WO1983002556A1

WO1983002556A1 - An apparatus for influencing the hydrodynamic system in the inner of an ear

Info

Publication number: WO1983002556A1
Application number: PCT/SE1983/000013
Authority: WO
Inventors: Barbara Densert; Ove Densert; Lennart Jonsson
Original assignee: Barbara Densert; Ove Densert; Lennart Jonsson
Priority date: 1982-01-22
Filing date: 1983-01-20
Publication date: 1983-08-04
Also published as: SE8200356L; EP0099388A1

Abstract

Apparatus for influencing the hydrodynamic system in the inner of an ear, which system including the perilymph and endolymph. The task forming the basis of the present invention is to realize an apparatus for influencing the hydrodynamic system in the inner of an ear for influencing the endolymph by the intermediary of the perilymphatic fluid. This task is solved in that the apparatus is provided with first means for generating a static pressure level, second means for varying the static pressure level and third means for interconnecting the first and second means with the auditory meatus.

Description

AN APPARATUS FOR INFLUENCING THE HYDRODYNAMIC SYSTEM IN THE INNER OF AN EAR

TECHNICAL FIELD

The present invention relates to an apparatus for influencing the hydrodynamic system in the inner of the ear, this hydro- dynamic system including the perilymph and endolymph. THE STATE OF THE ART It has been medically established that changes in the endolymph affect the functional properties of the ear, and certain diseases have been indicated as the sources thereof. Examples are Menieres disease with such symptoms as severe disability in hearing, vertigo, tinnitus, clicking inthe ears and so on. In many cases, such changes result in a complete labour incapacitation which are not only because of reduced hearing ability and functional incapability but also to a great extent because of psychological affects which may, in certain cases, be of a drastic nature to say the least, Attempts have been made by surgical means to influence the endolymph, but such operations have proved to be but brief in effect or completely ineffectual, since the endolymph has shown, despite the operation, a tendency to resume the changed state which brought about the initial illness. However, in certain cases, surgical operation has succeeded in countering the symptoms of vertigo but not partial deaf- ness. Results of research into this sector have demonstrated that the pathogenic changes in the endolymph would seem essentially to derive from changes of volume therein. TECHNICAL PROBLEM

The concept forming the basis of the present invention resides in the task of realizing an apparatus for influencing the hydro¬ dynamic system in the inner of the ear for influencing the endolymph by the intermediary of the perilymphatic fluid. SOLUTION

The task forming the basis of the present invention is solved in that the apparatus disclosed by way of introduction displays first means for generating a static pressure level, second means for varying the static pressure level, and third means for interconnection of the first and second means with the auditory meatus. The apparatus may further include fourth means for realizing communication between the auditory eatus and the middle ear for facilitating transfer of the pressure changes realized in the auditory meatus to the middle ear for influencing the hydrodynamic system of the ear. The first means comprise an air pump for generating a desired static pressure level in an air reservoir. The second means comprise a valve for reducing the pressure level in the air reservoi , whereupon the pump once again raises the pressure to the desired level. The third means comprises a tube beween the air reservoir and an earsplogc- for insertion into the external auditory meatus. The fourth means consists of a transmyringeal tube of, for example, Teflon. The first and second means are provided with fifth means for regulating the static pressure to a desired level and further means for regulating the frequency of raising and lowering of the static pressure level. The pump is a diaphragm pump whose diaphragm is mounted at the end of a piston rod which is reciprocal by means of a motor by the inter¬ mediary of a crank connection which is free-running in a direction towards the pressure movement direction of the diaphragm, into which the diaphragm is urged by means of a spring. ADVANTAGES

By means of an apparatus according to the present invention, it has proved to be possible to influence the endolymph by trans¬ mission of pressure changes to the fluid of the perilymph which surrounds the endolymph, for purposes of annulling disease symptoms and attaining an improvement of the condition of the patient, this entailing a re-establ shment of balance, hearing, which in many cases is reduced to complete deafness, obviation of the clicking sensation and tinnitus, whereafter a patient may be expected to be able to resume a fully normal living situation of good quality. DESCRIPTION OF THE ACCOMPANYING DRAWINGS

Fig. 1 is a schematic view, partly in section, of an apparatus according to one embodiment of the present invention. Fig. 2 shows a graphic curve of the pressure changes realized using an apparatus according to the present invention. Fig. 3 is a schematic side elevation of an apparatus according to one embodiment of the present invention. Fig. 4 is a schematic top plan view of the embodiment of Fig. 3. Fig. 5 is a schematic end elevation from the left of the embodiment shown in Figs. 3 and 4. Fig. 6 is a schematic end

OMPI elevation from the right of the embodiment shown in Figs. 3 and 4. Fig. 7 is a section through the embodiment illustrated in Figs. 3-6. Fig. 8 illustrates a graphic curve of the pressure generated by means of the embodiment illsutrated in Figs. 3-7. Fig. 9 is a schematic part section of a further embodiment of an apparatus according to the present invention. Fig. 10 illustrates a similar schematic part section to Fig. 9, but with the parts involved being in a different position. Fig. 11 is a schematic part section of yet a further embodiment of an apparatus according to the present invention. Fig..12 illustrates a similar schematic section to Fig. 11 but with the parts in a different position. Fig. 13 shows a schematic part section of still a further embodiment of an apparatus according to the present invention. Fig. 14 shows a similar schematic part section to Fig. 13, but with the parts in a different position. One embodiment of the present invention will be described in greater detail below.

As is illustrated schematically in Fig. 1, an apparatus according to the present invention may comprise essentially an air reservoir 1 which, by the intermediary of an input 2, is in communication with the ambient air and whose output 3 is connected to an ear-plug 4 and an air pump 5. The input 2 is separated from the output 3 by means of a diaphragm 6. The ear-plug 4 is intended, in a per se conventional manner, to be placed in the external auditory meatus. The output 3 from the air reservoir 1 may suitably consist of a two-way coupling, of which the first is placed in communication, by the intermediary of a hose 7, with the output 8 from the pump 5, and of which the second is placed in communication with the ear-plug 4 by the intermediary of a hose 9. The hoses 7 and 9 may consist of a suitable material, for example rubber or plastics. The pump 5 consists of a diaphragm pump with a per se conventional diaphragm 10 which is mounted in a pump housing 11. Approximately in its centre, the membrane 10 is placed under tension between a top washer 12 and a bottom washer 13 by means of a piston rod 14 and a screw 15. An intake valve 16 is disposed in the diaphragm 10 and the washers 12 and 13. The piston rod 14 extends through the pump housing 11 and an adjustment nut 17 disposed therein. A compression spring 18 extends between the nut 17 and the top washer 12, the compression force of the spring being adjustable by means of the nut 17. Further-

O P more, an intake orifice 19 and a delivery orifice 20 are disposed in the housing 11. A valve 21 is disposed in the delivery orifice 20 and is urged against the orifice for closure thereof by means of a leaf spring 22. A screw 23 is further disposed in the output 8 from the pump 5, by means of which screw the pressure in the hoses 7 and 9 and in the chamber 6a of the air reservoir can be relieved as desired.

The rod 14 is controlled by means of two guide rolls 24 and 25 and is coupled to a crank 26 by the intermediary of an arm 27 pivotally disposed on the end of the rod 14. The arm 27 has an ^• elongate hole 28 in which the crank pin 26 runs. The crank pin 26 is mounted on a disk 29 which is connected, by the intermediary of a shaft 30, to, for example, a speed-regulated electric motor.

The method of operation of the apparatus described above will now be described in greater detail.

When the shaft 30 is turned by means of an electric motor, the disk 29 fixedly connected thereto will rotate, like the crank pin 26, whereby the rod 14 will be vertically reciprocated in the pump housing 14 and entrain the membrane 10 and the parts connected thereto. The spring 18 and the^" elongate hole 28 in the arm 27 entail relatively accurate regulation of the pressure level in the hoses 7, 9 and in the chamber 6a. This pressure level will remain static on condition that the screw 23 is tightened so as to prevent any leakage at the screw. As will be apparent from Fig. 2, the pressure level A can be obtained by actuating the nut 17. If the screw 23 is actuated for reducing the pressure in the hoses 7, 9 and the chamber 6a, the pressure will fall following the pressure curve in Fig. 2 to level B, whereupon the pressure will be immediately raised because of the function of the diaphragm 10 to level A. The rate of lowering and increasing depends, naturally, on the speed at which the shaft 30 and the disk 26 rotate. The parameters for the pressure curve shown in Fig. 2 are, thus, determined by the spring 18, the screw 23 and the speed of the electric motor.

Experiments have shown it to be suitable with an amplitude of approximately 25 cm water column and a frequency of 3-6 Hz. It should further be observed that it has been found to be appropriate if the pressure variations follow as good as a sinus curve.

In order to facilitate transfer of the pressure changes from the

OMPI auditory meatus in which the ear-plug 4 is placed, there is provided a transmyringeal tube of preferably Teflon to the middle ear. From the middle ear, transfer of the pressure changes is effected as good as immediately to the hydrodynamic system of the ear and, in particular, to the perilymphatic fluid, whereby there will be obtained an influence on the endolymphatic pressure since the fluids in the inner ear are incompressible.

As a result of the pressure changes in the perilymph, there will further be obtained a reduction of the volume of the endolymph and it may furthermore be assumed that the endolymph is shifted in the labyrinth towards the endolymph duct and sac. The parameters illustrated in Fig. 2 of the pressure change curve are, naturally, not constant fro'm case to case but must be adapted to suit different individuals and thereby different changes of the endolymph. The effects attained by means of the apparatus according to the present invention would seem to entail a considerable improvement of the condition of the patient, this involving a restoration of the sense of balance, the. hearing ability, which, in many cases, is reduced to complete deafness, a cessation of clicking sensations and tinnitus, whereafter patients may be expected to return to a normal way of life of excellent quality.

As a result of the apparatus according to the present invention, there will be obtained a relatively lengthy restoration of the volume of the endolymph as a result of the pressure changes realized in the perilymph.

The embodiment of the present invention illustrated in Figs. 3- 6 comprises a pump housing 50, a diaphragm 51, a clamping ring 52, a motor 53 on a frame 54. The motor 53 is coupled, by the intermediary of gearing 56, to a crank shaft 57 with a first crank disk 58 of fixed crank radius, and a second crank disk 59 of adjustable crank radius. The crank disk 58 is coupled, by the intermediary of a crank cheek, to a modulator piston 61. The output 62 is to be connected to an ear-plug by means of, for example, a hose, whereupon the ear-plug is placed in an ear 63. As will be apparent from Fig. 5, the piston rod of the pump piston 60 is designed with a free stroke gap 66 and spring-biased arms. The modulator piston 61 is provided with a piston rod 64 which 1s connected to the crank cheek on the adjustable crank. Fig. 7 illustrates the valve arrangement and piston arrangement

OMP within the pump housing 50 proper, and Fig. 8 illustrates the basic pressure which is adjustable using the springs, illustrated in Fig. 5, between the pump housing and the arms on the piston rod with the free stroke gap the modulating pressure being adjustable using the crank radius on the crank disk 59.

■The spring force illustrated in Fig. 7 is realized by means of the springs of Fig. 5. It should further be observed that the pump piston 60 is illustrated at its upper dead point in Figs. 3-7 and the modulator piston 61 is illustrated at 0.25-0.5 crank shaft turns before the upper dead point. On continued rotation of the crank shaft in the direction of the arrows in Figs. 5 and 6, the pump piston 60 will disengage from the crank because of the free stroke gap (Fig.5). The spring force merely urges the pump piston 60 downwardly. A basic pressure which is determined by the effective piston area of the pump piston and pf (Fig. 7) is built up. The basic pressure is propagated from Vp to Vv to Vm and to the ear 63 (Fig. 7). The volume Vm increases until the modulator piston 61 has reached its upper dead point. When the modulator piston 61 passes the dead point, the volume Vm is reduced and the pressure increases in Vm and Vv and the ear {but not in Vp which is pressure-restricted by the one-way valve 65). Pressure increases to maximum when the modulator piston passes its lower dead point. The pressure increase may be varied using the adjustable crank radius of the crank disk. The pressure falls once again when the modulator piston passes its lower dead point. When the pressure in Vm, Vv and ^"the ear has fallen to the basic pressure level, the one-way valve opens and the (concurrently) newly replenished pump pⁱston can urge out air for restoring the basic pressure if air has leaked out at the ear-plug or elsewhere.

Fig. 9 and 10 illustrate an embodiment of the present invention with a suction intake valve positively controlled by the movement of the crank cheek, Fig. 9 illustrating the pump stroke and Fig. 10 illustrating the suction stroke.

Fig. 11 and 12 illustrate yet another embodiment with the suction intake valve controlled by excess pressure and partial vacuum in the pump cylinder. Here, a free stroke groove is used instead of free stroke gap. Fig. 9 illustrates the pump stroke and Fig. 10 the suction stroke.

In Figs. 9, 10, 11 and 12, the crank shaft is turned through

O PI 90 from its real position clarifying the inlet and outlet roots for the air.

Fig. 13 and 14 show one embodiment of an extremely practical design.-This embodiment includes valves according to Fig. 11 and 12, 5 but the spring for realizing the pf pressure is placed asymmetrically and provided with an adjustable anchorage. The free stroke gap provides complete freedom for the spring to "buckle up" the diaphragm and thereby create a clearly-determined basic pressure (uninfluenced by the movement of the crank pin). The embodiment illustrated in Fig. 10 13 and 14 is extremely simple to reproduce and may readily be set at desired values of basic pressure and modulating pressure.

Claims

1. An apparatus for influencing the hydrodynamic system of the inner of an ear, which system including the perilymph and the endolymph, c h a r a c t e r !^' z e d by first means for generating a static pressure level, second means for varying the static pressure level, and third means for interconnecting said first and said second means with the auditory meatus.

2. An apparatus according to claim 1, c h a r a c t e r i z e d by fourth means for realizing communication between the auditory meatus and the middle ear for facilitating transfer of the pressure changes realized in the auditory meatus to the middle ear for influencing the hydrodynamic system of the ear.

3. An apparatus according to claim 1, c h a r a c t e i z e d in that said first means include an air pump for generating the desired static pressure level in an air reservoir.

4. An apparatus according to claims 1 and 3, c h a r a c t e r ¬ i z e d in that said second means include a valve for reducing the pressure level in the air reservoir whereupon the pump once again raises the pressure level to that desired.

5. An apparatus according to claim 1, c h a r a c t e r i z e d in that said third means include a hose between the air reservoir and

OMPI an ear-plug for insertion in the auditory meatus.

6. An apapratus according to claim 2, c h a r a c t e r i z e d in that said fourth means consist of a transmyringeal tube of, for example, Teflon.

7. An apparatus according to any one of claims 1, 3 and 4, c h a r a c t e r i z e d in that said first and second means are associated with fifth means for regulating the static pressure level at a desired level and further means for regulating the frequency of raisings and lowerings of the static pressure level.

8. An apparatus according to claims 3 and 7, c h a r a c t e r ¬ i z e d in that the pump is a diaphragm pump, whose diaphragm is mounted at the end of a piston rod which is reciprocally moveable by means of a crank coupling with free run in the direction of the pressure movement direction of the diaphragm, in which the diaphragm is urged by means of a spring.

OMPI