Diagnoses of cancers and neurodegenerative diseases, such as Alzheimer's disease, are two applications suggested by the researchers in their report in Proceedings of the National Academy of Sciences (PNAS , June 10, 2003), "Live tissue intrinsic emission microscopy using multiphoton-excited native fluorescence and second harmonic generation." The researchers predict that it should be possible to obtain endoscopic and laparoscopic images of tissues at the cellular level from deep within living animals, or even human patients, thus enabling a new form of optical biopsy.
The researchers have demonstrated the new imaging technique by making live-tissue intrinsic fluorescence scans of autopsy samples from the brains of patients with Alzheimer's disease and by imaging mammary gland tumors in mice that serve as models of human cancer. Side-by-side comparison with conventional medical biopsy images of thin embalmed sections of the same organs reveals that the new method provides at least equal information, and in some cases contains additional diagnostic details not found in the conventional biopsies, which require invasive surgery.
Another advantage of live-tissue intrinsic emission imaging, the researchers say, is that the scans can be made through the surface of intact organs or body systems. By comparison, histopathology studies generally are performed on biopsy samples removed from subjects, then "fixed" or embalmed and stained with labeling chemicals, which involves extended time delays.The Cornell-Harvard team incorporated a technology into the new imaging procedure called multiphoton microscopy, invented in 1989 by Watt W. Webb, Cornell's S.B. Eckert Professor of Engineering and professor of applied physics, and Winfried Denk, now director of the Max-Planck-Institut für Medizinische Forschung Biomedizinische Optik, Germany.
Biological imaging technology has already gone thru dramatic advances with the development of CAT scanners, MRI scanners, and other scanning technologies. The general trend toward easier and more detailed 3 dimensional imaging of living biological tissue shows no sign of stopping.
The use of multiphoton microscopy can be enhanced by use of quantum dots. The use of shock waves in photonic crystals to shift light frequencies may provide a useful method to produce the light needed for this kind of imaging.
What I think is kinda funny about these advances is that they are starting to make science fiction TV shows set a few centuries into the future look backward in comparison. Dr. McCoy's medical tricorder has not yet been equalled. But can anyone doubt that within a few decades real medical science will be far more advanced than 22nd, 23rd, and 24th century fictional Star Trek Federation technology?
|Share |||Randall Parker, 2003 June 12 03:44 PM Biotech Assay Tools|