Spatial temperature distribution in human hairy and glabrous skin after infrared CO2 laser radiation

Spatial temperature distribution in human hairy and glabrous skin after infrared CO2 laser radiation

BACKGROUND CO2 lasers have been used for several decades as an experimental non-touching pain stimulator. The laser energy is absorbed by the water content in the most superficial layers of the skin. The deeper located nociceptors are activated by passive conduction of heat from superficial to deeper skin layers. METHODS In the current study, a 2D axial finite element model was developed and ...

Stress-Induced Mast Cell Activation in Glabrous and Hairy Skin

Mast cells play a key role in modulation of stress-induced cutaneous inflammation. In this study we investigate the impact of repeated exposure to stress on mast cell degranulation, in both hairy and glabrous skin. Adult male Wistar rats were randomly divided into four groups: Stress 1 day (n = 8), Stress 10 days (n = 7), Stress 21 days (n = 6), and Control (n = 8). Rats in the stress groups we...

Characterization of Nociceptive Behaviors Induced by Formalin in the Glabrous and Hairy Skin of Rats

Introduction: Glabrous skin and hairy skin are innervated by different types of noxious fibers. However, the different nociceptive behaviors induced by formalin, a commonly used model of acute inflammatory pain, have not yet been systematically examined in the glabrous and hairy skin. Methods: In this study, we compared nociceptive behaviors induced by formalin injections (2%, 4%, and 8%) into...

Cutaneous pain and detection thresholds to short CO2 laser pulses in humans: evidence on afferent mechanisms and the influence of varying stimulus conditions.

Pain and detection thresholds to short CO2 laser pulses were studied in healthy human subjects. Pain thresholds were significantly higher than detection thresholds in both hairy and glabrous skin; in the glabrous skin both thresholds were higher in the hairy skin. The range from detection threshold to pain threshold was larger in the glabrous skin. The minimal energy per surface area needed to ...

The Analytical Investigation of Temperature Distribution in Enamel under Er:YAG Laser Radiation