Method and apparatus for detecting tumorous tissue

• US 6,763,262 B2
• Filed: 05/18/2001
• Issued: 07/13/2004
• Est. Priority Date: 05/19/2000
• Status: Expired due to Fees

• Current Assignee: TuiLaser AG (Coherent Corp.)
• Original Assignee: TuiLaser AG (Coherent Corp.)
• Inventors: Hohla, Alexander, Leipert, Gunther
• Primary Examiner(s): Bennett, Henry
• Assistant Examiner(s): Dahbour, Fadi H.
• Application Number:
  US09/860,365
• Publication Number:
  US 20020128557A1
• Time in Patent Office: 1,152 Days
• Field of Search: 600/476, 600/477, 600/478, 600/473, 600/407-436, 356/317, 356/318, 356/446, 356/448
• US Class Current: 600/476
• CPC Class Codes: A61B 5/0071 by measuring fluorescence emission
• CPC Class Codes: A61B 5/0084 for introduction into the body, e.g. by catheters A61B5/1459 takes precedence
• CPC Class Codes: A61B 5/0086 using infrared radiation
• CPC Class Codes: G01N 21/645 Specially adapted constructive features of fluorimeters
• CPC Class Codes: G01N 21/6486 Measuring fluorescence of biological material, e.g. DNA, RNA, cells G01N21/6428 takes precedence

Abstract

The present invention relates to an apparatus for detecting tumorous tissue comprising at least one excitation light source 12, which first excitation light source 12 emits a first excitation light 34 of a wavelength of between 300 nm and 314 nm and includes at least one optical fiber 14 for guiding the first excitation light 34 to an object field 18 of the tissue 16 to be examined, and at least one lens 24 for projecting an auto-fluorescence signal and/or a remission signal 20 of the tissue 16, generated by the first excitation light 34, to a CCD or ICCD chip of a camera 22, as well as a data processing system 28 for processing the signals transmitted by the camera 22, said lens 24 being capable of processing UV light and being designed such that at least two images 48, 50 from different spectral regions of the fluorescent object field 18 are generated and projected to the CCD or ICCD chip, of which at least one image 48, 50 represents the UV range and another, different wavelength range of the auto-fluorescence signal and/or of the remission signal 20 of said object field 18. The invention is further directed to a method for detecting tumorous tissue.

Claims

1. An apparatus for detecting tumorous tissue, comprising:

at least one first excitation light source for emitting a first excitation light of a wavelength of between 300 nm and 314 nm;

at least one optical fiber for guiding said first excitation light to an object field of the tissue to be examined;

at least one lens for projecting an auto-fluorescence signal and/or remission signal of said tissue, generated by means of said first excitation light, to a CCD or ICCD chip of a camera;

at least one data processing system for processing signals transmitted by said camera wherein;

said lens includes a ridge prism and is capable of processing UV light,

said lens generates at least two images of which at least one image represents the UV range and another represents a different wavelength range of the auto-fluorescence signal and/or of the remission signal of the object field.

2. The apparatus as claimed in claim 1, wherein said lens includes at least one achromatic UV lens.

3. The apparatus as claimed in claims 1, wherein said apparatus includes a second excitation light source for emitting a second excitation light of a wavelength of between 312 nm and 340 nm and/or between 350 nm and 410 nm.

4. The apparatus as claimed in claim 1, wherein said first excitation light source is a XeF, XeCl or HeCd laser.

5. The apparatus as claimed in claims 3 or 4, wherein said second excitation light source is a Xe, Hg or deuterium lamp or a N₂ laser.

6. A method for detecting tumorous tissue comprising:

a) illuminating tissue with a first excitation light of a wavelength of between 300 nm and 314 nm from a first excitation light source and generating an auto-fluorescence and/or remission of an object field of said illuminated tissue;

b) generating at least two images from different spectral regions of said fluorescent object field by means of a lens of a camera and projecting them to a CCD or ICCD chip of said camera, of which at least one image represents the UV range and another representing a, different wavelength range of said auto-fluorescence signal and/or said remission signal of said object field;

c) transmitting the image/video signals generated in said camera to a data processing system;

d) subtracting background signals from said generated image/video signals;

e) inputting said UV image into a blue channel and computing it together therewith and inputting said other image into a green and/or red channel and computing it together therewith;

f) amplifying or diminishing the individual color channels for obtaining a standard color setting for normal, non-tumorous tissue; and

g) evaluating the color-coded images or their color-coded image/video signals for distinguishing normal, healthy tissue from tumorous tissue.

7. The method as claimed in claim 6, wherein two images are generated in procedural step b), of which one image represents the UV range and the other image represents the visible wavelength range of the auto-fluorescence signal and/or of the remission signal of the object field.

8. The method as claimed in claim 6, wherein procedural step a), said tissue is illuminated with light from a first excitation light source as well as from a second excitation light source for emitting a second excitation light of a wavelength of between 312 nm and 340 nm and/or between 350 nm and 410 nm.

9. The method as claimed in claim 8, wherein in procedural step b) two images are generated of which a first image represents the UV range and the other image the infrared range of the auto-fluorescence signal and/or of the remission signal of the object field.

10. The method as claimed in claim 8, wherein in procedural step b) three images are generated of which a first image represents the UV range, the second image represents the visible wavelength range and the third image represents the infrared range of the auto-fluorescence signal and/or of the remission signal of said object field.

11. The method as claimed in one of claims 6 to 10, wherein the color-coded images or color-coded image/video signals are evaluated in procedural step g) by comparing and displaying the generated standard color setting for normal, non-tumorous tissue with the generated color setting for tumorous tissue.

12. The method as claimed in one of claims 6 to 10, wherein the evaluation of the color-coded images or color-coded image/video signals in procedural step g) comprises:

g1) canceling the gamma correction by a correcting function and linearizing the color channels;

g2) forming the intensity ratios of the color channels and logarithmizing the result, at the same time characterizing the tissue in that positive values denote tumorous tissue and negative values denote normal, healthy tissue; and

g3) averaging the brightness values of the color channels and computing them together with a ratio image formed in procedural step g2) for illustrating the distribution geometry of the different kinds of tissue.