Basic science: The cutting edge in optical diagnostics and therapeutics of tissues and cells

• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 155 KB
• Volume: 38
• Category: Article
• ISSN: 0196-8092
• DOI: 10.1002/lsm.20312

✦ Synopsis

Background and Objectives: Optical Clearing Agents (OCAs) have been shown to increase depth penetration within turbid tissue. OCAs may be advantageous for light-based diagnostic techniques for epithelial pre-cancer detection. Previous studies have quantified the effects of OCAs on tissue optical properties in vitro. This study quantified the effect of two commonly used OCAs, glycerol and dimethyl sulfoxide (DMSO) on the absorption and scattering properties of the in vivo hamster cheek pouch, which is a model of stratified squamous epithelial tissue. Study Design/Materials and Methods: Diffuse reflectance spectra between 400-460 nm were obtained from both cheeks of 12 hamsters before and after immersion in DMSO, glycerol or a phosphate buffer saline (PBS) control for 20 minutes. A Monte Carlo model of diffuse reflectance was utilized to derive the reduced scattering coefficient, hemoglobin concentration and total hemoglobin saturation of the tissue. Results: DMSO significantly reduces the reduced scattering coefficient by 12.54 cm À1 , the total hemoglobin concentration by 15% and hemoglobin saturation by 77.48 mM. Glycerol significantly increased the total hemoglobin content by 116.11 mM. Glycerol also decreased the reduced scattering coefficient by 5.81 cm À1 , but this value was not statistically significant. Conclusions: DMSO and glycerol act upon tissue in different ways shown by the change in the optical properties. This variability suggests that OCAs should be investigated separately for a given target tissue.