Abstract
Purpose :
To measure the irradiance and spectral content of the light source from a surgical operating microscope at various illumination settings. This information is then used to determine the retinal blue light hazard as a function of exposure time for both the phakic and aphakic cases.
Methods :
A Leica M501 surgical microscope is being used as the testing apparatus. The setup consists of a 2 inch integrating sphere capable of absolute flux measurements placed below the focal plane of the surgical microscope. The integrating sphere is outfitted with an 8 mm aperture to simulate the dilated pupil. The spectral flux was measured at ten different illumination levels over the wavelength range 300nm to 900nm and converted to spectral radiance. These values are then weighted against blue light photochemical, aphakic photochemical, and thermal damage thresholds of the eye to determine safe exposure times.
Results :
The figure below shows the calculated spectral radiance for the various illumination settings. The microscope provides a strong attenuation below wavelengths of 400nm limiting the risk of ultraviolet and blue light hazards.
Conclusions :
The above procedures show that the Leica M501 surgical microscope has a low risk of damaging the eye during the length of common surgeries.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.