The Measurement of Threshold Temperatures in the Ocular Fundus for Laser-Induced Visible Lesions.

Abstract

Measurements of temperature increases resulting from exposures to argon laser irradiations were made in the eyes of living rhesus monkeys with 10-20 micrometer diameter thermocouples. Using the appearance of an ophthalmoscopically visible lesion as the criterion for damage, the temperature associated with the appearance of a threshold lesion 5 minutes post exposure was determined. Temperature increases at the center of the lesion and at the scans of the thermocouple through the laser image and from ophthalmoscopic measurements of the lesion radius. Temperatures associated with threshold lesions were measured for a number of exposure durations and for image sizes from 100-200 micrometer (half-power diameter). Threshold were acquired for both macular and paramacular (temporal) exposure sites. The average macular threshold temperature increases at beam center were 66.1 C, 29.4 C, 24.1 C, and 19.9 C for exposure durations of .01 second, .1 second, 1 second, and 10 seconds exposure durations.

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Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1976
Accession Number
ADA035057

Entities

People

  • A. J. Welch
  • L. A. Priebe

Organizations

  • University of Texas at Austin

Tags

Communities of Interest

  • Biomedical
  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Absorption
  • Arrhenius Equation
  • Birds
  • Energy
  • Eye
  • Heat Transfer
  • Laser Beams
  • Laser Safety
  • Lasers
  • Light Sources
  • Measurement
  • Medical Personnel
  • Refraction
  • Refractive Index
  • Retina
  • Skull
  • Thermal Conductivity

Fields of Study

  • Physics

Readers

  • Combustion and Flow Dynamics.
  • Pulsed Power and Plasma Physics.
  • Vision Science/Vision Psychology/Cognitive Neuroscience.

Technology Areas

  • Directed Energy
  • Directed Energy - Lasers