Zeiss OPMI 1FR XY, Инструкция по эксплуатации

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Safety
G-30-1416-en OPMI® 1FR XY Surgical Microscope on S7 Floor Stand Issue 4.0
Printed on 14. 11. 2007
In the following, comments on these aspects are given and a description
of how Carl Zeiss, as a manufacturer, makes allowance for them in its in-
struments.
Illumination characteristics (spectral composition)
Studies on exposure of the eye to light of varying spectral composition
date back to the early 1950s. These studies suggest that the potential
hazard of phototoxic injury to the patient's retina can be reduced by
blocking out the blue and ultraviolet light below a wavelength of 475 nm.
Carl Zeiss provides a GG 475 retina protection filter for surgical micro-
scopes recommended for use in ophthalmic surgery. This reduces not
only the light exposure of the patient's eye, but also that of the surgeon's.
It should be noted in this context that the use of filters inevitably leads to
a change in the color of the light. The surgeon may therefore have to get
used to the changed appearance of anatomical structures.
Intensity of illumination
The majority of researchers suggest that the surgeon should use the
lowest light intensity necessary to guarantee good viewing during sur-
gery.
Carl Zeiss has addressed this concern by providing a device for continu-
ously varying the brightness of the light source. This permits the surgeon
to optimally adapt the light intensity at the patient's eye to the conditions
existing in each case. Carl Zeiss strongly discourages the use of xenon or
other high-intensity light sources in ophthalmology.
Angle of illumination
A number of publications suggest that the microscope should be tilted to
reduce the exposure of the macula to direct illumination.
Carl Zeiss ophthalmic surgical microscopes are therefore equipped with
the following:
– Tilting mechanism for the microscope body
– Oblique illumination with brightness control
Focus of the light source
Studies show that injuries are likely to occur if the filament of the light
source is imaged on the patient's retina. The peak intensity of a filament
is considerably higher than the peak intensity of an even and extended
light source such as a fiber guide.