Abstract: Systems and methods for operating steerable sheath (SS). The methods comprise: causing an inner shaft (IS) to move in a first direction (FD) relative to an outer shaft (OS) having a first lumen (FL) in which IS is disposed; applying tension to a first pull wire (FPW) as IS moves in FD (FPW being partially disposed in a wall of IS and in FL of OS, FPW's first end being connected to IS and FPW's second end being connected to OS); allowing a deflectable region of IS's wall to transition from a straight state to a deflected state as tension is applied to FPW; causing IS to move in a second direction relative to OS; removing the tension being applied to FPW as IS moves in the second direction; and allowing the deflectable region of IS's wall to return to the straight state as tension is being removed from FPW.

Abstract: An MR compatible injection catheter is provided. The MR compatible injection catheter includes an inner shaft; an outer shaft circumferentially surrounding the inner shaft; and a means for actively tracking the catheter in a patient within a MRI. The means for actively tracking the catheter includes two or more tracking coils in the outer shaft. The inner shaft is configured to move relative to the outer shaft and includes an inner tube circumferentially surrounded by an outer tube.

Abstract: A method for producing a magnetic resonance image of a subject tissue to identify a lesion or scar tissue thereon in provided. The method includes acquiring an initial three-dimensional image of the subject tissue by a computer-implemented MRI system; identifying the surface of the subject tissue by the computer-implemented MRI system; selecting one or more points on the surface of the subject tissue by the computer-implemented MRI system; and acquiring by the computer-implemented MRI system, a first two-dimensional image for at least one of the selected points that is substantially tangential to the surface of the selected point.

Abstract: A method for projecting a broad tracking signal received by an inductively coupled element, such as a transformer during an MR tracking sequence is provided. By varying projection planes, the signal acquired from the transformer along the transmission line can be used to depict the body of the actively tracked medical device, such as the shaft or deflection region of a catheter. This may be achieved by interpolating a line between the position of the transformer element within the transmission line and the tracking coil. A curvature may be added to the line segment and gradually increased until the arc length of the line segment is approximately equal to the predefined length. The direction of the curve may be determined by virtually connecting the transformer position to the distal most tracking coil position, then the curve of the line segment is increased towards the proximal coil position.

Abstract: A method for projecting a broad tracking signal received by an inductively coupled element, such as a transformer during an MR tracking sequence is provided. By varying projection planes, the signal acquired from the transformer along the transmission line can be used to depict the body of the actively tracked medical device, such as the shaft or deflection region of a catheter. This may be achieved by interpolating a line between the position of the transformer element within the transmission line and the tracking coil. A curvature may be added to the line segment and gradually increased until the arc length of the line segment is approximately equal to the predefined length. The direction of the curve may be determined by virtually connecting the transformer position to the distal most tracking coil position, then the curve of the line segment is increased towards the proximal coil position.

Abstract: An actively tracked medical device comprising: a dilator having an inner tubular main body having a distal end and a proximal end, said tubular main body including at least first and second receiving channels positioned in a spaced apart relationship on an outer surface of said tubular main body; a region at the distal end of said tubular main body for supporting one or more tracking coils; an atrumatic tip portion operably coupled and positioned distal to said main body; a lumen extending through said tubular main body, said tip support and said atraumatic tip portion; and an outer polymer body having first and second ends, said outer polymer body operably covering said inner tubular main body and said tracking coils, said first end terminating adjacent a proximal end of said atraumatic tip portion and said second end terminating adjacent said hub.

Abstract: A composite tracking system for a medical device comprises a field location tracking system including at least one field location sensor structured to be coupled to a medical device, a magnetic resonance tracking system including at least one tracking coil structured to be coupled to a medical device, and a composite tracking processor operably coupled to the field location tracking system and the magnetic resonance tracking system. The composite tracking processor is operable to receive and process field location parameters from the field location tracking system and positional coordinates from the magnetic resonance tracking system to register a field location coordinate system to a magnetic resonance coordinate system.

Abstract: A composite tracking system for a medical device comprises a field location tracking system including at least one field location sensor structured to be coupled to a medical device, a magnetic resonance tracking system including at least one tracking coil structured to be coupled to a medical device, and a composite tracking processor operably coupled to the field location tracking system and the magnetic resonance tracking system. The composite tracking processor is operable to receive and process field location parameters from the field location tracking system and positional coordinates from the magnetic resonance tracking system to register a field location coordinate system to a magnetic resonance coordinate system.

Abstract: A method of calibrating field location tracking to magnetic resonance tracking is provided. The method of calibration field location tracking includes moving a medical device throughout a plurality of points within a patient volume; tracking the medical device with a field location tracking system and a magnetic resonance tracking system; calculating a plurality of magnetic resonance tracking locations; determining a plurality of field location parameters that correspond to the plurality of magnetic resonance tracking locations; and creating a transfer function that maps the field location parameters to the magnetic resonance tracking locations, wherein the transfer function registers a field location coordinate system to a magnetic resonance coordinate system.

Abstract: An MR compatible steerable sheath with a slidable valve adaptor is provided. The slidable valve adaptor is configured to maintain the steerable shaft in a proximal position such that there is slack in first and second longitudinal movement wires when the valve adaptor is in a first position, and is configured to remove slack from the first and second longitudinal movement wires when the valve adaptor is slidably moved to the second position. Slidable valve adaptor also optionally includes a safety cap that prevents insertion of a catheter into the control handle until the valve adaptor is in the distal position.

Abstract: A method of using a MR compatible deflectable catheter is provided. The MR compatible deflectable catheter includes a steerable sheath having a tubular shaft. The tubular shaft receives first and second longitudinal movement wires at a distal end thereof. A control handle is coupled to a proximal end of the first and second longitudinal movement wires and causes longitudinal movement of the wires. Longitudinal movement of the wires causes the catheter to deflect approximately 180 degrees.

Abstract: A temperature monitoring system for a medical device comprises an optical transmit/receive unit, an elongate optical fiber having a proximal end, a distal end, and an inner core extending between the proximal end and the distal end, and one or more fiber Bragg grating elements formed in the inner core of the optical fiber. The optical fiber is operably coupled to the transmit/receive unit at the proximal end. At least a portion of the optical fiber is also operably coupled to a medical device and is structured to measure temperature at one or more temperature sensing locations on the medical device.

Abstract: An MR compatible deflectable catheter and method of using the same is provided. The MR compatible deflectable catheter includes a steerable sheath having a tubular shaft. The tubular shaft receives first and second longitudinal movement wires at a distal end thereof. A control handle is coupled to a proximal end of the first and second longitudinal movement wires and causes longitudinal movement of the wires.

Abstract: A method of using a MR compatible deflectable catheter is provided. The MR compatible deflectable catheter includes a steerable sheath having a tubular shaft. The tubular shaft receives first and second longitudinal movement wires at a distal end thereof. A control handle is coupled to a proximal end of the first and second longitudinal movement wires and causes longitudinal movement of the wires. Longitudinal movement of the wires causes the catheter to deflect approximately 180 degrees.

Abstract: An MRI compatible electrode circuit construct is provided. The construct includes at least two filter components constructed from an electrode wire. One filter component may be a resonant LC filter at or near an electrode/wire interface that resolves the issue of insufficient attenuation by effectively blocking the RF induced current on the wire from exiting the wire through the electrode. The second filter component may include one or more non-resonant filter(s) positioned along the length of the electrode wire that resolve(s) the issue of excessive heating of the resonant LC filter by significantly attenuating the current induced on the wire before it reaches the resonant LC filter. The non-resonant filter(s) may also attenuate the RF current reflected from the resonant LC filter thereby resolving the issue of the strong reflected power from the resonant filter and the associated dielectric heating.

Abstract: An MRI compatible lead assembly construct is provided. The construct includes at least two filter components constructed from an electrode wire. One filter component may be a resonant LC filter proximate an electrode that resolves the issue of insufficient attenuation by effectively blocking the RF induced current on the wire from exiting the wire through the electrode. The second filter component may include a non-resonant filter(s) positioned along the length of the electrode wire by co-radially winding at least two electrode wires. The non-resonant filter resolve(s) the issue of excessive heating of the resonant LC filter by significantly attenuating the current induced on the wire before it reaches the resonant LC filter.

Abstract: An MRI compatible lead assembly construct is provided. The construct includes at least two filter components constructed from an electrode wire. One filter component may be a resonant LC filter at or near an electrode/wire interface that resolves the issue of insufficient attenuation by effectively blocking the RF induced current on the wire from exiting the wire through the electrode. The second filter component may include one or more non-resonant filter(s) positioned along the length of the electrode wire that resolve(s) the issue of excessive heating of the resonant LC filter by significantly attenuating the current induced on the wire before it reaches the resonant LC filter. The non-resonant filter(s) may also attenuate the RF current reflected from the resonant LC filter thereby resolving the issue of the strong reflected power from the resonant filter and the associated dielectric heating.

Abstract: An MRI compatible electrode circuit construct is provided. The construct includes at least two filter components constructed from an electrode wire. One filter component may be a single or multiple layer resonant LC filter positioned proximate an electrode that resolves the issue of insufficient attenuation by effectively blocking the RF induced current on the wire from exiting the wire through the electrode. The second filter component may include one or more non-resonant filter(s) positioned along the length of the electrode wire that resolve(s) the issue of excessive heating of the resonant LC filter by significantly attenuating the current induced on the wire before it reaches the resonant LC filter. The resonant LC filter may also be positioned distal to the end of the non-resonant filters with the non-resonant filters proximate the electrode.

Abstract: An MRI compatible cable construct is provided. The cable is adapted to be used with a medical device in direct electrical contact with a patient. Each cable or cable set includes a plurality of filter components. The filter component comprises at least two filter components. One filter component may be a resonant filter at a distal end that resolves the issue of insufficient attenuation by effectively blocking the RF induced current on the cable from exiting the cable at the distal. The second filter component may comprise one or more non-resonant filter(s) or inductors positioned along the length of the cable that resolve(s) the issue of excessive heating of the resonant LC filter by significantly attenuating the current induced on the cable before it reaches the resonant LC filter.

Abstract: An MRI compatible electrode circuit construct is provided. The construct includes at least two filter components constructed from an electrode wire. One filter component may be a resonant LC filter at or near an electrode/wire interface that resolves the issue of insufficient attenuation by effectively blocking the RF induced current on the wire from exiting the wire through the electrode. The second filter component may include one or more non-resonant filter(s) positioned along the length of the electrode wire that resolve(s) the issue of excessive heating of the resonant LC filter by significantly attenuating the current induced on the wire before it reaches the resonant LC filter. The non-resonant filter(s) may also attenuate the RF current reflected from the resonant LC filter thereby resolving the issue of the strong reflected power from the resonant filter and the associated dielectric heating.