FIELD: physics.
SUBSTANCE: group of inventions relates to electromagnetic tracking systems for tracking a medical device and methods of compensating for local error due to distortions caused by metal, using said systems. The tracking system has an electromagnetic field generator which generates an electromagnetic field to obtain data on location of a medical device by inducing current in the sensor coil of the medical device, and an error correction instrument. The latter has three electromagnetic sensors installed in a given configuration. The error correction instrument performs a function for correcting errors from the detected locations and based on the given configuration of the three electromagnetic sensors for correcting location data of the medical device. When using the tracking system in one of the versions, an electromagnetic field is generated, data on location of the medical device in a human body is monitored using current induced by the electromagnetic field in the electromagnetic sensor coil of the medical device, and location data of three electromagnetic sensors is monitored. The error correction instrument lies near the medical device and the three electromagnetic sensors lie in a given and fixed configuration. Further, a correction function is established from the obtained data and then applied to said location data of the medical device to compensate for distortions caused by metal. In another version for compensating for error due to distortions, when tracking the location of the medical device, an electromagnetic field is generated by one electromagnetic field generator having a first optical sensor; a first platform for supporting the medical procedure is used, having a second optical sensor; a positioning system is used and compensation mapping is performed. The positioning system contains the sensor of the electromagnetic tracking system. Compensation mapping involves movement of the positioning system to different locations within the required spatial volume; compensating for the location of the medical device taking into account distortions caused by metal based on the given location of the electromagnetic field generator and said first platform relative said positioning system.
EFFECT: use of the group of inventions enables to increase efficiency of compensating for distortions and accuracy of electromagnetic tracking systems (EMTS).
18 cl, 3 dwg
