■
4-12
4.1.7 Shammas-PL formula
■
This formula is for POST LASIK.
1. Implanted IOL power (D) for emmentropization
1336
05.00125.1
1
)05.0(231.0
1336
C
Kc
CLL
Pemme
2. Implanted IOL power (D) for ametropia
1336
05.00125.1
1
05.0231.0
1336
C
REFcKc
CLL
Pamet
3. Predicted refractive power after surgery (D)
Kc
CLcCPLc
CLcP
REFciol
05.005.01336
05.0133613360125.1
L : Axial length (mm)
C = pACD = (0.5835 × A) – 64.40
A : A-Constant
Kc = 1.14 × K – 6.8
K : Average corneal refractive power (D)
= (K1 + K2)/2
r : Radius of corneal curvature (mm)
= {(KI –1) × 1000}/K
KI : Cornea equivalent refractive index
REFc : Refractive power at corneal refractive surface
REF : Target Ref. after surgery (D)
P : Implanted IOL power (D)
Lc = L–0.1(L–23)
VD : Vertex distance (mm)
= 12