BACKGROUND AND OBJECTIVES: Damage to blood and other tissues during laser interventions depends mainly upon absorption of laser radiation by cells. The objective of this work was to evaluate the influence tissue-specific physiological factors on photo-damage thresholds of individual cells: Red blood cells (blood), hepatocytes (liver), and miocytes (heart). STUDY DESIGN/ MATERIALS AND METHODS: Laser-induced damage to individual cells was detected and studied with Laser Load Test (LLT). Probability and thresholds of RBC damage after one laser pulse (532 nm, 10 nanoseconds) were obtained experimentally as functions of physiological conditions. Using in vitro models, we have studied influence of the oxygen level, pH, temperature, and cell heterogeneity on RBC, the inhibition of metabolic activity on miocytes and drug toxicity on hepatocytes. RESULTS: Single laser pulse induced cell lyses through a vapor bubble. The decrease of the O2 level and temperature caused increase of damage thresholds at 532 nm. Deviation of the pH level from neutral to any side caused also the increase of the damage threshold. Inhibition of metabolism of miocytes and toxic damage to hepatocytes also resulted in the increase of the damage threshold. CONCLUSIONS: Resistance of various tissues at cell level against photo-damage significantly depends on physiological properties of cells. A general rule for such dependence is that the better the cell state the lower its threshold for laser-damage.
BACKGROUND AND OBJECTIVES: Damage to blood and other tissues during laser interventions depends mainly upon absorption of laser radiation by cells. The objective of this work was to evaluate the influence tissue-specific physiological factors on photo-damage thresholds of individual cells: Red blood cells (blood), hepatocytes (liver), and miocytes (heart). STUDY DESIGN/ MATERIALS AND METHODS: Laser-induced damage to individual cells was detected and studied with Laser Load Test (LLT). Probability and thresholds of RBC damage after one laser pulse (532 nm, 10 nanoseconds) were obtained experimentally as functions of physiological conditions. Using in vitro models, we have studied influence of the oxygen level, pH, temperature, and cell heterogeneity on RBC, the inhibition of metabolic activity on miocytes and drug toxicity on hepatocytes. RESULTS: Single laser pulse induced cell lyses through a vapor bubble. The decrease of the O2 level and temperature caused increase of damage thresholds at 532 nm. Deviation of the pH level from neutral to any side caused also the increase of the damage threshold. Inhibition of metabolism of miocytes and toxic damage to hepatocytes also resulted in the increase of the damage threshold. CONCLUSIONS: Resistance of various tissues at cell level against photo-damage significantly depends on physiological properties of cells. A general rule for such dependence is that the better the cell state the lower its threshold for laser-damage.
Authors: Ekaterina Y Lukianova-Hleb; Alexander O Oginsky; John S Olson; Dmitri O Lapotko Journal: Lasers Surg Med Date: 2011-02-02 Impact factor: 4.025
Authors: Jun Xia; Guo Li; Lidai Wang; Mohammadreza Nasiriavanaki; Konstantin Maslov; John A Engelbach; Joel R Garbow; Lihong V Wang Journal: Opt Lett Date: 2013-12-15 Impact factor: 3.776