Apparatus for enhancing the visibility of a luminous object inside tissue and methods for same

An imaging system which enhances the visibility of an object located inside tissue, comprising:

• means for applying a single contrast agent to the tissue, thereby staining the object;
• means for selecting at least one illuminating wavelength;
• means for illuminating the tissue at said selected illuminating wavelength;
• means for selecting a plurality of imaging wavelengths;
• means for detecting a first fluorescence image signal emitted from said stained object having a first emission intensity at a first image wavelength and a second fluorescence image signal emitted from said stained object having a second emission intensity at a second image wavelength, wherein emissions from said contrast agent are substantially dissimilar at said first and second image wavelengths and emissions from said tissue are substantially similar at said first and second image wavelengths and wherein said substantially dissimilar emissions from said contest agent are determined by said first and second imaging wavelengths;
• and
• means for performing normalization and subtraction of said detected image signals, whereby a new image signal is generated in which an image of the stained object is enhanced.

A method for imaging an object located inside tissue comprising the steps:

• applying a single contrast agent to the object, whereby the object becomes a luminous object;
• illuminating the tissue and said object at a selected wavelength;
• recording fire signals having a first emission intensity at a first imaging wavelength;
• recording second signals having a second emission intensity at a second imaging wavelength, wherein emissions from said contrast agent are substantially dissimilar at said first and second imaging wavelengths and emissions from said tissue are substantially similar at said first and second imaging wavelengths and wherein said substantially dissimilar emissions from said contrast agent are determined by said first and second imaging wavelengths;
• and
• subtracting said first signals from said second signals, whereby an image component resulting from the tissue is minimized while an image component resulting from said luminous object is enhanced.