Implantable Radio-Frequency Sensor

• US 20130231550A1
• Filed: 07/21/2011
• Published: 09/05/2013
• Est. Priority Date: 07/21/2010
• Status: Abandoned Application

• Current Assignee: ZOLL Medical Israel Limited (Asahi Kasei Corporation)
• Original Assignee: Kyma Medical Technologies Ltd. (Asahi Kasei Corporation)
• Inventors: Weinstein, Uriel, Bernstein, Assaf, Cohen, Eyal, Oppenheim, Dov, Mosesko, Moshe
• Application Number:
  US13/811,210
• Publication Number:
  US 20130231550A1
• Time in Patent Office: Days
• US Class Current: 600/407
• CPC Class Codes: A61B 1/313 for introducing through surgical openings, e.g. laparoscopes
• CPC Class Codes: A61B 17/3468 for implanting or removing devices, e.g. prostheses, implants, seeds, wires devices for implanting seeds A61M37/0069
• CPC Class Codes: A61B 2560/0219 of externally powered implanted units
• CPC Class Codes: A61B 2562/0214 Capacitive electrodes
• CPC Class Codes: A61B 2562/164 the sensor is mounted in or on a conformable substrate or carrier
• CPC Class Codes: A61B 5/0028 Body tissue as transmission medium, i.e. transmission systems where the medium is the human body
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/01 Measuring temperature of body parts ; Diagnostic temperature sensing, e.g. for malignant or inflamed tissue clinical contact thermometers G01K13/20
• CPC Class Codes: A61B 5/0205 Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/05 Detecting, measuring or recording for diagnosis by means of electric currents or magnetic fields; Measuring using microwaves or radio waves impedance plethysmography A61B5/0295; measuring movement of the entire body or parts thereof A61B5/11; detecting, measuring or recording bioelectric or biomagnetic signals of the body or parts thereof A61B5/24
• CPC Class Codes: A61B 5/0537 Measuring body composition by impedance, e.g. tissue hydration or fat content
• CPC Class Codes: A61B 5/0538 invasively, e.g. using a catheter
• CPC Class Codes: A61B 5/076 Permanent implantations telemetry using implanted circuitry A61B5/0031; implanted stimulators for therapy A61N1/3605, A61N1/362, A61N1/372
• CPC Class Codes: A61B 5/0809 by impedance pneumography
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/287 Holders for multiple electrodes, e.g. electrode catheters for electrophysiological study [EPS]
• CPC Class Codes: A61B 5/416 the spleen
• CPC Class Codes: A61B 5/4244 liver
• CPC Class Codes: A61B 5/4552 : Evaluating soft tissue within the mouth, e.g. gums or tongue
• CPC Class Codes: A61B 5/4875 : Hydration status, fluid retention of the body
• CPC Class Codes: A61B 5/6833 : Adhesive patches
• CPC Class Codes: A61B 5/686 : Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61B 5/72 : Signal processing specially adapted for physiological signals or for diagnostic purposes character recognition, recognising digital ink, document-oriented image-based pattern recognition G06V30/00; recognition or understanding of postal images G06V30/424
• CPC Class Codes: A61N 1/36521 : the parameter being derived from measurement of an electrical impedance
• CPC Class Codes: A61N 1/3702 : Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371
• CPC Class Codes: A61N 1/37229 : Shape or location of the implanted or external antenna
• CPC Class Codes: A61N 1/3756 : Casings with electrodes thereon, e.g. leadless stimulators

Abstract

Diagnostic apparatus (24) includes a sealed case (40), including a biocompatible material and configured for implantation within a body of a human subject (22). At least one antenna (42) is configured to be implanted in the body in proximity to a target tissue (28) and to receive radio frequency (RF) electromagnetic waves propagated through the target tissue and to output a signal in response to the received waves. Processing circuitry (44, 46), which is contained within the case, is coupled to receive and process the signal from the antenna so as to derive and output an indication of a characteristic of the target tissue

Claims

1. Diagnostic apparatus, comprising:

a sealed case, comprising a biocompatible material and configured for implantation within a body of a human subject;

at least one antenna, which is configured to be implanted in the body in proximity to a target tissue and to receive radio frequency (RF) electromagnetic waves propagated through the target tissue and to output a signal in response to the received waves; and

processing circuitry, which is contained within the case and is coupled to receive and process the signal from the antenna so as to derive and output an indication of a characteristic of the target tissue.

2. The apparatus according to claim 1, wherein the at least one antenna is configured to transmit the waves into the body and to receive the transmitted waves following propagation of the waves through the target tissue.

3. The apparatus according to claim 2, wherein the at least one antenna is configured to receive the waves after reflection of the waves from a tissue in the body, and wherein the processing circuitry is configured to detect a modulation of the reflection due to at least one of a heartbeat and a respiratory motion of the subject.

4. The apparatus according to claim 3, wherein the modulation comprises a cyclical variation due to the heartbeat.

5. The apparatus according to claim 2, and comprising a reflector configured for implantation in the body in a location across the target tissue from the case containing the at least one antenna, wherein the reflector serves as the structure for reflecting the waves toward the at least one antenna.

6. The apparatus according to claim 5, wherein the reflector is a part of an implanted cardiac device (ICD) that is implanted in the body.

7. The apparatus according to claim 1, and comprising a transmitter, which is configured to be implanted in the body in a location across the target tissue from the case containing the at least one antenna and to transmit the waves through the target tissue.

8. The apparatus according to claim 1, wherein the processing circuitry is configured to process the signal so as to derive a measure of a fluid content of the target tissue.

9. The apparatus according to claim 8, wherein the case is configured for implantation in a thorax, and wherein the target tissue is lung tissue.

10. The apparatus according to claim 8, wherein the target tissue is spleen, liver, tongue or palate tissue.

11. The apparatus according to claim 1, wherein the indication comprises a time trend of the characteristic of the target tissue.

12. The apparatus according to claim 1, wherein the at least one antenna comprises a plurality of antennas.

13. The apparatus according to claim 12, wherein the processing circuitry is configured to drive the antennas in a multi-static mode so as to spatially resolve the characteristic of the target tissue.

14. The apparatus according to claim 1, wherein the at least one antenna is contained inside the case.

15. The apparatus according to claim 14, wherein the at least one antenna comprises a trace printed on a substrate, and wherein the case comprises a window, and the antenna is configured to receive the waves through the window.

16. The apparatus according to claim 15, wherein the substrate is sealed to the case by brazing.

17. The apparatus according to claim 1, wherein the at least one antenna is located partially outside the case and is connected to the processing circuitry via a sealed brazing to the case.

18. The apparatus according to claim 1, wherein the at least one antenna comprises a trace printed on a substrate and a backlobe suppression structure behind the trace.

19. The apparatus according to claim 18, wherein the backlobe suppression structure is selected from a group of structures consisting of an air cavity and an electromagnetic bandgap (EBG) backing.

20. The apparatus according to claim 1, wherein the at least one antenna is selected from a group of antenna types consisting of a spiral antenna, a bowtie antenna, an elliptic bowtie antenna, and a slotted antenna.

21-48. -48. (canceled)