displacement atlas from the intra-operatively measured brain displacements and the statistical atlas, obtaining intra-operative brain shift at least from the intra-operative displacement atlas, and compensating for the intra-operative brain shift.

Abstract: A method and apparatus for collecting and processing physical space data used while performing image-guided surgery is disclosed. Physical space data is collected by probing physical surface points of surgically exposed tissue. The physical space data provides three-dimensional (3-D) coordinates for each of the physical surface points. Based on the physical space data collected, point-based registrations used to indicate surgical position in both image space and physical space are determined. In one embodiment, the surface of surgically exposed tissue of a living patient is illuminated with laser light. Light reflected from the illuminated surface of the exposed tissue is received and analyzed. In another embodiment, one or more magnetic fields of known shape and size are established in the proximity of the exposed tissue. Data associated with the strength of the magnetic fields is acquired and analyzed.