Tomey UD-800 User Manual

■ 4-16
4.2 How to calculate axial length using the biometry function
4.2.1 Phakic eye
The axial length measurement is obtained using the following
formulae.
<When using the average acoustic velocity>
L : Axial length measurement
V : Average acoustic velocity for axial
length
t : Measurement time
<When using the divisional acoustic velocity>
L : Axial length measurement
: Anterior chamber depth acoustic
velocity
: Crystal lens acoustic velocity
: Vitreous acoustic velocity
: Time for measuring anterior chamber
death
: Time for measuring crystal lens
: Time for measuring a vitreous
4.2.2 Dense cataract eye
Take the axial length measurement in the same manner as
when using the average acoustic velocity for a phakic eye.
4.2.3 Aphakic eye
Take the axial length measurement in the same manner as when
using the average acoustic velocity for a phakic eye.
4.2.4 IOL eye
[Default setting for acoustic velocity at delivery (changeable)]
- IOL acoustic velocity (reference)
Acrylic : 2,200m/s
Silicone : 1,049m/s
PMMA : 2,718m/s
2
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Tomey UD-800 Specifications

General

Brand	Tomey
Model	UD-800
Category	Measuring Instruments
Language	English