Zeiss OPMI Lumera i on floor stand, Instructions For Use Manual

Page: 24 / 178

Version 9.2
Page 24 G-30-1720-en
Safety measures OPMI Lumera
®
i on floor stand
Duration of exposure to light
According to some publications, the eye should not be exposed to the light
source for more than a few minutes. In all surgical cases, the retinal exposure
time to light depends on the type and duration of the procedure and possible
case complications. It is therefore recommended in ophthalmic surgery to
keep the illumination intensity as low as possible, or to use a device which
prevents the light from entering through the patient’s pupil. It is also recom-
mended to make sure that the patient’s eye is not additionally exposed to the
light of surrounding light sources.
This problem has been solved by ZEISS by the use of a retina protection filter
(blue barrier filter) and a retina protection cover that can be swung into the
surgical microscope’s illumination beam path.
Brightness setting The brightness control scale of the ZEISS systems has a linear structure
with values ranging from 5 % … 100 %. The stipulations of standard
DIN EN ISO 15004-2:2007 result in maximum radiation exposure times for
the different illumination configurations as specified in the table “Maximum
radiation exposure times” (see page 26).
The maximum brightness of the lamps decreases in the course of time as a
result of normal wear.
Phototoxic
risk factors
The microscope light source — like any bright light source — may present a
potential hazard to the patient’s eye both in the form of immediately visible
thermal damage to the retina as well as phototoxic chemical reactions which
may lead to photoretinitis. The factors which play an important role in deter-
mining the phototoxic risk are:
– Lamp brightness
– Spectral distribution of the light (UV and blue light is more dangerous than
light of longer wavelengths)
– Duration of direct exposure
– Pupil size
– Clarity of ocular media (infants and young children, for example,
may be at a higher risk)
– Condition of the eye: aphakic and pseudo-aphakic eyes with IOLs of a
material without UV/blue filter are at a higher risk
– Previous exposure to bright light such as retinal photography, especially
within the last 24 hours