Acoustic biosensor for monitoring physiological conditions in a body implantation site

• US 6,475,170 B1
• Filed: 03/10/2000
• Issued: 11/05/2002
• Est. Priority Date: 12/30/1997
• Status: Expired due to Term

• Current Assignee: Remon Medical Technologies Ltd. (Boston Scientific Corporation)
• Original Assignee: Remon Medical Technologies Ltd. (Boston Scientific Corporation)
• Inventors: Penner, Avi, Doron, Eyal
• Primary Examiner(s): Shaver, Kevin
• Assistant Examiner(s): WINGOOD, PAMELA LYNN
• Application Number:
  US09/523,413
• Time in Patent Office: 970 Days
• Field of Search: 600/587, 600/593, 600/486, 600/488, 600/29, 600/30
• US Class Current: 600/587
• CPC Class Codes: A61B 2562/028 Microscale sensors, e.g. electromechanical sensors [MEMS]
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/02014 Determining aneurysm
• CPC Class Codes: A61B 5/02158 provided with two or more sensor elements
• CPC Class Codes: A61B 5/026 Measuring blood flow A61B3/1233, A61B3/1241 take precedence
• CPC Class Codes: A61B 5/031 Intracranial pressure
• CPC Class Codes: A61B 5/413 Monitoring transplanted tissue or organ, e.g. for possible rejection reactions after a transplant
• CPC Class Codes: A61M 2205/3523 using telemetric means
• CPC Class Codes: G01F 1/36 the pressure or differential pressure being created by the use of flow constriction
• CPC Class Codes: G01F 1/72 Devices for measuring pulsing fluid flows
• CPC Class Codes: H04R 17/00 Piezoelectric transducers; Electrostrictive transducers piezoelectric or electrostrictive elements in general H10N30/00; details of piezoelectric or electrostrictive motors, generators or positioners H10N30/00

Abstract

An acoustic biosensor is provided for deployment at an implantation site within a body, such as an abdominal aortic aneurysm. The biosensor includes a sensor element for measuring a physiological condition at the implantation site, and for generating an information signal representative of the physiological condition. The biosensor further includes a piezoelectric transducer element for converting an externally originated acoustic interrogation signal into energy for operating the sensor, and for modulating the interrogation signal, e.g., by employing a switching element to alternate the mechanical impedance of the transducer element, to transmit the information signal outside of the body.

Claims

1. A method for monitoring a physiological condition at an aneurysmal sac using an acoustic biosensor, the biosensor comprising:

a sensing element for measuring a physiological condition at the aneurysmal sac and for generating an information signal representative of the physiological condition; and

a transducer element for converting an acoustic interrogation signal into energy for operating the sensor and for modulating the interrogation signal to transmit the information signal, the method comprising;

implanting the biosensor into the aneurysmal sac;

providing an acoustic interrogation wave for impinging on the transducer element of the biosensor and thereby providing power to the sensing element, the acoustic wave having a reflected portion; and

modulating the reflected portion of the interrogation wave based on the information signal.

2. The method of claim 1, wherein the modulation of the reflected portion of the interrogation wave is accomplished by controlling mechanical impedance of the transducer element.

3. The method of claim 1, wherein the aneurysmal sac protrudes from an abdominal aorta.

4. A method for monitoring a physiological condition at an aneurysmal sac using an acoustic biosensor, the biosensor comprising:

a sensing element for measuring a physiological condition at the aneurysmal sac and for generating an information signal representative of the physiological condition; and

a transducer element for modulating the interrogation signal to transmit the information signal, the method comprising;

implanting the biosensor into the aneurysmal sac;

providing an acoustic interrogation wave for impinging on the transducer element of the biosensor, the acoustic wave having a reflected portion; and

modulating the reflected portion of the interrogation wave based on the information signal.

5. The method of claim 4, wherein the modulation of the reflected portion of the interrogation wave is accomplished by controlling mechanical impedance of the transducer element.

6. The method of claim 4, wherein the aneurysmal sac protrudes from an abdominal aorta.