Magnetic resonance probes
View Patent ↗A magnetic resonance probe may include a plurality of center conductors, at least some center conductors including a conductive core and an insulator disposed at least partially about the core along at least a portion of the core, a first dielectric layer disposed at least partially about the plurality of center conductors in a proximal portion of the probe, an outer conductive layer at least partially disposed about the first dielectric layer, and a plurality of electrodes, at least one electrode being coupled to one of the center conductors and disposed at least partly on a probe surface.
1. A magnetic resonance probe, comprising:
a plurality of center conductors, at least some center conductors;
including a conductive core and an insulator disposed at least partially about the core along at least a portion of the core; and
forming a first pole of a magnetic resonance dipole antenna;
a first dielectric layer disposed at least partially about the plurality of center conductors in a proximal portion of the probe;
an outer conductive layer at least partially disposed about the first dielectric layer and forming a second pole of the magnetic resonance dipole antenna; and
a plurality of electrodes, at least one electrode being coupled to one of the center conductors and disposed at least partly on a probe surface.
2. The probe of claim 1 , further comprising a second dielectric layer at least partially disposed about the outer conductive layer.
3. The probe of claim 1 , further comprising a lubricious coating at least partially disposed about the outer conductive layer.
4. The probe of claim 1 , wherein the plurality of center conductors are magnetic resonance-compatible.
5. The probe of claim 1 , wherein at least one insulator has a thickness equal to or less than about 100 microns.
6. The probe of claim 1 , wherein at least some center conductors comprise at least one of a magnetic resonance compatible material, a super elastic material, copper, silver-copper, gold, silver, platinum, iridium, MP35N, tantalum, titanium, Nitinol, L605, gold-platinum-iridium, gold-copper-iridium, and gold-platinum.
7. The probe of claim 1 , further comprising a connection to a high-pass filter through which the probe is coupleable to a magnetic resonance scanner.
8. The probe of claim 1 , further comprising a connection to a low-pass filter through which the probe is coupleable to at least one of an electrophysiological recording system, a tissue stimulator, and an ablation energy source.
9. The probe of claim 1 , further comprising:
a ribbon disposed in a distal portion of the probe; and
a pull wire coupled to the ribbon.
10. The probe of claim 9 , wherein the pull wire is disposed in a lumen in the probe.
11. The probe of claim 1 , further comprising a coolant lumen.
12. The probe of claim 1 , further comprising a plurality of radially expandable arms, wherein at least one electrode is at least partly disposed on one arm.
13. The probe of claim 12 , further comprising a tubing that is slideably displaceable between at least two positions to transition the expandable arms between a retracted position and an expanded position.
14. The probe of claim 12 , further comprising a tubing that is slideably displaceable between at least two positions to transition the expandable arms between a retracted position and an expanded position.
15. The probe of claim 1 , further comprising an ablation electrode disposed at a distal tip of the probe.
16. The probe of claim 1 , further comprising an interface circuit coupled to the probe, the interface circuit including:
a signal splitter that directs a signal received from the probe to a magnetic resonance pathway and an electrophysiology pathway;
a high-pass filter disposed in the magnetic resonance pathway;
a low-pass filter disposed in the electrophysiology pathway;
a connector disposed in the magnetic resonance pathway for connecting to a magnetic resonance scanner; and
a connector disposed in the electrophysiology pathway for connecting to at least one of a tissue stimulator, a biopotential recording system, and an ablation energy source.
17. The probe of claim 1 , wherein the probe has an outer diameter of less than about 15 French.
18. The probe of claim 1 , wherein the probe has an outer diameter of less than about 4 French.
19. The probe of claim 1 , further comprising a connector portion disposed at a proximal end of the probe, the connector portion including:
an outer conductor contact coupled to the outer conductive layer;
extended sections of at least some center conductors extending proximally beyond the outer conductor contact, at least one extended section having a center conductor contact coupled to one center conductor; and
an insulated area interposed between the outer conductor contact and the at least one center conductor contact.
20. The probe of claim 1 , defining at least one lumen.
21. The probe of claim 20 , further comprising a pull wire disposed in the lumen, coupled to a distal portion of the probe, and longitudinally displaceable.
22. The probe of claim 1 , wherein at least one center conductor is coupled to a distal portion of the probe and longitudinally displaceable.
23. The probe of claim 1 , wherein all of the center conductors collectively form the first pole of the magnetic resonance dipole antenna.
24. A method of performing a magnetic resonance-guided procedure, comprising:
placing a subject in a magnetic resonance scanner;
identifying a target site in the subject using data about the subject obtained from the scanner;
introducing into the patient a magnetic resonance probe as defined by claim 1 ;
advancing the probe to the target site; and
performing the procedure using the magnetic resonance probe.
25. The method of claim 24 , wherein the target site is located in the subject's brain, and the probe is introduced by employing a stereotactic frame.
26. The method of claim 24 , wherein the target site comprises at least one of the subject's thalamus, globus pallidum internus, and subthalamic nucleus.
27. The method of claim 24 , further comprising anchoring at least one of the probe's electrodes in the subject.
28. The method of claim 24 , further comprising electrically connecting at least one of the probe's electrodes to a pacemaker.
29. The method of claim 24 , wherein the target site is located in the subject's heart.
30. The method of claim 29 , wherein at least one probe electrode is an RF ablation electrode, and the method further comprises ablating heart tissue.
31. The method of claim 30 , wherein ablating comprises creating a plurality of linear ablations in the subject's left and/or right atrium.
32. A combined magnetic resonance imaging and electrophysiology probe, comprising:
a plurality of center conductors, at least some center conductors including a conductive core and an insulator disposed at least partially about the core along at least a portion of the core, the insulator having a thickness equal to or less than about 100 microns;
a first dielectric layer disposed at least partially about the plurality of center conductors in a proximal portion of the probe;
an outer conductive layer at least partially disposed about the first dielectric layer;
a second dielectric layer disposed at least partially about the outer conductive layer; and
a plurality of electrodes, at least one electrode coupled to one of the center conductors and disposed at least partly on the probe surface.
33. A system for magnetic resonance imaging, comprising:
a magnetic resonance probe, including:
a plurality of center conductors, at least some center conductors:
including a conductive core and an insulator disposed at least partially about the core along at least a portion of the core; and
forming a first pole of a magnetic resonance dipole antenna;
a first dielectric layer disposed at least partially about the plurality of center conductors in a proximal portion of the probe;
an outer conductive layer disposed at least partially about the first dielectric layer and forming a second pole of the magnetic resonance dipole antenna; and
a plurality of electrodes, at least one electrode coupled to one of the center conductors and disposed at least partly on the probe surface; and
a interface electrically coupled to the probe, the interface including:
a signal splitter that directs a signal received from the probe to a magnetic resonance pathway and an electrophysiology pathway;
a high-pass filter disposed in the magnetic resonance pathway;
a low-pass filter disposed in the electrophysiology pathway;
a connector disposed in the magnetic resonance pathway for connecting to a magnetic resonance scanner; and
a connector disposed in the electrophysiology pathway for connecting to at least one of a tissue stimulator, a electrophysiological recording system, and an ablation energy source.