Detection of collisions in medical procedures

• US 20070228264A1
• Filed: 04/05/2006
• Published: 10/04/2007
• Est. Priority Date: 03/28/2006
• Status: Active Grant

• Current Assignee: IMRIS Inc.
• Original Assignee: IMRIS Inc.
• Inventors: Li, Jonathan
• Granted Patent: US 7,446,304 B2
• Time in Patent Office: Days
• US Class Current: 250/227.140
• CPC Class Codes: A61B 2090/0427 Prevention of contact
• CPC Class Codes: A61B 2090/065 for measuring contact or contact pressure
• CPC Class Codes: A61B 2090/374 NMR or MRI
• CPC Class Codes: A61B 6/102 Protection against mechanical damage, e.g. anti-collision devices
• CPC Class Codes: A61B 90/03 Automatic limiting or abutting means, e.g. for safety
• CPC Class Codes: A61B 90/06 Measuring instruments not otherwise provided for
• CPC Class Codes: G01D 5/35345 using Amplitude variations to detect the measured quantity
• CPC Class Codes: G01L 5/0052 measuring forces due to impact G01L5/0061, G01L5/14 take precedence; impact testing of structures G01M7/08; impact testing of material G01N3/00
• CPC Class Codes: G01M 11/086 Details about the embedment of the optical fiber within the DUT
• CPC Class Codes: G01R 33/28 Details of apparatus provided for in groups G01R33/44 - G01R33/64
• CPC Class Codes: G01R 33/288 Provisions within MR facilities for enhancing safety during MR, e.g. reduction of the specific absorption rate [SAR], detection of ferromagnetic objects in the scanner room
• CPC Class Codes: G02B 6/14 Mode converters

Abstract

A method of detecting collisions between elements in a medical procedure such as between a magnet and another element in the procedure mounting on the medical device a flexible body within which is mounted one or more parallel side by side optical fibers arranged such that the impact causes bending of one or more of the optical fibers and detecting changes in light transmission through the optical fiber to detect the bending and thus the collision. The single fiber or fibers are located in a junction between a lower body of resilient foam and a surface layer of a stiffer flexible material.

Claims

1. A method of detecting collisions between elements in a medical procedure comprising:

providing a medical device which is related to a second object in the procedure such that relative movement may occur in the medical procedure;

mounting on either the medical device or the second object a detection device responsive to impacts between the medical device and the second object;

the detection device comprising a flexible body within which is mounted at least one optical fiber arranged such that the impact causes bending of the optical fiber;

and detecting changes in light transmission through the at least one optical fiber to detect the bending and thus the collision.

2. The method according to claim 1 wherein the at least one fiber comprises a plurality of fibers arranged in an array.

3. The method according to claim 1 wherein the fibers in the array are generally side by side.

4. The method according to claim 1 wherein the fibers in the array are generally parallel.

5. The method according to claim 1 wherein the fibers in the array are buried beneath a surface of the flexible body.

6. The method according to claim 1 wherein the flexible body includes an under layer which is resilient and a surface layer which is stiffer than the under layer.

7. The method according to claim 6 wherein the at least one fiber is located at a junction between the layers.

8. The method according to claim 1 wherein the medical device comprises a magnet for use in magnetic resonance experiments.

9. The method according to claim 8 wherein the flexible body is mounted on the magnet.

10. The method according to claim 9 wherein the flexible body is generally annular and is located on an annular end of the magnet.

11. The method according to claim 10 wherein the magnet has a bore with longitudinal ribs in the bore of the magnet and wherein the flexible body includes projections matching the ribs in the bore.

12. The method according to claim 11 wherein the at least one fiber is bent so as to project into the projections.

13. The method according to claim 10 wherein the flexible body defines an end face at the end of the magnet and wherein the flexible body includes an end face layer and under body with the at least one fiber being located within the body.

14. The method according to claim 13 wherein the end face layer is stiffer than the under body layer and the at least one fiber is located at a junction between the layers.

15. An impact detection device comprising:

a flexible body arranged to be mounted on an object expected to be involved in an impact;

at least one optical fiber arranged such that the impact causes bending of the optical fiber;

and a sensing system for detecting changes in light transmission through the at least one optical fiber to detect the bending and thus the collision.

16. The device according to claim 15 wherein the at least one fiber comprises a plurality of fibers arranged in an array.

17. The device according to claim 15 wherein the fibers in the array are generally side by side.

18. The device according to claim 15 wherein the fibres in the array are generally parallel.

19. The device according to claim 15 wherein the fibers in the array are buried beneath a surface of the flexible body.

20. The device according to claim 15 wherein the flexible body includes an under layer which is resilient and a surface layer which is stiffer than the under layer.