11
DEUTSCH
ENGLISH
FRANÇAIS
ITALIANO
ESPAÑOL
NEDERLANDS
PORTUGUÊS
SVENSKA
DEUTSCH
ENGLISH
FRANÇAIS
ITALIANO
ESPAÑOL
NEDERLANDS
PORTUGUÊS
SVENSKA
© HAAG‑STREIT AG, 3098 Koeniz, Switzerland
–
HS‑Doc. no. 1500.7006000.04220 – 22. Edition / 2016 – 06
5.8 Sources of error
Ocular images
Fluorescein band incorrect
1
‒
2
Wrong distance to patient
3
‒
9
Position too far to the right / left
5
‒
9
Position too high / low
10
‒
14
Incorrect pressure
15
‒
18
Fluorescein band too wide (1)
1
The measuring prism was not dried after cleaning or the eye‑
lids came into contact with the measuring prism during mea‑
surement.
The slit lamp must be pulled back and the measuring prism
dried with a lint-free cloth (e.g., made of cellulose).
Fluorescein band too small (2)
2
The tear fluid dried during the longer-lasting measuring.
Allow the patient to close his eyes a few times and then re-
peat the measurement.
5.8.1 Wrong distance to patient
No semi circular image, only centre line is visible (3)
3
The measuring prism is not coming into contact with the cor‑
nea! If the patient draws his head back slightly, irregular pulsa‑
tions will be caused because the measuring prism is touching
the eye only intermittently. If the patient retreats even further,
the fluorescein rings will disappear completely.
Use a headband if necessary.
Only parts of both oversize semicircles are visible (4)
4
If the slit lamp is pushed too far against the patient, or if the
patient moves toward the slit lamp, the sensor arm will push
against a spring stop. The applanation surface is too large.
The image does not change when the measuring drum is
turned. Pull the slit lamp back until the uniform pulsations
of a correspondingly smaller surface show the correct mea-
suring position and pressure changes immediately cause
applanation surface changes.
5.8.2 Position too far to the right / left
Only part of the upper semicircle (5)
5
Measuring prism not centred on the eye, eye much too far to
the right.
Using the control lever, move the slit lamp to the right.
Whole upper semicircle – part of the lower semicircle (6)
6
Measuring prism not centred on the eye, eye still too far to the
right.
Using the control lever, move the slit lamp to the right.
Whole lower semicircle – part of the upper semicircle (7)
7
Measuring prism not centred on the eye, eye still too far to the
left.
Using the control lever, move the slit lamp to the left.
Only part of the lower semicircle (8)
8
Measuring prism not centred on the eye, eye much too far to
the left.
Using the control lever, move the slit lamp to the left.
01-IFU_AT900-7006000-04220_eng.indd 11
09.06.2016 13:51:01
