Hybrid navigation system for tracking the position of body tissue

Abstract

A hybrid surgical navigation system for tracking the position of body tissue. The system includes a marker shaped to be mounted subcutaneously to the tissue the position of which is to be tracked. A tracker located above skin level is placed near the marker. A first navigation system integral with the marker and tracker generate data indicating the position of the marker relative to the tracker. A second navigation monitors the position of the tracker. The tracker also includes a transmitter for transmitting data generated by the first navigation system. Based on the data generated by the first navigation system representative of the position of the marker relative to the tracker and the data from the second navigation system representative of the position of the tracker, the position of the marker and tissue to which it is attached is determined.

Description

FIELD OF THE INVENTION [0001] This invention relates generally to a surgical navigation system used to track the position of body tissue. More particularly, this invention relates to a surgical navigation for tracking body tissue that does not expose the tissue to excessive trauma and that can be used in the presence of ferromagnetic objects. BACKGROUND OF THE INVENTION [0002] Surgical navigation systems are increasingly used as aids in surgical procedures. Generally, a surgical navigation includes a tracker, a localizer and a processor. The tracker is attached to an instrument or section of tissue the position of which is to be tracked. The localizer, relative to the tracker, is static. One or more transmitters are contained in either the tracker or localizer. The other of localizer or the tracker contains one or more complementary receives able to detect the energy emitted by the transmitters. It is known to construct surgical navigation systems out of transmitter receiver pairs w...

AI Technical Summary

Benefits of technology

[0011] This invention is related to a new and useful hybrid surgical navigation system for tracking the position of body tissue. The system and method of this invention are designed to minimize trauma to the tissue it is used to track and can be used without appreciably limiting the introduction of ferromagnetic devices into the surgical field.

[0016] In the system of this invention, the tracker head and tissue marker are separated by distances of 15 cm or less. Therefore, the signals exchanged between the tracker head and tissue marker are of relatively low strength. This makes it possible to provide a tracker head that is small in size. Consequently, only a minimal incision is needed to fit the marker. Further, only low strength energy needs to be transmitted transcutaneously, through the body. These features collectively minimize the trauma to which the patient's body is exposed when the system and method of this invention is employed.

[0017] Still another feature of the low power requirement of this invention is that a battery is typically all that is required to power the tracker. Therefore, the need to introduce an addition power cord near the patient is eliminated

[0018] Further there is only a relatively small space between the tissue marker and the tracker. This means a ferromagnetic object may be placed relatively close to the components of this system without adversely affecting the accuracy of the tracker position and orientation data generated by the system.

Problems solved by technology

This is because, if the tracker moves relative to the tissue, the system may not generate signals that accurately represent tissue position.

Having to so mount the tracker to the bone appreciably adds to the trauma to which the patient is exposed when required to undergo a surgical procedure.

While the above proposed system offers some benefits, there are some limitations associated with its use.

This requirement limits the utility of this system.

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