Automatic calibration systems and methods of use

• US 8,395,781 B2
• Filed: 02/23/2012
• Issued: 03/12/2013
• Est. Priority Date: 07/12/2007
• Status: Active Grant

• Current Assignee: Volcano Corporation (Koninklijke Philips N.V.)
• Original Assignee: Volcano Corporation (Koninklijke Philips N.V.)
• Inventors: Kemp, Nathaniel J., Elmaanaoui, Badr, Begin, Elizabeth
• Primary Examiner(s): Toatley, Gregory J
• Assistant Examiner(s): BOLOGNA, DOMINIC JOSEPH
• Application Number:
  US13/403,471
• Publication Number:
  US 20120162660A1
• Time in Patent Office: 383 Days
• Field of Search: 356/243.8, 356/394, 356477-483, 356/73.1, 600/310, 600/341, 600476-480
• US Class Current: 356/479
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• CPC Class Codes: A61B 5/0073 by tomography, i.e. reconstruction of 3D images from 2D projections A61B5/0066 takes precedence
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/6852 Catheters
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: G01B 2290/25 Fabry-Perot in interferometer, e.g. etalon, cavity
• CPC Class Codes: G01B 9/02004 using frequency scans
• CPC Class Codes: G01B 9/02057 by using common path configuration, i.e. reference and object path almost entirely overlapping
• CPC Class Codes: G01B 9/02069 Synchronization of light source or manipulator and detector
• CPC Class Codes: G01B 9/02083 characterised by particular signal processing and presentation
• CPC Class Codes: G01B 9/02091 Tomographic interferometers, e.g. based on optical coherence
• CPC Class Codes: G01M 11/31 with a light emitter and a light receiver being disposed at the same side of a fibre or waveguide end-face, e.g. reflectometers
• CPC Class Codes: G01N 21/274 Calibration, base line adjustment, drift correction
• CPC Class Codes: G01N 21/4795 spatially resolved investigating of object in scattering medium in vivo A61B

Abstract

The disclosed automatic calibration systems and methods provide a repeatable way to detect internal catheter reflections and to shift the internal catheter reflections to calibrate an image.

Claims

1. A method of calibrating a catheter, comprising:

providing a template of catheter reflection lines specific to an optical coherence tomography catheter;

obtaining an image in the catheter;

comparing the template to catheter reflection lines of the image; and

adjusting the Z-offset of the catheter based on the comparison step to align the image catheter reflection lines with the template.

2. The method of claim 1, wherein the template is stored or operably accessible with the catheter.

3. The method of claim 1, wherein the template is derived directly from another image obtained in the catheter.

4. The method of claim 1, wherein the comparing step comprises matching the template with a signal of the image and identifying a peak.

5. The method of claim 4, wherein the image is binary.

6. The method of claim 4, further comprising selecting the peak that corresponds to a strongest template match, the strongest template match representing one of the catheter reflection lines of the image.

7. The method of claim 6, wherein the peak is above a certain value.

8. The method of claim 4, further comprising changing the Z-offset position if the image does not match the template;

obtaining a second image in the catheter at the changed Z-offset position; and

performing the steps of comparing and adjusting on the second image.

9. The method of claim 1, wherein the adjusting Z-Offset step comprises mechanically shifting a Variable Delay Line.

10. The method of claim 4, wherein the Z-offset is adjusted to align the image catheter reflection lines with the template if an intensity of the peak of the image matches the template.

11. The method of claim 6, wherein the Z-offset is adjusted to align the image catheter reflection lines with the template based on the strongest template match.