Implants using ultrasonic backscatter for sensing physiological conditions

Patent metadata

Field	Value
Publication number	US-12239408-B2
Application number	US-202318447228-A
Country	US
Kind code	B2
Filing date	Aug 9, 2023
Priority date	Jul 7, 2016
Publication date	Mar 4, 2025
Grant date	Mar 4, 2025

Abstract

Described herein is an implantable device having a sensor configured to detect an amount of an analyte, a pH, a temperature, strain, or a pressure; and an ultrasonic transducer with a length of about 5 mm or less in the longest dimension, configured to receive current modulated based on the analyte amount, the pH, the temperature, or the pressure detected by the sensor, and emit an ultrasonic backscatter based on the received current. The implantable device can be implanted in a subject, such as an animal or a plant. Also described herein are systems including one or more implantable devices and an interrogator comprising one or more ultrasonic transducers configured to transmit ultrasonic waves to the one or more implantable devices or receive ultrasonic backscatter from the one or more implantable devices. Also described are methods of detecting an amount of an analyte, a pH, a temperature, a strain, or a pressure.

First claim

What is claimed is:

1. A system, comprising:
(a) an implantable device, comprising:
a sensor configured to detect a cranial pressure; and
an ultrasonic transducer with a length of about 5 mm or less in the longest dimension, the ultrasonic transducer configured to receive ultrasonic waves that power the implantable device, receive a current modulated based on the pressure detected by the sensor, and emit a pressure-dependent ultrasonic backscatter based on the current received by the ultrasonic transducer; and

(b) an interrogator comprising one or more ultrasonic transducers configured to transmit the ultrasonic waves that power the implantable device, and receive the ultrasonic backscatter from the implantable device.

2. The system of claim 1 , wherein the sensor is an optical sensor.

3. The system of claim 1 , wherein the sensor comprises a microelectromechanical system (MEMS) sensor.

4. The system of claim 1 , wherein the ultrasonic transducer is a bulk piezoelectric transducer, a piezoelectric micro-machined ultrasonic transducer (PMUT) or a capacitive micro-machined ultrasonic transducer (CMUT).

5. The system of claim 1 , wherein the implantable device is about 5 mm or less in length in the longest dimension.

6. The system of claim 1 , wherein the volume of the implantable device has a volume of about 5 mm 3 or less.

7. The system of claim 1 , wherein the implantable device further comprises an integrated circuit.

8. The system of claim 7 , wherein the integrated circuit comprises one or more of a power circuit, a driver configured to provide current to the sensor, a front end configured to receive a signal from the sensor, or a digital circuit.

9. The system of claim 7 , wherein the integrated circuit comprises a digital circuit configured to operate a modulation circuit.

10. The system of claim 9 , wherein the digital circuit is configured to transmit a digital signal to the modulation circuit, wherein the digital signal is based on the detected cranial pressure.

11. The system of claim 1 , wherein the implanted device is at least partially encapsulated by a biocompatible material.

12. The system of claim 1 , wherein the interrogator is configured to be wearable by a subject.

13. A method of detecting a cranial pressure, comprising:
powering an implantable device implanted in a subject using ultrasonic waves emitted from an interrogator comprising one or more ultrasonic transducers, wherein the implantable device comprises an ultrasonic transducer with a length of 5 mm or less in the longest dimension and a sensor configured to measure the cranial pressure;
converting energy from the ultrasonic waves into an electrical current;
measuring the cranial pressure using the sensor;
producing a modulated electrical current based on the measured cranial pressure;
transducing the modulated electrical current into an ultrasonic backscatter that encodes the measured cranial pressure;
emitting the ultrasonic backscatter to the interrogator; and
receiving the ultrasonic backscatter.

14. The method of claim 13 , comprising transmitting the electrical current from the ultrasonic transducer of the implantable device to the sensor.

15. The method of claim 13 , comprising transmitting the electrical current from the ultrasonic transducer of the implantable device to an integrated circuit, and transmitting a second electrical current from the integrated circuit to the sensor.

16. A system, comprising:
(a) an implantable device configured to be implanted in an organ or on, within, or proximal to a blood vessel, comprising:
a sensor configured to detect a blood pressure or a pulse rate; and
an ultrasonic transducer with a length of about 5 mm or less in the longest dimension, the ultrasonic transducer configured to receive ultrasonic waves that power the implantable device, receive a current modulated based on the blood pressure or pulse rate detected by the sensor, and emit blood pressure-dependent or pulse-rate-dependent ultrasonic backscatter based on the current received by the ultrasonic transducer; and

(b) an interrogator comprising one or more ultrasonic transducers configured to transmit the ultrasonic waves that power the implantable device, and receive the ultrasonic backscatter from the implantable device.

17. The system of claim 16 , wherein the sensor is configured to detect the blood pressure.

18. The system of claim 16 , wherein the sensor is configured to detect the pulse rate.

19. The system of claim 16 , wherein the implantable device is configured to be implanted on the blood vessel.

20. The system of claim 16 , wherein the implantable device is configured to be implanted within the blood vessel.

21. The system of claim 16 , wherein the sensor is an optical sensor.

22. The system of claim 16 , wherein the sensor comprises a microelectromechanical system (MEMS) sensor.

23. The system of claim 16 , wherein the ultrasonic transducer is a bulk piezoelectric transducer, a piezoelectric micro-machined ultrasonic transducer (PMUT) or a capacitive micro-machined ultrasonic transducer (CMUT).

24. The system of claim 16 , wherein the implantable device is about 5 mm or less in length in the longest dimension.

25. The system of claim 16 , wherein the volume of the implantable device has a volume of about 5 mm 3 or less.

26. The system of claim 16 , wherein the implantable device further comprises an integrated circuit.

27. The system of claim 26 , wherein the integrated circuit comprises one or more of a power circuit, a driver configured to provide current to the sensor, a front end configured to receive a signal from the sensor, or a digital circuit.

28. The system of claim 27 , wherein the integrated circuit comprises a digital circuit configured to operate a modulation circuit.

29. The system of claim 16 , wherein the digital circuit is configured to transmit a digital signal to the modulation circuit, wherein the digital signal is based on the blood pressure or the pulse rate.

30. The system of claim 16 , wherein the implanted device is at least partially encapsulated by a biocompatible material.

31. The system of claim 16 , wherein the interrogator is configured to be wearable by a subject.

32. A method of detecting a blood pressure or pulse rate, comprising:
powering an implantable device using ultrasonic waves emitted from an interrogator comprising one or more ultrasonic transducers, wherein the implantable device comprises an ultrasonic transducer with a length of 5 mm or less in the longest dimension and a sensor configured to measure the blood pressure or pulse rate, and wherein the implantable device is implanted in an organ or on, within, or proximal to a blood vessel of a subject;
converting energy from the ultrasonic waves into an electrical current;
measuring the blood pressure or pulse rate using the sensor;
producing a modulated electrical current based on the measured blood pressure or pulse rate;
transducing the modulated electrical current into an ultrasonic backscatter that encodes the measured blood pressure or pulse rate;
emitting the ultrasonic backscatter to the interrogator; and
receiving the ultrasonic backscatter.

33. The method of claim 32 , comprising transmitting the electrical current from the ultras

Assignees

• Univ California

Inventors

• Maharbiz Michel M
• Carmena Jose M
• Anwar Mekhail
• Ozilgen Burak A
• Seo Dongjin
• Fava Federica

Classifications

• A61N1/372

  Arrangements in connection with the implantation of stimulators · CPC title

• G01N27/327

  Biochemical electrodes {, e.g. electrical or mechanical details for in vitro measurements} · CPC title

• B06B1/06

  operating with piezoelectric effect or with electrostriction (piezoelectric or electrostrictive devices per se H10N30/00) · CPC title

• A61N2007/0021

  Neural system treatment · CPC title

• A61B8/0808

  for diagnosis of the brain · CPC title