Surgery: kinesitherapy – Kinesitherapy – Vibrator
Reexamination Certificate
2001-03-14
2003-10-07
DeMille, Danton D. (Department: 3764)
Surgery: kinesitherapy
Kinesitherapy
Vibrator
C601S148000, C600S559000
Reexamination Certificate
active
06629938
ABSTRACT:
FIELD OF THE INVENTION
The present Invention relates to an apparatus for treatment of Ménière's disease and similar conditions by producing variations in positive air pressure, which are transmitted to one of the ears of a patient.
BACKGROUND OF THE INVENTION
Ménière's disease can be treated by affecting the pressure in the internal ear, in particular the endolymphatic system.
WO 83/02556 discloses an apparatus for influencing the hydrodynamic system of the inner ear comprising a displaceable diaphragm forming the wall of an air pressure generating chamber, the diaphragm being reciprocally displaceable by means of a crank coupling in a direction away from the chamber against the force of a spring coil.
WO 93/08775 discloses an air pressure generator for the treatment of Ménière's disease by pressure pulses generated by a flexible membrane forming a wall in a pressure generating chamber, the membrane being displaced by actuation means rigidly coupled to the shaft of an electrical motor.
WO 97/23178 discloses a device for affecting the hydrodynamic system of the inner ear comprising first means for generating a static pressure level and second means for causing a variation of that level in accordance with a predetermined program controlled by a control unit. Each of the first and second means comprise a flexible membrane. Also in this known apparatus one half of the reciprocating movement of the diaphragm, the one in which the diaphragm moves towards the pressure generating chamber, is caused by spring means.
When applying square wave pulses to the internal ear in cats with a patent cochlear aqueduct a pronounced rebound effect could be noted (Transmission of Square Wave Pressure Pulses through the Perilymphatic Fluids in Cats, B. Densert et al., Acta Otolaryngol., Stockholm 1986). In humans the situation might be similar. The pressure changes in the internal ear caused by the application of square wave pulses according to methods disclosed in the prior art thus could lead to results substantially differing from what was endeavoured. This provides a possible explanation of the fact that, in spite of various apparatuses for the production and transmission of such air pressure pulses having been devised over the past fifteen years, none of them has been put into practical use at a commercial scale. This delay in the implementation of an interesting therapeutic principle seems to be due not only to these apparatuses having certain drawbacks from a constructional point of view, making them insufficiently adapted to the need of most out-patients, but also to methodological shortcomings in regard of how to vary the pressure during a treatment such as to make it applicable to a large group of patients.
OBJECTS OF THE INVENTION
The present invention seeks to overcome these drawbacks and problems, and to provide an improved apparatus for treating Ménière's disease and similar conditions.
Other objects of the invention will become apparent from the following short description of the invention and a preferred embodiment of it, as well as from the appended claims.
SUMMARY OF THE INVENTION
The present invention bases on the insight that the forced displacement of the diaphragm in both directions, that is, towards and away from the pressure generating chamber, carries with it a number of problems, and can be advantageously substituted by a forced movement towards the chamber and a passive movement away from the chamber. One drawback with the bi-directional forced movement is the marked deviation from linearity of the spring force; another is the substantial variation of spring force within a sample of coil springs of the same kind. The incremental spring force substantially increases with the distance of diaphragm's displacement from an idle position and translates into problems with the control of the device by the microprocessor. Another drawback with prior art devices is excess energy consumption caused by the need to work against an apparatus-inherent force in both directions of displacement.
According to the present invention is provided an apparatus for treatment of Ménière's disease by intermittently increasing, in an air (gas) pressure chamber being in communication with an outwardly sealed external ear volume bordering to the tympanic membrane, air (gas) pressure, the apparatus comprising a peripherally fixed flexible circular diaphragm forming a wall of the chamber and being displaceable (from an idle position) in the direction of the chamber, the apparatus further comprising actuating means for displacing the diaphragm in the direction of the chamber but essentially lacking means for displacing it in an opposite direction. The movement of the diaphragm away from the chamber thus is essentially caused by the air pressure built up in the chamber and cavities communicating with the chamber. By ‘essentially’ is meant that the generation of small resilient forces on displacement of the membrane (diaphragm) according to the invention towards the chamber in an open state is negligible in comparison with the resistance experienced in a corresponding displacement with the chamber in a closed state; in this context ‘closed state’ refers to the chamber being in communication with the the outwardly sealed external ear volume but not with the atmosphere, while ‘open state’ refers to the chamber being in communication with the outwardly sealed external ear volume and with the atmosphere, for instance by of an open valve.
By ‘negligible’ is meant that the force required to displace the diaphragm by a given distance, such as a distance of about 5 mm, towards the chamber with the chamber in a closed state is at least 5 times greater that the force required for a corresponding displacement with the chamber in an open state, preferably at least 10 times greater.
In other words, the design of the diaphragm should be adapted to avoid, up to the desired maximum displacement, the generation of substantial resilient forces. It is thus preferred for the diaphragm to be displaceable (from an idle, neutral position) towards the chamber essentially without being tensioned.
It is also important that combined mass of the displaceable elements of the apparatus of the invention, that is, the diaphragm and the elements coupled to the diaphragm to make it move towards the chamber, is kept as small as possible. This contributes to the apparatus of the invention saving energy in comparison with devices known in the art which is of advantage in particular for battery driven mobile apparatus.
Preferably the actuating means comprise linear electromagnetic displacement means.
According to a first preferred aspect of the invention the apparatus comprises one or several or: pressure sensing means for monitoring the gas pressure in the chamber; pressure equalising means for equalising the air pressure in the chamber with ambient air pressure; control means comprising a microprocessor, for controlling the displacement of the diaphragm and the pressure equalising means by signal input from the pressure sensing means.
It is preferred for the pressure equalising means to comprise valve means. It is preferred for the valve means to be in an open (equalising) position except during the generation of pulse trains. Particularly preferred are silent valve means working below a sound pressure level of 20 dB, in particular valve means provided with sealing faces comprising a resilient polymer. Also preferred is to control the pressure equalising means in a way such as to reduce valve noise, in particular by opening the valve slowly at the end of a pulse train and closing the valve slowly before the start of a pulse train, for example by making the opening and closing to comprise from about 0.5 seconds to 1.5 seconds, typically about one second, when going from the fully closed position to the fully opened position and vice-versa.
It is preferred for the diaphragm actuating means to comprise an elongate actuating member having an axis and being fixed to the diaphragm at its one end and, preferably at its
Engvall Daniel
Nilsson Anders
DeMille Danton D.
Medtronic Inc.
Ostrolenk Faber Gerb & Soffen, LLP
Thanh Quang D
LandOfFree
Apparatus for treatment of ménière's... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus for treatment of ménière's..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for treatment of ménière's... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3174424