Visualization of heart wall tissue

• US 9,907,471 B2
• Filed: 10/08/2014
• Issued: 03/06/2018
• Est. Priority Date: 10/08/2013
• Status: Expired due to Fees

• Current Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Original Assignee: Board of Trustees of the Leland Stanford Junior University (Stanford Management Co.)
• Inventors: Caves, Jeffrey, Wang, Paul J., Farrell, Joyce E., Wandell, Brian A., Blasinski, Henryk
• Primary Examiner(s): ROZANSKI, MICHAEL T
• Application Number:
  US14/509,923
• Publication Number:
  US 20150099979A1
• Time in Patent Office: 1,245 Days
• CPC Class Codes: A61B 5/0044 for the heart
• CPC Class Codes: A61B 5/0071 by measuring fluorescence emission
• 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 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• CPC Class Codes: A61B 5/4848 Monitoring or testing the effects of treatment, e.g. of medication
• CPC Class Codes: A61B 5/7425 Displaying combinations of multiple images regardless of image source, e.g. displaying a reference anatomical image with a live image geometric transforms for image registration G06T3/14; enhancement using image fusion G06T5/50; algorithms for registration of images G06T7/30
• CPC Class Codes: A61B 5/748 Selection of a region of interest, e.g. using a graphics tablet

Abstract

Various aspects of the instant disclosure are directed to imaging tissue. As may be implemented in accordance with one or more embodiments, aspects of the present disclosure are directed to apparatuses and methods involving the following. A light source includes an array of light emitters that illuminate a tissue region of a heart wall with light at different wavelength ranges. A light collector collects multispectral images including respective images collected at each of the different wavelength ranges at which the tissue region is illuminated. A catheter positions the light source and light collector proximate the tissue region of the heart wall for respectively illuminating the tissue region and collecting the multispectral images. A display circuit collects and displays one or more images depicting a condition of the health of heart wall tissue, based on the respective images collected at the different ones of the wavelength ranges.

Claims

1. An apparatus comprising:

a light source including an array of light emitters configured and arranged to illuminate a tissue region of a heart wall with light at a plurality of different wavelength ranges;

a light collector configured and arranged to operate in conjunction with the light source to collect a plurality of multispectral images, including respective images of the tissue region of the heart collected at each of the different wavelength ranges at which the tissue region is illuminated by the light source, the plurality of multispectral images further including both reflected light from the tissue region in the plurality of different wavelength ranges and fluorescent light emitted by the tissue region;

a catheter configured and arranged with the light source and the light collector to position the light source and light collector proximate the tissue region of the heart wall for respectively illuminating the tissue region and collecting the multispectral images and to apply ablation energy to at least a portion of the tissue region of the heart wall; and

a display circuit configured and arranged to collect and display at least one image depicting a condition of the health of the heart wall tissue region, the at least one image including a visual distinction of scarred tissue from unscarred tissue or ablated tissue from tissue that is not ablated from the applied ablation energy, based on intensities of the reflected light and the fluorescent light as depicted in the respective images of the tissue region collected at each of the different ones of the wavelength ranges, wherein the catheter, the light source and the light collector are configured and arranged to operate with the light source and light collector positioned proximate the tissue region of the heart wall by illuminating the tissue region and collecting the multispectral images and with ablation energy applied to at least a portion of the tissue region of the heart wall, while the display circuit collects and displays said at least one image.

2. The apparatus of claim 1, wherein the display circuit is configured and arranged with the catheter, light source and light collector to collect and display the at least one image depicting a condition of the health of the heart wall tissue region by combining intensities of the reflected light and fluorescent light emitted by the tissue region responsive to the illumination at each of the different wavelength ranges and displaying an image that visually distinguishes scarred tissue from unscarred tissue, or that visually distinguishes ablated tissue from tissue that is not ablated, via the combined intensities.

3. The apparatus of claim 1, wherein the plurality of different wavelengths include four or more different bands of light, wherein the light source is configured and arranged to illuminate the tissue region with pulses of light, each pulse being of one of the plurality of different wavelengths, and wherein the light collector is configured and arranged with the light source to collect each of the multispectral images by, for each of the pulses of light, collecting an image of the tissue region as illuminated with the pulse of light.

4. The apparatus of claim 1, wherein

the light source is configured and arranged to illuminate the tissue region with pulses of light via sequential transmissions of the plurality of different wavelengths, each pulse being a different one of the plurality of different wavelengths,

the light collector is configured and arranged with the light source to collect each of the multispectral images at each of the plurality of different wavelength ranges by, for each of the pulses of light, collecting an image of the tissue region as illuminated with the pulse of light of the respective one of the plurality of different wavelengths, and

the display circuit is configured and arranged to display the at least one image depicting a condition of the health of the heart wall tissue region by combining portions of the respective images obtained for each pulse of light.

5. The apparatus of claim 1, wherein the display circuit is configured and arranged with the catheter, light source and light collector to collect and display the at least one image depicting a condition of the health of the heart wall tissue region by identifying a region of interest in one of the respective images, and displaying an image that visually distinguishes scar tissue from unscarred tissue by combining intensities of the region of interest from a plurality of the respective images, wherein scar tissue reflects light with a higher intensity than unscarred tissue.

6. The apparatus of claim 5, wherein combining intensities of the region of interest from a plurality of the respective images includes adding intensities of the region of interest as depicted in the plurality of respective images, and subtracting intensities of regions of the plurality of respective images that do not include the region of interest, the combined intensities of the region of interest being indicative of a type of tissue from which the light reflects.

7. The apparatus of claim 1, wherein the light source and light collector are configured and arranged to illuminate and collect light from the tissue region using wavelengths of light that reflect from scar tissue with a higher intensity relative to unscarred tissue.

8. The apparatus of claim 1,

further including an ablation electrode, configured to deliver energy at specified energy levels, and configured and arranged to ablate portions of the heart wall while the light source is active, and

wherein the light collector and catheter are configured and arranged with the light source to facilitate collection of light for, in response to the light emitted from the light source, the respective images from the heart wall, thereby providing an indication of the portions of the heart wall having been subjected to ablation.

9. The apparatus of claim 1, wherein

the light source is configured and arranged to effect a fluorescent light response from the tissue region by illuminating the tissue region with light that stimulates the tissue region to generate the fluorescent light,

the light collector is configured and arranged to collect both the reflected light from the tissue region and the fluorescent light emitted by the tissue region, and

the catheter and display circuit are respectively configured and arranged to collect the fluorescent light and display the at least one image based on both the reflected light and the fluorescent light.

10. The apparatus of claim 1, wherein the display circuit is configured and arranged to detect the intensity of reflected light that forms the multispectral images and to provide an indication of scarred tissue based on an expected intensity of light to be reflected from unscarred heart tissue at the respective wavelength ranges and the detected intensity of the reflected light.

11. The apparatus of claim 1, wherein:

the different wavelength ranges include wavelengths in at least one of ultraviolet, visible, and infrared spectra; and

the display circuit is configured and arranged with the light collector to generate a differential image representing a difference of the reflected light in respective images collected under the different wavelength ranges by mathematically combining the respective images.

12. The apparatus of claim 1, wherein the display circuit is configured and arranged to depict the condition of the health of the heart wall tissue region by depicting an indication of increased reflectance corresponding to ablated tissue.

13. The apparatus of claim 1, wherein the display circuit is configured and arranged with the light collector to display an image depicting a condition of ablation based on a difference in reflectance of respective wavelength ranges, by indicating tissue having been ablated as portions of the displayed image exhibiting greater differences in reflectance.

14. A method comprising:

illuminating a tissue region of a heart wall, by using a light source, with light at a plurality of different wavelength ranges;

collecting a plurality of multispectral images, by using a light collector, including respective images collected at each of the plurality of different wavelength ranges at which the tissue region is illuminated; and

collecting and displaying, using a circuit, at least one image depicting a condition of the health of the heart wall tissue region, based on the respective images collected at the different ones of the plurality of wavelength ranges, wherein illuminating the tissue region and collecting the plurality of multispectral images include positioning the light source and the light collector with a catheter proximate the tissue region of the heart wall for respectively illuminating the tissue region and collecting the multispectral images, and wherein the light source and the light collector are positioned proximate the tissue region of the heart wall and therein illuminate the tissue region and collect the multispectral images and ablation energy is applied to at least a portion of the tissue region of the heart wall, while the circuit is positioned with the light source and the light collector to collect and display said at least one image.

15. The method of claim 14, wherein collecting and displaying the at least one image depicting a condition of the health of the heart wall tissue region includes combining intensities of ones of the respective images and displaying an image that visually distinguishes scarred tissue from unscarred tissue, or that visually distinguishes ablated tissue from tissue that is not ablated, via the combined intensities, by generating a differential image representing a difference of the reflectance in the respective images collected under different wavelength ranges.

16. The method of claim 14, wherein

illuminating the tissue region of the heart wall, by using the light source, includes illuminating the tissue region with pulses of light, each pulse being of one of the plurality of different wavelength ranges, and

collecting the plurality of multispectral images, by using the light collector, includes collecting, for each of the pulses of light, an image of the tissue region as illuminated with the pulse of light.

17. The method of claim 16, wherein collecting and displaying the at least one image includes combining portions of the respective images obtained for each pulse of light and displaying the combined portions.

18. The method of claim 14, wherein

illuminating the tissue region of the heart wall, by using the light source, with light at a plurality of different wavelength ranges includes illuminating the tissue region of the heart wall, by using the light source, with light having a wavelength that reflects from scar tissue with a higher intensity relative to unscarred tissue, relative to other wavelengths of light, and

collecting and displaying the at least one image includes collecting light from the tissue region and using the higher intensity of the light reflecting from scar tissue to identify the scar tissue in the at least one image.

19. The method of claim 14, wherein collecting and displaying the at least one image includes identifying a region of interest in one of the respective images, adding intensities of the region of interest as depicted in the plurality of respective images, and

subtracting intensities of regions of the plurality of respective images that do not include the region of interest.

20. The method of claim 14, wherein

illuminating the tissue region of the heart wall, by using the light source, includes inducing a fluorescent light response from the tissue region by illuminating the tissue region with light that stimulates the tissue region to generate the fluorescent light response,

collecting the plurality of multispectral images, by using the light collector, includes collecting both reflected light from the tissue region and fluorescent light emitted by the tissue region, and

collecting and displaying include collecting the fluorescent light and displaying the at least one image based on both the reflected light and the fluorescent light.

21. An apparatus comprising:

a light source including an array of light emitters configured and arranged to induce a fluorescent response from a tissue region of a heart wall by illuminating the tissue region with light at a plurality of different wavelength ranges;

a filter configured and arranged to block reflected light;

a light collector configured and arranged to collect images of the fluorescent response of the tissue region as the tissue region is sequentially illuminated with light at the respective wavelength ranges, the wavelength of the fluorescent response being longer than the wavelengths of the illumination light;

a catheter configured and arranged with the light source and the light collector to position the light source and light collector proximate the tissue region of the heart wall for respectively illuminating the tissue region and collecting the fluorescent response; and

a display circuit configured and arranged to collect and display at least one image depicting a condition of the health of the heart wall tissue region, based on the collected images;

wherein the catheter, the filter, the light source and the light collector are configured and arranged to operate with the light source and light collector positioned proximate the tissue region of the heart wall by illuminating the tissue region and collecting multispectral images and with ablation energy applied to at least a portion of the tissue region of the heart wall, while the display circuit collects and displays said at least one image.