Patent Description:
Some medical procedures such as magnetic resonance imaging and remote catheter navigation use a magnetic field. The presence of other magnetic fields during these procedures can cause interference, which can affect correct imaging and placement of various medical devices. It would be beneficial to quickly identify if magnetic and electro-magnetic interference is present before these procedures take place as well as the direction of magnetic and electro-magnetic interference. Disclosed herein are a system, apparatus and method of use that addresses the foregoing. <CIT> discloses a system for facilitating endotracheal intubation that includes one or more magnetometers arranged relative to a video laryngoscope body and configured to generate magnetometer signals based on an interaction with one or more magnetic elements associated with an intubation device. <CIT> discloses tissue expander containing a magnet and a device for detecting the magnet.

Disclosed herein is a system for magnetic field direction detection when placing a catheter according to claim <NUM>.

In some embodiments, the system includes a console wired to the sensor.

In some embodiments, the system includes a console wirelessly coupled to the sensor.

In some embodiments, the system includes a console in communication with the display.

In some embodiments, the system includes a console including one or more thresholds corresponding to a measured strength of the magnetic field source at a known distance from the sensor.

In some embodiments, the sensor is configured to be placed on a body of a patient and perform a medical device tip location tracking process.

Also disclosed but not claimed, is an apparatus for magnetic field direction detection when placing a catheter including a sensor housing, a magnetic sensor printed circuit board (PCB), coupled to the sensor housing, having a plurality of magnetometers arranged in a magnetometer array, where the magnetic sensor PCB provides, to a console device, a magnetic field strength value detected by each magnetometer and a magnetometer ID of a corresponding magnetometer where the magnetic field strength values and corresponding magnetometer IDs indicate a direction of the magnetic field source relative to the apparatus based on a positioning of each magnetometer and the magnetic field strength value detected by each magnetometer.

In some embodiments, the apparatus includes a PCB including a rectangular arranged magnetometer array.

In some embodiments, the apparatus includes a PCB including an elliptical arranged magnetometer array.

According to a second aspect, there is provided a method according to claim <NUM>.

In some embodiments, the method includes detecting a magnetic field by a sensor includes recording an identifier of each magnetometer in the plurality of magnetometers and detected magnetic field strength value at each magnetometer in the plurality of magnetometers.

In some embodiments, the method includes generating a graphic includes generating one or more of a reference icon, a magnetic field source icon or a magnetic field source direction icon.

In some embodiments, generating a graphic includes generating a graphic that illustrates the magnetic field source is no longer detected by the sensor.

In some embodiments, generating a graphic includes generating a graphic that receives user input confirming the magnetic field source has been removed.

It is appreciated that the invention is defined by the appended claims.

Before some particular embodiments are disclosed in greater detail, it should be understood that the invention is defind by the appended claims.

In the following description, certain terminology is used to describe aspects of the invention. For example, in certain situations, the term "logic" is representative of hardware, firmware or software that is configured to perform one or more functions. As hardware, logic may include circuitry having data processing or storage functionality. Examples of such circuitry may include, but are not limited or restricted to a hardware processor (e.g., microprocessor with one or more processor cores, a digital signal processor, a programmable gate array, a microcontroller, an application specific integrated circuit "ASIC," etc.), a semiconductor memory, or combinatorial elements.

Alternatively, logic may be software, such as executable code in the form of an executable application, an Application Programming Interface (API), a subroutine, a function, a procedure, an applet, a servlet, a routine, source code, object code, a shared library/dynamic load library, or one or more instructions. The software may be stored in any type of a suitable non-transitory storage medium, or transitory storage medium (e.g., electrical, optical, acoustical or other form of propagated signals such as carrier waves, infrared signals, or digital signals). Examples of non-transitory storage medium may include, but are not limited or restricted to a programmable circuit; semiconductor memory; non-persistent storage such as volatile memory (e.g., any type of random access memory "RAM"); or persistent storage such as non-volatile memory (e.g., read-only memory "ROM," power-backed RAM, flash memory, phase-change memory, etc.), a solid-state drive, hard disk drive, an optical disc drive, or a portable memory device. As firmware, the executable code may be stored in persistent storage.

<FIG> illustrates a plan view of a system <NUM> for magnetic field direction detection when placing a catheter including a console <NUM> coupled to a sensor <NUM> including a magnetic sensor printed circuit board ("PCB") <NUM> with a plurality of magnetometers <NUM> in a magnetometer array <NUM>, in accordance with some embodiments. In some embodiments, the system <NUM> includes the console <NUM> having a processor <NUM> and non-transitory computer readable medium ("memory") <NUM> having a plurality of logic modules that are configured to perform operations that will be described in more detail. In some embodiments, the console <NUM> can be coupled to a display <NUM> on which graphics can be generated to illustrate the direction of a magnetic field source <NUM> including one or more of a sensor icon <NUM>, a magnetic field source icon <NUM>, or a magnetic field source direction icon <NUM>. In some embodiments, the sensor <NUM> may be configured to be placed on a body of a patient and perform a medical device tip location tracking process. In some embodiments, the sensor <NUM> includes a sensor housing <NUM> coupled to the magnetic sensor PCB <NUM> having a plurality of magnetometers <NUM> arranged in a magnetometer array <NUM> configured to detect the presence of a magnetic field source <NUM> through detection of a magnetic field generated thereby.

The magnetic sensor PCB <NUM> may be configured such that each of the plurality of magnetometers <NUM> in a magnetometer array <NUM> measures a magnetic field strength, where each measurement is communicated to the console <NUM>. The magnetic sensor PCB <NUM> communicates a series of magnetic field strength measurements (e.g., values) with a magnetometer ID of the corresponding magnetometer <NUM> in the magnetometer array <NUM> to the console <NUM>. In some embodiments, the console <NUM> may be configured to receive the magnetic field strength measurements from the plurality of magnetometers <NUM> and to determine the direction of the magnetic field source <NUM> based on the received magnetic field strength measurements. Once the console <NUM> has determined the direction of the magnetic field source <NUM>, the console <NUM> may be configured to indicate the direction of the magnetic field source <NUM> on the display <NUM> through generating a graphic that may include one or more of the reference icon <NUM>, the magnetic field source icon <NUM> or the direction icon <NUM>. In some embodiments, the reference icon <NUM> can include an icon of a sensor, a rectangle, an X, a circle, or the like. In some embodiments, the magnetic field source icon <NUM> can include an icon of a bar magnet, an icon of a horseshoe magnet, an icon of a cylindrical magnet or the like. In some embodiments, the direction icon <NUM> can include an arrow, a line, a finger or the like. In some embodiments, the reference icon <NUM> may be configured to be centered on the display <NUM> with the magnetic field source icon <NUM> and the direction icon <NUM> being located <NUM>° around the reference icon <NUM>, with the direction icon <NUM> being displayed in the direction the console <NUM> has determined for the magnetic field source <NUM> (see <FIG>).

illustrates a block diagram depicting various elements of the system for magnetic field direction detection when placing a catheter including the console <NUM> and the sensor <NUM> including the magnetic sensor PCB <NUM> coupled to the sensor housing <NUM>, having a plurality of magnetometers <NUM> arranged in a magnetometer array <NUM>. The console <NUM> is shown to include one or more processors <NUM>, a communication interface <NUM>, the display <NUM> and the memory" <NUM>, having a plurality of logic modules including a magnetometer acquisition logic <NUM>, a magnetic field source determination logic <NUM> and a display logic <NUM>. In some embodiments, the console <NUM> includes the memory <NUM>, which when executed by the processor <NUM> can be configured to perform operations including receiving magnetic field strength values detected by the plurality of magnetometers <NUM>, determining a position on the sensor of each of the plurality of magnetometers <NUM>, determining a direction of a magnetic field source <NUM> relative to the sensor <NUM> based on the detected magnetic field strength values and the position on the sensor <NUM> of each of the plurality of magnetometers <NUM>, and generating a graphic configured to illustrate the direction of the magnetic field source200 on the display <NUM>. Further, the memory <NUM> may optionally include data stores such as magnetic field source direction data <NUM>, magnetometer measurement data <NUM> and the relation data <NUM>.

In some embodiments, the magnetometer acquisition logic <NUM> receives communications from the sensor <NUM> including the magnetic sensor PCB <NUM>, wherein the communications may be a series of magnetic field strength measurement values paired with a magnetometer ID of the corresponding magnetometer <NUM> in the magnetometer array <NUM>. In some embodiments, the communication may also include a location within the magnetometer array <NUM> along with the magnetic field strength measurement value and the magnetometer ID (i.e. a tuple). Alternatively, the magnetometer acquisition logic <NUM> performs a lookup for the location of a magnetometer <NUM> in the magnetometer array <NUM> based on the magnetometer ID in order to complete the {magnetic field strength, magnetometer ID, magnetometer location} tuple. In some embodiments, the magnetometer ID corresponds to the physical location of each of the plurality of magnetometers <NUM> in the magnetometer array <NUM>. the magnetometer acquisition logic <NUM> is configured to determine the position on the sensor <NUM> of each of the plurality of magnetometers <NUM> based on the magnetometer ID of each of the plurality of magnetometers <NUM> arranged in the magnetometer array <NUM>.

In some embodiments, the magnetic field source determination logic <NUM> determines the magnetic field source direction, relative to the sensor <NUM>, using the magnetometer ID from each of the plurality of magnetometers <NUM> and the measured magnetic field strength values by each magnetometer <NUM>. For instance, in some embodiments, the magnetic field source determination logic <NUM> determines a direction of the magnetic field source <NUM> relative to the sensor <NUM>, using at least one threshold that will be described in more detail herein. The magnetic field source determination logic <NUM> correlates each magnetometer ID with the magnetic field strength value measured at each of the plurality of magnetometers <NUM> within the magnetometer array <NUM>. In some embodiments, the display logic <NUM> is configured to generate a graphic configured to illustrate the direction of the magnetic field source direction on the display <NUM> using one of a plurality of icons including the reference icon <NUM>, the magnetic field source icon <NUM> or a magnetic field source direction icon <NUM>.

In some embodiments, the processor <NUM> includes non-volatile memory such as EEPROM for instance, thus acting as a control processor. The display <NUM> in the present embodiment may be integrated into the console <NUM> and is used to display information about a magnetic field source <NUM> to the clinician while using the system <NUM>. In another embodiment, the display <NUM> may be separate from the console <NUM> and may be communicatively coupled by way of a wired communication or a wireless communication including WiFi, Bluetooth, Near Field Communications (NFC), electromagnetic (EM), radio frequency (RF), combinations thereof, or the like.

In some embodiments, the sensor <NUM> including the magnetic sensor PCB <NUM> is coupled to the console <NUM>. In some embodiments, the sensor <NUM> including the magnetic sensor PCB <NUM> can be in wired communication with the console <NUM>. In some embodiments, the console <NUM> including the magnetic sensor PCB <NUM> can be communicatively coupled by way of wireless communication. Exemplary wireless communication modalities can include WiFi, Bluetooth, Near Field Communications (NFC), electromagnetic (EM), radio frequency (RF), combinations thereof, or the like.

In some embodiments, the magnetic sensor PCB <NUM>, coupled to the sensor housing <NUM>, can include a plurality of magnetometers <NUM> arranged in various configurations in a magnetometer array <NUM>. As illustrated in <FIG>, the plurality of magnetometers <NUM> can be arranged in a rectangular configuration on the magnetic sensor PCB <NUM>, coupled to the sensor housing <NUM>. If a magnetic field source <NUM> is present, the plurality of magnetometers <NUM> in the magnetometer array <NUM> are each configured to measure the magnetic field source strength. If a magnetic field source <NUM> is located on the proximal side of the magnetic sensor PCB <NUM>, as illustrated in <FIG>, the plurality of magnetometers <NUM> located proximal the magnetic field source <NUM> will detect higher magnetic field strength values as compared to the plurality of magnetometers <NUM> located distal the magnetic field source <NUM>, which will detect lower magnetic field strength values. In an alternative embodiment, the plurality of magnetometers <NUM> can be arranged in an elliptical configuration magnetometer array <NUM> on the magnetic sensor PCB <NUM> coupled to the sensor housing <NUM>, as illustrated in <FIG>.

In some embodiments, a system <NUM> for magnetic field direction detection when placing a catheter can detect the direction of the magnetic field source <NUM> and distance of the magnetic field source <NUM>. <FIG> illustrates a block diagram depicting various elements of the system <NUM> for magnetic field direction detection when placing a catheter including one or more distance thresholds correlating to the measured strength of the magnetic field source at different distances in relation to the sensor <NUM>, in accordance with some embodiments. In this embodiment, the system <NUM> includes the console <NUM> including the processor <NUM> and memory <NUM> having stored thereon a plurality of logic modules that, when executed by the processor <NUM> are configured to perform operation including receiving magnetic field strength values detected by the plurality of magnetometers <NUM>, determining the position on the sensor <NUM> including the magnetic sensor PCB <NUM> coupled to the sensor housing <NUM>, of each of the plurality of magnetometers <NUM>, determining the direction of a magnetic field source <NUM> relative to the sensor <NUM> based on the detected magnetic field strength values and the position on the sensor <NUM> of each of the plurality of magnetometers <NUM>, determining a distance, relative to the sensor <NUM>, based on one or more thresholds, and generating the graphic configured to illustrate the direction of the magnetic field source <NUM> on a display <NUM>. In some embodiments, the console <NUM> is shown to include the one or more processors <NUM>, the communication interface <NUM>, the display <NUM> and the non-transitory, computer-readable medium ("memory") <NUM>. In some embodiments, the memory <NUM> is configured to store logic modules including the magnetometer acquisition logic <NUM>, the magnetic field source determination logic <NUM>, a magnetic field threshold distance logic <NUM>, and a display logic <NUM>. Further, the memory <NUM> may optionally include data stores such as the magnetic field source direction data <NUM>, a magnetic field source distance data <NUM>, the magnetometer measurement data <NUM> and the relation data <NUM>.

In this embodiment, the magnetometer acquisition logic <NUM> and the magnetic field source determination logic <NUM> function as described above. In this embodiment, the magnetic field threshold distance logic <NUM> compares a magnetic field reading from the plurality of magnetometers <NUM> in the magnetometer array <NUM> to one or more established thresholds corresponding to one or more established distances of a magnetic field source <NUM> from the sensor <NUM> including the magnetic sensor PCB <NUM> as described above. In this embodiment, the magnetic field threshold distance logic <NUM> compares magnetic field reading values to a first established threshold corresponding to a magnetic field strength within a first distance <NUM> ("d<NUM>") away from the sensor <NUM> including the magnetic sensor PCB <NUM>, to a second established threshold corresponding to the magnetic field strength within a second distance <NUM> ("d<NUM>") away from the sensor <NUM> including the magnetic sensor PCB <NUM>, to a third established threshold corresponding to the magnetic field strength within a third distance <NUM> ("d<NUM>") away from the sensor <NUM> including the magnetic sensor PCB <NUM>, and a fourth established threshold corresponding to the magnetic field strength within a fourth distance <NUM> ("d<NUM>") away from the sensor <NUM> including the magnetic sensor PCB <NUM>. Although four distances corresponding to four thresholds are illustrated, the invention is defined by the appended claims.

As one example, if the magnetic field strength falls within the first established threshold, the magnetic field source is within the first distance <NUM> from the sensor <NUM> including the magnetic sensor PCB <NUM>. If the magnetic field strength falls within the third established threshold, the magnetic field source is within the third distance <NUM> from the sensor including the magnetic sensor PCB <NUM>. In this embodiment, the display logic <NUM> is configured to generate a graphic configured to illustrate the direction of the magnetic field source direction and the distance of the magnetic field source using a plurality of icons including the reference icon <NUM>, the magnetic field source icon <NUM>, the magnetic field source direction icon <NUM>, and a magnetic field source distance icon <NUM> on the display <NUM>. Further, the magnetic field source direction icon <NUM> may indicate the distance from the sensor <NUM> including the magnetic sensor PCB <NUM> to the detected magnetic field source <NUM>. For example, as shown in <FIG>, the magnetic field source direction icon <NUM> includes the magnetic field source distance icon <NUM> being the text "<NUM> (4ft). " The indication of the distance may refer to an approximate distance between the sensor <NUM> and the detected magnetic field source <NUM>, while in other embodiments, the indication of the distance may utilize one or more thresholds (e.g., <NUM>-<NUM> (<NUM>-6ft). " where such an indication corresponds to a particular distance threshold).

In some embodiments, the system <NUM> may be configured to detect the direction of a local magnetic field that may interfere with magnetic tracking devices such as devices and systems for navigation and position a central venous catheter within a patient which can be found, for example, in <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT>.

For example, the system <NUM> may include a console <NUM> having logic coupled to memory <NUM>, a display <NUM>, and a sensor <NUM> including a magnetic sensor PCB <NUM> having a plurality magnetometers <NUM> arranged in a magnetometer array <NUM> configured to track the tip of a medical device for proper placement including in some embodiments, a stylet, a wire, or a catheter. In some placement procedures, the sensor <NUM> may be configured to track the tip of the medical device by measuring a local electromagnetic field. However, a hospital bed can include a remote control (e.g., a magnetic field source <NUM>) or other electronic devices (e.g. cell phones, tables), which can interfere with the sensor <NUM> configured to track the tip of the medical device by producing a magnetic field and potentially leading to improper placement of the medical device. The magnetic sensor PCB <NUM> including the plurality of magnetometers <NUM> arranged in the magnetometer array <NUM> can be configured to measure the magnetic field strength at each of the plurality of magnetometers <NUM> and can be communicated to the console <NUM>. The console <NUM> can be configured to receive the magnetic field strength measurement values from the plurality of magnetometers <NUM> and determine, using the logic coupled to memory as described above, to determine the direction of the magnetic field source <NUM> (e.g., the hospital bed remote control) based upon the magnetic field strength measurement values. The console <NUM> may then alert the user by indicating the direction of the magnetic field source <NUM> (e.g., the hospital bed remote control) as it relates to the sensor <NUM> on the display <NUM> by the use of one or more of the reference icon <NUM>, the magnetic field source icon <NUM> or the magnetic field source direction icon <NUM>.

<FIG> illustrates an exemplary method <NUM> of detecting a magnetic field before placing a catheter, in accordance with some embodiments. The method <NUM> includes detecting a magnetic field by a sensor <NUM> configured to be placed on a body of a patient and perform a medical device tip location tracking process, the sensor <NUM> including a magnetic sensor PCB <NUM> printed circuit board (PCB) including a plurality of magnetometers <NUM> arranged in a magnetometer array <NUM> (block <NUM>). In some embodiments, the detecting a magnetic field by a sensor <NUM> includes an optional step of recording an identifier of each magnetometer in the plurality of magnetometers <NUM> and detected magnetic field strength value at each magnetometer in the plurality of magnetometers <NUM> (block <NUM>). In some embodiments, the magnetometer array <NUM> may be arranged in a rectangular shape, an elliptical shape or the like. The method <NUM> further includes correlating the detected magnetic field strength values with a position on the sensor <NUM>, of each of the plurality of magnetometers <NUM> as arranged in magnetometer array <NUM> (block <NUM>). In some embodiments, the correlating includes a console <NUM> or the sensor <NUM> including the magnetic sensor PCB <NUM> having the plurality of magnetometers <NUM> arranged in a magnetometer array <NUM> providing a magnetometer ID that corresponds each of the plurality of magnetometers <NUM> in the magnetometer array <NUM>. In some embodiments, the console <NUM> correlates the magnetometer ID with the magnetic field strength values measured at the one or more magnetometers <NUM> in the magnetometer array <NUM>.

The method <NUM> further includes determining a direction of the magnetic field source <NUM> relative to the sensor <NUM>, wherein the determining is based on the correlating of the detected magnetic field strength values at each of the plurality of magnetometers <NUM> and the position on the sensor <NUM> of each of the plurality of magnetometers <NUM> (block <NUM>).

Claim 1:
A system for magnetic field direction detection when placing a catheter comprising:
a sensor configured to track a medical device, the sensor including a magnetic sensor printed circuit board, PCB (<NUM>), including a plurality of magnetometers (<NUM>) arranged in a magnetometer array (<NUM>); and
a console (<NUM>) coupled to the sensor (<NUM>), the console including a processor and non-transitory computer-readable medium having stored thereon a plurality of logic modules that, when executed by the processor, are configured to perform operations including:
receiving magnetic field strength values detected by the plurality of magnetometers (<NUM>);
determining a position of each of the plurality of magnetometers (<NUM>) on the sensor based on a magnetometer ID of each of the plurality of magnetometers arranged in the magnetometer array (<NUM>);
determining a direction of a magnetic field source relative to the sensor (<NUM>) based on the detected magnetic field strength values and the position on the sensor of each of the plurality of magnetometers (<NUM>);
generating a graphic configured to illustrate the direction of the magnetic field source on a display (<NUM>); and
correlating each magnetometer ID with the magnetic field strength value measured at each of the plurality of magnetometers (<NUM>) within the magnetometer array (<NUM>).