Method and system for monitoring thoracic tissue fluid

• US 10,561,336 B2
• Filed: 09/04/2008
• Issued: 02/18/2020
• Est. Priority Date: 09/05/2007
• Status: Active Grant

• Current Assignee: Sensible Medical Innovations Ltd.
• Original Assignee: Sensible Medical Innovations Ltd.
• Inventors: Rappaport, Dan, Mizrahi, Nadav, Bergida, Shlomi, Saroka, Amir, Ronen, Amir, Kochba, Ilan
• Primary Examiner(s): Brutus, Joel F
• Application Number:
  US12/676,381
• Publication Number:
  US 20100256462A1
• Time in Patent Office: 4,184 Days
• Field of Search: 600407, 600409, 600410
• CPC Class Codes: A61B 5/00 Measuring for diagnostic purposes radiation diagnosis A61B6/00; diagnosis by ultrasonic, sonic or infrasonic waves A61B8/00; Identification of persons
• 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 5/7203 for noise prevention, reduction or removal
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: A61B 5/7264 Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00
• CPC Class Codes: A61B 5/7275 Determining trends in physiological measurement data; Predicting development of a medical condition based on physiological measurements, e.g. determining a risk factor

Abstract

A method for monitoring thoracic tissue. The method comprises intercepting reflections of electromagnetic (EM) radiation reflected from thoracic tissue of a patient in radiation sessions during a period of at least 24 hours, detecting a change of a dielectric coefficient of the thoracic tissue by analyzing respective the reflections, and outputting a notification indicating the change. The reflections are changed as an outcome of thoracic movements which occur during the period.

Claims

1. A method for determining a pulmonary fluid content level in at least one thoracic tissue using at least one hardware processor and at least one antenna element, comprising:

radiating and intercepting, using at least one antenna element, radio frequency (RF) radiation at a range of 0.3 gigahertz (GHZ) to 20 GHZ to and from the at least one thoracic tissue of a patient in each of a plurality of radiation sessions;

identifying a differential signal from a difference between RF signals extracted from said RF radiation during one of said plurality of radiation sessions;

using at least one hardware processor to extract at least one feature from the differential signal, said at least one feature is selected from a group consisting a phase and an amplitude of the differential signal;

detecting a dielectric related property of the at least one thoracic tissue according to said at least one feature;

determining a pulmonary fluid content level in said at least one thoracic tissue according to said dielectric related property; and

outputting a notification based on said pulmonary fluid content level.

2. The method of claim 1, wherein at least some of said intercepting is performed when said patient is ambulatory.

3. The method of claim 1, wherein said dielectric related property is detected by identifying a segment representing said at least one thoracic tissue, and detecting said dielectric related property according to said segment.

4. The method of claim 3, wherein said dielectric related property is detected by using a predefined chest wall model for identifying said segment.

5. The method of claim 4, further comprising adjusting said predefined chest wall model according to at least one of medical information, a predefined cycle, and imaging data related to said patient.

6. The method of claim 1, wherein said determining comprises identifying a breathing cycle of said patient.

7. The method of claim 1, further comprising identifying a posture of said patient;

wherein said determining is performed with respect to the effect of said posture on said dielectric related property.

8. The method of claim 1, further comprising identifying an activity level, said determining being performed with respect to the effect of said activity level on a dielectric related property of the at least one thoracic tissue.

9. The method of claim 1, further comprising identifying a pattern of a change in said pulmonary fluid content, said pattern of a change being indicative of at least one of a pathologic pattern, wherein said notification is configured for indicating said at least one pathologic pattern.

10. The method of claim 9, wherein said at least one pathologic pattern is of a member selected from a group consisting of:

a degenerative process, acute respiratory distress syndrome (ARDS), congestive heart failure (CHF), trauma, an atelectasis, a post-operative atelectasis, a postoperative process, an osculated bronchus, a pulmonary inflammation progress, a pulmonary blood accumulation, an infectious causes, an inhaled toxins, a circulating exogenous toxins, a vasoactive substances, a disseminated intravascular coagulopathy (DIC), a immunologic processes reactions, a uremia, a post drowning lung water level, a pulmonary venous thrombosis, a stenosis, a veno-occlusive disease, a hypoalbuminemia, a lymphatic insufficiency, a high altitude pulmonary edema (HAPE), a neurogenic pulmonary edema, a drug overdose, a pulmonary embolism, an eclampsia, a postcardioversion, a postanesthetic, a postextubation, and post-cardiopulmonary bypass.

11. The method of claim 1, further comprising monitoring a biological parameter of said patient using a medical sensor, said determining being performed according to a combination of data based on said RF radiation and said biological parameter.

12. The method of claim 11, wherein said medical sensor is selected from a group consisting of an electrocardiogram (ECG), an electromyogram (EMG), an ultrasound transducer, a pulse oximeter, a blood pressure sensor, coagulometer, and optical blood saturation detector.

13. The method of claim 1, wherein further comprising identifying a current position of said at least one antenna element with respect to said at least one thoracic tissue;

wherein determining is performed with respect to the effect of said current position on said dielectric related property.

14. The method of claim 1, wherein said dielectric related property is indicative of at least one tissue transition.

15. The method of claim 1, further comprising identifying a breathing cycle of said patient and modulating said RF radiation according to said breathing cycle.

16. The method of claim 1, wherein said determining comprises identifying a buildup of thoracic tissue fluid level in a pathological pace according to an analysis of said dielectric related property;

wherein said notification is indicative of said buildup.

17. The method of claim 1, wherein said buildup reflects a trend of said thoracic tissue fluid level during said period of at least 24 hours.

18. The method of claim 1, wherein said difference is induced by a cyclic physiological process selected from a group consisting of a breathing cycle and a pace of heart beats.

19. A monitoring apparatus configured to determine a pulmonary fluid content level in at least one thoracic tissue using at least one hardware processor and at least one antenna element, said monitoring apparatus comprises:

a probe having at least one antenna element to radiate and intercept at least one radio frequency (RF) radiation at a range of 0.3 gigahertz (GHZ) to 20 GHZ to and from at least one thoracic tissue of a patient;

at least one hardware processor adapted to;

identify a differential signal from a difference between signals extracted from said RF radiation,

extract at least one feature from the differential signal, said at least one feature is are selected from a group consisting a phase and an amplitude extracted from said differential signal,

detect a dielectric related property of at least one thoracic tissue according to said at least one feature, and

determine a pulmonary fluid content level in said at least one thoracic tissue according to said dielectric related property;

wherein said probe and said at least one hardware processor are configured for respectively performing said interception and said RF signal analysis in a plurality of radiation sessions.

20. The monitoring apparatus of claim 19, further comprising an attachment element configured for attaching the monitoring apparatus to a thorax of said patient.

21. The monitoring apparatus of claim 19, wherein said monitoring apparatus is substantially stationary, said plurality of radiation sessions being performed while said patient is in a monitoring position.

22. The monitoring apparatus of claim 19, wherein said at least one hardware processor is adapted to detect said dielectric related property based on a member of a group consisting of:

an accumulation of pulmonary fluid content, a dispersion of pulmonary fluid content, a concentration change in distribution of said pulmonary fluid, and a change composition of pulmonary fluid content.

23. The monitoring apparatus of claim 19, further comprising a dosage interface configured for providing treatment instructions according to said pulmonary fluid content level.

24. The monitoring apparatus of claim 19, further comprising an interface configured for communicating with a medical device adapted to examine breathing volumes of said patient, said at least one hardware processor being configured for performing said determining according to said breathing volumes.

25. The monitoring apparatus of claim 19, wherein said at least one hardware processor is configured to determine a pathological indicator according to said pulmonary fluid content level;

further comprising an output unit for generating a notification in response to said pathological indicator.

26. The monitoring apparatus of claim 19, further comprising an adjustment unit for receiving adjustment information related to said patient, said at least one hardware processor configured for performing said determining according to said adjustment information.

27. The monitoring apparatus of claim 19, wherein said probe having a plurality of antenna elements for transmitting and intercepting the RF radiation from a plurality of different areas.

28. The monitoring apparatus of claim 19, wherein said at least one hardware processor reduces an effect of a member of a group consisting of:

a posture change, a change in placement, and a change in a power of said RF radiation.

29. The monitoring apparatus of claim 19 wherein said at least one hardware processor is adapted for executing a code for generating a notification to a user according to said pulmonary fluid content level in light of at least one user defined threshold.

30. The monitoring apparatus of claim 19, wherein said at least one hardware processor is adapted for executing a code for performing at least one of:

monitoring the placement of the monitoring apparatus on the body of said patient in relation to an internal tissue, and

identifying at least one of misplacement, displacement, and disengagement of said monitoring apparatus in relation to an internal tissue.

31. The monitoring apparatus of claim 19, wherein said at least one hardware processor is adapted for executing a code for controlling a mechanical adjustment to change a position of the monitoring apparatus.

32. The monitoring apparatus of claim 19, wherein said plurality of radiation sessions are intermittent.

33. The monitoring apparatus of claim 19, wherein said at least one hardware processor is configured for detecting at least one of vital signs, trends of vital signs and physiological process of said patient, said at least one hardware processor being configured for calculating clinical state of said patient with respect to said dielectric related property in pulmonary fluid content and to at least one said vital signs, trends of vital signs and physiological process;

wherein said probe intercepts said at least one radio frequency (RF) radiation while the at least one thoracic tissue moves.

34. The monitoring apparatus of claim 19, wherein said determining comprises analyzing said difference in said signals among at least one of different segments of the signal and signals measured at different time instances.

35. The monitoring apparatus of claim 19, wherein during a period of said plurality of radiation sessions, said at least one hardware processor is adapted to at least one of the following:

reduce of at least one movement effect; and

generate guidance instructions for at least one of repositioning the monitoring apparatus and guiding the monitored patient to a posture.

36. The monitoring apparatus of claim 19, wherein during a period of said plurality of radiation sessions, said at least one hardware processor is adapted to, at least one of the following:

detect at least one of misplacement and disengagement of the monitoring apparatus;

identify a period for performing a data acquisition session;

identify said dielectric related property by at least one of calculating a baseline and identifying a normal range which are adjusted according to the patient; and

use a tracking algorithm for compensating for relative movements of an antenna of said probe in respect to points of interest.

37. The monitoring apparatus of claim 19, wherein said at least one hardware processor reduces the effect of a movement on said dielectric related property identification, said movement comprises a member of a group consisting of:

a thoracic movement, an internal physiological activity, and an external physiological activity irregularity.

38. The monitoring apparatus of claim 19, wherein said at least one hardware processor reduces the effect of a movement on said dielectric related property identification, said movement is a member of a group consisting of:

an organ movement, an antenna movement, a change of posture movement, a bodily movement, an activity related movement.

39. A method for determining a pulmonary fluid content level in at least one thoracic tissue using at least one hardware processor and at least one antenna element, comprising:

intercepting, using at least one antenna element, at least one radio frequency (RF) the range of 0.3 gigahertz (GHZ) to 20 GHZ from the at least one thoracic tissue of a patient in a plurality of radiation sessions;

using at least one hardware processor for;

identifying a differential signal from a difference between signals extracted from said RF radiation;

extracting at least one feature from the differential signal, said at least one feature is selected from a group consisting of;

a phase and an amplitude of said the differential signal;

detecting a dielectric related property of the at least one thoracic tissue according to said at least one feature;

determining a pulmonary fluid content level in said at least one thoracic tissue according to said dielectric related property; and

outputting a notification indicating said pulmonary fluid content level.