© Haag-Streit AG, CH-3098 Koeniz, Switzerland
1500.7220055.04030
according to IEC 60825-1.
.. Measured variables
Measurement ranges are based on the standard setting of the device
for automatic measurements and analysis ('Phakic' measurement
mode). Repeatability was determined by statistical analysis of variance
(ANOVA) of repeated measurements. The method permitted separa-
tion of systematic influences like subject or eye (within subject) and
effects of random error (residuals). Repeatability (denoted as SD
repeat
in Tab. 1 and 2) was calculated as square root of the residual error.
... Corneal thickness (CT)
Measurement range:
300 – 800 μm
Display resolution:
1 μm
In-vivo repeatability (1.SD):
±2.3 µm
... Anterior chamber depth (ACD)
Measurement range:
1.5 - 5.5 mm
Display resolution:
0.01mm
In-vivo repeatability (1.SD):
±0.04 mm
... Lens thickness (LT)
Measurement range:
0.5 – 6.5 mm
Display resolution:
0.01 mm
In-vivo repeatability (1.SD):
±0.08 mm
... Eye length (AL)
Measurement range:
14 – 32 mm
Display resolution:
0.01 mm
In-vivo repeatability (1.SD):
±0.035 mm
... Keratometry (R)
Measurement range for radius :
5 – 10.5 mm
Display resolution:
0.01 mm
In-vivo repeatability (1.SD):
±0.03 mm
Measurement range for axis angle:
0-180°
Display resolution:
1°
In-vivo repeatability (1.SD):
±11°
... White-to-white distance (WTW)
Measurement range:
7 - 16 mm
Display resolution:
0.01 mm
In-vivo repeatability (1.SD):
±0.04 mm
... Pupillometry
Measurement range :
2 – 13 mm
Display resolution:
0.01 m
Data for subjects with a complete set of 5 repeat measure-
ments for both eyes were included to derive Mean
grand
,
SD
repeat
and the coefficient of variation (CV) shown in Tab. 1 and 2.
For each measurement parameter the standard deviations of each
set of 5 replicate measurements were found to be nearly constant
over the range of mean results. This finding confirms that the indi-
cation of one single standard deviation value for each measurement
parameter is a valid approach.
... Data source
In-vivo repeatabilities (1.SD) have been derived from data of a clinical
study. This study was designed and accomplished as a prospective,
non-randomized single site comparison study.
The approved investigational plan included in study stage 1 measure-
ments of axial length (AL), central corneal thickness (CT), anterior
chamber depth (ACD), central lens thickness (LT), mean corneal
radius (R), and axis of the flat meridian. In study stage 2 the white-
to-white distance was measured. A total of 144 eyes of 80 subjects
were included in study stage 1 and a total of 40 eyes of 20 subjects
in study stage 2.
Subjects with different conditions of the anterior and posterior seg-
ment of the eye (cataract in different stages, pseudophakia with dif-
ferent IOLs, aphakia, silicone-oil fill) and healthy eyes were included
in this clinical study. Data were analyzed for all eyes (see Tab. 1) and
a subgroup of special eyes (see Tab. 2) with a complete set of 5 re-
peat measurements on both eyes of each subject. The special eyes
group included eyes with one or more of the following conditions:
pseudophakia, aphakia and silicone-oil fill.
n:
Anzahl der Probanden oder
Augen
Mean
:Mittlerer Wert aller
Ergebnisse aller Augen
SD
: Wiederholte
Standardabweichung
CV:
Variationskoeffizient
SD:
Standardabweichung
grand
repeat
n:
Nombre de sujets ou des
yeux
Mean
:Valeur moyenne de tous
les résultats de tous les
yeux
SD
: Écart standard répété
CV:
Coefficient de variation
SD:
Écart standard
grand
repeat
n:
Number of subjects /
number of eyes
Mean
:Overall mean of all
replicate measurements
results on all eyes
SD
: Square root of the residual
error (Repeatability
standard deviation)
CV:
Coefficient of variation
SD:
Standard deviation
grand
repeat
AL: Axiale Länge
CT: Hornhautdicke
ACD: Vorderkammertiefe
LT:
Linsendicke
R:
Hornhaut-Krümmungsradius
Axis: Achse des flachen Meridian
WTW: Weiss-Weiss-Abstand
AL: Longueur axiale
CT: Épaisseur de la cornée
ACD: Profondeur de la chambre
antérieure
LT:
Épaisseur de la lentille
R:
Rayon de courbure de la
cornée
Axis: Axe du méridien plat
WTW: Écart blanc-blanc
AL: Axial length
CT: Corneal thickness
ACD: Anterior chamber depth
LT:
Lens thickness
R:
Corneal radius of curvature
Axis: Axis of flat meridian
WTW: White-to-white distance
AL [mm]
CT [µm]
R [mm]
Axis [°]
10 / 20
11 / 22
5 / 10
3 / 6
24.087
564.4
7.75
80
0.056
2.8
0.03
13
0.00234
0.00496
0.00333
0.16092
AL [mm]
CT [µm]
ACD [mm]
LT [mm]
R [mm]
Axis [°]
WTW [mm]
45 / 90
53 / 106
34 / 68
27 / 54
34 / 68
27 / 54
9 / 18
23.973
557.1
3.19
4.56
7.67
72
12.27
0.035
2.3
0.04
0.08
0.03
11
0.04
0.00145
0.00407
0.01220
0.01784
0.00396
0.14191
0.00337
[unit]
n
Mean
grand
SD
repeat
CV
[unit]
n
Mean
grand
SD
repeat
CV
Tab. 1: Alle Augen / Tous les yeux / All Eyes
Tab. 2: Spezielle Augen / Yeux spéciaux / Special Eyes
