Method for calibrating a navigation system
First Claim
1. A method for calibrating an electromagnetic navigation system having a transmitter coil array that generates an electromagnetic field in a procedure region, said method comprising:
- (a) positioning the electromagnetic navigation system in a working environment having a metallic object outside of the procedure region of the electromagnetic field that causes a metallic distortion in the electromagnetic field in the procedure region, wherein an instrument is positionable in the procedure region within a portion of the electromagnetic field;
(b) positioning a calibration sensor at a first calibration point in the procedure region of the working environment;
(c) energizing a first coil in the transmitter coil array to generate a first field of the electromagnetic field;
(d) sensing a first field strength of the first field with the calibration sensor in the procedure region; and
(e) positing the calibration sensor at a second calibration point in the procedure region of the working environment and repeating (c) and (d) at the second calibration point, wherein effects of the metallic distortion caused by the metallic object are taken into account during the calibration and wherein the metallic object is a medical device.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and apparatus for electromagnetic navigation of a surgical probe near a metal object. The electromagnetic navigation system includes a transmitter coil array and a shield. The transmitter coil array has a plurality of transmitter coils and is operable to generate the electromagnetic field to navigate the probe. The shield is positioned adjacent the metal object and is operable to shield the metal object from the electromagnetic field generated by the transmitter coil array, such that the shield substantially reduces distortion of the electromagnetic field by the metal object.
-
Citations
44 Claims
-
1. A method for calibrating an electromagnetic navigation system having a transmitter coil array that generates an electromagnetic field in a procedure region, said method comprising:
-
(a) positioning the electromagnetic navigation system in a working environment having a metallic object outside of the procedure region of the electromagnetic field that causes a metallic distortion in the electromagnetic field in the procedure region, wherein an instrument is positionable in the procedure region within a portion of the electromagnetic field; (b) positioning a calibration sensor at a first calibration point in the procedure region of the working environment; (c) energizing a first coil in the transmitter coil array to generate a first field of the electromagnetic field; (d) sensing a first field strength of the first field with the calibration sensor in the procedure region; and (e) positing the calibration sensor at a second calibration point in the procedure region of the working environment and repeating (c) and (d) at the second calibration point, wherein effects of the metallic distortion caused by the metallic object are taken into account during the calibration and wherein the metallic object is a medical device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19)
-
-
20. A method for calibrating an electromagnetic navigation system having a transmitter coil array that generates an electromagnetic field in a three dimensional space, said method comprising:
-
positioning a metallic object adjacent at least a procedure region of the electromagnetic field; positioning a calibration sensor at a first calibration point in the three dimensional space, energizing a plurality of coils sequentially in the transmitter coil array to generate a plurality of fields of the electromagnetic field; sensing first field strengths of each of the plurality of fields with the calibration sensor at the first calibration point; and moving the calibration sensor to a second calibration point in the three dimensional space different from the first calibration point, energizing the plurality of coils sequentially in the transmitter coil array to generate the plurality of fields; sensing second field strengths of each of the plurality of fields with the calibration sensor at the second calibration point; and storing the sensed first field strengths and the second field strengths; wherein effects of metallic distortion caused by the metallic object is taken into account during the calibrating at least by sensing the generated first field strengths and second field strengths that include distortion due to the metallic object. - View Dependent Claims (21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 33, 34, 35, 36, 41, 42, 43, 44)
-
-
32. A method for calibrating an electromagnetic navigation system having a transmitter coil array integral with a metallic object that generates an electromagnetic field in a three dimensional space, said method comprising:
-
operating the transmitter coil array that is integral with the metallic object that generates the electromagnetic field in the three dimensional space; positioning a calibration sensor at a calibration position in three dimensional space; instructing a coil array controller to drive a particular coil in the transmitter coil array to generate at least a portion of the electromagnetic field that includes metallic distortion effect due to the metallic object; sensing at least a portion of the electromagnetic field having the metallic distortion effect with the calibration sensor at the calibration position; determining an electromagnetic field strength of the sensed at least a portion of the electromagnetic field having the metallic distortion effect for the calibration position by a navigation probe interface; and storing the determined electromagnetic field strength at the calibration position with a storage device; wherein effects of metallic distortion effect caused by the metallic object is taken into account during the calibrating at least by sensing the generated at least a portion of the electromagnetic field that includes distortion due to the metallic object. - View Dependent Claims (37, 38, 39, 40)
-
Specification