Tomey UD-8000 - How to Calculate Axial Length Using the Biometry Function; Phakic Eye

■ 4-14
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
222
vitvitInsInsacdacd
tVtVtV
L
⋅
+
⋅
+
⋅
=
2
tV
L
⋅
=
acd
V
Ins
V
vit
V
acd
t
Ins
t
vit
t