Tomey UD-600, Operator'S Manual

Page: 199 / 262

4-7
4.3.3 HOLLADAY
1. Implanted IOL power (D)
2. Post surgery expected refractive power (D)
Where,
X:
na·r-L2(nc-1)
Y: na·r-(nc-1)(C2+SF)
Q: L2-C2-SF
na: Aqueous humor and vitreous refractive index
=1.336
nc: Corneal refractive index
=4/3
L: Axial length (mm)
r: Average corneal curvature (mm)
=337.5/K
K: Average corneal refractive power (D)
=(K1+K2)/2
SF: Distance from iris to the optical center of implanted
IOL (mm)
REF: Post surgery expected refractive power (D)
V:
Vertex distance (mm)
=12
P: Implanted IOL power (D)
L2: Corrected axial length (mm)
=L+0.2
C2: Anatomical distance between ACD/corneal peak and
iris (mm)
=0.56+Rag - Rag
2 -AG 2 /4
r
<
7
→
Rag=7
r 7
→
Rag= r
AG=12.5L/23.45
AG
>
13.5
→
AG=13.5
4.3 IOL power calculation
1000na{X-0.001REF(V·X+L2·r)}
P = ——————————————————
(L2-C2-SF)[Y-0.001REF{V·Y+r(C2+SF)}]
1000na·X-P·Q·Y
P
amme
= —————————————————
na(V·X+L2·r)-0.001P·Q{V·Y+r(C2+SF)}