Dymedix Corporation

Eden Tec Corporation

Nt International, Inc.

Alphamed, Inc.

Peter Stasz

Bruce R Bowman

Charles Bille

Reinhold Henke

Gerald R Cucci

Evan Stuart Johnston

David Mathews

Sheri L Brewer

Paul E Bjork

Alan Bradley Jones

William H Ham

David Gust

Joseph D Vallie

Michael W Barr

Terry Hudrlik

Thomas H Zymowski

Allen J Pickard

Evan S Johnston

Circuits for rendering piezo-based respiratory belts compatible with polysomnograph (PSG) machines designed for use with respiratory induction belts (RIPs) comprise an instrumentation amplifier adapted to be connected to a piezoelectric transducer and providing an AC output signal to a low-pass filter. In a first embodiment, the low-pass filter output is applied to an input of a microcontroller's A to D converter and the resulting digitized samples are used to vary the resistance of a digital potentiometer whose wiper terminal is coupled in series with an inductor so as to emulate the presence of a RIP belt to the PSG machine. In a second embodiment, the low-pass filter output is used to drive the primary of a transformer so as to vary the permeability of the transformer's ferrite core in a way that emulates the performance of a RIP belt to the PSG.

Apparatus and method for adapting a piezoelectric respiratory sensing belt to a respiratory inductance plethysmography polysomnograph

This document discusses, among other things, a system and method for anti-habituating sleep therapy using a closed loop neuromodulator. A first sleep disorder event can be detected using first activity information, and a first series of stimuli can be provided, in response to the first sleep disorder event, using a set of stimulus parameters. A habituation event can be detected and anti-habituation stimulation parameter can be adjusted to avoid patient habituation to the stimuli.

Anti-habituating sleep therapy for a closed loop neuromodulator

This document discusses, among other things, a system and method for generating a sleep therapy stimulus waveform for a patient. Stimulus sequence information can be selected from a sequence memory array, and stimulus sequence information can be received from the sequence memory array at a stimulus generator selector. A generator select signal can be provided to a stimulus generator of a closed loop neuromodulator using the stimulus sequence information and a stimulus duration signal, wherein the generator select signal can include stimulus type information related to stimulus pulses generated using the closed loop neuromodulator.

Stimulus sequencer for a closed loop neuromodulator

A sensor for use with a polysomnograph in a sleep lab setting is made reusable by laminating a PVDF film and associated lead contacts within a flexible, moisture-impervious plastic envelope that is hermetically sealed about its periphery. Lead terminals within the envelope are adhered to the metalized surfaces of the PVDP film using a conductive adhesive which inhibits dislodgement of the leads from the sensor even with rough handling and cleaning.

Reusable snore/air flow sensor

An adapter for interfacing a pyro/piezo sensor to a polysomnograph machine comprises a differential input amplifier coupled to receive the raw transducer signals from a PVDF film transducer to provide a requisite gain while rejecting common mode noise. The resulting amplified signal is filtered to separate the pyro signal from the piezo signal and the piezo signal is further applied to half-wave rectifier stages that function to remove baseline noise from the piezo signal before its being applied to a microphone channel of an existing PSG machine.

Signal processing circuit for pyro/piezo transducer

A snore sensor incorporating a piezoelectric polyvinylidene fluoride (PVDF) film material adapted to be adhered to the skin of a sleeping patient on the patient's throat for detecting mechanical vibrations due to snoring. The PVDF film has a layer of metallization on opposed major surfaces thereof which are insulated from one another by the PVDF material itself and elongated electrical leads individually connect to the metallization layers. One major surface of the film layer is covered by a layer of adhesive tape and the opposite major surface with its metallization is underlayed by a thin layer of plastic film having an adhesive on opposed surfaces thereof. The adhesive on one side of the plastic film layer adheres it to the PVDF film while the adhesive on the opposed major surface of the plastic film is used to adhere the device to the patient's skin.

Snore sensor

A combination thermal and vibration sensor for use in sleep monitoring equipment comprises a thin film of a plastic exhibiting both pyroelectric and piezoelectric properties. By providing a layer of foam material totally covering one major surface of the plastic film layer, it is found that the thermal mass of the sensor is changed to the point where the pyroelectric signal can more readily be isolated from the piezoelectric signal using conventional signal processing techniques.

Pyro/piezo sensor

A combination thermal and vibration sensor for use in sleep monitoring equipment comprises a thin film of plastic exhibiting both pyroelectric and piezoelectric properties. By providing a layer of foam material covering only a predetermined portion of one major surface of the film layer, it is found that the thermal mass of the sensor is changed to the point where the pyroelectric signal can be more readily isolated from the piezoelectric signal using conventional signal processing techniques. Because the layer of foam material is not present on a remaining portion of the piezo/pyro film, the signal output due to the film's piezoelectric properties is not unduly dampened and attenuated.

Pyro/piezo sensor with enhanced sound response

Electronic temperature/pressure transducer

A plurality of flow sensors are fabricated on a single substrate. The substrate is laid out to provide the proper physical relationship of the individual sensors. The resulting multiple sensor structure may be effectively used as a respiration detector by positioning a different sensor element at each of the airflow orifices (i.e., two nostrils and mouth) of a patient. In the preferred embodiment, the sensors are thermoresistive elements, which are screened on the substrate using conductive ink. The change in temperature of the air flow in relation to the ambient at each orifice provides an indication of the flow and may be used to determine the extent of the flow. The substrate is packaged in a single piece adhesive strip which provides ease of proper attachment by the patient.

Method of making a respiration sensor

A DC-to-DC converter suitable for use in light-powered electronic systems. The DC electrical output from a solar cell is stepped-up in a chopper-type inverter that is driven by a gated oscillator. The output from the inverter is then rectified and is adapted to be applied to a load through a series connected switch whose on/off state is determined by the output from a voltage regulator. Connected between the rectifier and the series switch are energy storage capacitors which become charged when the series switch is open and which provide energy to the load when the series switch is closed. Feedback from the regulator circuitry controls the on/off state of the gated oscillator and, therefore, the energy delivered by the inverter. Further circuitry is provided for signaling a light transmitting device that the fiber-optic link delivering energy to the photo cell is intact.

Low level, high efficiency DC/DC converter

An apparatus for and method of monitoring respiration of a patient using impedance changes of the body to indicate respiration events. The impedance changes are measured by applying a carrier signal across the thorax of the patient. The carrier is periodically interrupted to produce a quiet period. A first level detector assumes the presence of EMI if the signal present during the quiet period exceeds a predetermined threshold. A second level detector senses the presence of substantial high frequency EMI. At initial power up, a third level detector checks for presence of signal before the carrier drive is applied. A fourth test circuit checks for the hang up of the differential amplification circuit.

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Saint Paul, MN, United States of America

Peter Stasz