System and method for visualizing tissue during ablation procedures

• US 8,900,219 B2
• Filed: 04/14/2009
• Issued: 12/02/2014
• Est. Priority Date: 07/14/1999
• Status: Expired due to Term

• Current Assignee: Cardiofocus Incorporated
• Original Assignee: Cardiofocus Incorporated
• Inventors: Sinofsky, Edward L., Melsky, Gerald, Sagon, Stephen W., Farr, Norman E.
• Primary Examiner(s): ROANE, AARON F
• Application Number:
  US12/423,137
• Publication Number:
  US 20090326320A1
• Time in Patent Office: 2,058 Days
• Field of Search: 606/2, 606 14- 16, 606/32, 606/41
• US Class Current: 606/2
• CPC Class Codes: A61B 1/00087 Tools A61B17/00234 takes precedence
• CPC Class Codes: A61B 1/00165 with light-conductive means, e.g. fibre optics A61B1/07 takes precedence
• CPC Class Codes: A61B 1/0638 providing two or more wavelengths
• CPC Class Codes: A61B 1/07 using light-conductive means, e.g. optical fibres
• CPC Class Codes: A61B 18/24 with a catheter A61B18/26, A61B18/28 take precedence
• CPC Class Codes: A61B 2017/00057 Light
• CPC Class Codes: A61B 2018/00011 with fluids
• CPC Class Codes: A61B 2018/00357 Endocardium
• CPC Class Codes: A61B 2018/00577 Ablation
• CPC Class Codes: A61B 2018/00642 with feedback, i.e. closed loop control
• CPC Class Codes: A61B 2018/0069 using fuzzy logic
• CPC Class Codes: A61B 2018/00904 Automatic detection of target tissue
• CPC Class Codes: A61B 2018/00982 combined with or comprising means for visual or photographic inspections inside the body, e.g. endoscopes
• CPC Class Codes: A61B 2576/023 for the heart
• CPC Class Codes: A61B 5/0036 including treatment, e.g., using an implantable medical device, ablating, ventilating
• CPC Class Codes: A61B 5/0044 for the heart
• CPC Class Codes: A61B 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 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 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/7264 Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems neural networks per se G06N3/00; expert systems per se G06N5/00
• CPC Class Codes: A61B 5/743 : Displaying an image simultaneously with additional graphical information, e.g. symbols, charts, function plots

Abstract

Systems for visualizing cardiac tissue during an ablation procedure are provided. In general, the systems include an imaging module configured to measure absorbance data at first and second wavelengths wherein the ratio of these absorbance values identifies the nature of the tissue (e.g., lesion, de novo tissue, etc.). The imaging module can also include a video system having at least two chips with corresponding bandpass filters centered at the first and second target wavelengths. The system can also include a processor and/or video monitor for combining the images produced by the various chips, determining treated and non-treated tissue based on the ratio of absorbance values at the target wavelengths, and displaying images of the treatment area. Methods of visualizing cardiac treatment areas during ablation procedures are also provided herein.

Claims

1. A tissue visualization system, comprising:

a reflectivity sensor sized and shaped to be slidably disposed within a lumen of a catheter, and configured to capture reflected light from an area of tissue;

an imaging module in communication with the reflectivity sensor, and configured to detect a first amount of light reflected by the area of tissue at a first, predetermined waveband and a second amount of light reflected by the area of tissue at a second, predetermined waveband;

a processor in communication with the imaging module, and configured in real time to compare the first amount of light relative to the second amount of light, and further configured in real time to classify the area of tissue as a lesion or as de novo tissue if the first amount of light is less than or greater than the second amount of light, respectively; and

a display that is in communication with the processor for displaying, in real time, an image of the area of tissue obtained from the imaging module, wherein the processor is configured to visually differentiate, on the display, tissue that is classified as a lesion from de novo tissue to allow a user to distinguish the lesion from de novo tissue on the display and evaluate a progress of a medical procedure;

wherein the first and second wavebands are specifically selected such that a comparison between a degree of light reflectance at each of the first and second wavebands is indicative of whether the tissue being analyzed is a lesion or de novo tissue.

2. The system of claim 1, wherein the first, predetermined waveband is centered at 550 nm, and the second, predetermined waveband is centered at 560 nm.

3. The system of claim 2, wherein each waveband is 40 nm wide.

4. The system of claim 1, wherein the imaging module includes a video camera having a plurality of video chips with at least a first and a second video chip configured to generate a first image and a second image based on the first predetermined wavelength band and the second predetermined wavelength band, respectively.

5. The system of claim 4, wherein the first predetermined wavelength band is centered at 550 nm, and the second wavelength band is centered at 560 nm.

6. The system of claim 5, wherein the first and the second video chips are in communication with a first and a second 40 nm wide bandpass filter, respectively.

7. The system of claim 4, wherein the video camera further includes a third video chip configured to generate a third image based on a third predetermined wavelength band which is selected from a red waveband or a blue waveband.

8. The system of claim 4, wherein the processor is configured to generate a combined image from the first image and the second image generated by the first and second video chips, respectively, the combined image being the image that is displayed on the display.

9. The system of claim 8, wherein the visual differentiation performed by the processor on the image comprises a false coloring indicative of a treatment status that is applied to at least a portion of the combined image.

10. The system of claim 9, wherein the processor is configured to apply a false coloring to any portion of the combined image which is classified as lesion.

11. The system of claim 9, wherein the display comprises a video monitor configured to display a real-time view of the combined image.

12. The system of claim 1, wherein the reflectivity sensor is a fiber-optic endoscope.

13. The system of claim 12, further including a fiber optic energy emitter configured to irradiate partial ring-like areas of tissue.