Patent ID: 9560291
Date: 2017-01-31
CPC Classifications: A61B,H04N

Claim:
1. A method using a system including a computer, a phantom, a tracking system and an imaging device, wherein a registration mapping is provided that combines data indicative of spatial positions in a three-dimensional operating space and imaging data acquired with the imaging device located in a second position and orientation in operating space referred to as an imaging pose, the method comprising: a) orienting the imaging device with the phantom in a first position and orientation in the operating space, referred to as a first pose, wherein the phantom is at least in partial view of the imaging device located in a second pose, the phantom comprising a marker assembly having a plurality of markers that can be imaged by the imaging device, using X-ray dense and/or X-ray opaque crosses and/or symbols arranged in a predetermined pattern as marker elements on the marker assembly, and changing a characteristic of the marker elements to form the X-ray dense and/or X-ray opaque crosses and/or symbols; b) acquiring by the imaging device image data of the marker assembly with the imaging device disposed in the second pose; c) identifying by the computer imaged markers in the image data of the marker assembly acquired by the imaging device and determining by the computer first marker positions of the imaged markers identified by the computer; d) determining by the computer second marker positions by applying the registration mapping to spatial positions of the plurality of markers of the marker assembly determined by the tracking system with the phantom in the first pose using the second pose as the imaging pose; e) determining a distance measure of the first marker positions and the second marker positions, wherein the distance measure represents spatial differences between said first marker positions and said second marker positions by positive, non-zero values; f) transforming the imaging pose used in the registration mapping to a different imaging pose, of the imaging device, using a rigid body transformation reducing the distance measure, if the distance measure is outside a predetermined threshold; and g) determining whether two consecutive distance measures of the imaging poses approach one another up to the predetermined threshold or until a predetermined convergence criterion is met, thereby calibrating the imaging device.