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Variation of fluorescence in tissue with temperature
Raiyan T Zaman1, Narasimhan Rajaram, Alex Walsh
1Department of Biomedical Engineering, The University of Texas at Austin, Austin, Texas 78712-0238, USA. raiyan_zaman@yahoo.com
Lasers in Surgery and Medicine
|January 22, 2011
Summary
Cooling tissue increases fluorescence intensity, with consistent results observed between in vivo and in vitro measurements. This finding holds true across various tissues and temperatures, offering insights into optical properties.
Area of Science:
- Biomedical Optics
- Photonic Technologies
- Tissue Spectroscopy
Background:
- Previous research indicated reduced tissue fluorescence with elevated temperatures.
- In vitro and in vivo studies previously explored temperature effects on fluorescence intensity.
Purpose of the Study:
- To investigate the relationship between tissue temperature and fluorescence intensity, starting from 14°C.
- To compare in vivo and in vitro measurements for consistency in temperature-dependent fluorescence.
- To characterize temperature effects on tissue auto-fluorescence using a noninvasive system.
Main Methods:
- A fiber optic-based noninvasive system was employed for measurements.
- Auto-fluorescence spectra were recorded from hamster dorsal skin (in vivo) and pig eye tissues (in vitro) across a temperature range of 14-42°C.
- A pulsed nitrogen laser excited fluorescence, with data sampled every 1-2 minutes.
Main Results:
- Fluorescence intensity decreased consistently as tissue temperature rose from 14°C to 42°C.
- Both in vivo and in vitro tissue samples exhibited this inverse relationship between temperature and fluorescence.
- A spectral shift around 450 nm was noted, attributed to tissue absorption.
Conclusions:
- Decreasing tissue temperature enhances fluorescence intensity in vivo.
- In vitro experimental results align with in vivo findings, confirming consistency.
- The study validates the temperature-dependent nature of tissue fluorescence.
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