Optical spectroscopy has proven to be a very powerful method in bio-photonic technologies. The multimodal use of different spectroscopic techniques makes this approach especially promising for medical diagnosis. For preventive diagnostics, there is great interest to use as much information as possible regarding the tissue before, during and after treatment. Spectroscopy can non-invasively assess morphologic and biochemical changes, thereby ensuring pre-treatment identification of tissue type and discrimination between healthy and diseased tissue. It is ideally suited for molecule-specific recognition of biomarkers and tracking treatment progress.
The study is focused on the research, development, design and tests of a novel system based on Raman, Near-Infrared (NIR) and Fluorescence spectroscopy merged with temperature measurement for diagnosis of different diseases, i.e. cancer. Combination of all these methods together with multivariate signal and data processing makes the device universal and leads to an increase of diagnostic accuracy, sensitivity and specificity. The compact, cost-effective, portable and modular design is the main advantage of the combined spectroscopic system.
Overall dimensions of the system measure only 30×23×20 cubic centimeters. It consists of 3 spectrometers (Raman, Fluorescence and NIR) and 3 light sources (785 nm laser for Raman, 532 nm laser for Fluorescence and halogen lamp for NIR) for spectroscopic methods plus a pyrometric temperature sensor. All modules are equipped with specially designed fiber-optic probes (SiO2 fibers for the spectroscopy and PIR fibers for the temperature sensor) for increased flexibility. The software is realized by a personal computer (PC), requiring only one graphical user interface for hardware operation and data processing. This allows measurement and results within seconds. The system may function independently of a PC as a stand-alone tool, using an installed microcontroller, which permits the processing functions.
System modules were tested separately and together on different types of chicken, bovine and porcine tissue. Furthermore, several ex vivo biopsies of healthy or cancerous human tissue and bio-liquids (serum, plasma, urine) were analyzed. Temperature sensing was tested in real-time, monitoring the local temperature changes seen in laser surgery.