GB2335743A

GB2335743A - Remote monitoring of biological sensing implant

Info

Publication number: GB2335743A
Application number: GB9806170A
Authority: GB
Inventors: David Eglise
Original assignee: Individual
Current assignee: Individual
Priority date: 1998-03-24
Filing date: 1998-03-24
Publication date: 1999-09-29
Also published as: GB9806170D0

Abstract

There is disclosed a method for measuring biological and physical conditions using a system comprising of a compatible sensor device which can be placed or implanted within other bio-physical environments and the said changes detected and the output measurement is communicated to a remote reader unit using wireless, contactless means.

Description

1 This invention relates to a remote monitoring system for biological and

physical conditions.

Social and economic pressures are exerting a very strong stimulus for medical diagnostic and pharmaceutical companies to reduce the costs of their medicines and yet, paradoxically, to bring new products to market more quickly but without incurring any greater risks to patients than are perceived to exist already. The increasing technical complexity and demands of the product development process is primarily in response to burgeoning Regulatory Authority requirements which has led to a steady increase in the time needed to bring a new product to market. This not only delays the time at which a return on the considerable investment may be realised. but it also effectively limits the return which can be made because of the erosion of the effective patent life.

If this situation is taken in conjunction with the fact that the number of New' Chemical Entities and Biologicals being launched on a world-wide marketplace is in decline there is clearly a need to develop effective products for accelerating drug development and for practising clinical medicine. Body sensors are used extensively in medicine but invariably require some form of external connection which are in turn connected to some form of measurement apparatus. This implies that patients have electrical wires andlor feeder tubes passing through the body wall attached to organs, fluids etc. in order to convey information to external equipment for analysis. In some cases patients or as in pre- dinical research, animals are in fact mobile and are required to provide this type of information over long periods of time, in situations which represent the subjects normal living environment. The collection of information under these circumstances can be extremely difficult, unfriendly and somewhat impractical.

This inevitably brings about the need for a method of reading carnal functions within the body in such a way that information can be communicated to an external reading devices without the need for wires or tubes. The use of an 2335743 2 implanted miniaturised radio frequency device, brought about by using coil-onchip technology connected to various using physical, enzymic or chemical sensors, which combined with the capability to recafibrate a sensor device without retrieving it from the patient or host, provides a technology system for addressing many of the issues associated with monitoring carnal functions for pre-dinical drug evaluation and clinical diagnostic treatments.

According to the present invention there is provided a passive RF microchip transponder device and sensor which can be (i) interrogated to read and process any information and (5) written to so to update information used for sensor calibration purposes when necessary (iii) provide energy for other components of the system (iv) implanted within animal/human tissue or be part of controlled biological, chemical or ersatz environments. This implies that information can be extracted from RF sensing device which is small enough to form part of the host itself, be implanted or be part of an suitable attachment i.e. remote sensing tag.

These devices can form part of actual packaging or objects and can be used to identify the host and in turn monitor conditions inside or outside the packaging wall which can be associated with the integrity of the host.

According to the present invention there is provided a RF monitoring system comprising of a RF microchip transducer connected to a sensor incorporated with or part of the host to be monitored and a portable interrogator which can be used to read out sensor data and in addition, writing information to the RF microchip transducer for re-calibration purposes and alike.

A specific embodiment of the invention will now be described by way of an example with reference to the accompanying drawing in which:- Figure 1 shows a system block diagram.

3 Figure 2 illustrates the use in a medical application Figure 3 shows the device assembly. Figure 4 illustrates alternative medical application Referring to the drawings the system comprises a RF microchip transponder and a bio-compatible enrobement attached to a suitable sensor using, for example, a bio-compatible cable, foil or similar means (not shown). In order to power up, write or read information from the transponder device, a small read/write probe is used to create a localised unmodulated RF energy field which when in range, allows an implanted transponder device to generate the necessary supply voltage for the RF device and the attached sensor assembly, although in certain circumstances where the sensor is continuously reading a bio-compatible power source will be used i.e. battery.

Once powered up, data transmissions take place to establish a protocol to either read or write e.g. read information/signals from the sensor or alternatively Mte information into the device for sensor set-up or recalibration procedures. Information can consist of, but not limited to, where applicable, calibration and offset parameters, equipment reference, equipment host details, timeldate, treatment.

The principal purpose of having information contained in the device is to allow various bio-chemical or chemical sensors to be compensated against ageing or cell contamination in the body which will facilitate accurate and reliable operation. The information contained in the implanted device can be read at anytime and changed to accommodate sensor degradation, doing away with the immediate need for removing the sensor from the host. This technique can be used for, but not limited to, internal and external biological sensing i.e. blood pressure, core body temperature, drug dosage and delivery, blood analysis [glucose (diabetes)], With this system, the user can non-invasively have L immediate and relevant information relating to a physical andlor bio- chemical condition being monitored.

This can be achieved by interrogating the RF transponder which can be implanted under the skin in tissue or alternatively behind a synthetic membrane, with a small hand held interrogator which provides sufficient energy to activate the transponder and sensor in described above. This type of precise, information will improve the reliability, accuracy and credibility of preclinical and clinical procedures and removes the need for wiring, tubes from the patient/animal which invariably provides a more patient friendly operation. In addition to checking and amending the information contained within the device, one can add additional text to record any comments, ongoing medical treatment, fast entry, time & date all of which can be down loaded to a database at a later time for additional checking and accountability purposes.

The interrogators include a display which is controlled by a software program to interpret the information received from the sensor(s). This information can be stored and related to a defined range of readings whereby the interrogator can compare and trend these readings and assess whether the condition of the patient is deteriorating or not. As a direct result of these events, the patient can contact his/her doctor for advice or treatment. This includes checking whether a patient is taking/folloWng a prescribed course of actions/drugs for long term reasons i.e. the information can be configured to provide a selection of features such as historic log which can be used to display trends and facilitate making appointments for further medical investigation.

In addition, the RF transponder device can be used as a non-invasive "micro" database attached to a host object or component whereby the programmed information can be edited/updated using a small hand held read/write probe interfaced to a small computer device and will function satisfactorily in the 7 S' presence of body tissue, fluids, moisture, dirt and other hostile conditions which has practical and economical advantages over the use of conventional marking or labelling. An alternative embodiment is to have a sensor partitioned in such a way that one node of the sensor is external whilst the other corresponding sensor node is connected to the RF transducer which together is implanted within a body or other side of a membrane. This is an important feature if the sensor is required to measuring specific light absorption in tissue andlor skin or fluids, gas etc. This arrangement allows for optical [light] sources to be generated externally and aimed at a small optical receiver under the skin which is powered separately by RF to provide power and communications for extracting received information from the receiver part of the sensor. This has an advantage of the light path being measured through a skin is shorter and hence more predicable than using alternative light reflection techniques when both parts of the sensor are external.

Claims

1, A remote passive RFAID diagnostic system comprising a miniature biocompatible RF transponder device directly connected to a remote biocompatible sensor which together or separately can be implanted within body tissue or other bic>-physical environments and be (i) read remotely i.e. through skin or synthetic membranes to retrieve information acquired from the sensor, and (ii) additionally provide power via RF means to power the sensor and ancillary circuit functions

2. A remote passive RFAD diagnostic system as claimed in Claim 1 wherein the device can be interrogated remotely at any time to enterlstore sensor offsetlcalibration parameters which may be required to compensate for sensor ageing or contamination thus eliminating degradation and performance of en vivo sensors and alike.

3, A remote passive RF diagnostic system as claimed in Claim 1 and Claim 2 wherein the RF microchip device can be used with a plethora of different sensors which can be installed as an integral component with specific objects [living or otherwise) and can be used to monitor several internal conditions from which the information can be read remotely by an external interrogator device as to register changes or modifications of the condition(s) being monitored.

A remote passive RF diagnostic system as claimed in Claim 1 and Claim 2 wherein the RF microchip device can be used with a sensor(s) which can work in conjunction with other energy source for measuring purposes whereby an implanted sensor can respond to an externally generated energy source and correspondingly translate the received energy into information which can be read remotely A remote passive RF diagnostic system as claimed in Claim 1 and Claim 2 wherein the RF microchip device can be used with a plethora of different sensors which can be installed as an integral component with specific objects [living or otherwise] and can be used to monitor several internal conditions from which the information can 7 be read remotely by an external interrogator device as to register changes or modifications of the condition(s) being monitored.

5, A remote programmable RF diagnostic system as claimed in Claim 1, Claim 2 or Claim 3 wherein the RF microchip device incorporates a small microprocessor element and a bio-compatible power source i.e. battery which can be used to continuously monitor and store events read by the sensors during certain times and over certain periods; the information being stored for later retrieval using a remote interrogator.

6. A remote programmable RF diagnostic system as claimed in Claim 1, Claim 2, Claim 3 and Claim 4 whereby the interrogators interpret the information received from the sensor(s) via the RF transponders to compare and trend previous readings and assess whether the condition of the patient is deteriorating or not and as a direct result of these events, provide advice so treatment can be obtained.

7. A remote RF diagnostic 1 monitoring system as claimed in Claim 1 or Claim 2 or Claim 3 or Claim 4 wherein the RF transducer and sensor are sufficiently small to be implanted within the body of animals, humans for the purpose of remote, non invasive monitoring of bodily conditions and the storing of generic data and subsequent modification details in the device which can be edited/updated when necessary.

8. A remote RF diagnostic monitoring system as claimed in Claim 2 or Claim 3 or Claim 4 wherein the information contained in the transponder's non-volatile memory can be assigned access rights whereby initial data can be stored in its memory, leaving space in the memory for follow-on data from sequential events andlor subsequent user activities.

9. A remote RF diagnostic monitoring system as claimed in Claim 2 or Claim 3 or Claim 4 or Claim 5 wherein there is provided a RF diagnostic system comprising of a passive RF transducer connected to a bio- compatible sensor incorporated with or part of the object to be monitored and a I? handheld read/write interrogator which can be interfaced with a portable computer device for reading and writing to the RF diagnostic system device.

1O.A remote programmable RF diagnostic / monitoring system substantially as described herein with reference to figures 1 to 3 of the accompanying drawings.