Vibration pattern for vibration stimulation

Abstract

A method of treatment by vibration stimulation is provided. The method includes providing an expandable stimulation member adapted to impart vibrations to body tissue of a human subject; introducing the stimulation member into a body cavity of the human subject; expanding the stimulation member to a volume such that the stimulation member abuts against body tissue within the body cavity; bringing the stimulation member to vibrate such that vibrations are imparted to the body tissue in the body cavity of the human subject according to a vibration pattern, wherein the vibration pattern includes a main periodic element of a first frequency and an excitation stimulus of a second frequency higher than the first frequency.

Claims

1. A method of treatment of a human subject, comprising the steps of: introducing a stimulation member into a nasal cavity of a human subject, said stimulation member being adapted to impart vibrations to body tissue of the human subject; anchoring the stimulation member to the head of the human subject by means of at least one of a head band, a facial mask, a pair of glasses, and a helmet; selecting a first frequency by: imparting vibrations to said nasal cavity at a variable frequency; gradually adjusting the variable frequency up to a maximum frequency; monitoring a bodily response to the treatment, the bodily response being indicative of a physiological condition of the subject; determining the first frequency based on the monitored bodily response; and imparting vibrations to the nasal cavity of the human subject according to a vibration pattern, wherein the vibration pattern comprises a main periodic element with the first frequency and an excitation stimulus with a second frequency higher than the first frequency, and the second frequency is within a range of 1.5-5 times as high as the first frequency, wherein the vibrations are generated by one or more of: an electroactive material, wherein the stimulation member comprises said electroactive material, the electroactive material being controlled such that the stimulation member vibrates according to the vibration pattern; and a vibration generator comprising a frequency regulating module configured to provide vibrations according to the vibration pattern to a pressurized fluid in the stimulation member, and wherein the step of monitoring a bodily response further comprises one or more of the steps of measuring a bodily response selected from a list comprising: nasal secretion, sneeze frequency, pain sensation, pupil size.

2. The method according to claim 1, wherein the first frequency is within a range of 10-100 Hz.

3. The method according to claim 1, wherein the vibration pattern has a continuous waveform.

4. The method according to claim 1, wherein the main periodic element is provided by a main stimulus of the first frequency, wherein the main stimulus is at least partly superposed with the excitation stimulus.

5. The method according to claim 1, wherein the main periodic element is provided by a vibration profile repetitively initiated at the first frequency, the vibration profile comprising a stimulation phase including the excitation stimulus and a rest phase.

6. The method according to claim 5, wherein the rest phase has at least a same duration as the stimulation phase.

7. The method according to claim 1, wherein the step of introducing the stimulation member to the nasal cavity further comprises: expanding the stimulation member to a volume such that the stimulation member abuts against body tissue in the nasal cavity at a pressure in a range of from 50 to 120 mbar.

8. The method according to claim 1, wherein the first frequency is within a range from of 50 to 70 Hz and the second frequency is within a range of from 110 to 320 Hz.

9. The method according to claim 1, further comprising the step of selecting the second frequency by: gradually adjusting a frequency of the excitation stimulus from a value of the selected first frequency up to the maximum frequency; monitoring, by a measuring device, a bodily response to the treatment, the bodily response being indicative of a physiological condition of the subject; and setting the second frequency to a frequency within 10 Hz of a value of the frequency of the excitation stimulus at which the bodily response monitored during gradually adjusting the frequency of the excitation stimulus, is maximized.

10. The method according to claim 1, wherein the stimulation member is expandable and the step of introducing further comprises: expanding the stimulation member to a volume such that the stimulation member abuts against body tissue in the nasal cavity.

11. The method according to claim 1, wherein the vibrations are generated by the electroactive material, and the stimulation member comprises said electroactive material, the electroactive material being controlled such that the stimulation member vibrates according to the vibration pattern.

12. The method according to claim 11, wherein the electroactive material is a dielectric elastomer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above, as well as additional objects, features and advantages of the present invention, will be better understood through the following illustrative and non-limiting detailed description of preferred embodiments of the present invention, with reference to the appended drawings, in which:

(2) FIG. 1a shows a device for vibration stimulation according an embodiment of the present invention;

(3) FIG. 1b shows an example of a vibration pattern obtainable by the device shown in FIG. 1a;

(4) FIG. 1c shows another example of a vibration pattern obtainable by the device shown in FIG. 1a;

(5) FIG. 2a shows a device for vibration stimulation according another embodiment of the present invention;

(6) FIG. 2b shows an example of a vibration pattern obtainable by the device shown in FIG. 2a;

(7) FIG. 3 shows a stimulation member of the device positioned within the nasal cavity of a human subject; and

(8) FIG. 4 shows a stimulation member and an anchoring member of a device according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(9) The present invention will now be described with reference to the accompanying drawings, wherein the same or similar elements are identified with the same reference numeral.

(10) All the figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate the invention, wherein other parts may be omitted or merely suggested.

(11) With reference to FIGS. 1a-1c, a device for vibration stimulation according to an embodiment of the present invention will be described. FIG. 1a is a schematic view of the device, and FIGS. 1b and 1c show two examples of vibration patterns obtainable by the device.

(12) FIG. 1a shows a vibration stimulation device 1 comprising a stimulation member 12 adapted to impart vibrations to a body tissue of a subject, and a vibration generator 10. In the present embodiment, the vibrations are generated by fluid pressure, wherein the stimulation member 12 may comprise an expandable balloon (or catheter or bladder) in fluid communication with the vibration generator 10 via a tubing 13. Hence, the stimulation member 12 may comprise a chamber for containing fluid supplied by the tubing 13.

(13) The stimulation member 12 may be arranged in a collapsed (or less expanded) state for insertion in a body cavity, such as the nasal cavity or intestine, of a human subject. When inserted, the stimulation member 12 may be expanded to a volume such that an outer surface of the stimulation member abuts against the inside of the body cavity (which will be explained in more detail further on with reference to FIG. 3). The supply of fluid to the stimulation member 12 via the tubing 13 influences the volume and degree of expansion of the stimulation member 12.

(14) The stimulation member 12 may be made of a material not chemically or biologically affecting body tissues with which it comes into contact and the outer surface may be adapted to reduce friction between the stimulation member 12 and the surrounding tissue. The stimulation member 12 may e.g. be made of a material providing a smooth outer surface or be coated with a lubricant, such as e.g. a paraffin solution. Further, the stimulation member 12 may be elastic, whereby its surface area may depend on the fluid pressure in the stimulation member. Alternatively, the stimulation member 12 may be inelastic. Non-limiting examples of materials, which the stimulation member 12 may be made of, are plastic materials or rubber materials. In some instances, the stimulation member 12 may be made of latex.

(15) Further details and embodiments of the stimulation member are described in the published international patent application WO 2008/138997, by the same applicant, which is hereby incorporated by reference.

(16) The device 1 may include a pressure regulating module 15 (e.g. a pressure pump) adapted to pressurize fluid (such as air) entered via an inlet 18. The pressure regulating module 15 is in fluid communication with the vibration generator 10, which comprises a frequency regulating module 17 (e.g. an oscillation pump) adapted to provide vibrations to the pressurized fluid. The frequency regulating module 17 is adapted to provide vibrations of a selected frequency/frequencies and may also be adapted to regulate the amplitude of the vibrations. The pressurized fluid and the vibrations are transmitted (or supplied) via the tubing 13 to the stimulation member 12. The vibration generator 10 further comprises a gate 19, such as a valve (e.g. an electromechanical valve), arranged to selectively allow the transmission of vibrations from the frequency regulating module 17 to the stimulation member 12, e.g. by opening and closing the fluid communication there between.

(17) It will be appreciated that all of, or two of, the pressure regulating module 15, the frequency regulating module 17 and the gate 19 may be comprised in the same module, even though they are schematically depicted as separate units in FIG. 1a. Further, it will be appreciated that the pressure regulating module 15 either may be an external module connected to the vibration generator 10 of the device 1, or comprised in the device 1.

(18) In the present embodiment, the frequency regulating module 17 and the gate 19 are connected directly on a main fluid communication line connecting the pressure regulating module 15 to the tubing 13. Alternatively, the frequency regulating module and the gate may be arranged on a separate fluid communication line connected to the main fluid communication line via a T-junction.

(19) Optionally, the device 1 may comprise a pressure sensor (not shown), such as a manometer adapted to measure the fluid pressure in the device 1, and/or a safety valve (not shown) arranged to release fluid from the device 1 if the pressure exceeds a predetermined threshold.

(20) The device 1 further comprises a vibration controller 14 configured to control the vibration generator 10 to bring the stimulation member 12 to vibrate according to a vibration pattern. The vibration controller 14 may be configured to control the frequency regulating module 17 and thereby the frequency (and optionally also the amplitude) of the vibrations, and the opening and closing of the gate 19 (or valve) and thereby any interruptions in the vibrations. Optionally, the vibration controller 14 may further be configured to control the pressure regulating module 15 and thereby the fluid pressure in the device 1.

(21) Two examples of vibration patterns, according to which the stimulation member 12 of the device 1 according to the present embodiment may be brought to vibrate, will be described with reference to FIGS. 1b and 1c.

(22) Each one of FIGS. 1b and 1c schematically illustrate how the abutting pressure p of the stimulation member 12 against the body tissue varies over time t. The pattern according to which the pressure varies is the vibration pattern (or vibration signal) of the device 1. The p-axis in FIGS. 1b and 1c may alternatively be seen as the spatial shift of the stimulation member 12 causing the vibrations or the fluid pressure inside the stimulation member 12.

(23) The vibration pattern shown in FIG. 1b comprises a vibration profile 150 including a stimulation phase 151 and a rest phase 152, wherein the vibration profile 150 is repetitively initiated at a first frequency. The stimulation phase 151 comprises an excitation stimulus 170, which represents a shift (such as one or more increases and/or decreases) in the abutting pressure p. The excitation stimulus 170 has a second frequency being higher than the first frequency and may have a substantially continuous waveform, such as in the present example with a sine waveform. Continuous waveforms in the vibration pattern allows constructing the stimulation member 12 (and other parts of the device 1) in more flexible materials.

(24) In the present example, the stimulation phase 151 comprises one period of the excitation stimulus 170, but it may alternatively comprise more than one period, such as 1.5, 2, 2.5, 3, or more periods. The number of periods may be selected based on the relation between the first and second frequencies and the desired lengths of the stimulation and rest phases 151, 152. In the present example, the second frequency is approximately 3.7 times as high as the first frequency and the rest phase 152 is approximately 2.7 times as long as the stimulation phase 151. In the present example, the first frequency may be set to approximately 68 Hz (or around 60-80 Hz) and the second frequency to approximately 250 Hz (or around 110-320 Hz) for targeting different parts of the nervous system being sensitive to vibrations. However, other first and second frequencies are also envisaged, as they may be selected based on the purpose of the vibration stimulation treatment.

(25) The rest phase 152 represents an interruption in the vibrations provided during the stimulation phase 151. Further, the abutting pressure p may be constant during the rest phase 152, whereby no vibrations are imparted to the body tissue during that phase. The alternation between the stimulation phase 151 and the rest phase 152 provides a main periodic element of the first frequency to the vibration pattern. For example, the main periodic element may be seen as the periodicity provided by repetitive alternation between the stimulation phase 151 and the rest phase 152.

(26) The vibration pattern shown in FIG. 1c is similar to the vibration pattern described with reference to FIG. 1b except that the excitation stimulus 171 (in the stimulation phase 151 of the vibration profile 150) is formed as an offset cosine wave. In this embodiment, the vibration pattern and its time derivative are continuous. This is achieved by providing an excitation stimulus 171 with the time derivative equal to zero at both end points. In the present example, the stimulation phase 151 comprises one period of the excitation stimulus 171, but it may alternatively comprise more than one period.

(27) An example of how the above described vibration patterns may be provided by the device 1 according to the present embodiment will be described in the following. The vibration controller 14 controls the frequency regulating module 17 to provide vibrations of the second frequency in the pressurized fluid from the pressure regulating module 15. Further, the vibration controller 14 controls the gate 19 to repetitively open and close, such that transmission of the vibrations to the stimulating member 12 is allowed during the stimulation phases 151 and blocked during the rest phases 152. The timing of opening and closing the valve may be accurately controlled to achieve a continuity in the vibration pattern. Alternatively, the vibration controller 14 may be configured to control the frequency generator 17 to provide pulses of vibrations of the second frequency, such that the pulses are repetitively initiated at the first frequency, whereby a valve 19 may not be required.

(28) A device for vibration stimulation according to another embodiment of the present invention will be described with reference to FIG. 2a. The basic structure and basic operation principle of the device 2 and each one of its constituents shown in FIG. 2a may be the same as the basic structure and basic operation principle of the device 1 and its constituents shown in FIG. 1a, except for the configuration of the vibration generator 20 and the vibration controller 24.

(29) In the present embodiment, the vibration generator 20 comprises a first frequency regulating module 26 and a second frequency regulating module 27. Each one of the first and second frequency regulating modules 26, 27 are in fluid communication with the pressure regulating module 25, which is arranged to pressurize fluid taken in at the inlet 28. The vibration controller 24 is configured to control the first frequency regulating module 26 to provide the pressurized fluid with vibrations of the first frequency and the second frequency regulating module 27 to provide the pressurized fluid with vibrations of the second frequency (which is higher than the first frequency). The outputs (i.e., the vibrations in the pressurized fluid) from the first and second frequency regulating modules 26, 27 are added, such that pressurized fluid with vibrations of the first frequency superposed with vibrations of the second frequency is provided and may be transmitted via the tubing 23 to the stimulation member 22. Optionally, the device 1 may comprise one or more gates, such as valves, (not shown) for controlling the transmission of vibrations from the first and/or second generating modules 26, 27.

(30) An example of a vibration pattern, according to which the stimulation member 22 of the device 2 according to the present embodiment may be brought to vibrate, will be described with reference to FIG. 2b.

(31) FIG. 2b schematically illustrates how the abutting pressure p of the stimulation member 22 against the body tissue varies over time t. The pattern according to which the pressure varies is the vibration pattern (or vibration signal) of the device 2. The p-axis in FIG. 2b may alternatively be seen as the spatial shift of the stimulation member 22 causing the vibrations or the fluid pressure inside the stimulation member 22.

(32) The vibration pattern comprises a main stimulus of the first frequency, the period of which is denoted with reference number 250 in FIG. 2b. The main stimulus represents a shift (such as one or more increases and/or decreases) in the abutting pressure p occurring at the first frequency and is provided by the first frequency regulating module 26. Superposed with the main stimulus is an excitation stimulus of the second frequency, the period of which is denoted with reference number 251 in FIG. 2b. The excitation stimulus is provided by the second frequency regulating module 27. Hence, the main stimulus acts as a carrier wave for the excitation stimulus, as the vibration outputs from the first and second frequency regulating modules 26, 27 are added.

(33) The second frequency is higher than the first frequency, and in this non-limiting example, the second frequency is approximately 4.4 times as high as the first frequency. Hence, the vibration pattern comprises a main periodic element of the first frequency provided by the main stimulus (or the periodicity of the main stimulus), and an element (or component) of a higher frequency provided by the excitation stimulus. In the present example, the first frequency may be set to approximately 68 Hz (or around 60-80 Hz) and the second frequency to approximately 300 Hz (or around 110-320 Hz) for targeting different sensitivity ranges of the receptors sensitive to vibrations in the body. However, other first and second frequencies are also envisaged, as they may be selected based on the purpose of the vibration stimulation treatment.

(34) In the present example, the main stimulus and the excitation stimulus are continuously superposed (without interruptions). However, the excitation stimulus may alternatively be partly superposed with the main stimulus, such that phases with the two superposed stimuli are alternated with phases with the non-superposed main stimulus.

(35) Further, the amplitude of the excitation stimulus may be lower than the amplitude of the main stimulus, whereby the main stimulus may dominate the vibration pattern, or alternatively, the amplitude of the excitation stimulus may be higher than the amplitude of the main stimulus, whereby the excitation stimulus may dominate the vibration pattern. Further, the amplitude of the excitation stimulus may vary over time, such as within each phase of the main stimulus.

(36) The Pacinian corpuscles are more sensitive to velocity and acceleration as the vibration frequency increases. Hence, if the total amplitude of the vibration pattern is limited, it may be advantageous to have a lower amplitude for the excitation stimulus than for the main stimulus, since the receptors are more sensitive at higher frequencies (such as between 200 Hz and 300 Hz). However, this may provide that the achieved velocities and accelerations (of the vibrations) are smaller than what would be obtainable with the same amplitude limitation in the embodiment wherein the main periodic element is provided by the vibration profile with a stimulation phase and a rest phase. Thus, the embodiment wherein the main periodic element is provided by the vibration profile with a stimulation phase and a rest phase may be advantageous for obtaining higher velocities and accelerations of the vibrations.

(37) It will be appreciated that shapes of the vibration patterns illustrated in the Figures are schematic and show the principles of the embodiments of the present invention.

(38) With reference to FIG. 3, an embodiment of a method of treatment of a human subject by means of device according to an embodiment of the present invention will be described. FIG. 3 shows a stimulation member 32 inside the nasal cavity 35. The stimulation member 32 is connected to a tubing 33. For instance, the device may be constructed as any one of the devices described with reference to FIGS. 1a and 2a.

(39) The purpose of the method according to the present embodiment may e.g. be to treat a disease associated with the activity of hypothalamus (e.g., migraine, ALS, Mnire's disease and heart arrhythmia) or rhinitis.

(40) At a first stage, the stimulating member 32 is arranged in a collapsed (first) state, in which its size is sufficiently small to be introduced into the nasal cavity 35 of the human subject 30. The stimulation member 32 may also be provided with a lubricant, e.g. paraffin, to facilitate the introduction through the nostril. The stimulation member 32 is inserted into the nasal cavity 35 and if any disease associated with the activity of hypothalamus is to be treated, the stimulation member may be adapted for stimulation in the posterior part of the nasal cavity 35 (as shown in FIG. 3), and if e.g. rhinitis is to be treated, the stimulation member 32 may be adapted for stimulation in the anterior part of the nasal cavity (not shown). The stimulation member may be secured to the human subject 30 via anchoring means for reducing the risk of displacement of the stimulation member 32 during the treatment. Subsequently, the stimulation member 32 is pressurized such that it expands until it abuts the tissue of the selected parts of the nasal cavity 35 with a desired pressure (which may be monitored by the manometer), such as 20-120 mbar. Subsequently, the vibration controller controls the vibration generator to bring the stimulation member 32 to vibrate according to a vibration pattern comprising a main periodic element of a first frequency and an excitation stimulus of a second frequency higher than the first frequency (such as any of the previously described vibration patterns). The vibration treatment may e.g. last 1 minute to 30 minutes.

(41) With reference to FIG. 4, an anchoring means and an alternative vibration generator of a device according to an embodiment of the present invention will be described. It will be appreciated that the following example may be combined with any one of the preceding examples described above.

(42) FIG. 4 shows a stimulation member of the device inserted in the nasal cavity of a human subject 40. The device comprises anchoring means 46, which may comprise a headband 47, as shown in FIG. 4. Alternatively, the anchoring means may comprise a facial mask, a pair of glasses, a helmet, a belt, a cuff, a vest and/or an adhesive patch (not shown).

(43) Headbands, facial masks, glasses and helmets are in particular suitable for anchoring the stimulation member in the nasal cavity and at parts of the head and neck. Belts may be suitable for anchoring the stimulation member at the torso, and cuffs may be suitable for anchoring the stimulation member at the extremities, i.e. an arm or a leg.

(44) Further, the device comprises a pipe 44 (or rod) mounted to the headband 47 via an adjustable joint 42 and vibration generator comprising a squeeze actuator 48 mounted to the pipe 44 via a connector 49 (such as a mechanical or electrical connector). The squeeze actuator 48 may comprise a sleeve circumferentially mounted around a tubing 43 connected to the stimulation member and may be electrically connected to a vibration controller via wiring 41. The wiring 41 may be provided inside the pipe 44 to prevent the wiring from interfering with the treatment. In the present embodiment, a pressure regulating module (not shown) provides pressurized fluid via the tubing 43 to the stimulation member. The vibration controller is configured to control the squeeze actuator 48 to generate vibrations in the pressurized fluid according to a vibration pattern (such as described above). The squeeze actuator 48 provides the vibrations to the fluid by squeezing the tubing 43 according to the vibration pattern.

(45) While specific embodiments have been described, the skilled person will understand that various modifications and alterations are conceivable within the scope as defined in the appended claims.

(46) For example, even though only vibrations generated by fluid pressure are described with reference to the drawings, it will be appreciated that the vibrations may equally be generated by other means, such as by a motor with an eccentric weight positioned in, or in proximity to, the stimulation member, by electroactive material or any other convenient vibration generating means.

(47) The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.