Zeiss VISUCAM C, Руководство пользователя

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Operation
000000-1253-546 VISUCAM C 31.07.2003
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Adjusting the instrument to the patient by infrared
observation
The whole capture process must take place in a darkened room to
achieve natural dilation of the patient’s pupils.
Preparing the patient:
Dilation of the patient’s pupils by use of drugs is not necessary. The
Infrared button in the software is activated .
•
Have the patient sit down and adjust the height of the table. Let the
patient rest with the chin on the chinrest and with the forehead
against the forehead strap. Turn knurled sleeve (
6 , Fig. 3) until the
patient’s eye is level with the red eye-level marks on the uprights
(
3 , Fig. 3) of the headrest.
•
Fit the cap ( 1 , Fig. 1) over the external fixation device and direct the
smaller hole in the cap towards the patient.
•
Position the instrument about 10 to 15 cm in front of the eye to be
examined.
•
Darken the treatment room more to allow maximum possible dilation
of the patient’s pupils.
•
Have the patient lean slightly forward so that forehead and chin are
firmly positioned.
•
Adjust your seat, if necessary.
Note
Since reflections cannot be judged correctly in infrared light, the
position and focus of the light ring is immensely important (sharp
focus is indicated by a narrow ring).
Adjusting the VISUCAM C:
•
Check whether the infrared light is active.
•
With the lens cap still attached, move the instrument base laterally to
align it to either left or right eye.
•
Now, remove the lens cap.
•
Have the patient look either with the non-examined eye to the
external fixation light or with the eye to be examined to the target of
the internal fixation device.
•
Move the instrument base slowly towards the eye until the patient’s
eye is visible with the light ring in the survey window (
8 , Fig. 12)
(distance between front lens and eye approx. 4 cm).
•
Position the light ring sharply and centrally in the patient’s pupil ( 8 ,
Fig. 2) by moving the joystick ( 9 , Fig. 12).
•
Turn the focusing control ( 11 , Fig. 2) to focus onto the fundus. If
necessary, adapt the brightness with the control knob ( 9 , Fig. 2) to
clearly show the vessels of the retina.
•
With the image angle set at 25° the image capture can be triggered
with the button on the joystick.