Physics of Sound & Vibration

          An Inter-Disciplinary Resource Website to Effects on Human Electrodynamic Physiology

 

                                     www.uncg.edu/~t_hunter/sound.html

 Main Menu

Site Map

 

Patent No. 6164284  System of implantable devices for monitoring and/or affecting body parameters (Schulman, et al., Dec 26, 2000)

Abstract

A system for monitoring and/or affecting parameters of a patient's body and more particularly to such a system comprised of a system control unit (SCU) and one or more other devices, preferably battery-powered, implanted in the patient's body, i.e., within the envelope defined by the patient's skin. Each such implanted device is configured to be monitored and/or controlled by the SCU via a wireless communication channel. In accordance with the invention, the SCU comprises a programmable unit capable of (1) transmitting commands to at least some of a plurality of implanted devices and (2) receiving data signal from at least some of those implanted devices. In accordance with a preferred embodiment, the system operates in closed loop fashion whereby the commands transmitted by the SCU are dependent, in part, on the content of the data signals received by the SCU. In accordance with the invention, a preferred SCU is similarly implemented as a device capable of being implanted beneath a patient's skin, preferably having an axial dimension of less than 60 mm and a lateral dimension of less than 6 mm. Wireless communication between the SCU and the implanted devices is preferably implemented via a modulated sound signal, AC magnetic field, RF signal, or electric conduction.

 

Notes:

BACKGROUND OF THE INVENTION

The present invention relates to systems for monitoring and/or affecting parameters of a patient's body for the purpose of medical diagnosis and/or treatment. More particularly, systems in accordance with the invention are characterized by a plurality of devices, preferably battery-powered, configured for implanting within a patient's body, each device being configured to sense a body parameter, e.g., temperature, O.sub.2 content, physical position, etc., and/or to affect a parameter, e.g., via nerve stimulation.

Applicants' parent application No. 09/030,106 entitled "Battery Powered Patient Implantable Device", incorporated herein by reference, describes devices configured for implantation within a patient's body, i.e., beneath a patient's skin, for performing various functions including: (1) stimulation of body tissue, (2) sensing of body parameters, and (3) communicating between implanted devices and devices external to a patient's body.

SUMMARY OF THE INVENTION

The present invention is directed to a system for monitoring and/or affecting parameters of a patient's body and more particularly to such a system comprised of a system control unit (SCU) and one or more devices implanted in the patient's body, i.e., within the envelope defined by the patient's skin. Each said implanted device is configured to be monitored and/or controlled by the SCU via a wireless communication channel.

In accordance with the invention, the SCU comprises a programmable unit capable of (1) transmitting commands to at least some of a plurality of implanted devices and (2) receiving data signals from at least some of those implanted devices. In accordance with a preferred embodiment, the system operates in closed loop fashion whereby the commands transmitted by the SCU are dependent, in part, on the content of the data signals received by the SCU.

In accordance with a preferred embodiment, each implanted device is configured similarly to the devices described in Applicants' parent application 09/030,106 and typically comprises a sealed housing suitable for injection into the patient's body. Each housing preferably contains a power source having a capacity of at least 1 microwatt-hour, preferably a rechargeable battery, and power consuming circuitry preferably including a data signal transmitter and receiver and sensor/stimulator circuitry for driving an input/output transducer.

In accordance with a significant aspect of the preferred embodiment, a preferred SCU is also implemented as a device capable of being injected into the patient's body. Wireless communication between the SCU and the other implanted devices can be implemented in various ways, e.g., via a modulated sound signal, AC magnetic field, RF signal, or electrical conduction.

In accordance with a further aspect of the invention, the SCU is remotely programmable, e.g., via wireless means, to interact with the implanted devices according to a treatment regimen. In accordance with a preferred embodiment, the SCU is preferably powered via an internal power source, e.g., a rechargeable battery. Accordingly, an SCU combined with one or more battery-powered implantable devices, such as those described in the parent application, form a self-sufficient system for treating a patient.

In accordance with a preferred embodiment, the SCU and other implanted devices are implemented substantially identically, being comprised of a sealed housing configured to be injected into the patient's body. Each housing contains sensor/stimulator circuitry for driving an input/output transducer, e.g., an electrode, to enable it to additionally operate as a sensor and/or stimulator.

Alternatively, the SCU could be implemented as an implantable but non-injectable housing which would permit it to be physically larger enabling it to accommodate larger, higher capacity components, e.g., battery, microcontroller, etc. As a further alternative, the SCU could be implemented in a housing configured for carrying on the patient's body outside of the skin defined envelope, e.g., in a wrist band.

In accordance with the invention, the commands transmitted by the SCU can be used to remotely configure the operation of the other implanted devices and/or to interrogate the status of those devices. For example, various operating parameters, e.g., the pulse frequency, pulse width, trigger delays, etc., of each implanted device can be controlled or specified in one or more commands addressably transmitted to the device. Similarly, the sensitivity of the sensor circuitry and/or the interrogation of a sensed parameter, e.g., battery status, can be remotely specified by the SCU.

In accordance with a significant feature of the preferred embodiment, the SCU and/or each implantable device includes a programmable memory for storing a set of default parameters. In the event of power loss, SCU failure, or any other catastrophic occurrence, all devices default to the safe harbor default parameters. The default parameters can be programmed differently depending upon the condition being treated. In accordance with a further feature, the system includes a switch preferably actuatable by an external DC magnetic field, for resetting the system to its default parameters.

In an exemplary use of a system in accordance with the present invention, a patient with nerve damage can have a damaged nerve "replaced" by an implanted SCU and one or more implanted sensors and stimulators, each of which contains its own internal power source. In this exemplary system, the SCU would monitor a first implanted sensor for a signal originating from the patient's brain and responsively transmit command signals to one or more stimulators implanted past the point of nerve damage. Furthermore, the SCU could monitor additional sensors to determine variations in body parameters and, in a closed loop manner, react to control the command signals to achieve the desired treatment regimen.

---------------------------------------------------------------

While the invention herein disclosed has been described by means of specific embodiments and applications thereof, numerous modifications and variations could be made thereto by those skilled in the art without departing from the scope of the invention set forth in the claims. For example, a system including multiple SCUs, e.g., one external and one internal, is considered to be within the scope of the present invention. Additionally, while the use of a single communication channel for communication between one or more SCUs and the other implanted devices has been described, a system implemented using multiple communication channels, e.g., a first sonic channel at a first carrier frequency and a second sonic channel at a second carrier frequency, is also considered to be within the scope of the present invention.