OPTIKON BIOLINE, Инструкция по установке и эксплуатации, Страница: 26 / 42

BIOLINE Manual for installation and use
OPTIKON 2000
•
The moving A-SCAN graphic allows the operator to check that the probe is
correctly lined up during the examination. After the image is automatically
frozen the A-scan graphic helps to evaluate the quality and accuracy of the
measurement. Two arrow-shaped symbols known as markers indicate the
base of the corneal peak and that of the retina respectively, from which the
axial length of the eye is calculated.
•
The length of the anterior chamber (AC) the thickness of the lens (LNS) and
the axial length (AXL).
•
If the mode is manual (MODE
=
MAN.GATE) or the eye is aphakic, only the
axial length AXL is indicated. All the measurements are in millimetres.
•
The average of the measurements stored (up to 5). This is indicated in larger
figures; under the average axial length the number of averaged measurements
(AVG = nSamples with n from 1 to 5) is indicated. It is advisable to take from
three to five measurements per patient. The accuracy of the measurements is
deduced from the standard deviation (indicated as +-x.xx in small figures, to
the right of the average). The standard deviation can be indicated vocally if the
mode PRMT:VOX is selected.
The standard deviation of a series of accurate measurements must not exceed
+/-0.3 mm. It is possible to increase the accuracy of the average by taking new
measurements. If 5 measurements have already been taken (maximum
number), the new measurement automatically replaces the worst of those in
the memory.
8.3 A-SCAN KEY FUNCTIONS
In order to simplify the use of the instrument very few keys have been used. Some of
these are reserved for the most frequent operations. In the A-scan session the keys
have the following functions:
•
CLEAR
Clears the A-scan graphic and the measurement displayed on the
screen. By pressing the CLEAR key again all the measurements in the
memory are cleared; the latter operation generally precedes the examination
of the other eye or that of a new patient.
NOTE: It is possible to recover measurements cancelled by mistake. To do this turn
the instrument off immediately after any cancellation and then turn it back on.
•
ASCAN
...Starts or interrupts the acquisition of the A-scan. The same function
can be carried out using the optional footswitch. The two modes are indicated
Code 141002EN 8-2 26.10.05 Rev.0