This disclosure relates, in some examples, to medical leads and medical device systems.
Implantable neurostimulation devices may treat acute or chronic neurological conditions. Deep brain stimulation (DBS), which may include, e.g., the mild electrical stimulation of cortical and/or sub-cortical structures, belongs to this category of implantable devices, and has been shown to be therapeutically effective for such conditions as Parkinson's disease, Dystonia, Epilepsy, Alzheimer's Disease, and Tremor. As another example, DBS may be used to treat psychiatric disorders (obsessive-compulsive disorder, depression). DBS systems generally include one or more leads connected to an implantable pulse generator.
This disclosure is directed to medical leads including thin films incorporating both the electrodes of the medical leads and the conducting tracks for the medical leads.
In one example, this disclosure is directed to a medical device system for at least one of delivery of electrical stimulation pulses or sensing of physiological signals, the system comprising an elongated carrier; a thin film attached to the elongated carrier, the thin film including a plurality of electrodes, a plurality of electrical contacts, and a plurality of conducting tracks, each of the plurality of conducting tracks providing an electrical connection between at least one of the plurality of electrodes and one of the plurality of electrical contacts; and a frame element including a fixation zone for the plurality of electrical contacts of the thin film.
In another example, this disclosure is directed to a method of manufacturing a medical lead, the method comprising assembling a thin film to an elongated carrier, the thin film including a plurality of electrodes, a plurality of electrical contacts, and a plurality of conducting tracks, each of the plurality of conducting tracks providing an electrical connection between at least one of the plurality of electrodes and one of the plurality of electrical contacts, and fixing the plurality of electrical contacts of the thin film on a fixation zone of a frame element.
In another example, an implantable medical device including a first substantially sealed housing; an active lead can including a second substantially sealed housing operatively coupled to the implantable medical device; and a medical lead extending from the active lead can and operatively coupled to the active lead can. The medical lead includes an elongated carrier; a thin film attached to the elongated carrier, the thin film including a plurality of electrodes, a plurality of electrical contacts, and a plurality of conducting tracks, each of the plurality of conducting tracks providing an electrical connection between at least one of the plurality of electrodes and one of the plurality of electrical contacts; and a frame element including a fixation zone for the plurality of electrical contacts of the thin film.
The details of one or more examples of this disclosure may be set forth in the accompanying drawings and the description below. Other features, objects, and advantages of this disclosure may be apparent from the description and drawings, and from the claims.
This disclosure includes techniques for electrically and mechanically connecting a probe including electrodes and other components of a medical system configured to deliver therapy and/or provide sensing via the electrodes. For neural stimulation electrode arrays positioned inside the brain, a probe may include a flexible tube or other elongated carrier supporting a thin film containing electrodes and conducting tracks wrapped around the elongated carrier. Examples of this disclosure may be applied to, for example, leads for deep brain stimulation, cochlear implants, hearing aids, pacemakers, implantable cardiac defibrillators, and other implantable systems including stimulation and/or sensing leads connected to a control box.
In a further example, a medical lead may connect to an active lead can (ALC) mounted to a frame element. The lead may be coupled to electronics to transmit electrical stimulation current via selected electrodes. At least a part of the electronics of the lead may be arranged in the ALC, which may be a box-like structure. The active lead may be coupled to a proximal end of the lead, which, in turn, may be coupled via a lead extension to an implantable pulse generator (IPG). A mounting of the ALC to the frame element may provide option for improved connection of the electronics to the thin film, which may be supported and fixed on the frame element.
The ALC may contain at least a part of the electronics of the medical lead, with at least some of the electronics being connected to the thin film in the area of the fixation zone. In particular, the ALC may be hermetically or substantially hermetically sealed and may include connections to address the plurality of electrodes on the distal end of the thin film, which is arranged at the distal end and may be next to a distal tip of the lead. The plurality of electrodes may comprise any number of electrodes, and in one example contains approximately 40 electrodes. The electrodes may be arranged such that the electrodes are evenly distributed all over the distal end of the lead.
In the example shown in
DBS may be used to treat or manage various patient conditions, such as, but not limited to, seizure disorders (e.g., epilepsy), pain, migraine headaches, psychiatric disorders (e.g., major depressive disorder (MDD), bipolar disorder, anxiety disorders, post-traumatic stress disorder, dysthymic disorder, and obsessive-compulsive disorder (OCD), behavior disorders, mood disorders, memory disorders, mentation disorders, movement disorders (e.g., essential tremor or Parkinson's disease), Huntington's disease, Alzheimer's disease, or other neurological or psychiatric disorders and impairment of patient 12.
DBS leads may implement monopolar, bipolar, or even tripolar stimulation. Neurostimulator devices with steering brain stimulation capabilities may have a large number M of electrode contacts, such as M>10, M>20 and/or M=40, that may be connected to electrical circuits such as current sources and/or (system) ground. Even more electrodes may be provided in some examples. Stimulation may be considered monopolar when the distance between the anode and cathode is several times larger than the distance of the cathode to the stimulation target. During monopolar stimulation in homogeneous tissue, the electric field may be distributed roughly spherically similar to the field from a point source. When the anode is located close to the cathode, creating a bipolar electrode combination, the distribution of the field becomes more directed in the anode-cathode direction. As a result, the field gets stronger and neurons may be more likely to be activated in this area due to a higher field gradient.
Polarization (de- and/or hyperpolarization) of neural tissue may play a prominent role for both suppression of clinical symptoms, as well as induction of stimulation-induced side effects. In order to activate a neuron, the neuron has to be depolarized. Neurons may be depolarized more easily close to the cathode than by the anode (about 3-7 times more depending on type of neuron, etc.).
As illustrated, neurostimulation system 100 includes DBS probe 130 for brain applications with stimulation and/or recording electrodes 132, which may include, more than ten, more than twenty, or, for example, forty electrodes 132 provided on an outer body surface at the distal end of DBS probe 130. However, the techniques described in this disclosure are not so limited. As referred to herein, the distal end of a medical lead or probe may be the remote end of the lead with regard to the body surface area. In particular, in case of a lead for brain application, the distal end of the lead is the lower end of the lead, that is inserted deeper into the brain tissues, and which is remote to the burr-hole of the skull, through which the lead is implanted.
IPG 110 may include more than one implantable pulse generator for delivery of neurostimulation via electrodes 132, and/or one or more sensors configured to sense electrical fields within the brain of the patient, such as electrical fields representing a patient's brain activity and/or electrical fields created by delivery of DBS therapy. In examples in which IPG 110 includes both an implantable pulse generator and one or more sensors, in various examples, either the same set of electrodes or different sets of electrodes may be used for sensing as those used for delivery of DBS therapy.
In the example shown in
Implanted lead extension 120 is coupled at one end to IPG 110 via connector block 30 (also referred to as a header), which may include, for example, electrical contacts that electrically couple to respective electrical contacts on lead extension 120. In turn, conductors of lead extension 120 are electrically coupled to the proximal end of lead 220, as set forth above. Lead 220 extends to, and comprises, the ALC 111. ALC 111 includes electronic module 500 with an active switch matrix to direct stimulation from IPG 110 to any combination of electrodes 132. Likewise, the active switch matrix electronic module 500 can direct sensing signals from any combination of electrodes 132 to IPG 110. In some examples, ALC 111 may digitize sensing signals prior to sending them to IPG 110. IPG 110 may store the sensing signals or a subset of the sensing signals, analyze the sensing signals or a subset of the sensing signals, and/or forward the sensing signals or a subset of the sensing signals to an external device via a wireless transmission.
Lead extension 120 traverses from the implant site of IPG 110, along the neck of patient 12. The distal end of lead extension 120 may connect to a proximal end of lead 220,e e.g., somewhere along the cranium of patient 12. The lead extends to ALC 111 to access brain 28. IPG 110 and ALC 111 can be constructed of biocompatible materials that resist corrosion and degradation from bodily fluids. IPG 110 may comprise a hermetic outer housing 34 to substantially enclose components, such as a processor, a therapy module, and memory. Likewise, ALC 111 may comprise a hermetic outer housing to substantially enclose electronic components.
In the example shown in
During implantation of probe 130 within patient 12, a clinician may attempt to position electrodes 132 of probe 130 such that electrodes 132 are able to deliver electrical stimulation to one or more target tissue sites within brain 28 to manage patient symptoms associated with a disorder of patient 12. Probe 130 may be placed at any location within brain 28 such that electrodes 132 are capable of providing electrical stimulation to target therapy delivery sites within brain 28 during treatment.
The anatomical region within patient 12 that serves as the target tissue site for stimulation delivered by system 100 may be selected based on the patient condition. Different neurological or psychiatric disorders may be associated with activity in one or more of regions of brain 28, which may differ between patients. Accordingly, the target therapy delivery site for electrical stimulation therapy delivered by probe 130 may be selected based on the patient condition. For example, a suitable target therapy delivery site within brain 28 for controlling a movement disorder of patient 12 may include one or more of the pedunculopontine nucleus (PPN), thalamus, basal ganglia structures (e.g., globus pallidus, substantia nigra or subthalamic nucleus), zona inserta, fiber tracts, lenticular fasciculus (and branches thereof), ansa lenticularis, or the Field of Forel (thalamic fasciculus). The PPN may also be referred to as the pedunculopontine tegmental nucleus.
As another example, in the case of MDD, bipolar disorder, OCD, or other anxiety disorders, probe 130 may be implanted to deliver electrical stimulation to the anterior limb of the internal capsule of brain 28, and only the ventral portion of the anterior limb of the internal capsule (also referred to as a VC/VS), the subgenual component of the cingulate cortex (which may be referred to as CG25), anterior cingulate cortex Brodmann areas 32 and 24, various parts of the prefrontal cortex, including the dorsal lateral and medial pre-frontal cortex (PFC) (e.g., Brodmann area 9), ventromedial prefrontal cortex (e.g., Brodmann area 10), the lateral and medial orbitofrontal cortex (e.g., Brodmann area 11), the medial or nucleus accumbens, thalamus, intralaminar thalamic nuclei, amygdala, hippocampus, the lateral hypothalamus, the Locus ceruleus, the dorsal raphe nucleus, ventral tegmentum, the substantia nigra, subthalamic nucleus, the inferior thalamic peduncle, the dorsal medial nucleus of the thalamus, the habenula, the bed nucleus of the stria terminalis, or any combination thereof.
As another example, in the case of a seizure disorder or Alzheimer's disease, for example, probe 130 may be implanted to deliver electrical stimulation to regions within the Circuit of Papez, such as, for example, one or more of the anterior thalamic nucleus, the internal capsule, the cingulate, the fornix, the mammillary bodies, the mammillothalamic tract (mammillothalamic fasciculus), or the hippocampus. Target therapy delivery sites not located in brain 28 of patient 12 are also contemplated.
The techniques of this disclosure may be implemented in combination with systems including smaller electrodes, such as electrodes manufactured using thin film manufacturing. Examples of such manufacturing techniques for a medical lead made from a thin film based on thin film technology are disclosed in United States Patent Application Publication No. 2011/0224765, titled, “SPIRALED WIRES IN A DEEP-BRAIN STIMULATION PROBE,” the entire contents of which are incorporated by reference herein. The thin film medical leads may be fixed on an elongated carrier to form a medical lead. These medical leads may include multiple electrode areas and may enhance the precision to address the appropriate target in the brain and relax the specification of positioning. Meanwhile, undesired side effects due to undesired stimulation of neighboring areas may be limited.
Although lead 220 and lead extension 120 are shown in
In the example shown in
In some examples, outer housing 34 of IPG 110 and/or the housing of ALC 111 may include one or more stimulation and/or sensing electrodes. For example, housing 34 can comprise an electrically conductive material that is exposed to tissue of patient 12 when IPG 110 is implanted in patient 12, or an electrode can be attached to housing 34.
IPG 110 and ALC 111 may deliver electrical stimulation therapy to brain 28 of patient 12 according to one or more therapy programs. A therapy program may define one or more electrical stimulation parameter values for therapy generated by a stimulation generator of IPG 110 and delivered from IPG 110 to a target therapy delivery site within patient 12 via one or more electrodes 132. The electrical stimulation parameters may define an aspect of the electrical stimulation therapy, and may include, for example, voltage or current amplitude of an electrical stimulation signal, a frequency of the electrical stimulation signal, and, in the case of electrical stimulation pulses, a pulse rate, a pulse width, a waveform shape, and other appropriate parameters such as duration or duty cycle. In addition, if different electrodes are available for delivery of stimulation, a therapy parameter of a therapy program may be further characterized by an electrode combination, which may define electrodes 132 selected for delivery of electrical stimulation and their respective polarities. In some examples, as an alternative to stimulation pulses, stimulation may be delivered using a continuous waveform and the stimulation parameters may define this waveform.
In addition to being configured to deliver therapy to manage a disorder of patient 12, therapy system 100 may be configured to sense bioelectrical brain signals of patient 12. For example, IPG 110 may include a sensing module that is configured to sense bioelectrical brain signals within one or more regions of brain 28 via a subset of electrodes 132, another set of electrodes, or both. Accordingly, in some examples, electrodes 132 may be used to deliver electrical stimulation from the therapy module to target sites within brain 28 as well as sense brain signals within brain 28. However, IPG 110 can also use a separate set of sensing electrodes to sense the bioelectrical brain signals. In some examples, the sensing module of IPG 110 may sense bioelectrical brain signals via one or more of the electrodes 132 that are also used to deliver electrical stimulation to brain 28. In other examples, one or more of electrodes 132 may be used to sense bioelectrical brain signals while one or more different electrodes of electrodes 132 may be used to deliver electrical stimulation.
Examples of bioelectrical brain signals include, but are not limited to, electrical signals generated from local field potentials (LFPs) within one or more regions of brain 28, such as, but not limited to, an electroencephalogram (EEG) signal or an electrocorticogram (ECoG) signal. In some examples, the electrical signals within brain 28 may reflect changes in electrical current produced by the sum of electrical potential differences across brain tissue.
External medical device programmer 14 is configured to wirelessly communicate with IPG 110 as needed to provide or retrieve therapy information. Programmer 14 is an external computing device that the user, for example, the clinician and/or patient 12, may use to communicate with IPG 110. For example, programmer 14 may be a clinician programmer that the clinician uses to communicate with IPG 110 and program one or more therapy programs for IPG 110. In addition, or instead, programmer 14 may be a patient programmer that allows patient 12 to select programs and/or view and modify therapy parameter values. The clinician programmer may include more programming features than the patient programmer. In other words, more complex or sensitive tasks may only be allowed by the clinician programmer to prevent an untrained patient from making undesired changes to IPG 110.
Programmer 14 may be a hand-held computing device with a display viewable by the user and an interface for providing input to programmer 14 (i.e., a user input mechanism). For example, programmer 14 may include a small display screen (e.g., a liquid crystal display (LCD) or a light emitting diode (LED) display) that presents information to the user. In addition, programmer 14 may include a touch screen display, keypad, buttons, a peripheral pointing device or another input mechanism that allows the user to navigate through the user interface of programmer 14 and provide input. If programmer 14 includes buttons and a keypad, then the buttons may be dedicated to performing a certain function, for example, a power button, the buttons and the keypad may be soft keys that change in function depending upon the section of the user interface currently viewed by the user, or any combination thereof.
In other examples, programmer 14 may be a larger workstation or a separate application within another multi-function device, rather than a dedicated computing device. For example, the multi-function device may be a notebook computer, tablet computer, workstation, cellular phone, personal digital assistant or another computing device that may run an application that enables the computing device to operate as a secure medical device programmer 14. A wireless adapter coupled to the computing device may enable secure communication between the computing device and IPG 110.
When programmer 14 is configured for use by the clinician, programmer 14 may be used to transmit programming information to IPG 110. Programming information may include, for example, hardware information, such as the type of ALC 111, the type of probe 130, the arrangement of electrodes 132 on probe 130, the position of probe 130 within brain 28, one or more therapy programs defining therapy parameter values, and any other information that may be useful for programming into IPG 110. Programmer 14 may also be capable of completing functional tests (e.g., measuring the impedance of electrodes 132 of probe 130).
With the aid of programmer 14 or another computing device, a clinician may select one or more therapy programs for therapy system 100 and, in some examples, store the therapy programs within IPG 110. Programmer 14 may assist the clinician in the creation/identification of therapy programs by providing physiologically relevant information specific to patient 12.
Programmer 14 may also be configured for use by patient 12. When configured as a patient programmer, programmer 14 may have limited functionality (compared to a clinician programmer) in order to prevent patient 12 from altering critical functions of IPG 110 or applications that may be detrimental to patient 12.
Whether programmer 14 is configured for clinician or patient use, programmer 14 is configured to communicate with IPG 110 and, optionally, another computing device, via wireless communication. Programmer 14, for example, may communicate via wireless communication with IPG 110 using radio frequency (RF) telemetry techniques known in the art. Programmer 14 may also communicate with another programmer or computing device via a wired or wireless connection using any of a variety of local wireless communication techniques, such as RF communication according to the 802.11 or BLUETOOTH® specification sets, infrared (IR) communication according to the IRDA specification set, or other standard or proprietary telemetry protocols. Programmer 14 may also communicate with other programming or computing devices via exchange of removable media, such as magnetic or optical disks, memory cards or memory sticks. Further, programmer 14 may communicate with IPG 110 and another programmer via remote telemetry techniques known in the art, communicating via a local area network (LAN), wide area network (WAN), public switched telephone network (PSTN), or cellular telephone network, for example.
Therapy system 100 may be implemented to provide chronic stimulation therapy to patient 12 over the course of several months or years. However, system 100 may also be employed on a trial basis to evaluate therapy before committing to full implantation. If implemented temporarily, some components of system 100 may not be implanted within patient 12. For example, patient 12 may be fitted with an external medical device, such as a trial stimulator, rather than IPG 110. The external medical device may be coupled to percutaneous medical leads or to implanted medical leads via a percutaneous extension. If the trial stimulator indicates DBS system 100 provides effective treatment to patient 12, the clinician may implant a chronic stimulator within patient 12 for relatively long-term treatment.
In the example shown in
Stimulation generator 64, under the control of processor 60, generates stimulation signals for delivery to patient 12 via selected combinations of electrodes 132. In some examples, stimulation generator 64 generates and delivers stimulation signals to one or more target regions of brain 28 (
The processors described in this disclosure, including processor 60 and processor 504, may include one or more digital signal processors (DSPs), general-purpose microprocessors, application specific integrated circuits (ASICs), field programmable logic arrays (FPGAs), or other equivalent integrated or discrete logic circuitry, or combinations thereof. The functions attributed to processors described herein may be provided by a hardware device and embodied as software, firmware, hardware, or any combination thereof. Processor 60 is configured to control stimulation generator 64 according to therapy programs 74 stored by memory 62 to apply particular stimulation parameter values specified by one or more therapy programs.
Processor 60 may control switch module 68 to select stimulation generator 64 or sensing module 66. In turn, processor 60 directs processor 504 of electronic module 500 to apply the stimulation signals generated by stimulation generator 64 to selected combinations of electrodes 132, or to sense signals from selected combinations of electrodes 132 via sense amplifier 506 of electronic module 500. In particular, active switch matrix 502 of electronic module 500 may couple stimulation signals to selected conducting tracks within probe 130, which, in turn, deliver the stimulation signals to selected electrodes 132. Hence, although there may be many, for example, 40, electrodes, active switch matrix 502 may select a subset of one, two or more electrodes for delivery of stimulation pulses. Active switch matrix 502 may be a switch array, an array of one or more transistors such as Field-Effect Transistors (FETs) switch matrix, multiplexer, and/or demultiplexer, or any other type of switching module configured to selectively couple stimulation energy to selected electrodes 132 and to selectively sense bioelectrical brain signals with selected electrodes 132. Hence, stimulation generator 64 is coupled to electrodes 132 via switch module 68, conductors between IPG 110 and ALC 111, active switch matrix 502, and conducting tracks within probe 130. Additionally, the logic path between stimulation generator and electrodes 132 may include one or more discrete components such as capacitors, resistors, logic gates, transistors, and the like. Thus, it will be understood that when reference is made to coupling of stimulation generator 64 or other components of IPG 110 to electrodes 132, this refers to the enabling of a logic path between the logic components so that signals may be transferred there between, and is not intended to necessarily require a direct electrical coupling of the components.
In some examples, however, IPG 110 does not include switch module 68 and all switching functions may be performed by active switch matrix 502. For example, IPG 110 may include multiple sources of stimulation energy (e.g., current sources). Stimulation generator 64 may be a single channel or multi-channel stimulation generator. In particular, stimulation generator 64 may be capable of delivering a single stimulation pulse, multiple stimulation pulses or continuous signal at a given time via a single electrode combination or multiple stimulation pulses at a given time via multiple electrode combinations. In some examples, however, stimulation generator 64 and active switch matrix 502 may be configured to deliver multiple channels on a time-interleaved basis. For example, active switch matrix 502 may serve to time divide the output of stimulation generator 64 across different electrode combinations at different times to deliver multiple programs or channels of stimulation energy to patient 12.
In addition to, or instead of stimulation generator 64 of IPG, a stimulation generator may reside within ALC (not shown) and may generate the stimulation pulses that are routed to electrodes 132 via active switch matrix 502. In such cases, the stimulation generator within the ALC may receive power from power source 72 and may receive control signals from stimulation generator 64 or other logic of IPG 110. The stimulation generator in ALC may be provided in addition to, or instead of, stimulation generator 64 of IPG 110. Thus, electronics for driving probe 130 and electrodes 132 of lead may reside in IPG 110, ALC 111, or some combination thereof. As is the case with any stimulation generator 64 of IPG, any stimulation of ALC may be a single channel or multi-channel stimulation generator as set forth above.
Sensing module 66, under the control of processor 60, is configured to sense bioelectrical brain signals of patient 12 via active switch matrix 502, sense amplifier 506, and a selected subset of electrodes 132 or with one or more electrodes 132 and at least a portion of a conductive outer housing 34 of IPG 110, at least a portion of a conductive outer housing of ALC 111, an electrode on outer housing 34 of IPG 110, an electrode on an outer housing of ALC 111, or another reference. Processors 60 and 504 may control switch module 68 and active switch matrix 502 to electrically connect sensing module 66 to selected electrodes 132 via active switch matrix 502 and sense amplifier 506 of ALC 111. In this way, sensing module 66 may selectively sense bioelectrical brain signals with different combinations of electrodes 132.
Telemetry module 70 is configured to support wireless communication between IPG 110 and an external programmer 14 or another computing device under the control of processor 60. Processor 60 of IPG 110 may receive, as updates to programs, values for various stimulation parameters from programmer 14 via telemetry module 70. The updates to the therapy programs may be stored within therapy programs 74 portion of memory 62. Telemetry module 70 in IPG 110, as well as telemetry modules in other devices and systems described herein, such as programmer 14, may accomplish communication by RF communication techniques. In addition, telemetry module 70 may communicate with external medical device programmer 14 via proximal inductive interaction of IPG 110 with programmer 14. Accordingly, telemetry module 70 may send and receive information to/from external programmer 14 on a continuous basis, at periodic intervals, or upon request from IPG 110 or programmer 14.
Power source 72 delivers operating power to various components of IPG 110. Power source 72 may include a small rechargeable or non-rechargeable battery and a power generation circuit to produce the operating power. Recharging may be accomplished through proximal inductive interaction between an external charger and an inductive charging coil within IPG 110. In some examples, power requirements may be small enough to allow IPG 110 to utilize patient motion and implement a kinetic energy-scavenging device to trickle charge a rechargeable battery. In other examples, traditional batteries may be used for a limited period of time.
In the illustration of
In the example configuration of
As described above, ALC 111 includes a N-pin connector 510, which is configured to be coupled to respective conductive paths of proximal end of lead 220. ALC may also include a M-pin connector 520 (e.g., M=40) for DBS probe 130, e.g., for electrically coupling respective electrodes 132 to electronic module 500. As shown in
DBS probe 130 comprises an elongated carrier 302 for thin film 301, where elongated carrier 302 provides the mechanical configuration of DBS probe 130 and thin film 301. Elongated carrier 302 may be a flexible carrier, such as a flexible tubing. In some examples, elongated carrier 302 may be formed from a silicon tubing.
Elongated carrier 302 may have any suitable configuration. In some examples, elongated carrier 302 may be an elongated member having a circular cross-section, although other cross-sections are contemplated, such as, e.g., square or hexagonal. Elongated carrier 302 may be a solid member or have a hollow core. In some examples, it is preferred that elongated carrier 302 be relatively stiff during implantation but able to flex or bend to some degree after implantation. The hollow core may allow for the insertion of a stiffening member such as a stylet into the hollow core, e.g., during implantation of lead 300. Elongated carrier 302 may be configured to not substantially shrink, stretch, or compress during and/or after implantation.
In some examples, elongated carrier 302 should be flexible and have a good rotational torque transfer, e.g., in instances of permanent (chronic) implant of lead 300. Some acute applications may have a different set of preferences. For instance, in acute implantation, no burr-hole devise may be used and flexibility and limited compressibility are of less concern.
Elongated carrier 302 may be formed of any suitable material including silicone, titanium, and/or polyether ether ketone (PEEK) based materials. For the mechanical requirements as mentioned above, other polymers can be more useful e.g. bionate. In addition, metal tubes (e.g., laser machined to bendable chains) may be used. In acute applications, a solid metal may be used for elongated carrier 302. In acute application, there may not be a need for elongated carrier 302 to be hollow or flexible. In chronic applications, elongated carrier 302 is implanted with a stiffener inside. After implantation, the stiffener may be removed.
Distal portion of lead 300 may have a diameter between about 0.5 millimeters (mm) and about 3 mm diameter, e.g., about 1.3 mm. The diameter of lead 300 may be defined by the diameter of carrier core 302 in combination with the thickness of thin film 301 and any coating applied over carrier core 302 and/or thin film 301. The proximal portion of lead 300 (the portion adjacent to ALC 111) may have a diameter between about 0.5 mm and about 4mm diameter. The length of lead 300 may be about 10 centimeters (cm) to about 20 cm, e.g., about 15 cm, and may vary based on the particular application, e.g., acute versus chronic implantation. Other dimensions than those examples described herein are contemplated.
Thin film 301 may include at least one electrically conductive layer, such as one made of a biocompatible material. Thin film 301 may be formed by a thin film product having a distal end 304, a cable 303 with conducting tracks and a proximal end 310, as illustrated in
Thin film structures may provide an advantage that small structures may be built of with this technology. A thin film is a layer or multilayer structure of material ranging from fractions of a nanometer (monolayer) to several micrometers in thickness. Electronic semiconductor devices and optical coatings may be the main applications benefiting from thin-film construction. Thin film technology and thin film manufacturing processes may allow the manufacturing of leads for medical purposes such as neurostimulation leads like, for example, DBS leads with diameters of less than 2 mm, for example 0.75 mm to 1.50 mm and a plurality of electrodes, such as 40 electrodes, although any number of electrodes may be used, including more than 40 electrodes. In addition, thin film technology allows for various configurations of high density electrode arrangements, including, for example, a series of small ring electrodes or an arrangement of electrodes with more complex geometries. During stimulation or sensing, different combinations of electrodes may be used to precisely direct the stimulation or sensing within a patient.
As illustrated in
As illustrated in
In other examples, a DBS lead may include, for example, four 1.5 millimeters wide cylindrical electrodes, at the distal end spaced by between about 0.5 millimeters and 1.5 millimeters. In this example, a diameter of the medical lead may be about 1.27 millimeters and the metal used for the electrodes and the interconnect wires may be an alloy of platinum and iridium. The coiled interconnect wires may be insulated individually by fluoropolymer coating and protected in an 80 micron urethane tubing. With such an electrode design, the current distribution may emanate uniformly around the circumference of the electrode, which medical leads to stimulation of all areas surrounding the electrode.
As compared to probe 130, such a design may limit fine spatial control over stimulation field distributions. The lack of fine spatial control over field distributions implies that stimulation easily spreads into adjacent structures inducing adverse side effects in about thirty percent of the patients. To overcome this problem, medical leads with high-density electrode arrangements, such as those examples illustrated herein, facilitate electrical field position adjustments in smaller increments, hence providing the ability to steer the stimulation field to the appropriate target.
The clinical benefit of DBS may be largely dependent on the spatial distribution of the stimulation field in relation to brain anatomy. To improve efficacy and efficiency of DBS while avoiding unwanted side effects, precise control over the stimulation field is important. Electrodes 132 of probe 130, with high-density electrode arrangements, provide much greater adjustability and precision than a medical lead with cylindrical electrodes.
Thin film structures used to form the leads with high-density electrode arrangements may be relatively fragile, and the handling of the leads may be difficult. Also, the connection of the thin film with the electronics of the overall system is important, as this connection should be mechanically strong and electrically reliable. Due to the mechanical properties of the thin film, this connection forms an ambitious challenge. It is therefore an object of the present disclosure to provide a medical lead system and a method of manufacturing a medical lead system, especially in that the fixation of thin film 301, e.g., to ALC 11, can be made mechanically strong and electrically reliable.
Connecting thin film 301 at proximal end 310 of probe 130 to ALC 111 requires forming electrical connections between proximal contacts 305 corresponding to one or more conductive tracks defined by thin film 301 and electrical connector 520 of ALC 111 as well as providing a durable mechanical connection between probe 130 and ALC 111 to facilitate a reliable electrical and mechanical connection. In some examples, probe 130 may be electrically and mechanically connected to ALC 111 by way of a landing block that may be used to make a reliable connection. The “landing block,” a thin metal frame, provides both a mechanical fixation of the flexible tube as well as an electrical connection to ALC 111.
As shown in
Proximal end 310 of thin film 301 is mechanically connected to ALC 111 by way of frame element 320. Frame element 320 provides fixation zone 322 for proximal end 310 of thin film 301. Proximal end 310 carries interconnect contacts 305 (not shown in
The fixation between fixation zone 322 and proximal end 310 of thin film 301 is established, for example, by gluing using an adhesive or other suitable options. By this, the fixation of a thin film 301 can be made mechanically strong and electrically reliable as the fixation is done within a zone and thus over a certain area and not by, for example, multiple dot-like connections. Removable tab 311 may be used to provide tension on thin film 301 during the winding of the thin film 301 around the carrier 302 and/or during the fixation of proximal end 310 on fixation zone 322 of frame element 320. Following the fixation of proximal end 310 on fixation zone 322 of frame element 320, removable tab 311 may be removed. Frame element 320 may be formed from a metal plate and may have and suitable dimensions, e.g., a thickness between 0.1 mm to 1 mm. This aspect allows an improved forming of the frame element and a good stability and support for thin film 301.
Frame element 320 has two mounting portions 330, 332, wherein first mounting portion 330 is mounted to elongated carrier 302 and second mounting portion 332 is also mounted to elongated carrier 302, after frame element 320 is partially slid along the axis X (labelled in
In addition, post 333 may add stability to elongated carrier 302 adjacent mounting portions 330, 332 and proximal end 310 of thin film 301. For example, elongated carrier 302 may be a flexible tube, such as a silicon tube. Post 333 may run within a hollow center of carrier 302 to stiffen a portion of elongated carrier 302 and facilitate securing frame element 320 to elongated carrier 302 by clamping mounting portions 330, 332 on the proximal end of elongated carrier 302, thereby pinching the flexible tubing between post 333 and mounting portions 330, 332. In addition, post 333 may extend past the proximal end 310 of thin film 301 to provide dimensional stability to elongated carrier 302 adjacent frame element 320 and proximal end 310 of thin film 301. This may protect thin film 301 from bending adjacent to adjacent frame element 320
Mounting portions 330, 332 may include at least one mounting tube portion or at least one mounting tube segment portion, which is at least partially extends around elongated carrier 302. Mounting portions 330, 332 may be formed from a plate portion of frame element 301. In other examples, mounting portions 330, 332 may be replaced with a plurality of mounting fingers, which are at least partially extended around the flexible tube. The mounting fingers may allow a lightweight and stable connection. Also, in case that the mounting finger shall be fixated to the underlying flexible tube by glue, such a connection may be provided with a consistent and homogenous glue portion.
As best seen in
As shown in
Each electrical contact 306 of portion 338 of interposer 334 is electrically coupled through a respective conductive trace 307 (or path) to a respective individual electrical contact 308 of portion 336. The electrical contacts 308 of portion 336 may couple to an individual contact of connector 520 of ALC 111. For example, the arrangement of electrical contacts 308 of interposer may be substantially the same as the arrangement of contacts (not shown) of connector 520 of ALC. When properly aligned the first connection portion 336 may be placed over electrical connector 520 to electrically couple the contacts 308 of interposer 334 with the contacts of connector 520. The electrical contacts of portion 336 may have a different pitch, size and/or other configuration in one embodiment than those of electrical contacts of portion 338. Each electrical contact may be attached another contact using any suitable technique, such as, e.g., a conductive polymer adhesive.
In this manner, interposer 334 may electrically couple the individual contacts 305 at the distal end 310 of thin film 301 to individual contacts of connector 520 of ALC 11. In such a configuration, the individual electrodes 132 at the distal end 304 of thin film 301 may be electrically coupled to ALC 111. When electrically coupled in such manner, electrical signals may be conducted from ALC 11 to electrodes 132, e.g., to delivery electrical stimulation and/or sense electrical signals.
Interposer connector 334 may improve the stability and reliability of the connection between connectors 520 of ALC 111 and contacts 305 of thin film 301. For example, connectors 520 of ALC 111, such as, e.g., in the form of feedthroughs, may be larger than contacts 305 of thin film 301. With interposer connector 334, no large area is required to realize the interconnection between interconnect contacts 305 of thin film 301 and the relatively large connectors 520 of ALC 111.
Although not shown, in an alternative to the example shown in
As shown in
A user, such as a clinician or patient 12, may interact with programmer 414 through user interface 486. User interface 486 includes a display (not shown), such as a LCD or LED display or other type of screen, with which processor 480 may present information related to the therapy (e.g., therapy programs). In addition, user interface 486 may include an input mechanism to receive input from the user. The input mechanisms may include, for example, any one or more of buttons, a keypad (e.g., an alphanumeric keypad), a peripheral pointing device, a touch screen, or another input mechanism that allows the user to navigate through user interfaces presented by processor 480 of programmer 414 and provide input. In other examples, user interface 486 also includes audio circuitry for providing audible notifications, instructions or other sounds to patient 12, receiving voice commands from patient 12, or both.
Memory 482 may include instructions for operating user interface 486 and telemetry module 484, and for managing power source 488. Processor 480 may store the therapy programs and in memory 482 as stored therapy programs 494 and store the sensing parameters and the recorded results of the sensing as stored sensing programs 492. A clinician may review the stored therapy programs 494 and stored sensing programs 492 (e.g., during programming of IPG 110) to select one or more therapy programs with which IPG 110 may deliver efficacious electrical stimulation to patient 12. For example, the clinician may interact with user interface 486 to retrieve the stored therapy programs 494 and stored sensing programs 492.
In some examples, processor 480 is configured to generate and present, via a display of user interface 486, a graphical user interface (GUI) that presents a list of therapy programs. A user (e.g., a clinician) may interact with the GUI to manipulate the list of therapy programs. In some examples, a user may also interact with the graphical user interface to select a particular therapy program, and, in response to receiving the user input, programmer 414 may provide additional details about the therapy program. For example, the additional details presented by programmer 414 may include details about the individual parameter settings of the therapy program, such as the electrical stimulation parameter values, electrode combination, or both.
In some examples, patient 12, a clinician or another user may interact with user interface 486 of programmer 414 in other ways to manually select programs from the stored therapy programs 494 and stored sensing programs 492 for programming IPG 110, generate new therapy and sensing programs, modify stored therapy programs 494 and stored sensing programs 492, transmit the selected, modified, or new programs to IPG 110, or any combination thereof.
Memory 482 may include any volatile or nonvolatile memory, such as RAM, ROM, EEPROM or flash memory. Memory 482 may also include a removable memory portion that may be used to provide memory updates or increases in memory capacities. A removable memory may also allow sensitive patient data to be removed before programmer 414 is used by a different patient.
Wireless telemetry in programmer 414 may be accomplished by RF communication or proximal inductive interaction of external programmer 414 with IPG 110. This wireless communication is possible through the use of telemetry module 484. Accordingly, telemetry module 484 may be similar to the telemetry module contained within IPG 110. In other examples, programmer 414 may be capable of infrared communication or direct communication through a wired connection. In this manner, other external devices may be capable of communicating with programmer 414 without needing to establish a secure wireless connection.
Power source 488 is configured to deliver operating power to the components of programmer 414. Power source 488 may include a battery and a power generation circuit to produce the operating power. In some examples, the battery may be rechargeable to allow extended operation. In other examples, traditional batteries (e.g., nickel cadmium or lithium ion batteries) may be used. In addition, programmer 414 may be directly coupled to an alternating current outlet to operate.
Thin film 301 is attached to elongated carrier 302 (602) to form probe 130 (
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ALC 111 is mounted to frame element 320 (606). For example, ALC 111 may be welded to frame element 320. Then, an electrical connection is formed between the electronics module 500 of ALC 111 and proximal contacts 305 of thin film 301 (608). For example, contacts 306 and 308 of interposer connector 334 may provide for a connection between proximal contacts 305 of thin film 301 and connectors 520 (
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While the techniques described herein are suitable for systems and methods involving DBS therapies, and may be used treat such disorders as Parkinson's disease, Alzheimer's disease, tremor, dystonia, depression, epilepsy, OCD, and other disorders, the techniques are not so limited. One or more such techniques and systems may be applied to treat disorders such as chronic pain disorders, urinary or fecal incontinence, sexual dysfunction, obesity, mood disorders, gastroparesis or diabetes, and may involve other types of stimulation such as spinal cord stimulation, cardiac stimulation, pelvic floor stimulation, sacral nerve stimulation, peripheral nerve stimulation, peripheral nerve field stimulation, gastric stimulation, or any other electrical stimulation therapy. In some cases, the electrical stimulation may be used for muscle stimulation.
In addition, it should be noted that examples of the systems and techniques described herein may not be limited to treatment or monitoring of a human patient. In alternative examples, example systems and techniques may be implemented in non-human patients, e.g., primates, canines, equines, pigs, and felines. These other animals may undergo clinical or research therapies that my benefit from the subject matter of this disclosure.
The techniques of this disclosure may be implemented in a wide variety of computing devices, medical devices, or any combination thereof. Any of the described units, modules or components may be implemented together or separately as discrete but interoperable logic devices. Depiction of different features as modules or units is intended to highlight different functional aspects and does not necessarily imply that such modules or units must be realized by separate hardware or software components. Rather, functionality associated with one or more modules or units may be performed by separate hardware or software components, or integrated within common or separate hardware or software components.
The disclosure contemplates computer-readable storage media comprising instructions to cause a processor to perform any of the functions and techniques described herein. The computer-readable storage media may take the example form of any volatile, non-volatile, magnetic, optical, or electrical media, such as a RAM, ROM, NVRAM, EEPROM, or flash memory that is tangible. The computer-readable storage media may be referred to as non-transitory. A server, client computing device, or any other computing device may also contain a more portable removable memory type to enable easy data transfer or offline data analysis. The techniques described in this disclosure, including those attributed to various modules and various constituent components, may be implemented, at least in part, in hardware, software, firmware or any combination thereof. For example, various aspects of the techniques may be implemented within one or more processors, including one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuitry, as well as any combinations of such components, remote servers, remote client devices, or other devices. The term “processor” or “processing circuitry” may generally refer to any of the foregoing logic circuitry, alone or in combination with other logic circuitry, or any other equivalent circuitry.
Such hardware, software, firmware may be implemented within the same device or within separate devices to support the various operations and functions described in this disclosure. In addition, any of the described units, modules or components may be implemented together or separately as discrete but interoperable logic devices. Depiction of different features as modules or units is intended to highlight different functional aspects and does not necessarily imply that such modules or units must be realized by separate hardware or software components. Rather, functionality associated with one or more modules or units may be performed by separate hardware or software components, or integrated within common or separate hardware or software components.
The techniques described in this disclosure may also be embodied or encoded in an article of manufacture including a computer-readable storage medium encoded with instructions. Instructions embedded or encoded in an article of manufacture including a computer-readable storage medium , may cause one or more programmable processors, or other processors, to implement one or more of the techniques described herein, such as when instructions included or encoded in the computer-readable storage medium are executed by the one or more processors. Example computer-readable storage media may include random access memory (RAM), read only memory (ROM), programmable read only memory (PROM), erasable programmable read only memory (EPROM), electronically erasable programmable read only memory (EEPROM), flash memory, a hard disk, a compact disc ROM (CD-ROM), a floppy disk, a cassette, magnetic media, optical media, or any other computer readable storage devices or tangible computer readable media. The computer-readable storage medium may also be referred to as storage devices.
In some examples, a computer-readable storage medium comprises non-transitory medium. The term “non-transitory” may indicate that the storage medium is not embodied in a carrier wave or a propagated signal. In certain examples, a non-transitory storage medium may store data that can, over time, change (e.g., in RAM or cache).
Various examples have been described herein. Any combination of the described operations or functions is contemplated. These and other examples are within the scope of the following claims.
This application claims the benefit of U.S. Provisional Application Serial No. 62/084,378, by Weekamp et al., and filed Nov. 25, 2014, which is incorporated herein by reference in its entirety.
Number | Date | Country | |
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62084378 | Nov 2014 | US |