Corneal epithelial injury thresholds for exposures to 1.54 μM radiation-dependence on beam diameter

Russell L. McCally, Jennifer Bonney-Ray, C. Brent Bargeron

Research output: Contribution to journalArticlepeer-review

16 Scopus citations


Corneal epithelial injury thresholds have been determined for exposures to 1.54 μm infrared radiation from an Erbium fiber laser. Thresholds were determined for beam diameters from 0.05 to 0.7 cm for exposures having durations from ∼1 to 100 s and for a fixed beam diameter of 0.1 cm for exposures with durations between 0.036 and 0.26 s. Near-threshold damage appeared within 30 min post-exposure. There was no evidence of latent damage from lesser exposures appearing up to 24-48 h post-exposure. The dependence of the threshold radiant exposures on laser beam diameter for exposures >1 s provides strong evidence supporting a critical temperature damage model. However, the shorter exposures are not in accord with a critical temperature damage model. Thresholds for exposures longer than 1 s are greater than 10 times the maximum permissible exposure (MPE) in ANSI Z-136.5-2000; however, the safety factor decreases to less than 10 for exposures less than 0.1 s with a 0.1-cm-diameter beam.

Original languageEnglish (US)
Pages (from-to)615-624
Number of pages10
JournalHealth physics
Issue number6
StatePublished - Dec 2004


  • Health effects
  • Lasers
  • Nonionizing
  • Radiation
  • Radiation damage

ASJC Scopus subject areas

  • Epidemiology
  • Radiology Nuclear Medicine and imaging
  • Health, Toxicology and Mutagenesis


Dive into the research topics of 'Corneal epithelial injury thresholds for exposures to 1.54 μM radiation-dependence on beam diameter'. Together they form a unique fingerprint.

Cite this