MRI-safe high impedance lead systems
First Claim
Patent Images
1. An MRI/RF compatible medical lead, comprising:
- an elongate flexible body;
a plurality of conductors extending along the elongate flexible body, each of the conductors comprising a plurality of axially spaced apart coiled segments and a plurality of linear segments with the linear segments disposed between adjacent coiled segments;
at least two electrodes disposed on a distal portion of the elongate flexible body, each electrode coupled to a different one of the plurality of conductors;
wherein the lead defines a plurality of high impedance RF traps spaced apart along a length of the elongate flexible body, each high impedance RF trap comprising at least one coiled segment of each of two or more of the plurality of conductors, wherein each high impedance RF trap is configured and arranged to inhibit flow of induced RF current at a first frequency, wherein the first frequency is at least 1 MHz, and each high impedance RF trap is configured and arranged to allow stimulation signals having a frequency of 1 kHz or less to pass through the high impedance RF trap.
3 Assignments
0 Petitions
Accused Products
Abstract
Some embodiments are directed to MRI/RF compatible medical interventional devices. A plurality of spaced apart high impedance circuit segments are configured to have a high impedance at a high range of radiofrequencies and a low impedance at a low range of frequencies. The high impedance circuit segments may comprise co-wound coiled inductors and can reduce, block or inhibit RJ-transmission along the lead system (20) during exposure to RF associated with a high-Held magnet MRI systems, while permuting passage of low frequency physiologic signals, treatments and/or stimuli. The devices can include at least one electrode.
139 Citations
20 Claims
-
1. An MRI/RF compatible medical lead, comprising:
-
an elongate flexible body; a plurality of conductors extending along the elongate flexible body, each of the conductors comprising a plurality of axially spaced apart coiled segments and a plurality of linear segments with the linear segments disposed between adjacent coiled segments; at least two electrodes disposed on a distal portion of the elongate flexible body, each electrode coupled to a different one of the plurality of conductors; wherein the lead defines a plurality of high impedance RF traps spaced apart along a length of the elongate flexible body, each high impedance RF trap comprising at least one coiled segment of each of two or more of the plurality of conductors, wherein each high impedance RF trap is configured and arranged to inhibit flow of induced RF current at a first frequency, wherein the first frequency is at least 1 MHz, and each high impedance RF trap is configured and arranged to allow stimulation signals having a frequency of 1 kHz or less to pass through the high impedance RF trap. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. An MRI/RF compatible medical lead, comprising:
-
an elongate flexible body; a first electrode disposed near an end of the flexible body; a second electrode disposed near the end of the flexible body; a first axially extending conductor extending along the flexible body and coupled to the first electrode; a second axially extending conductor extending along the flexible body and coupled to the second electrode; and a plurality of spaced apart capacitors; wherein, at each of a plurality of intermediate locations along at least a major portion of a length of the lead, at least one of the capacitors is disposed between the first and second axially extending conductors to define a plurality of high impedance circuit segments, each high impedance circuit segment comprising at least a portion of the first axially extending conductor, at least a portion of the second axially extending conductor, and at least one of the plurality of spaced apart capacitors, wherein each of the plurality of high impedance circuit segments is configured as an RF trap that inhibits flow of induced RF current at a target range of high frequencies to inhibit heating tissue adjacent to the first and second electrodes, wherein high frequencies are frequencies at or above 1 MHz, whereby the lead has a high impedance at the target range of high frequencies and a low impedance at low frequencies. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19)
-
-
20. A system, comprising:
-
an implantable pulse generator comprising a housing;
a high impedance decoupling circuit disposed in the housing; and
a controller disposed in the housing; andat least one implantable lead coupleable to the implantable pulse generator and to the decoupling circuit, the lead comprising at least one electrode disposed thereon; wherein the controller is configured to selectively activate the decoupling circuit to provide, when the lead is coupled to the implantable pulse generator, a high impedance to the lead at high radio frequencies and a low impedance at low radio frequencies, wherein the controller is remotely controllable to activate the decoupling circuit to provide the high impedance.
-
Specification