Abstract: A hearing actuator (10) for implantation in the middle ear of a user. The actuator comprises transducer means (for example a piezoelectric device) (12) for converting electrical input signals into mechanical vibrations, and attachment means (16) for attaching one end of the transducer means to a first part of the middle ear. The actuator also comprises contacting means (14) which extends from an opposite end of the transducer means such that a longitudinal axis of the contacting means is substantially parallel to a longitudinal axis of the transducer means. The contacting means is for contacting a second part of the middle ear (to which it may be attached), so as to transmit the mechanical vibrations of the transducer means thereto.

Abstract: An ossicular replacement prosthesis (ORP) (10) for coupling a first point to a second point in the middle ear of a patient, to replace all or part of the ossicular chain. The ORP includes a coupling having a variable configuration for accounting for pressure differentials. The coupling includes a fluid filled chamber (28, 14) having two relatively moveable portions (12, 22) for varying the configuration of the coupling. The coupling further includes unsealed portion constituting leak portion and flowpath portion for permitting displacement of the fluid (30). The relative movement of the relatively moveable portions is controlled by the movement of the fluid in said chamber. The chamber is configured to restrict the movement of the fluid such that relative movement of the moveable portions is permitted in response to quasi-static changes in pressure, and is substantially prevented in response to vibrational changes corresponding to sound frequencies.

Abstract: The present invention concerns an actuator for an implantable hearing aid for implantation into the human middle ear. The actuator comprises a substantially elongate piezoelectric component (34, 36) having first and second operating end faces (41, 43), said end faces extending substantially at right angles to the longitudinal axis of the piezoelectric component. Also there is provided a frame component comprising at least one flextensional amplifier element (32), the flextensional amplifier element being integral with and connecting first and second frame end portions (42, 44), the first and second frame end portions also extending substantially at right angles to longitudinal axis of the piezoelectric component when fitted thereto, whereby the first and second end portions are in contact with the piezoelectric component end faces.

Abstract: Coupling apparatus for coupling an implantable element to the round window membrane. The apparatus comprises engagement means in the form of a clip or a filler material for engaging the bone surface within the round window niche. This supports the apparatus in the region of the round window membrane.

Abstract: Coupling apparatus for coupling an implantable element to the round window membrane. The apparatus comprises engagement means in the form of a clip or a filler material for engaging the bone surface within the round window niche. This supports the apparatus in the region of the round window membrane.

Abstract: A hearing actuator (10) for implantation in the middle ear of a user. The actuator comprises transducer means (for example a piezoelectric device) (12) for converting electrical input signals into mechanical vibrations, and attachment means (16) for attaching one end of the transducer means to a first part of the middle ear. The actuator also comprises contacting means (14) which extends from an opposite end of the transducer means such that a longitudinal axis of the contacting means is substantially parallel to a longitudinal axis of the transducer means. The contacting means is for contacting a second part of the middle ear (to which it may be attached), so as to transmit the mechanical vibrations of the transducer means thereto.

Abstract: An ossicular replacement prosthesis (ORP) (10) for coupling a first point to a second point in the middle ear of a patient, to replace all or part of the ossicular chain. The ORP comprises a coupling having a variable configuration for accounting for pressure differentials, said coupling comprising a fluid filled chamber (28, 14) having two relatively moveable portions (12, 22) for varying the configuration of the coupling. The coupling comprises unsealed means constituting leak means and flowpath means for permitting displacement of the fluid (30). The relative movement of the relatively moveable portions is controlled by the movement of the fluid in said chamber. The chamber is configured to restrict the movement of the fluid such that relative movement of the moveable portions is permitted in response to quasi-static changes in pressure, and is substantially prevented in response to vibrational changes corresponding to sound frequencies.

Abstract: The present invention concerns an actuator for an implantable hearing aid for implantation into the human middle ear. The actuator comprises a substantially elongate piezoelectric component (34, 36) having first and second operating end faces (41, 43), said end faces extending substantially at right angles to the longitudinal axis of the piezoelectric component. Also there is provided a frame component comprising at least one flextensional amplifier element (32), the flextensional amplifier element being integral with and connecting first and second frame end portions (42, 44), the first and second frame end portions also extending substantially at right angles to longitudinal axis of the piezoelectric component when fitted thereto, whereby the first and second end portions are in contact with the piezoelectric component end faces.

Abstract: An apparatus and method for determining a property of a sample, derived from a response obtained from the sample after an electrical pulse has been applied to it. Blood cells are subjected to an electrical pulse, a response is obtained using data retrieval means and a Fourier Transform is applied to the response. As the pulse applied is of very short duration (ideally a Dirac pulse) the Fourier transform yields information across a very broad bandwidth, typically several MHz, and accordingly a wide range of frequency response data is obtained. Certain cellular defects can be deduced from the transformed data. A detector is provided to detect precisely the presence of a cell as it passes through a particular region of an oriface. This is then used to trigger the pulse at a precisely controlled instant. This reduces the effect of random dispersion and can be adapted to ignore noise peaks which inevitably occur.