Using a laser-based technique that images the fabric of deep layers of skin, physicists and medical researchers have noninvasively measured the level of damage to the skin from sun exposure and aging. The technique measures relative amounts of collagen and elastin by a single factor. Previously, separate imaging techniques for each of these substances had only been tested on tissue extracted from live patients. In the new paper, researchers at Friedrich Schiller University (Jena, Germany), the Fraunhofer Institute of Biomedical Technology (St. Ingbert, Germany), and JenLab (Jena, Germany) tested a combined technique directly on the forearms of 18 patients.
The two methods combined in the imaging technique use the ability of femtosecond pulses of IR (820 nm) light to stimulate tissues to emit light at shorter wavelengths-blue in the case of collagen and green in the case of elastin. Although the technique is still at the experimental stage, the authors hope that someday it could become useful in studying skin diseases that affect the collagen structure, including scleroderma and some chronic complications of graft-versus-host disease. Contact Martin Johannes Koehler at [email protected].