Method and apparatus for distinguishing cancerous tissue from benign tumor tissue, benign tissue or normal tissue using native fluorescence

• US 5,131,398 A
• Filed: 01/22/1990
• Issued: 07/21/1992
• Est. Priority Date: 01/22/1990
• Status: Expired due to Term

• Current Assignee: Mediscience Technology Corp. (Sensivida Medical Technologies, Inc.)
• Original Assignee: Mediscience Technology Corp. (Sensivida Medical Technologies, Inc.)
• Inventors: Tang, Guichen, Das, Bidyut, Alfano, Robert R.
• Primary Examiner(s): Smith, Ruth S.
• Application Number:
  US07/468,633
• Time in Patent Office: 911 Days
• Field of Search: 128/633, 128/634, 128/665, 128/395, 128/398, 356/435, 606/3, 606/15, 606/16
• 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 5/0091 for mammography
• CPC Class Codes: A61B 5/4312 Breast evaluation or disorder diagnosis A61B5/0091 takes precedence

Abstract

A method and apparatus for distingishing cancerous tumors and tissue from benign tumors and tissue or normal tissue using native fluorescence. The tissue to be examined is excited with a beam of monochromatic light at 300 nanometers (nm). The intensity of the native fluorescence emitted from tissue is measured at 340 and 440 nm. The ratio of the two intensities is then calculated and used as a basis for determining if the tissue is cancerous as opposed to benign or normal. The invention is based on the discovery that when tissue is excited with monochromatic light at 300 nm, the native fluorescence spectrum over the region from about 320 nm to 600 nm is the tissue that is cancerous and substantially different from the native fluorescence spectrum that would result if the tissue is either benign or normal. The technique is useful in invivo and in vitro testing of human as well as animal tissue.

Claims

1. Apparatus for determining if tissue is cancerous as opposed to benign or normal comprising:

a. a source of monochromatic light for illuminating a tissue at a wavelength which will fluoresce at wavelengths where the intensity for cancerous tissue and that of benign or normal tissue are different;

b. a pair of photodetector assemblies for measuring the intensity of light emitted from said tissue at two different wavelengths, each photodetector assembly including a photodetector and a filter, one filter being constructed to pass light at about 340 nm and the other at about 440 nm, each filter having a bandwidth of about 30 nm.;

c. a length of optical fiber bundle for transmitting said fluorescent light from said tissue to said pair of photodetector assemblies;

d. means coupled to said pair of photodetector assemblies for producing a processed signal corresponding to the signals from the pair of photodetector assemblies, and

e. means for displaying said processed signal.

2. A method for determining if tissue is cancerous as opposed to benign or normal comprising:

a. exciting a tissue to be examined with a beam of light that is at least substantially monochromatic, and at a wavelength between about 260 and 315 nm, whereby native fluorescence is emitted from the tissue,

b. measuring the intensity of the native flurorescence at two wavelengths, one wavelength being about 340 nm and the other wavelength being about 440 nm, and

c. determining if the tissue is cancerous as opposed to benign or normal in accordance with said measurements at said two wavelengths.