Patent Description:
Chemotherapy is an important therapy for destroying cancers, however during therapy hematopoietic cells are damaged as well. Different types of treatment have been developed for chemotherapy-induced cytopenia, including erythropoietin for anemia, Granulocyte Colony Stimulating Factor (G-CSF) for neutropenia, and thrombopoietin for thrombocytopenia. However, these hematologic toxicities cannot be fully reversed by the administration of these growth factors. As the result, bleeding and infection are still the major causes of treatment-related morbidity and mortality in patients with cancers. Moreover, these adverse effects can be aggravated further over multiple chemotherapy cycles, which impedes hematopoietic stem cell (HSCs) mobilization, harvest, and engraftment after transplantation.

It should also be appreciated that not only are hematopoietic and stromal cells affected, the sympathetic nerve system (SNS) within the bone marrow microenvironment is also damaged by several chemotherapeutic agents. Injury of bone marrow SNS impairs the regeneration of HSCs and the recovery of bone marrow niche after genotoxic insult.

The SNS plays a critical role in maintaining the bone marrow niche and modulating hematopoiesis. Various types of adrenergic receptors (ARs) are involved in this phenomenon. After stimulation of β2-ARs on hematopoietic progenitor cells and β3-ARs on Nestin+-mesenchymal stem cells (MSCs), HSCs can proliferate and egress into peripheral blood. Activation of α2-ARs promotes megakaryocyte adhesion, migration, and proplatelet formation. Sympathetic denervation of a murine hind limb using surgical transection of femoral and sciatic nerves leads to premature HSC aging, and supplementation of a sympathomimetic drug acting on ARs significantly rejuvenated in vivo function of HSCs. However, this pharmaceutical approach raises concerns about concomitant systemic adverse effects, such as hypertension, tachycardia, and atherosclerosis, inevitably limiting its clinical applicability.

Accordingly, a need exists for enhanced chemotherapy treatment options which mitigate adverse events. The present disclosure describes a treatment option which overcomes many of the adverse events, while providing additional benefits.

<CIT> discloses methods, devices, and systems for in vivo treatment of cell proliferative disorders. The invention can be used to treat solid tumors, such as brain tumors. The methods rely on non-thermal irreversible electroporation (IRE) or supra-poration to cause cell death in treated tumors. In embodiments, the methods comprise the integration of ultra-short electric pulses, both temporally and spatially, to achieve the desired modality of cell death.

<CIT> discloses transcutaneous electrical nerve stimulation devices and magnetic stimulation devices, along with methods of treating medical disorders using energy that is delivered noninvasively by such devices. The disorders comprise migraine and other primary headaches such as cluster headaches, including nasal or paranasal sinus symptoms that resemble an immune-mediated response ("sinus" headaches). The devices and methods may also be used to treat rhinitis, sinusitis, or rhinosinusitis, irrespective of whether those disorders are co-morbid with a headache. They may also be used to treat other disorders that may be co-morbid with migraine or cluster headaches, such as anxiety disorders. In preferred embodiments of the disclosed methods, one or both of the patient's vagus nerves are stimulated non-invasively. In other embodiments, parts of the sympathetic nervous system and/or the adrenal glands are stimulated.

<CIT> discloses methods and devices for activating brown adipose tissue (BAT). Generally, the methods and devices can activate BAT to increase thermogenesis, e.g., increase heat production in the patient, which over time can lead to weight loss. In one embodiment, a medical device is provided that activates BAT by electrically stimulating nerves that activate the BAT and/or electrically stimulating brown adipocytes directly, thereby increasing thermogenesis in the BAT and inducing weight loss through energy expenditure.

<CIT> discloses a method including chronically implanting a nerve cuff electrode on a portion of a hypoglossal nerve, chronically implanting a respiration sensing lead subcutaneously in a thorax of a patient, the respiration sensing lead having a plurality of bio-impedance electrodes defining at least one bio-impedance vector. The method may also include sensing a bio-impedance signal corresponding to respiration via a bio-impedance vector on an anterior side of the thorax, analyzing the bio-impedance signal to identify onsets of expiration, predicting an onset of a future expiratory phase, and delivering a stimulus to the portion of the hypoglossal nerve via the nerve cuff electrode, wherein the stimulus is delivered as a function of the bio-impedance signal; wherein stimulus delivery is initiated before the onset of the future expiratory phase and continued during an entire inspiratory phase, and wherein the method is performed without identifying an onset of an inspiratory phase.

<CIT> discloses an implantable medical device and associated method deliver a therapy to an autonomic nerve. The therapy delivery includes delivering therapeutic low frequency (LF) electrical stimulation pulses to the autonomic nerve and delivering a high frequency electrical signal to the autonomic nerve during the LF frequency stimulation pulse delivery. The high frequency stimulation signal blocks activation of autonomic nerve fibers innervating a non-targeted tissue during the therapeutic LF stimulation pulse delivery.

<CIT> discloses methods, devices, and systems for treating human anemia. The methods, devices, and systems generally include monitoring a patients hemoglobin level and at least one of autonomic balance and inflammatory state to determine the etiology of the anemic state, modulating at least one of a sympathetic or parasympathetic nerve based on the cause of the anemia, monitoring for changes in the patients cardiac activity and state of inflammation, and hemoglobin level. An external neurostimulation system is describes, and well as a chronic implantable system. A method for treating a patient for anemia in conjunction with a renal denervation ablation catheter is also disclosed.

The invention is defined by the enclosed cliams. Embodiments of this presentation incluse an apparatus and method for stimulating nerves at targeted locations, including sympathetic nerves, or spleen, or the vagus nerve and its associated branches toward mitigating negative impacts to hematopoiesis, which is the process by which the body produces blood cells (e.g., white blood cells, red blood cells, platelets). The present disclosure thus provides neuroprotection during chemotherapy that may prevent long-term bone marrow damage. The specific form and method of applying the stimulation innervates patient bone marrow to reduce chemotherapy impacts on hematopoiesis can be either direct electrical stimulation or indirect stimulation. In at least one example embodiment, the stimulation is performed by electrodes, or one or more electrode arrays, that are configured to electrically modulate nerve fibers which regulate hematopoiesis and thus can positively regulate the microenvironment of the bone marrow.

The apparatus provides a user interface to allow the treatment parameters and operation of the unit to be controlled. The user interface communicates either through a wired or wireless communication with the controller circuit, which in turn communicates either through a wired or wireless communication with the electrode driver circuit.

In at least one embodiment this user interface preferably comprises a graphical user interface (GUI) to interface with a control circuit, which in at least one embodiment contains a processor, memory and instructions (e.g., microcontroller, System On a Chip (SoC), Application Specific Integrated Circuit (ASIC), and/or other circuitry for controlling signal output and timing in response to receiving parameters from a user interface). In at least one embodiment, these parameters are based on the patient's physiological state, and are thus a personalized set of stimulation parameters. The controller circuit converts treatment parameters into a series of Building Block Waveforms (BBWs) which are output to Current/Voltage Driver Circuitry (CDC) whose outputs are coupled to one or more electrodes, or electrode arrays, or a combination thereof.

The results demonstrate that the use of the apparatus and method of the present disclosure can significantly reduce adverse impacts to hematopoiesis, and thus improve overall chemotherapy outcomes.

Further aspects of the technology described herein will be brought out in the following portions of the specification, wherein the detailed description is for the purpose of fully disclosing preferred embodiments of the technology without placing limitations thereon.

The technology described herein will be more fully understood by reference to the following drawings which are for illustrative purposes only:.

<FIG> illustrates an example embodiment <NUM> of a system and method for regulating hematopoiesis. An Autonomic Nerve Actuator and Stimulator <NUM> (ANAST) which is coupled (step <NUM>) for acting on the autonomic nervous system <NUM> and directed at (step <NUM>) the bone marrow and spleen <NUM> when addressing (step <NUM>) blood diseases <NUM>, as well as for performing quantitative measurement of effectors <NUM> (step <NUM>).

The method includes the steps of selecting a specific waveform shape based on a system constraint of a waveform generator, and applying a temporal pattern of stimulation to targeted nerves that innervate the bone marrow using the waveform generator, the temporal pattern of stimulation comprising a plurality of single pulse and multiple pulse groups, with constant and randomized inter-pulse intervals between the single pulses and multiple pulse groups, as well as constant or randomized inter-pulse intervals, as well as pulse widths, within the multiple pulse groups themselves.

This method and system for bone marrow innervation stimulation may include an electrode(s) to access the targeted nerves either via implantable or transcutaneous mechanism and a stimulus generator operably coupled to the electrode, where the stimulus generator applies electrical stimulation. Connected to at least one electrode, the stimulus generator (ANAST) is configured to transmit to the electrode an electrical signal for innervating (via either sympathetic or parasympathetic nervous system) the bone marrow. A waveform shape of the electrical signal is shown and described in <FIG> and <FIG>. The electrical signal may also utilize a temporal pattern of stimulation, such as comprising a repeating succession of pulse trains, with each pulse train having a plurality of single pulse and multiple pulse groups, with constant or randomized inter-pulse intervals between the single pulses and multiple pulse groups, and also having constant or randomized inter-pulse intervals, as well as randomized pulse width, within the multiple pulse groups themselves. The pulse train repeating in succession innervates and regulates the microenvironments, which closely affect the hematopoiesis at the bone marrow.

<FIG> illustrates an example embodiment <NUM> of the ANAST system. The ANAST system in this example comprises four submodules: a Graphical User Interface (GUI) <NUM>, Controller (CTL) and/or Firmware (micro-controller (uC)) <NUM>, Current/Voltage Driver Circuitry (CDC) <NUM>, and Electrode Array (EA) <NUM>. It should also be appreciated that the structures and functions described may be divided in other ways across submodules, which may be more or less than exemplified herein, without departing from the teachings of the present disclosure.

The coupling mechanism between any two of the submodules can be realized either via wired (serial or parallel) or wireless (serial) mode. By way of example and not limitation, a preferred connectivity of bi-directional communications is shown between the upper layers and a uni-directional communications to the lowest level being the electrode(s) or electrode array(s) themselves. The overall ANAST system can be configurated for deployment in supporting the regulation of hematopoiesis through innervating the bone marrow.

The configuration of Skin Position <NUM>, as seen at the bottom of the figure, illustrates that at least one embodiment could house together a subsystem of controller (e.g., processor and firmware), driver, and electrode (array) as an implantable unit and leave the GUI as an external unit. The configuration of Skin Position <NUM>, as seen in the center portion of the figure, shows another embodiment which may house together an implantable unit of the driver and electrode (array), and leave a subsystem of GUI and controller (e.g., processor and firmware) as the external unit. Skin Position <NUM>, shown at the upper portion of the figure, depicts yet another embodiment which may house together the GUI, a control circuit (e.g., processor, memory and firmware), and driver as an external unit and an implantable electrode (array). Thus, the positions of the units in relation to the skin depend on the specific embodiments and its applications.

<FIG> and <FIG> illustrates an example embodiment <NUM> of a GUI which issues commands to the controller (CTL), such as comprising a processor (e.g., microprocessor with memory and instructions (firmware)) as shown in <FIG>. It should also be appreciated that other circuit forms may be utilized for generating wave patterns and for controlling operations for initiating the loading of stimulation parameters from the GUI and the setup of stimulation by CDC to the targeted nerve through the electrode(s) (EA), without departing from the teachings of the present disclosure.

In the flow diagram initiation and/or loading <NUM> of the stimulation parameters is performed from the graphic user interface (GUI). These parameters are converted <NUM> into Basic Building Waveforms (BBW), described later for <FIG>, for example according to A/W, A2/W2, IP and T. At block <NUM> clock generators are activated, such as slow clock generators for parameters N, P and D and setting up counters accordingly. Then at block <NUM> a timer is setup for the BBW parameters and constructing the BBW. Then execution reaches block <NUM> which issues time instructions for BBW to the CDC.

A check <NUM> is performed to determine if the active portion (N) of the stimulation has been completed. If it has not completed, then execution returns to block <NUM> with timers being setup again for BBW. Otherwise, if this N phase of stimulation has ended, then execution reaches block <NUM> in <FIG> which determines if the one-shot period (P) has ended.

If the period has ended, then execution returns to block <NUM> in <FIG> where a new period is created. Otherwise, execution reaches block <NUM> which determines if the entire stimulation protocol has been completed. If it has not been completed, then execution returns to block <NUM> in <FIG> where initialization/loading is performed of the parameters from the GUI; otherwise this stimulation processing ends.

<FIG> illustrates an example embodiment <NUM> of current driver circuitry (CDC), which supports both anode and cathode current stimulation waveforms. A controller <NUM>, such as a microcontroller (processor) with memory and firmware; or other electronic circuit(s) configured for generating sequential strings and controlling stimulation operations is coupled to drivers <NUM> and <NUM> through a power/data management (PDM) circuit <NUM>. The controller circuit (herein exemplified as a microcontroller) activates the power/data management unit <NUM> which provides regulated power to the CDC circuit and associated buffer and clock conditioning/generation. The PDM circuit <NUM> can be configured for supporting a CDC circuit in either a wired or wireless mode.

It will be appreciated that stimulation requires current levels to be directed to the electrodes; to which the example below is directed. It should, however, be recognized that the stimulation may be regulated based on either current or voltage without departing from the teachings of the present disclosure. Current can be directed through the electrodes toward reaching a given voltage, or directed toward reaching a certain current level. One of ordinary skill in the art will appreciate the interchange between current and voltage when driving a load.

Each driver <NUM>, <NUM> in this example has a similar structure for driving a stimulation signal at the electrodes. A Digital-to-Analog Converter (DAC) <NUM>, <NUM>, is shown receiving m-bits from the controller. Although these bits are typically sent in parallel, they can be sent as serial information and converted in or before the DAC, without departing from the teachings of the present disclosure.

It should be appreciated that data recovery in a communication sequence can be achieved utilizing either synchronous or asynchronous mode communications. By way of example and not limitation, the embodiment described below utilizes synchronous communications, however, this is not a limitation of the present disclosure which may utilize various communications approaches or protocols for communicating between the controller circuit and current driver circuit.

Following each of the DACs are current mirror circuits <NUM>, <NUM>. The current mirrors are generally utilized here as voltage to current amplifiers, with the proviso described in the previous paragraph. In at least one example embodiment, the current mirrors operate as current amplifiers which have two branches; a reference branch and an output branch, whereby the output current is a multiple of the reference current. The reference current branch is made of N parallel sub-branches such that the overall reference current is equal to the values specified by the N-bit binary code. Each binary bit represents a binary voltage which is converted to current in the drive circuit.

The current mirror could be turn on and off according to the controlled switch (usually connected to the mirror circuitry in serial). This switch is further controlled by the "counter/clock sequence/control) signals provided by the controller circuit (uCT).

The current mirrors output current amplitudes, Ac from CM <NUM>, and Aa from CM <NUM>, respectively to a cathode driver circuit <NUM> and anode driver circuit <NUM>. The pulse width of each anode and cathode pulse is specified by parameters Wk. and Wa, respectively, the resolutions of which are limited by the clock frequency.

It will be appreciated that the generation of these cathode and anode drive waveforms may be accomplished with variations of this circuit, or alternatives, which otherwise are configured for setting signal patterns to drive both cathode and anode circuitry for the stimulation patterns. Accordingly, the present disclosure is not limited to the specific structure exemplified in this figure.

<FIG> illustrates an example embodiment <NUM> of various electrode structures. By way of example, and not limitation, the electrode structures in at least one embodiment can utilize one or more hook electrode <NUM>, cuff electrode <NUM>, needle electrode <NUM>, and surface electrodes <NUM>; while other electrodes known to one of ordinary skill in the art and/or combinations of various electrode types may be utilized without departing from the teachings of the present disclosure. A multiple or a plurality of any electrodes or combinations may be utilized, such as shown in electrode array <NUM> (comprising surface electrodes). In at least one embodiment at least one electrode array is utilized, which for example may be retained in a fixed or stretchable substrate.

<FIG> illustrate an example embodiment <NUM>, <NUM>, <NUM> and <NUM> of parameters for controlling stimulation.

In <FIG> is shown the timing and counters of intraburst stimulation pulse period (T) <NUM>, total stimulation duration (D) <NUM>, burst period of stimulation pulse train protocol (P) <NUM>, intraburst stimulation on (N) <NUM>, value of period that stimulation is off (P-N) <NUM>, which is the idle latency of one-shot period (P) minus the active portion of the stimulation waveform (N), for timing stimulation as set up by the controller to produce the proper waveforms as defined by the parameter set.

The parameters that specify the stimulation waveforms include specification of polarity and mode - LP (leading cathodic or anodic), MO (voltage or current), BP (biphasic), SY (symmetric or asymmetric biphasic); amplitudes, pulse widths, and delay time - Aa, Wa, Ac, Wc, IP, ID, T, N, P, and D. One example embodiment is configured with a micro-controller (uC) and associated memory and firmware for producing the desired stimulus by generating a proper timing sequence for the current driver circuitry (CDC).

A pulse train <NUM> is shown having amplitude (A) <NUM>, intraburst stimulation pulse period (T) <NUM>, pulse width (W) <NUM> and inter-pulse delay (ID) <NUM>. The rectangular black sections of the waveform represent the basic building block waveforms as shown in <FIG>.

In <FIG> is shown a data packet <NUM> for an example communication protocol between the GUI and a controller and its firmware. The data packet fully specifies the stimulation parameters seen at the bottom of <FIG>.

The figure also exemplifies a set of counter specifications and its corresponding feasible ranges for the stimulation parameters. The device architecture is able to provide a wide range of parameters for each individual patient subject.

Using the protocol outlined in this <FIG>, the GUI issues a command to the controller (CTL) in order to initiate the loading of stimulation parameters from the GUI and setup of the stimulus by CDC to the targeted nerve through the electrode or electrode array (EA).

In at least one embodiment a controller circuit (CTL) is exemplified as firmware executing instructions on a micro-controller (uC) to produce the desired stimulus by generating the proper timing sequence for the CDC accordingly. The timing and counters of T, N, P, and D for controlling the stimulation parameters are set up and controlled by the uC to produce the proper waveforms defined by the parameter set. The timing is set to produce the basic building waveform (BBW) block of the pulse trains defined by N and P counters. Moreover, it is allowed to change the basic building waveform block of the pulse trains every P periods.

It should be appreciated that the resolution of the parameters in the time domain is limited by the period of the system clock; whereby increasing the frequency of the system clock allows increasing the resolution of the parameters. The counters of T, N, P, and D are updated according to the u-controller clock or corresponding slow clocks derived by uC. As an example, the resolution of <NUM> is achieved for a uC clock at <NUM>. The clock generators of the uCT are programmed to produce slow clocks for the counters.

In <FIG> is shown examples <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM> of basic timing which can be utilized according to the disclosure for building basic waveform (BBW) blocks of the pulse trains defined by N and P counters.

The first group are configured for generating mono-phasic stimulation as either cathodic stimulation <NUM>, or anodic stimulation <NUM>. In a second group are seen simple bi-phasic stimulation pulses, exemplifying both balanced symmetry (cathodic <NUM> or anodic <NUM> leading), and balanced asymmetry (cathodic <NUM> or anodic <NUM> leading).

The basic building waveforms (BBW) in <FIG> can be realized by various control circuits, for example a microcontroller containing firmware, or by hardware such as System-on-Chip (SoC), or Application-Specific Integrated Circuit (ASIC), or utilizing other forms of sequencing circuitry or combinations thereof. A pulse train (PT) is composed of a series of N (Counter N) basic building waveforms (BBWs). The One-Shot-Protocol (OSP) is in turn composed of a PT and followed by an idle latency of P-N (Counter P). The One-Shot-Protocol (OSP) is repeatedly generated until the counter D has expired.

Moreover, the controller circuit is allowed to change the basic building waveform block of the pulse trains every P period. It will be noted that the resolution of the parameters in the time domain is limited by the system clock frequency. The counters of T, N, P, and D, are updated according to the controller circuit clock or corresponding slow clocks derived by the controller circuit (e.g., processor, microcontroller, SoC, ASIC, and/or other circuitry configured for pulse generation).

Each electrode can be programmed as cathode or anode polarity in a bipolar configuration mode or as cathode or anode in monopolar mode. Furthermore, it is feasible to further support symmetric and asymmetric bi-phasic waveforms with interphasic delay (IP) in either bipolar and/or monopolar configurations.

In <FIG> is seen an example <NUM> of a stimulation waveform, exemplifying a one-shot protocol (cathodic leading). By way of illustrative example, and not limitation, a resolution of <NUM> of waveform <NUM> is achieved for an exemplified microcontroller clock at <NUM>. This figure demonstrates implementation of the stimulation protocol of a balanced symmetric bi-phasic waveform (P) <NUM> with <NUM> seconds on (N) <NUM>, <NUM> seconds off (P-N), and then <NUM> minutes (D) with BBW at <NUM> (F = <NUM>/T) of balanced symmetric biphasic waveforms with the pulse width of <NUM> (W), pulse amplitude of <NUM> mA (A) <NUM> and <NUM>, a <NUM> (IP) <NUM>, cathodic width <NUM> (Wc), anodic width <NUM> (Wa), and T <NUM> exemplified as being <NUM>. This waveform can be realized using <NUM> resolution of the clock for W, IP; a clock of <NUM> for T; a slow clock at <NUM> for N, P; and a slow clock at <NUM> minute for D.

The electrical signal may also be composed of a temporal pattern of stimulation comprising a repeating succession of pulse trains (e.g., the right side of <FIG> showing a second pulse train) each pulse train comprising a plurality of single pulse and multiple pulse groups, with constant or randomized inter-pulse intervals between the single pulses and multiple pulse groups, as well as constant or randomized inter-pulse intervals within the multiple pulse groups themselves, the pulse train repeating in succession to innervate and regulate the microenvironments, which closely affect the hematopoiesis at the bone marrow.

Each electrode can be programmed as cathode or anode polarity in bipolar configuration or as cathode or anode in monopolar mode. Furthermore, it is feasible to further support symmetric and asymmetric biphasic waveform with interphasic delay (IP) in either bipolar and/or monopolar configurations.

The current driver circuitry (CDC) seen in <FIG> supports both anode and cathode current stimulation waveforms as shown in <FIG>. By way of example and not limitation, each driver is composed of a Digital-to-Analog Converter (DAC) and a current mirror (CM) such that the output current amplitude, Aa or Ac, is induced, respectively. The pulse width of each anode and cathode pulse is specified by Wa and Wc, respectively, whose resolution is limited by the clock frequency.

According to the present invention, the ranges for utilizing the ANAST system to augment a chemotherapy treatment are according to the following parameters and ranges:.

Electrical Stimulation (ES) targets the sympathetic nerve innervating bone marrow toward priming its microenvironments after chemotherapy. The results from testing performed in the present disclosure have demonstrated that electrical stimulation of sciatic nerve rescues bone marrow microenvironment from chemotherapy-induced injury, consequently reducing hematologic toxicity and thus mortality.

The therapeutic stimulation provided according to the present disclosure can access (stimulate) the nerves either by an invasive or non-invasive stimulation. Invasive delivery involves the use of direct electrical stimulation to an electrode/electrode array. In non-invasive stimulation the electrical stimulation is created through an indirect mechanism. In at least one embodiment, a form of ultrasound neuromodulation may be utilized in which the ultrasonic particle motions at the nerve are converted into a stimulation force (e.g., electrical stimulation). For example, as these tissues are conductive, particle motion created by an ultrasonic wave induce an electric current density generated by Lorentz forces. This can be enhanced in some cases with magnetic fields generated to pass through the nerve tissue to accentuate the stimulus.

The electrical stimulation described herein is equally applicable to both direct and indirect stimulation of the nerves. By way of example the electrodes/electrode array seen in <FIG> can be replaced with indirect operating electrodes, such as in the form of ultrasonic emitters with the cathode and anode drivers in <FIG> incorporating an ultrasonic oscillator, or otherwise receiving an ultrasonic oscillation signal.

It should also be appreciated that testing was performed at the sciatic nerve in the test results for the sake of simplicity of illustration, as the sciatic nerve notch is readily accessible for stimulation. However, it will be recognized that the described stimulation would have similar effect on other locations in the nervous system, as the nerve fibers have similar structures and neural activation potentials.

It should be appreciated that bone marrow is innervated by both sympathetic nervous system that is emerged from thoracolumbar spinal cord section and parasympathetic nervous system emerging from cranial nerves and sacral spinal cord section. Thus stimulation, at locations or regions of nerve fibers along both nervous systems mentioned above, will eventually reach the bone marrow and is able to regulate hematopoiesis.

<FIG> illustrates an example embodiment <NUM>, <NUM> and <NUM> of electrode array montages <NUM>, <NUM> and <NUM> for achieving a focused stimulation at a specific nerve target, such as a <NUM> x <NUM> electrode array, given by example and not limitation as arrays of various x and y dimensions may be utilized in the present disclosure without limitation.

In these figures, the electrode array montage may comprise either one operating directly or indirectly; for example, the direct stimulation of electrical stimulation through each electrode of the array, or generating an indirect stimulation signal (e.g., ultrasound) which is converted at the nerve it is focused upon into a stimulation. In either case, the desired nerve fiber region can be targeted by (direct or indirect) electrical stimulation if a proper current montage from the array is utilized. Accordingly, the use of focused ultrasound (US) can reach the desired depth of nerve fibers at a predefined focality by properly selecting parameters, such as intensity, frequency, acoustic pressure, burst cycle, pulse rate, and duty cycle, and other US related parameters when activating sympathetic nerves.

Each figure depicts a current scale (e.g., from -<NUM> mA up through + <NUM> mA) on the left for interpreting the electrode states in the montage, with the right of each figure depicting a 3D focusing pattern with a scale in meters at the tissue (nerve embedded). By way of example and not limitation, each electrode (or transducer) in the array may be approximately <NUM> diameter with a <NUM> pitch. These features may be scaled down by an order of magnitude, such as in a larger array, or scaled up by a factor of up to four, with relative pitch being determined by the specific implementation and application.

In <FIG> and <FIG> is seen a first and second electrode array montage, while <FIG> depicts an optimal array montage. In at least one embodiment, "optimal" is defined in this context in the sense of electrical field intensity (m/V<NUM>) and the focality measurement (cm) of the electrical field at the desired stimulation target.

<FIG> illustrates an example embodiment <NUM> of electrical stimulation of the autonomic nerve for modulating peripheral blood cells. The electrical stimulation was performed using different frequencies applied to the nerve (e.g., sciatic nerve in this example test) of SD (Sprague-Dawley) rats for a period of time (e.g., <NUM> minutes), and then blood samples were obtained for performing a complete blood count. The figure illustrates that different frequencies of electrical stimulation have distinct impact on modulating the concentration of different types of blood cells within peripheral blood, which is the consequence of hematopoietic cells mobilizing from bone marrow to peripheral blood.

In the present disclosure other ranges have been tested for the rat experiments, including the use of pulse widths in the range from <NUM> to <NUM> and current amplitudes from <NUM> to <NUM> mA. For human subjects the current amplitude range is set from <NUM> to <NUM> mA.

The figure depicts bar charts for white blood cell concentration <NUM>, platelet concentration <NUM>, red blood cell concentration <NUM> and hemoglobin concentration <NUM>, at frequencies from <NUM> to <NUM>. It can be seen from these charts that these concentration levels can be significantly altered depending on the frequency of stimulation utilized.

Thus, the parameters can be modulated, such as frequency in this case, by ANAST toward optimizing the tradeoffs between different physiological characteristics, such as concentration of white blood cells, red blood cells and hemoglobin.

The use of electrical stimulation according to the present disclosure is applicable to a wide range of chemotherapeutic agents. For the sake of simplicity of illustration, the testing performed is primarily directed to one such agent, "carboplatin", however, the method and apparatus of the present disclosure is not limited to this one chemotherapy agent.

Chemotherapy-induced hematological toxicity includes damage of hematopoietic stem cells and nerve injury within bone marrow microenvironment. Some chemotherapy agents result in nerve damage such as platinum drugs, taxanes, vinca alkaloids, proteasome inhibitors, and alkylating agent, which in turn disrupts the hematopoiesis by deteriorating the innervation of bone marrow via adrenergic, cholinergic, and peptide receptors. Involving with cytokines and chemokines, the disrupted cascade pathways of molecular signaling prevent the normal function of both endosteal and vascular niches, a critical organism for hematopoiesis-differentiation, proliferation, and migration of Hematopoiesis Stem Cells (HSC). Specifically, damage at both endosteal and vascular niches in bone marrow exacerbates the innervation mechanism via neuroreceptors of Beta-<NUM>, Beta-<NUM>, Apha-<NUM>, Alpha-<NUM>. Sympathetic nerve mainly innervates bone marrow by regulating these receptors and trickling down the regulation of molecular pathway signaling, critically the adhesion molecular - CXCL12 (cytokine), and CXCR4 (chemokine). ES applied at the sympathetic nerve has been shown in the present disclosure to provide a high degree of success in preserving the nerve and activating the neuroreceptors and down regulating the critical cytokines and chemokines. Accordingly, the present apparatus and method significantly facilitates hematopoiesis.

As a reference, G-CSF (GranuloCyte Stimulation Factor - a cytokine) has been commonly applied after treatment of various chemotherapy agents. G-CSF activates its own molecular signaling pathways, such as down regulation of CXCL12 in order to facilitate hematopoiesis - differentiation, proliferation, and migration. It should be appreciated that the studies in this present disclosure show that the application of ES outperforms the use of G-CSF in chemotherapy treatments.

<FIG> illustrates an example <NUM>, <NUM>, <NUM> of results from evaluating whether ES can reduce chemotherapy agent-related hematological adverse effect. By way of example and not limitation, the specific chemotherapy agent utilized in this test was carboplatin.

In <FIG> is seen white blood cell concentration for each of the five groups of rats which were tested over two cycles of testing. Male SD rats (weighing <NUM> to <NUM>) were used for studying chemotherapy-induced cytopenia. The rats were divided into five experimental groups: control group; electrical stimulation group; carboplatin group; carboplatin + electrical stimulation (ES) group; and carboplatin + G-CSF group.

In <FIG> and <FIG> are shown bar graphs of the results for each group in day <NUM> of the first and second cycle, respectively. The P-value for statistical analysis (P) is noted in each of these figures.

For each cycle of treatment, a single dose of carboplatin (e.g., <NUM>/kg) or vehicle (saline) was injected intraperitoneally on day <NUM>. On day <NUM>, electrical autonomic nerve stimulation was performed for a specified period (e.g., <NUM> minutes), or a single dose of G-CSF were administrated on the rats according to the different experimental groups. In the example treatment each cycle of treatment is considered to be <NUM> days, however, a treatment cycle could span from one to eight weeks.

In at least one embodiment the nerve stimulation can be generated at frequencies from <NUM>-<NUM>, with a current level from approximately <NUM> mA to <NUM> mA, using a balanced symmetric and asymmetric biphasic waveform. In at least one preferred embodiment, the frequency was approximately <NUM> at a current level of approximately <NUM> mA and an intraburst stimulation period N of two seconds, and a burst period of approximately P=<NUM> seconds.

Blood samples for complete blood count (CBC) were collected in EDTA tubes on various days (day <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>).

Compared to the rats in the carboplatin group, the severity of carboplatin-induced neutropenia was significantly alleviated in the group receiving carboplatin and electrical stimulation according to the present disclosure.

<FIG> illustrate an example <NUM>, <NUM>, <NUM> of results obtained from evaluating hemoglobin levels during testing of the present disclosure at each time point from the rats from the same five experimental groups.

In <FIG> is shown plots for each of the five groups of rats which were tested over two cycles of testing. In <FIG> and <FIG> bar graphs of the results for each group in day <NUM> of the first and second cycle are shown, respectively. The P-value for statistical analysis (P) is noted in each of these figures.

Whether rescue by electrical stimulation or G-CSF, the concentration of hemoglobin was both significantly decreased after carboplatin administration. It can be seen that the ES group has increased concentrations in relation to the control group, while performing ES with the carboplatin provided a notable increase in Hb concentration.

<FIG> illustrate an example <NUM>, <NUM>, <NUM> of results from evaluating platelet concentration at each time point from the rats in the same five experimental groups as described above.

In <FIG> is shown plots for each of the five groups of rats which were tested over two cycles of testing. In <FIG> and <FIG> are bar graphs of the results for each group in day <NUM> of the first and second cycle, respectively. The P-value for statistical analysis (P) is noted in each of these figures. It can be seen in these bar charts that compared to the control group, the platelet counts were significantly reduced in the carboplatin and carboplatin + G-CSF groups. In contrast, there is markedly higher platelet count in the carboplatin + ES group. The data demonstrates that ES alleviates the adverse effect of thrombocytopenia caused by carboplatin.

<FIG> illustrates an example embodiment <NUM> of results indicating survival rates of the rats in the same five groups (control, ES, carboplatin, carboplatin + ES, and carboplatin + G-CSF) as previously described after two cycles of carboplatin over a period of <NUM> days. The figure also depicts the survival rates with the chemotherapy alone (e.g., carboplatin) at a <NUM>% survival rate, and chemically augmented chemotherapy (e.g., carboplatin _ G-CSF) at a <NUM> survival rate; whereas chemotherapy with the electrical stimulation resulted in a <NUM>% survival rate.

The rats in the carboplatin + ES groups had higher survival rates compared to the carboplatin and carboplatin + G-CSF groups. ES is seen according to these tests to reduce the severity of chemotherapy-induced hematology toxicity and treatment-related mortality. Besides the recovery of the neutropenia and thrombocytopenia, electrical stimulation of sympathetic nerves can also decrease the mortality rate after two cycles of carboplatin.

<FIG> illustrates example results <NUM> from the ES augmented treatments <NUM> in relation to preserving the nerve and bone marrow microenvironments. In the upper portion of the figure is shown the two cycles <NUM> and <NUM> of treatments <NUM> and <NUM>, on day <NUM> through day <NUM> and the blood analysis on days <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM>, and BM analysis <NUM>.

The testing utilized immunofluorescence staining of nestin for mesenchymal stem cell, tyrosine hydroxylase (TH+) for sympathetic nerve, and CD31 for vascular to evaluate the alteration of bone marrow microenvironment after three cycles of carboplatin.

As seen in the bar graphs <NUM> and <NUM> at the bottom of the figure, in comparison to the control group, there was more extensive expression of nestin from the rats receiving the chemotherapy (e.g., carboplatin). Use of carboplatin also resulted in reduced expression of TH+ in the sympathetic nerve; however, this reduction was not observed in the carboplatin + ES group. As for the area of TH+ / CD31 evaluated by immunofluorescence staining, the rats in the carboplatin groups expressed lower levels than in the control group, but again this was not observed in the carboplatin + ES group.

The results indicate that exposure to chemotherapeutic agents (e.g., carboplatin) leads to damage of sympathetic nerve and proliferation of mesenchymal stem cells in compensation, and that this can be reversed through ES. These results demonstrated that carboplatin induced the damage of the sympathetic nerve and expansion of nestin+ mesenchymal stem cell within bone marrow, which can be reversed by ES.

After two cycles of chemotherapy, exemplified as using carboplatin with different dosages of <NUM>/kg and <NUM>/kg, the bone marrow of the rats from the five experimental groups was analyzed by immunofluorescence to evaluate the alteration of the bone marrow microenvironment. The bone marrow tissue of rats was stained with nestin, TH and anti-CD31 antibody for mesenchymal stem cell, sympathetic nerve and endothelial cell, respectively. Compared to the control group, the area of the sympathetic nerve along with arteriole significantly decreased and the mesenchymal stem cells increased in the rats from the carboplatin group. Electrical stimulation was found to preserve the nerve structure and bone marrow microenvironment injured by chemotherapy.

<FIG> illustrates an example of results <NUM> in which ES was found to degrade adhesion molecules within bone marrow and mobilize stem cells. In the upper portion of the figure a testing flow <NUM> is shown with carboplatin administration <NUM> at day <NUM>, electrical stimulation (ES) <NUM> on day <NUM>, and bone marrow mRNA tested <NUM> at day <NUM>. Plots are shown on the right side and in the lower portion of the figure for white blood cell concentration <NUM>, CXCL12 mRNA <NUM>, Vcam1 mRNA <NUM> and SCF mRNA <NUM>.

The mRNA level of CXCL12, VCAM1 and SCF within bone marrow were analyzed on the 10th day after carboplatin. There was found to be decreased mRNA level of CXCL12, VCAM1 and SCF in the carboplatin + ES group compared to either the control or carboplatin groups. ES on the left sciatic nerve induced similar results on both sides of the sciatic nerve. The results show that ES can reduce the level CXCL12, VCAM1 and SCF within bone marrow, thus facilitating hematopoietic cell mobilization from bone marrow to the peripheral blood.

To study the etiology of recovery of leukopenia and thrombocytopenia after electrical stimulation, the mRNA of several types of adhesion molecules were analyzed which are responsible for the retention of hematopoietic stem cells within bone marrow. The mRNA level of CXCL12, VCAM1 and SCF were evaluated from the bone marrow of the rats receiving carboplatin and carboplatin + electrical stimulation. Both left (the side of electrical stimulation) and right (without electrical stimulation) femoral bones of the same rat from the carboplatin + electrical stimulation group were evaluated to identify whether electrical stimulation induce local or systemic effect. Accordingly, the results seen in <FIG> also demonstrates that electrical simulation decreases the mRNA level of CXCL12, VCAM1 and SCF, and mobilizes hematopoietic cells from bone marrow to peripheral blood consequently. Electrical stimulation induces systemic rather than local effects, since there was similar presentation from both femoral bone marrow of the same rats.

<FIG> and <FIG> illustrate example results <NUM>, <NUM> and <NUM> of ES promoting hematopoietic regeneration.

In <FIG> is shown bar graphs of Cell number <NUM>, megakaryocytes <NUM> and CD34 ratio of nucleated cells to total nucleated cells <NUM> for a control group, ES group, carboplatin group and carboplatin+ES group, shown at day <NUM> of testing. In <FIG> the testing profile is shown <NUM> with carboplatin <NUM> followed by electrical stimulation <NUM>, evaluating BM <NUM> at day <NUM> in a <NUM>-day cycle. The lower portion of the figure depicts images <NUM> showing an image and associated close up magnification of the bone marrow for the carboplatin group (upper images) and the carboplatin + ES group (lower images).

As seen in these figures, after carboplatin treatment, the cellularity of bone marrow was significantly increased in the carboplatin + ES group, compared to the carboplatin only group. These findings indicated that ES promotes hematopoietic regeneration.

On the 10th day after carboplatin administration, the counts of total cell number, megakaryocytes and CD34+ precursor cells were significantly higher in the carboplatin + ES group compared to the carboplatin group. This data demonstrates that ES promotes hematopoietic regeneration after chemotherapy.

<FIG> illustrates example results <NUM> in which the addition of ES was shown to alter the gene expression profile within the bone marrow. The treatment schema <NUM> is shown with carboplatin administration <NUM> at day <NUM>, followed by ES vehicle <NUM> at day <NUM>, with bone marrow RNA sequencing performed <NUM> on the control, carboplatin and carboplatin + ES groups at Day <NUM> after chemotherapy.

The lower portion of the figure depicts a clustering analysis plot <NUM> of the control group, carboplatin only group, and carboplatin + ES group using Principle Component Analysis.

To identify the alteration of the genetic signature after electrical stimulation, bone marrow bulk mRNA-sequencing of the rats was performed for the control, carboplatin and carboplatin + ES groups. The plot <NUM> demonstrates that the gene modulating cell migration and activation revealed different gene expression levels among the rats of different groups. It can be seen that the data points for carboplatin + ES are clustered close to the control group while is separated from the carboplatin group using Principal Component Analysis - PC1 and PC2. The above demonstrates ES is able to alter the genetic signature which modulates cell migration and activation, and thus facilitate recovery.

<FIG> illustrates an example <NUM> of indirect nerve stimulation, as described in Section <NUM>, that may be utilized in the present disclosure. In some applications rather than directly stimulating the nerve with electrical signals passing through the electrode(s), the stimulation can be indirectly created. In the example shown a focused ultrasonic beam(s) <NUM> from an ultrasonic device <NUM> is direct at the nerve <NUM> (e.g., such as the sciatic nerve shown) being innervated on test subject <NUM>.

<FIG> illustrates an example embodiment <NUM> showing how the use of electrical stimulation (ES) modulates hematopoiesis and bone marrow microenvironment. Sympathetic nerves <NUM> from the spinal cord <NUM>, begin at the first thoracic vertebra of the vertebral column and extend to the second or third lumbar vertebra. The postsynaptic sympathetic nerves enter into bone marrow <NUM> to regulate bone marrow niche. Electrical simulation <NUM> of sympathetic nerve <NUM> within bone marrow can activate the adrenergic receptors <NUM>. on arteriole <NUM>, to promote differentiation <NUM> and facilitate mobilization <NUM> of Hematopoiesis Stem Cell (HSC), which alleviates chemotherapy-related hematologic toxicity.

In conclusion, through electrical stimulating of bone marrow sympathetic nerve, the apparatus and method according to the present disclosure is able to promote hematopoietic mobilization and regeneration, which reduces chemotherapy-induced hematologic toxicity. ES can also rescue sympathetic nerve from chemotherapy-related injury and preserve the bone marrow microenvironment.

Embodiments of the present technology may be described herein with reference to flowchart illustrations of methods and systems according to embodiments of the technology, and/or procedures, algorithms, steps, operations, formulae, or other computational depictions, which may also be implemented as computer program products. In this regard, each block or step of a flowchart, and combinations of blocks (and/or steps) in a flowchart, as well as any procedure, algorithm, step, operation, formula, or computational depiction can be implemented by various means, such as hardware, firmware, and/or software including one or more computer program instructions embodied in computer-readable program code. As will be appreciated, any such computer program instructions may be executed by one or more computer processors, including without limitation a general purpose computer or special purpose computer, or other programmable processing apparatus to produce a machine, such that the computer program instructions which execute on the computer processor(s) or other programmable processing apparatus create means for implementing the function(s) specified.

Accordingly, blocks of the flowcharts, and procedures, algorithms, steps, operations, formulae, or computational depictions described herein support combinations of means for performing the specified function(s), combinations of steps for performing the specified function(s), and computer program instructions, such as embodied in computer-readable program code logic means, for performing the specified function(s). It will also be understood that each block of the flowchart illustrations, as well as any procedures, algorithms, steps, operations, formulae, or computational depictions and combinations thereof described herein, can be implemented by special purpose hardware-based computer systems which perform the specified function(s) or step(s), or combinations of special purpose hardware and computer-readable program code.

It will further be appreciated that as used herein, that the terms processor, hardware processor, computer processor, central processing unit (CPU), and computer are used synonymously to denote a device capable of executing the instructions and communicating with input/output interfaces and/or peripheral devices, and that the terms processor, hardware processor, computer processor, CPU, and computer are intended to encompass single or multiple devices, single core and multicore devices, and variations thereof.

Each and every embodiment of the technology described herein, as well as any aspect, component, or element of any embodiment described herein, and any combination of aspects, components or elements of any embodiment described herein.

As used herein, term "implementation" is intended to include, without limitation, embodiments, examples, or other forms of practicing the technology described herein.

As used herein, the singular terms "a," "an," and "the" may include plural referents unless the context clearly dictates otherwise. Reference to an object in the singular is not intended to mean "one and only one" unless explicitly so stated, but rather "one or more.

Phrasing constructs, such as "A, B and/or C", within the present disclosure describe where either A, B, or C can be present, or any combination of items A, B and C. Phrasing constructs indicating, such as "at least one of" followed by listing a group of elements, indicates that at least one of these group elements is present, which includes any possible combination of the listed elements as applicable.

References in this disclosure referring to "an embodiment", "at least one embodiment" or similar embodiment wording indicates that a particular feature, structure, or characteristic described in connection with a described embodiment is included in at least one embodiment of the present disclosure. Thus, these various embodiment phrases are not necessarily all referring to the same embodiment, or to a specific embodiment which differs from all the other embodiments being described. The embodiment phrasing should be construed to mean that the particular features, structures, or characteristics of a given embodiment may be combined in any suitable manner in one or more embodiments of the disclosed apparatus, system or method.

As used herein, the term "set" refers to a collection of one or more objects. Thus, for example, a set of objects can include a single object or multiple objects.

Relational terms such as first and second, top and bottom, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions.

The terms "comprises," "comprising," "has", "having," "includes", "including," "contains", "containing" or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises, has, includes, contains a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises. a", "includes. a", "contains. a" does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises, has, includes, contains the element.

As used herein, the terms "approximately", "approximate", "substantially", "essentially", and "about", or any other version thereof, are used to describe and account for small variations. When used in conjunction with an event or circumstance, the terms can refer to instances in which the event or circumstance occurs precisely as well as instances in which the event or circumstance occurs to a close approximation. When used in conjunction with a numerical value, the terms can refer to a range of variation of less than or equal to ± <NUM>% of that numerical value, such as less than or equal to ±<NUM>%, less than or equal to ±<NUM>%, less than or equal to ±<NUM>%, less than or equal to ±<NUM>%, less than or equal to ±<NUM> %, less than or equal to ±<NUM>%, less than or equal to ±<NUM> %, or less than or equal to ±<NUM>%. For example, "substantially" aligned can refer to a range of angular variation of less than or equal to ±<NUM>°, such as less than or equal to ±<NUM>°, less than or equal to ±<NUM>°, less than or equal to ±<NUM>°, less than or equal to ±<NUM>°, less than or equal to ±<NUM>°, less than or equal to ±<NUM>°, less than or equal to ±<NUM>°, or less than or equal to ±<NUM>°.

Additionally, amounts, ratios, and other numerical values may sometimes be presented herein in a range format. It is to be understood that such range format is used for convenience and brevity and should be understood flexibly to include numerical values explicitly specified as limits of a range, but also to include all individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly specified. For example, a ratio in the range of about <NUM> to about <NUM> should be understood to include the explicitly recited limits of about <NUM> and about <NUM>, but also to include individual ratios such as about <NUM>, about <NUM>, and about <NUM>, and sub-ranges such as about <NUM> to about <NUM>, about <NUM> to about <NUM>, and so forth.

The term "coupled" as used herein is defined as connected, although not necessarily directly and not necessarily mechanically. A device or structure that is "configured" in a certain way is configured in at least that way, but may also be configured in ways that are not listed.

Benefits, advantages, solutions to problems, and any element(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential features or elements of the technology describes herein or any or all the claims.

In addition, in the foregoing disclosure various features may grouped together in various embodiments for the purpose of streamlining the disclosure. This method of disclosure is not to be interpreted as reflecting an intention that the claimed embodiments require more features than are expressly recited in each claim. Inventive subject matter can lie in less than all features of a single disclosed embodiment.

The abstract of the disclosure is provided to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

The following claims are hereby incorporated into the disclosure, with each claim standing on its own as a separately claimed subject matter.

Claim 1:
An apparatus for generating electrical stimulation innervating patient bone marrow to reduce chemotherapy impacts on hematopoiesis, comprising:
(a) a control circuit (<NUM>) configured for receiving stimulation parameters for electrical stimulation innervating patient bone marrow to reduce chemotherapy impacts on hematopoiesis;
(b) an electrode driver circuit (<NUM>) coupled to said control circuit (<NUM>);
(c) at least one electrode array (<NUM>) configured for receiving drive voltage/current from said electrode driver circuit (<NUM>), said at least one electrode array (<NUM>) configured for being implanted in a patient for innervating patient bone marrow;
(d) wherein said control circuit (<NUM>) is configured for converting said stimulation parameters into a series of basic building block waveforms with amplitudes, pulse width, inter-pulse delay, and stimulation frequencies according to said stimulation parameters, and outputting waveform signals, having pulse trains, each pulse train of which comprises a series of N basic building waveforms, which are output to said electrode driver circuit (<NUM>);
(e) wherein said electrode driver circuit (<NUM>) is configured for receiving said waveform signals from said control circuit (<NUM>), and for driving said at least one electrode array (<NUM>) with a temporal pattern having single pulses and multiple pulse groups separated by inter-pulse intervals; and
(f) whereby said electrical stimulation triggers nerve fibers that innervate patient bone marrow toward priming its microenvironments after chemotherapy toward reducing hematologic toxicity and mortality;
wherein said control circuit (<NUM>), in combination with said electrode driver circuit (<NUM>), are configured for selectively applying electrical pulses to said at least one electrode array (<NUM>) in a waveform consisting of:
(i) a frequency from approximately <NUM> to approximately <NUM>;
(ii) a duration of each phasic pulse of approximately <NUM> to approximately <NUM>;
(iii) a pulse train having a stimulation on period of approximately <NUM> to approximately <NUM> seconds, at a frequency of approximately <NUM> to approximately <NUM>, and a stimulation off period of approximately <NUM> second to approximately <NUM> seconds;
(iv) a pulse train amplitude of approximately <NUM> mA to approximately <NUM> mA; and
(v) a stimulation duration of approximately <NUM> minute to approximately <NUM> minutes with a repeating pattern pulse train.