摘要:
A multilayer helical wave filter having a primary resonance at a selected RF diagnostic or therapeutic frequency or frequency range, includes an elongated conductor forming at least a portion of an implantable medical lead. The elongated conductor includes a first helically wound segment having at least one planar surface, a first end and a second end, which forms a first inductive component, and a second helically wound segment having at least one planar surface, a first end and a second end, which forms a second inductive element. The first and second helically wound segments are wound in the same longitudinal direction and share a common longitudinal axis. Planar surfaces of the helically wound segments face one another, and a dielectric material is disposed between the facing planar surfaces of the helically wound segments and between adjacent coils of the helically wound segments, thereby forming a capacitance.
摘要:
A shielded three-terminal flat-through EMI/energy dissipating filter includes an active electrode plate through which a circuit current passes between a first terminal and a second terminal, a first shield plate on a first side of the active electrode plate, and a second shield plate on a second side of the active electrode plate opposite the first shield plate. The first and second shield plates are conductively coupled to a grounded third terminal. In preferred embodiments, the active electrode plate and the shield plates are at least partially disposed with a hybrid flat-through substrate that may include a flex cable section, a rigid cable section, or both.
摘要:
A multilayer helical wave filter having a primary resonance at a selected MRI RF pulsed frequency or frequency range, includes an elongated conductor forming at least a portion of an implantable medical lead. The elongated conductor includes a first helically wound segment having at least one planar surface, a first end and a second end, which forms a first inductive component, and a second helically wound segment having at least one planar surface, a first end and a second end, which forms a second inductive element. The first and second helically wound segments are wound in the same longitudinal direction and share a common longitudinal axis. Planar surfaces of the helically wound segments face one another, and a dielectric material is disposed between the facing planar surfaces of the helically wound segments and between adjacent coils of the helically wound segments, thereby forming a capacitance.
摘要:
Decoupling circuits are provided which transfer energy induced from an MRI pulsed RF field to the housing for an active implantable medical device (AIMD) which serves as an energy dissipating surface. A novel L-C input trap filter is provided which has a dual function. The L-C trap acts as a broadband low pass EMI filter while at the same time also acts as an L-C trap in order to divert induced RF energy from the lead to the housing of the AIMD.
摘要:
A shielded component or network for an active medical device (AMD) implantable lead includes (1) an implantable lead having a length extending from a proximal end to a distal end, all external of an AMD housing, (2) a passive component or network disposed somewhere along the length of the implantable lead, the passive component or network including at least one inductive component having a first inductive value, and (3) an electromagnetic shield substantially surrounding the inductive component or the passive network. The first inductive value of the inductive component is adjusted to a account for a shift in its inductance to a second inductive value when shielded.
摘要:
An RF filter for an active medical device (AMD), for handling RF power induced in an associated lead from an external RF field at a selected MRI frequency or range frequencies includes a capacitor having a capacitance of between 100 and 10,000 picofarads, and a temperature stable dielectric having a dielectric constant of 200 or less and a temperature coefficient of capacitance (TCC) within the range of plus 400 to minus 7112 parts per million per degree centigrade. The capacitor's dielectric loss tangent in ohms is less than five percent of the capacitor's equivalent series resistance (ESR) at the selected MRI RF frequency or range of frequencies.
摘要:
A multilayer helical wave filter having a primary resonance at a selected RF diagnostic or therapeutic frequency or frequency range, includes an elongated conductor forming at least a portion of an implantable medical lead. The elongated conductor includes a first helically wound segment having at least one planar surface, a first end and a second end, which forms a first inductive component, and a second helically wound segment having at least one planar surface, a first end and a second end, which forms a second inductive element. The first and second helically wound segments are wound in the same longitudinal direction and share a common longitudinal axis. Planar surfaces of the helically wound segments face one another, and a dielectric material is disposed between the facing planar surfaces of the helically wound segments and between adjacent coils of the helically wound segments, thereby forming a capacitance.
摘要:
A multilayer helical wave filter having a primary resonance at a selected RF diagnostic or therapeutic frequency or frequency range, includes an elongated conductor forming at least a portion of an implantable medical lead. The elongated conductor includes a first helically wound segment having at least one planar surface, a first end and a second end, which forms a first inductive component, and a second helically wound segment having at least one planar surface, a first end and a second end, which forms a second inductive element. The first and second helically wound segments are wound in the same longitudinal direction and share a common longitudinal axis. Planar surfaces of the helically wound segments face one another, and a dielectric material is disposed between the facing planar surfaces of the helically wound segments and between adjacent coils of the helically wound segments, thereby forming a capacitance.
摘要:
A multilayer helical wave filter having a primary resonance at a selected RF diagnostic or therapeutic frequency or frequency range, includes an elongated conductor forming at least a portion of an implantable medical lead. The elongated conductor includes a first helically wound segment having at least one planar surface, a first end and a second end, which forms a first inductive component, and a second helically wound segment having at least one planar surface, a first end and a second end, which forms a second inductive element. The first and second helically wound segments are wound in the same longitudinal direction and share a common longitudinal axis. Planar surfaces of the helically wound segments face one another, and a dielectric material is disposed between the facing planar surfaces of the helically wound segments and between adjacent coils of the helically wound segments, thereby forming a capacitance.
摘要:
Decoupling circuits are provided which transfer energy induced from an MRI pulsed RF field to the housing for an active implantable medical device (AIMD) which serves as an energy dissipating surface. A novel L-C input trap filter is provided which has a dual function. The L-C trap acts as a broadband low pass EMI filter while at the same time also acts as an L-C trap in order to divert induced RF energy from the lead to the housing of the AIMD.