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

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 166 KB
• Volume: 36
• Category: Article
• ISSN: 0196-8092
• DOI: 10.1002/lsm.20162

✦ Synopsis

Background and Objectives: The use of laser speckle imaging for the observation of blood velocities was investigated. Study Design/Materials and Methods: Measurements of blood velocity in animals and human subjects were obtained using laser speckle imaging. The tissue was illuminated with a low power HeNe laser and imaged with a monochrome CCD camera. Animal measurements were performed on skin tissue that was treated with vasodilators and vasoconstrictors, and on surgically cut flaps where blood flow was partially and then totally occluded. Blood velocity measurements were also performed on the tongue, retina and iris. The human measurements included skin tissue that was treated with a vasodilator (nitroglycerine), tissue exposed to hot and cold treatments, and the tongue. Operating room measurements of flaps before and after grafting were also obtained as were subsequent post operative measurements. Laser Doppler measurements were performed for comparison.

Results: Blood velocity was obtained from the analysis of laser speckle contrast. The accuracy of velocity retrieval improves when optimum exposure time is used. Conclusions: Laser speckle imaging provides realtime, noncontact monitoring of tissue blood velocity in vivo. The technique can be used to monitor both gradual and sudden changes in tissue perfusion.