Systems and methods for tracking positions between imaging modalities and transforming a displayed three-dimensional image corresponding to a position and orientation of a probe
View Patent ↗Systems and methods are provided for transforming a displayed three-dimensional image corresponding to a position and orientation of a field of view of an imaging probe. A three dimensional image of a tissue in a first co-ordinate space can be displayed. A field of view of an imaging probe in a second co-ordinate space can be configured, where the imaging probe has a plurality of transmitters removably connected to it, the transmitters operable to determine the position and orientation of the field of view relative to the positions of the transmitters in the second co-ordinate space. The first and second co-ordinate spaces can be co-registered, and the position and orientation of the field of view in the second co-ordinate space can be transformed to the first co-ordinate space. The three-dimensional image can be displayed to correspond to the transformed position and orientation of the field of view.
1. A method for calibrating a field of view of an imaging probe relative to a plurality of transmitters removably connected to the imaging probe, the method comprising:
positioning an end of a configuration tool at a plurality of configuration positions on a transducer of the imaging probe, the configuration tool having at least one transmitter;
recording a location of the configuration tool at each of the plurality of configuration positions; and
determining a calibration matrix based on the recorded location of the configuration tool at each of the plurality of configuration positions, without using image information from the imaging probe, wherein the calibration matrix relates a transducer co-ordinate frame to a transmitter coordinate frame, and wherein the transducer co-ordinate frame has an origin (O) at a center of a face of the transducer, the origin determined from the recorded location of the configuration tool at each of the plurality of configuration positions.
2. A method for calibrating a field of view of an imaging probe relative to a plurality of transmitters removably connected to the imaging probe, the method comprising:
positioning an end of a configuration tool at a plurality of configuration positions on a transducer of the imaging probe, the configuration tool having at least one transmitter;
recording a location of the configuration tool at each of the plurality of configuration positions; and
determining a calibration matrix based on the recorded location of the configuration tool at each of the plurality of configuration positions,
wherein the calibration matrix relates a transducer co-ordinate frame to a transmitter co-ordinate frame,
wherein the transducer co-ordinate frame has an origin (O) at a center of a face of the transducer, and
wherein the calibration positions are corners of the transducer.
3. The method of claim 2 , wherein the calibration matrix is a 4×4 matrix and is determined by:
determining the origin (O) specified in co-ordinates in the transmitter co-ordinate frame;
determining a first vector (X) that is normal to transducer of the imaging probe at the origin (O) specified in co-ordinates in the transmitter co-ordinate frame;
determining a second vector (Z) that is parallel to the transducer of the imaging probe and containing the origin (O) specified in co-ordinates in the transmitter co-ordinate frame;
determining a third vector (Y) that is orthogonal to the first and second vectors and containing the origin (O) specified in co-ordinates in the transmitter co-ordinate frame; and
defining the transformation matrix as [X Y Z O; 0 0 0 1] capable of relating the transducer co-ordinate frame to the transmitter co-ordinate frame.
4. The method of claim 3 , wherein the transducer is curvilinear in shape and the method further comprises shifting the position of the origin (O) to compensate for the curvilinear shape of the face of the transducer.
5. The method of claim 3 , further comprising determining whether the first vector (X) points toward an image plane of the transducer of the imaging probe.
6. The method of claim 5 , further comprising negating the first vector (X), when the first vector (X) does not point toward the image plane of the transducer of the imaging probe.
7. The method of claim 3 , wherein determining a second vector (Z) comprises:
determining an upper vector defined by the upper left and upper right corner points;
determining a lower vector defined by the lower left and lower right corner points; and
averaging the upper and lower vectors to obtain the second vector (Z).
8. The method of claim 3 , further comprising determining whether the third vector (Y) is directed in a negative direction.
9. The method of claim 8 , further comprising negating the third vector (Y), when the third vector (Y) is directed in a negative direction to form a right handed coordinate system.