MEDICAL APPARATUS WITH A SENSOR FOR DETECTING A FORCE

• US 20100094163A1
• Filed: 03/04/2008
• Published: 04/15/2010
• Est. Priority Date: 03/07/2007
• Status: Abandoned Application

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Deladi, Szabolcs, Mihajlovic, Nenad, Kahlert, Joachim
• Application Number:
  US12/529,372
• Publication Number:
  US 20100094163A1
• Time in Patent Office: Days
• US Class Current: 600/561
• CPC Class Codes: A61B 18/1492 having a flexible, catheter-like structure, e.g. for heart ablation A61B18/1477 takes precedence
• CPC Class Codes: A61B 18/22 the beam being directed along or through a flexible conduit, e.g. an optical fibre; Couplings or hand-pieces therefor
• CPC Class Codes: A61B 2090/064 for measuring force, pressure or mechanical tension
• CPC Class Codes: A61B 2090/065 for measuring contact or contact pressure
• CPC Class Codes: A61B 5/02154 by optical transmission
• CPC Class Codes: A61B 5/6843 Monitoring or controlling sensor contact pressure
• CPC Class Codes: A61B 5/6885 Monitoring or controlling sensor contact pressure
• CPC Class Codes: A61B 90/06 Measuring instruments not otherwise provided for
• CPC Class Codes: A61N 7/022 intracavitary
• CPC Class Codes: G01L 1/25 using wave or particle radiation, e.g. X-rays , microwaves, neutrons G01L1/24 takes precedence
• CPC Class Codes: G01L 9/0077 for measuring reflected light
• CPC Class Codes: Y10T 29/49002 Electrical device making

Abstract

The invention relates to a medical apparatus (120,130) having a sensor (100,110) for detecting a force acting on the medical apparatus (120,130) in a longitudinal direction. The medical apparatus (120,130) comprises an opto-mechanical force transducer having a flexible part (22,42) for receiving the force, an optical guide (1) having an outcoupling surface (11) that faces the flexible part (22,42) of the opto-mechanical force transducer, and a photodetector which detects an interference pattern composed of light (32) in the optical guide (1) that is reflected from the outcoupling surface (11) of the optical guide (1) and of light (33) in the optical guide (1) that is reflected from the flexible part (11) of the opto-mechanical force transducer. The use of the interference pattern composed of the light reflected from the out-coupling surface of the optical guide and the light reflected from the flexible part of the opto-mechanical force transducer results in a more accurate measurement of the force acting on the medical apparatus.

Claims

1. Medical apparatus (120,130) having a sensor (100,110) for detecting a force acting on the medical apparatus (120,130) in a longitudinal direction, the medical apparatus (120,130) comprising:

an opto-mechanical force transducer having a flexible part (22,42) for receiving the force;

an optical guide (1) having an outcoupling surface (11) that faces the flexible part (22,42) of the opto-mechanical force transducer; and

a photodetector which detects an interference pattern composed of light (32) in the optical guide (1) that is reflected from the outcoupling surface (11) of the optical guide (1) and of light (33) in the optical guide (1) that is reflected from the flexible part (11) of the opto-mechanical force transducer.

2. Medical apparatus (120,130) as claimed in claim 1, in which the flexible part (22,42) of the opto-mechanical force transducer comprises a protrusion (3) that receives the force.

3. Medical apparatus (120,130) as claimed in claim 2, in which the force comprises a contact force (F) between the protrusion (3) and a tissue surface inside a bodily lumen.

4. Medical apparatus (120,130) as claimed in claim 2, in which the protrusion (3) is located outside a path of light that is emitted from the outcoupling surface (11) of the optical guide (1).

5. Medical apparatus (120,130) as claimed in claim 1, in which the medical apparatus (120,130) comprises a closed space region (45) at least confined by the flexible part (42) and the outcoupling surface (11) of the optical guide (1) for detecting a pressure difference between the pressure of the environment and the pressure inside the closed space region (45).

6. Medical apparatus (120,130) as claimed in claim 1, in which the flexible part (22,42) of the opto-mechanical force transducer comprises a bottom surface (23) facing the outcoupling surface (11) of the optical guide (1) and a top surface (24,44) which receives the force and which is opposite to the bottom surface (23), and in which the flexible part (22,42) is supported at its outer side by a rigid supporting part (21,41) mounted on a part of the optical guide (9).

7. Medical apparatus (120,130) as claimed in claim 2, in which the flexible part (22,42) of the opto-mechanical force transducer comprises a flexible bridge connection (22) supported on each side by a rigid bridge support (21) mounted on a part of the optical guide (9) in which the protrusion (3) for receiving the force is located on the top surface (24) of the flexible bridge connection (22).

8. Medical apparatus (120,130) as claimed in claim 6, in which the flexible part (22,42) of the opto-mechanical force transducer comprises a fiber material at least partly coated with a reflective material on the bottom surface (23) or on the top surface (24,44) of the flexible part (22,42).

9. Medical apparatus (120,130) as claimed in claim 1, in which at least three opto-mechanical force transducers (100,110) are mounted around a central elongate part.

10. Medical apparatus (120,130) as claimed in claim 1, further comprising processing logic for computing the force from the interference pattern.

11. Medical apparatus (120,130) as claimed in claim 1, further comprising an optical fiber (50) for laser ablation and a laser source.

12. Method for manufacturing a sensor (100,110) for detecting a force acting on a medical apparatus (120,130) as claimed in claim 7, the method comprising the steps of:

mounting a first side of an optical guide (61) on a first foil;

removing a first part of the optical guide (61);

mounting a second side, which is opposing the first side, of the optical guide (61) on a second foil;

removing the first foil;

removing a second part of the optical guide (61), thereby forming a rectangular protrusion (62) at an end of the optical guide (61);

removing a part of the rectangular protrusion (62) thereby forming a flexible bridge connection (22) having a bottom surface facing an end surface of the optical guide (61) and a top surface opposite to the bottom surface, which flexible bridge connection (22) is supported at its outer side by a rigid bridge support (21), which is attached to the optical guide (61).