Imaging systems and methods for tissue differentiation, e.g., for intraoperative visualization

A method comprising:

• administering two or more different probe species, each comprising a spectrally differentiable fluorescent reporter, to a lymphatic system of a human subject with a tumor, wherein a first probe species is administered to a tumor site of the subject, and a second probe species is administered to an extremity of the subject;
• directing excitation light into lymph nodes of the subject, thereby exciting the fluorescent reporters having spectrally distinguishable emission wavelengths;
• identifying a lymph node that drains the tumor site, and identifying another lymph node that drains the extremity, using a multichannel fluorescence camera system that simultaneously detects the spectrally distinguishable emission wavelengths in real-time;
• and
• displaying in real-time the fluorescent reporters having spectrally distinguishable emission wavelengths to graphically differentiate between the lymph node that drains the extremity and the lymph node that drains the tumor site,
• wherein the two or more different probe species each comprise a silica nanoparticle, and
• wherein the silica nanoparticle has a diameter less than 10 nm.

A method comprising:

• administering two or more different probe species, each comprising a spectrally differentiable fluorescent reporter, to a lymphatic system of a human subject, wherein a first probe species is administered to a trunk of the subject, and a second probe species is administered to an extremity of the subject;
• directing excitation light into lymph nodes of the subject, thereby exciting the fluorescent reporters having spectrally distinguishable emission wavelengths;
• identifying a lymph node in the trunk for harvesting in transplantation for lymphedema, and identifying another lymph node that drains the extremity, using a multichannel fluorescence camera system that simultaneously detects the spectrally distinguishable emission wavelengths in real-time;
• and
• displaying in real-time the fluorescent reporters having spectrally distinguishable emission wavelengths to graphically differentiate between the lymph node that drains the extremity and the lymph node for harvesting,
• wherein the two or more different probe species each comprise a silica nanoparticle, and
• wherein the silica nanoparticle has a diameter less than 10 nm.