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Ultrafast Time-resolved Near-IR Stimulated Raman Measurements of Functional π-conjugate Systems
Published on: February 10, 2020
A compact time-resolved system for near infrared spectroscopy based on wavelength space multiplexing
Rebecca Re1, Davide Contini, Matteo Caffini
1Dipartimento di Fisica, Politecnico di Milano, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy. rebecca.re@mail.polimi.it
The Review of Scientific Instruments
|December 8, 2010
Summary
We developed a compact near-infrared spectroscopy system for muscle and brain imaging. This novel wavelength multiplexing approach enhances signal quality for better in vivo measurements.
Area of Science:
- Biomedical Optics
- Spectroscopy
- Instrumentation
Background:
- Near-infrared spectroscopy (NIRS) is valuable for non-invasive monitoring of muscle and brain oxygenation.
- Existing NIRS systems face challenges with signal-to-noise ratio and wavelength cross-talk.
- Compact and efficient instrumentation is needed for broader clinical and research applications.
Purpose of the Study:
- To design and develop a compact, dual-wavelength, dual-channel time-resolved NIRS system.
- To implement an innovative wavelength space multiplexing technique for improved data acquisition.
- To validate the system's performance using phantom and in vivo studies.
Main Methods:
- Utilized pulsed diode lasers and photomultipliers with time-correlated single photon counting.
- Implemented wavelength space multiplexing using an optical 2x2 switch for alternating laser injection.
- Characterized instrument performance (linearity, stability, noise, reproducibility) with tissue phantoms.
- Conducted preliminary in vivo measurements on human muscle and brain.
Main Results:
- The wavelength space multiplexing approach demonstrated improved signal-to-noise ratio and reduced wavelength cross-talk compared to time multiplexing.
- Instrument characterization showed good linearity, stability, noise performance, and reproducibility.
- Successful preliminary in vivo measurements were obtained from muscle during cuff occlusion and brain during motor cortex activation.
Conclusions:
- The developed compact dual-wavelength NIRS system is effective for muscle and brain studies.
- Wavelength space multiplexing offers significant advantages for time-resolved NIRS acquisition.
- The system shows promise for non-invasive physiological monitoring in clinical and research settings.
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