Fast and Non-Invasive Medical Diagnostic Using Mid Infrared Sensor: The AMNIFIR Project
Résumé
Aim Amnifir project, part of the ANR TECSAN program, intended to assess the capabilities of a new Mid InfraRed spectroscopy (MIR) device. It used a simple fiber optic sampling method: Fiber Evanescent Wave Spectroscopy (FEWS), which makes Point of Care applications possible and delivers a result within a few minutes. Material and method To investigate the technology application range, different biological media (tissues, fluids) as well as pathologies (chronic, cancerous) were considered during the project. We present work on one cancer diagnostic, measuring tissues (colorectal polyp examination), and one chronic disease diagnostic, using a fluid sample (Non-Alcoholic SteatoHepatitis (NASH) markers in serum). We used specific FEWS sensors for both cases, made of chalcogenide infrared glass fiber, as well as proper signal analysis algorithm that first selected spectra area of interest by genetic algorithm, then discriminated the healthy population from the sick one by linear discriminant analysis. Results Measurements using liquid samples provide very encouraging results for NASH identification. On other hand, fiber sensor proved more difficult to use on tissues, as the fiber mechanical resistance appeared too low to sustain a contact with the hardest polyps. Conclusions AMNIFIR project demonstrated capabilities of MIR FEWS for medical diagnostic using biological fluids, leading to recruitments of further cohorts of NASH and other hepatic disorders patients. Mechanical resistance of fiber needs to be improved for tissues diagnostics