System and method for optical position measurement and guidance of a rigid or semi-flexible tool to a target
AssigneeActiviews Ltd.
InventorPinhas Gilboa
Life of this patent
Estimating the term…
Abstract
A system for measuring the position of a hand-held tool relative to a body in six degrees of freedom employs a camera attached via a mechanical linkage to the tool so that the camera moves together with the proximal portion of the tool and has a field of view including the distal end of the tool. A processing system processes images from the camera to determine a position of at least part of the tool. By employing optically identifiable fiducial reference points defined on the external surface of the body, a projection of the tool tip position onto a plane containing the target can be derived and displayed together with the target position, thereby facilitating guiding the tool to the target.
Claims32
A system for measuring the position of a hand-held tool relative to a body in at least five degrees of freedom, the system comprising:
- (a) a rigid or semi-flexible tool having a distal end for insertion into the body, and a proximal portion for manual manipulation outside the body;
- (b) a marker arrangement comprising a patch configured to be applied to an external surface of the body at a point of insertion of the tool into the body, said patch carrying a plurality of fiducial points;
- (c) a camera for generating images;
- (d) a mechanical linkage mounting said camera on said proximal portion of said tool such that:
- (i) said camera moves together with said proximal portion of said tool, and
- (ii) said camera is directed with a field of view including at least part of said patch when said patch is deployed on an external surface of the body and said distal portion of said tool in inserted into the body;
- and
- (e) a processing system in data communication with said camera and configured to process images from said camera to determine a position of at least part of said tool relative to said fiducial points.
A method for guiding a distal end of a rigid or semi-flexible tool to a target within a body, the tool having a proximal portion for manual manipulation from outside the body, the method comprising the steps of:
- (a) determining a spatial relation between a plurality of optically identifiable fiducial reference points defined on an external surface of the body and the target;
- (b) providing a camera mechanically attached to the proximal portion of the tool;
- and
- (c) during insertion of the tool into the body:
- (i) obtaining from the camera images of the external surface of the body including a plurality of said fiducial points,
- (ii) deriving from positions of said fiducial points in said images a current tip projection corresponding substantially to a point of intersection between an extrapolation from the distal end of the tool taken in a pointing direction of the distal end with a plane containing the target and substantially perpendicular to the pointing direction of the distal end of the tool, and
- (iii) displaying a graphic representation of at least the position of the target and the current tip projection.
A method for guiding a distal end of a semi-flexible tool to a target within a body, the tool having a proximal portion for manual manipulation from outside the body, the method comprising the steps of:
- (a) employing a position tracking system to monitor a current position of the proximal portion of the tool;
- (b) determining a location of penetration of the tool into the body;
- (c) deriving from said current position of the proximal portion of the tool and from said location of penetration an estimation of flexion of the tool, and hence a current tip position of the distal end of the tool within the body;
- and
- (d) displaying a graphic representation of at least:
- (i) the position of the target, and)
- (ii) the intersection of an extrapolation from the distal end of the tool taken in a pointing direction of the distal end with a plane containing the target and substantially perpendicular to the pointing direction of the distal end.
A patch for attachment to the skin of a body for use together with an optical guidance system for guiding a distal end of a rigid or semi-flexible tool to a target within a body, the tool having a proximal portion for manual manipulation from outside the body, the patch comprising:
- (a) a lower surface for adhering temporarily to the skin;
- (b) an upper surface provided with a set of at least four optically detectable fiducial points;
- (c) a plurality of contrast-generating features configured to provide high contrast points under operation of a non-optical imaging system for enabling localization of the patch using a non-optical imaging system;
- and
- (d) an insertion configuration configured to delineate a point of penetration of the distal end of the tool into the body.
Dependencies are inferred from the claim text.