Abstract: An implantable device such as a microphone that may be subcutaneously positioned in surrounding soft tissue. The implantable device may include a hermetically-sealed housing and a diaphragm that forms a portion of an outside surface of the housing. The microphone has a density that is no more than 110% of a density of the surrounding soft tissue. In one arrangement, the device may move in at least substantial unison with the surrounding soft tissue in response to a pressure or compression wave propagating through the soft tissue and being received at the device. In another arrangement, the device may include a filler that may be operable to alter the density of the device.

Abstract: An output stage for an auditory neurostimulation electrode and related system arrangements and methods are provided. The output stage is operable to effect a plurality of stimulation and discharge intervals, and includes a stimulation channel and a discharge channel coupled to the electrode, wherein a stimulation current and a discharge current may flow therethrough during the corresponding stimulation intervals and discharge intervals. The output stage also includes a controller that is operable to selectively control the flow of current through the stimulation channel and the discharge channel during the stimulation and discharge intervals. Further, one of the stimulation channel and the discharge channel couples the electrode to a single voltage supply, and the other of the stimulation channel and the discharge channel couples the electrode to a reference potential node.

Abstract: A system for reducing subcutaneous migration of an implantable device or housing relative to surrounding soft tissue. For instance, the implantable housing may support a microphone diaphragm. The system includes at least one securement member having at least one aperture extending therethrough that may selectively receive one of a soft tissue securement device (e.g., soft tissue suture) and soft tissue growth therethrough. The securement member is at least one of interconnected to and disposable over at least a portion of the housing and at least one of extends away from and is selectively extendable away from a periphery of the housing. In one arrangement, at least one mesh member may be optionally included with the system that may allow for tissue growth to enhance securement of the implanted device relative to the soft tissue.

Abstract: An implantable neurostimulation electrode interface and related system arrangements and methods are provided. The implantable interface may include at least a first stimulation signal channel for receiving a first electrode stimulation signal and a plurality of electrode signal channels electrically interconnected or interconnectable to a plurality of electrodes for neurostimulation. The interface may further include a router electrically interconnected to the first stimulation signal channel and to the plurality of electrode signal channels. The router is controllable to directly route the first electrode stimulation signal to different first successive sets of one or more of the plurality of electrode signal channels. The router may be adapted for routing the first electrode stimulation signal as an electrical current signal, without modification of the signal. Stimulation signal generation componentry and power source componentry may be located remotely from the implantable interface.

Abstract: An improved implantable hearing instrument and associated method utilize a transducer to mechanically stimulate a patient's cochlea (e.g. via the round window or oval window) in response to a first electrical drive signal, and a supply electrode to electrically stimulate the patient's cochlea in response to a second drive signal. The first and second drive signals may be provided to affect mechanical stimulation across a first predetermined frequency range and electrical stimulation across a second predetermined frequency range, respectively, wherein the predetermined frequency ranges are at least partially non-overlapping. In one embodiment an electromechanical transducer, having the supply member supportably interconnect thereto, may be selectively positioned via a mounting member fixedly interconnected to a patient's skull. The supply electrode may define a distal tip that is supportably interconnected to a vibratory member of the electromechanical transducer.

Abstract: Methods for assessing a position of an actuator of an implantable hearing aid transducer relative to an auditory component of a patient. According to one aspect of the invention, an implantable hearing aid transducer is located in proximity to the auditory component of the patient. A test signal is provided to the patient to stimulate the auditory component and generate an acoustic response in the ear canal of the patient. The acoustic response is detected and utilized to assess the position of the actuator of the transducer relative to the auditory component.

Abstract: An implantable hearing instrument is provided that reduces the response to unnaturally high vibrations (e.g., due to a patient's own voice), without necessarily or substantially affecting the response to desired signals. The implantable hearing instrument system is operative to selectively alter/lower the gain of signals that have a magnitude above a predetermined threshold. Signals having unnaturally large amplitudes (e.g., due to a patient's own voice) are amplified less than desired signals, so that a patient may experience a more representative sound.

Abstract: The invention is directed to an implanted microphone having reduced sensitivity to vibration. In this regard, the microphone differentiates between the desirable and undesirable vibration by utilizing at least one motion sensor to produce a motion signal when an implanted microphone is in motion. This motion signal is used to yield a microphone output signal that is less vibration sensitive. In a first arrangement, the motion signal may be processed with an output of the implantable microphone transducer to provide an audio signal that is less vibration-sensitive than the microphone output alone. In another arrangement, the motion signal may be utilized to actuate at least one actuator. Such an actuator may be capable of applying a force to move the implantable microphone or an implant capsule so as to reduce movement of a microphone diaphragm relative to the skin of a patient which covers the microphone diaphragm.

Abstract: An implantable microphone comprises a hermetically-sealed, enclosed volume and an electret member and back plate disposed with a space therebetween and capacitively coupleable to provide an output signal indicative of acoustic signals incident upon at least one of the electret member and back plate. The back plate may be disposed to define a peripheral portion of the enclosed volume, e.g., the back plate may be defined as part of a flexible diaphragm that receives external acoustic signals. Vents may be provided to fluidly interconnect first and second portions of the enclosed volume that are located on first and second sides of the electret member. In another embodiment, the electret member may be flexible and spaced relative to a flexible outer diaphragm.

Abstract: The invention is directed to an implanted microphone having reduced sensitivity to vibration. In this regard, the microphone differentiates between the desirable and undesirable vibration by utilizing at least one motion sensor to produce a motion signal when an implanted microphone is in motion. This motion signal is used to yield a microphone output signal that is less vibration sensitive. In a first arrangement, the motion signal may be processed with an output of the implantable microphone transducer to provide an audio signal that is less vibration-sensitive than the microphone output alone. Specifically, the motion signal may be scaled to match the motion component of the microphone output such that upon removal of the motion signal from the microphone output, the remaining signal is an acoustic signal.

Abstract: An implantable microphone is disclosed having an external diaphragm and housing that forming chamber capable of being pressurized by deformational movement of the diaphragm induced by pressure waves (e.g., acoustic signals) propagating through overlying tissue. The chamber is shaped such that the volume of the chamber upon deflection of the diaphragm is reduced compared to a static volume of the chamber (i.e., volume of the chamber with no diaphragm deflection). As a result, the change in pressure within the chamber for a given diaphragm displacement is greater than it would be within a chamber having a cylindrical volume, leading to greater microphone sensitivity. In one arrangement, the chamber is shaped such that it is deeper at its center than at its edges, for example, to form a conical or paraboloidal volume.

Abstract: A variable reluctance motor is provided having a linear relationship between an input current and an output force. According to one aspect of the invention, the motor comprises a stator, an armature, and at least one magnetic member to provide a biasing force on the armature. According to this characterization, the motor also includes a drive coil to generate an electromagnetic field in response to a current input. The electromagnetic field, in turn, moves the armature relative to the stator during motor operation.

Abstract: A method for reducing oscillation of a feedback signal in a hearing aid and hearing aid configured according to the present method is provided. The method includes the steps of determining the phase of the feedback signal over a feedback path of the hearing aid and shifting only the phase of the feedback signal a predetermined amount, without modification of other signal characteristics, to achieve a non-zero net phase of the feedback signal over the feedback path such that oscillation of the signal is prevented. In one embodiment of the present method, the step of determining the phase may be performed at the time of fitting of the hearing aid to a patient. In another embodiment of the present method, the method includes the step of periodically determining the phase of the feedback signal over the feedback path such that the phase shifting may be performed based on the periodically determined phase.

Abstract: A noninvasive method and system are provided for assessing the performance of implanted actuators of semi or fully-implantable hearing aid systems. The invention utilizes an externally positioned measurement device to obtain a test measure of the electrical signal passing through an implanted actuator when driven by a test signal of predetermined characteristics. In one embodiment, the measurement device may comprise a pair of coils for measuring the magnetic field generated by an implanted actuator utilized to simulate the middle ear of a patient. The magnetic field strength is directly related to the amount of current passing through the actuator. In turn, such current is inversely related to the electrical impedance present at the implanted actuator. Such electrical impedance is directly related to the mechanical impedance present at the interface between the implanted actuator and middle ear of a patient.

Abstract: A retention apparatus for a semi-implantable hearing aid. In one embodiment, the retention apparatus includes a first surface and a second surface. One of the first and second surfaces includes a first portion and a second portion having a rounded transition therebetween for interfacing with a patient's skin. The rounded transition of the interfacing surface of the retention apparatus functions to distribute pressure resulting from the mutual magnetic attraction between an externally located magnet and an implanted magnet to permit increased magnetic forces therebetween and maintenance of a desired separation between an external coil and implanted coil.

Abstract: Provided herein are systems and methods where an implantable microphone of an implantable hearing system is positioned at a location spaced from the surface of the patient's skull. More specifically, the microphone is mounted to soft tissue of the patient to at least partially isolate the microphone from skull-borne vibrations. Accordingly, by utilizing a soft tissue mount, the microphone may be made more sensitive to ambient sounds with reduced concern to amplification of non-ambient vibrations caused by skull-borne vibrations including, for example, transducer feedback, talking and/or chewing. The system will further include an auditory stimulation device that is located proximate to the skull of the patient and which is operative to stimulate an auditory component of the patient in accordance with an output signal generated by the microphone. A subcutaneously routed signal wire may extend between the implanted microphone and the auditory stimulation device.

Abstract: An improved apparatus and method is provided for supportably mounting an implantable hearing aid device to a patient's skull. The apparatus includes a support member adapted for supporting a hearing aid device and a plurality of mounting legs extending laterally from the support member in differing directions. The apparatus further includes a mechanism for use in conforming the mounting legs to the topology of a patient's skull. In one arrangement, the mechanism includes a plurality of guide legs having a reduced yield strength in comparison to the mounting legs. The reduced yield strength guide legs may be more readily conformed to the topology of the patient's skull to provide a mounting leg profile. Accordingly, the mounting legs may be deformed to match the profile of the guide legs such that a conformal fit between the apparatus and the patient's skull may be achieved.

Abstract: Apparatus and methods are provided for maintaining a desired centered relationship between a vibratory actuator of an implantable hearing aid transducer and an auditory component post-implantation. In certain embodiments, at least two guide members may extend beyond a distal end of a vibratory actuator for positioning on opposing sides of an auditory component. The guide arms may be employed to restrict post-implantation auditory component movement, and additionally or alternatively, to apply a spring-loading force against an auditory component to reposition and thereby center such auditory component in the event of post-implantation auditory component movement. In certain embodiments, a distal end may be provided on a vibratory actuator, wherein the distal end has a plurality of differently-shaped concave surfaces. A selected one of the different concave surfaces may be positioned for contact engagement with an auditory component to optimize surface engagement.

Abstract: A hearing aid transducer that includes an actuator advanceable relative to the transducer to couple with a middle ear component. In one aspect of the invention, the actuator is a separate structure from the transducer that is insertable into an aperture defined between a first and second end of the transducer. This permits separate connection of the actuator to the middle ear component and the transducer to improve coupling of the transducer to the middle ear component, e.g., minimizing loads on the middle ear component.

Abstract: A transducer mounting system including a retention apparatus to provide an efficient detachable interconnection between a pivotable member and the mounting system. According. to one aspect, the retention apparatus is configured to travel along a predetermined path between an unlocked position and unlocked position to secure a transducer in a desired orientation relative to an auditory component. According to this aspect, the retention apparatus may include a compressible member to frictionally capture and positionally fix the pivotable member relative to the mounting system.