a. Tentukan
berapa astigmat kornea
b. Hitung
BC/power/diameter trial LK RGP yang akan dipasang
Jawaban :
H = 7,88@180 = 337,5 = 42,83D@180 (flat K)
7,88
V = 7,42@90 = 337,5 =
45,49D@90
7,428
KOD = 45,49/42,83@180 =
42,83/45,49@90
Astigmat
kornea = 42,83D – 45,49D
= - 2,66D X 180
= - 2.50D X 180
Secara
Teori ;
Diamater (Ø) untuk HVID
11,5 – 12,5 = 9,5 – 9,7 mm
atau
Diameter
(Ø) TD = HVID – 1,4mm
= 11,5 – 1,4
= 10,1 mm
BOZR/BC untuk TD
(Ø) = 9,2/9,4
Karena astigmat
kornea -2,50 D maka,
BOZR/BC = ⅓ ΔK + Flat K
=
⅓
x 2,66 D + 42,83 D
=
0,89 D + 42,83 D
=
43,72 D => r = 337,5 = 7,719
mm = 7,72 mm
43,72D
·
Trial
= 7,72/-3,25/10,1 mm (atau 9,4 mm - 9,6 mm)
Penentuan BC Trial LK RGP Boston
Astigmat kornea = 2,50D :
- Ø 9,2 BOZR/BC = 0,25 steeper
- Ø 9,6 BOZR/BC = On Flat K
Maka
:
Ø
(9,2mm) trial RGP = 0,25D steeper +
K
= 0,25D + 42,83D
= 43,08D => r = 337,5 = 7,83 mm
43,08D
·
Trial
= 7,83/-3,25/9,2
Ø (9,6mm) trial RGP =
On Flat K
= 7,88
·
Trial
= 7,88/-3,25/9,6
2.
KOD = 8,00/8,20@90, HVID = 14 mm, Refraktive
subyektif S - 6,00 C - 1,00 X 90 ;
a. Tentukan
berapa astigmat kornea
b. Hitung
BC/power/diameter trial LK RGP yang akan dipasang
Jawaban :
H = 8,00@180 = 337,5 = 42,19D@180
8,00
V = 8,20@90 = 337,5 = 41,16D@90 (flat K)
8,20
KOD = 42,19/41,16@90 = 41,16/42,19@180
Astigmat
kornea = 41,16D – 42,19D
= - 1,03D X 90
= - 1,00D X 90
Secara
Teori ;
Diamater (Ø) untuk HVID
= 14 mm(> 12,5mm) = 9,8 – 10,0 mm
atau
Diameter
(Ø) TD = HVID – 1,4mm
= 14,0 – 1,4
= 12,6 mm
BOZR/BC untuk TD
(Ø) = 9,2/9,4
Karena astigmat
kornea -1,00D maka,
BOZR/BC = On Flat K
=
8,20 mm
Power (D) = D
=
-6,00
= -6,00 = -6,00
1 - (VD x D) 1 - (12mm x D) 1 - (0,012m x -6,00D) 1 - (-0,072)
= -6,00 = -6,00 = - 5,597 D = -5,50 D
1 + 0,072 1,0072
·
Trial
= 8,20/-5,50/12,6 mm (atau 9,8 mm – 10,0 mm)
Penentuan BC Trial LK RGP Boston
Astigmat kornea = - 1,00D - Ø 9,2 BOZR/BC = 0,25 flatter
-
Ø 9,6 BOZR/BC = 0,50 flatter
Maka
:
Ø
(9,2mm) trial RGP = 0,25D flatter +
K
= 0,25D + 41,16D
= 41,41D => r = 337,5 = 8,15
mm
41,41D
·
Trial
= 8,15/-5,50/9,2
Ø (9,6mm) trial RGP =
0,50D flatter + K
= 0,50D + 41,16D
= 41,66D => r = 337,5
= 8,10
mm
41,66D
·
Trial
= 8,10/-5,50/9,6
