Device for measuring the mechanical properties of biological tissue

• US 5,840,041 A
• Filed: 03/14/1997
• Issued: 11/24/1998
• Est. Priority Date: 09/16/1994
• Status: Expired due to Fees

• Current Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Original Assignee: Fraunhofer Gesellschaft Zur Foerderung Der Angewandten Forsching E.V.
• Inventors: Meyer, Jorg-Uwe, Petter, Erwin
• Primary Examiner(s): Hindenburg, Max
• Assistant Examiner(s): MARMOR II, CHARLES ALAN
• Application Number:
  US08/816,996
• Time in Patent Office: 620 Days
• Field of Search: 600/382, 600/383, 600/402, 600/547, 600/552
• US Class Current: 600/547
• CPC Class Codes: A61B 3/16 for measuring intraocular pressure, e.g. tonometers
• CPC Class Codes: A61B 5/0051 by applying vibrations
• 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 5/442 Evaluating skin mechanical properties, e.g. elasticity, hardness, texture, wrinkle assessment
• CPC Class Codes: A61B 5/6843 Monitoring or controlling sensor contact pressure

Abstract

An apparatus for measuring the mechanical properties of biological tissue d the use of the apparatus is provided. The apparatus generates a magnetic field by means of a coil system comprising a permanent magnet as the actuator and a conductive foil as the sensor.

Claims

1. An apparatus for measuring the mechanical properties of biological tissue comprising:

a device for generating a magnetic field by means of a coil system;

a device for mechanically exciting the tissue by means of a permanent magnet as the actuator and a conductive foil as a sensor; and

a device for measuring any change in impedance, wherein said sensor is inductively coupled to said coil system.

2. An apparatus according to claim 1, wherein the mass of said actuator and said sensor is less than approximately 0.2 g.

3. An apparatus according to claim 1, wherein the apparatus is operably connected to an endoscope and said conductive foil being designed as the distal end of the endoscope.

4. An apparatus according to claim 3, further comprising an elastic foil disposed between the tissue to be examined and said conductive foil.

5. An apparatus according to claim 1, the foil, the magnet, or both being operably embedded in a contact lens.

6. A method for measuring the mechanical properties of biological tissue comprising operably contacting the apparatus of claim 1 to said tissue and measuring the responses.

7. A method as claimed in claim 6, wherein the mechanical property to be measured is intraocular pressure.

8. A method as claimed in claim 6, wherein the biological tissue is skin.

9. A method as claimed in claim 6, wherein the apparatus of claim 1 is operably connected to an endoscope.

10. A method as claimed in claim 6, wherein the apparatus of claim 1 is operably connected to an endoscope.

12. An apparatus according to claim 2, further comprising a conductive foil placed on said soft magnetic foil.

17. A method for measuring the mechanical properties of biological tissue comprising operably contacting the apparatus of claim 2 to said tissue and measuring the responses.

18. A method as claimed in claim 17, wherein the mechanical property to be measured is intraocular pressure.

19. A method as claimed in claim 17, wherein the biological tissue is skin.

11. An apparatus for measuring the mechanical properties of biological tissue comprising:

a device for generating a magnetic field by means of a coil system;

a device for mechanically exciting the tissue by means of a foil comprising a soft magnetic material; and

a device for measuring any change in impedance,

wherein said foil comprising a soft magnetic material is capable of acting as an actuator and is simultaneously designed as a sensor for measuring the mechanical vibrations of the tissue, and wherein said sensor is inductively coupled to said coil system.

13. An apparatus according to claim 11, wherein the mass of said actuator and said sensor is less than approximately 0.2 g.

14. An apparatus according to claim 11, wherein the apparatus is operably connected to an endoscope and said soft magnetic material foil being designed as the distal end of the endoscope.

15. An apparatus according to claim 14, further comprising an elastic foil disposed between the tissue to be examined and said soft magnetic material foil.

16. An apparatus according to claim 11, the foil comprising the soft magnetic material being operably embedded in a contact lens.

20. An apparatus for measuring the mechanical properties of biological tissue, comprising:

a soft magnetic material capable of simultaneously acting as an actuator to mechanically excite the tissue and as a sensor of the vibrations in the tissue;

a magnetic field generator; and

an impedance recorder;

wherein the apparatus may be placed on a biological tissue.

21. An apparatus for measuring mechanical properties of biological tissue, comprising:

an excitation system;

a mechanical actuator and sensor adaptable to contact the biological tissue, said mechanical actuator and sensor wirelessly coupling with said excitation system; and

an impedance measuring system which measures any change in impedance of said sensor.