Device and method for a trackable ultrasound
First Claim
1. A method of adjusting a calibration of a tracked ultrasound device, wherein the tracked ultrasound device includes a tracker and a scan head, wherein the tracker includes one or more tracker fiducial markings and one or more sensor elements, wherein the scan head has at least one scan plane originating therefrom and includes one or more scan head fiducial markings, the method comprising:
- attaching the tracker to the scan head in a first position;
calculating an initial calibration transformation matrix that relates the one or more sensor elements to the at least one scan plane, such that the position and orientation of the one or more sensor elements enables determination of the position and orientation of the at least one scan plane;
determining a first relative position of the one or more tracker fiducial markings in relation to the one or more scan head fiducial markings when the tracker is attached to the scan head in the first position;
moving the tracker relative to the scan head into a second position;
determining a second relative position of the one or more tracker fiducial markings in relation to the one or more scan head fiducial markings when the tracker is attached to the scan head in the second position;
calculating a difference between the first and second relative positions of the tracker fiducial markings and the scan head fiducial markings; and
adjusting the initial calibration transformation matrix using the calculated difference between the first and second relative positions of the tracker fiducial markings and the scan head fiducial markings.
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Accused Products
Abstract
The invention provides a method for adjusting the calibration of a tracked ultrasound device using the measured difference between two sets of fiducial markings in two relative positions of a tracker and an scan head of the device. The invention also provides a trackable ultrasound device that enables repeatable attachment of a tracker to a scan head, thus preserving an initial calibration between the tracker and the scan head. Furthermore, the invention provides a calibration jig that can be used to repeatably attach a tracker to an ultrasound scan head or to measure the difference between two relative positions of a tracker and a scan head.
230 Citations
14 Claims
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1. A method of adjusting a calibration of a tracked ultrasound device, wherein the tracked ultrasound device includes a tracker and a scan head, wherein the tracker includes one or more tracker fiducial markings and one or more sensor elements, wherein the scan head has at least one scan plane originating therefrom and includes one or more scan head fiducial markings, the method comprising:
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attaching the tracker to the scan head in a first position; calculating an initial calibration transformation matrix that relates the one or more sensor elements to the at least one scan plane, such that the position and orientation of the one or more sensor elements enables determination of the position and orientation of the at least one scan plane; determining a first relative position of the one or more tracker fiducial markings in relation to the one or more scan head fiducial markings when the tracker is attached to the scan head in the first position; moving the tracker relative to the scan head into a second position; determining a second relative position of the one or more tracker fiducial markings in relation to the one or more scan head fiducial markings when the tracker is attached to the scan head in the second position; calculating a difference between the first and second relative positions of the tracker fiducial markings and the scan head fiducial markings; and adjusting the initial calibration transformation matrix using the calculated difference between the first and second relative positions of the tracker fiducial markings and the scan head fiducial markings. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. A method for repeatable replacement of a tracker onto an ultrasound device, wherein the tracker includes at least one sensor element and one or more tracker alignment elements, wherein the ultrasound device includes a scan head and one or more scan head alignment elements, wherein at least one scan plane originates from the scan head, and wherein each of the one or more tracker alignment elements corresponds to one of the one or more scan head alignment elements, the method comprising:
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calibrating the at least one scan plane to the at least one sensor element when the tracker is attached to the scan head in a first position, such that the position and orientation of the at least one scan plane is determinable from the position and orientation of the at least one sensor element; removing the tracker from the scan head; re-attaching the tracker to the scan head; placing the tracker and the scan head into a calibration jig that includes one or more calibration jig alignment elements that each correspond to at least one tracker alignment element or scan head alignment element and aligning each of the one or more calibration jig alignment elements to its corresponding tracker alignment element or scan head alignment element causing the tracker to be aligned onto the scan head in the first position. - View Dependent Claims (13, 14)
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Specification