IOL Calculation Quandaries
1
Case #1
2
• PPLOV OU 10/2012:• OD -6.50 +1.00 x 170
20/30 (BAT 20/70)• OS -13.75 +0.50 x 170
20/40 (BAT 20/80)• Milky NSC OS > OD
(“Myopic cataracts”)
• 59-y/o ♂ w/ h/o:• RD OS s/p SB• Zoster keratitis/
trabeculitis s/p tube shunt OD
IOL Calcs - Lenstar• Axial length:
• OD 27.32 mm• OS 29.57 mm
• Auto-keratometry:• OD 42.29/43.00 @ 159
• Avg 42.64• OS 42.46/42.77 @ 139
• Avg 42.61
• IOL = SN60WF:• OD 11.0D → SE -0.43D• OS 5.0D → SE -0.41D 3
}Δ 2.25
IOL Calcs - IOLMaster• Axial length:
• OD 27.25 mm• OS 29.50 mm
• Auto-keratometry:• OD 42.29/43.21 @ 150
• Avg 42.75• OS 42.67/42.83 @ 173
• Avg 42.75
• IOL = SN60WF:• OD 11.0D → SE -0.47D• OS 5.0D → SE -0.45D 4
Are we good?
}Δ 2.25
Long Eyes• Standard calcs result in
hyperopic errors • Adjusted axial length:
• Holladay 1 formula• New axial lengths:
• OD 26.85 mm (from 27.25 mm)
• OS 28.72 mm (from 29.5 mm)
• IOL = SN60WF:• OD 12.0D → SE -0.34D• OS 6.5D → SE -0.17D 5
ALADJ = (0.8289 * ALIOLM) + 4.2663
Post-Op UCVA 20/20 OU
*Wang L, et al. J Cataract Refract Surg 2011; 37(11):2018-2027
Case #2
6
• PPLOV & Monocular Diplopia OU 11/2012:• OD +1.25 +1.00 x 025
20/40- (BAT 20/70)• OS +1.00 +0.25 x 010
20/50 (BAT 20/80)• Nuclear & cortical
cataracts OU
• 68-y/o ♂ w/ Fuch’s s/p DSAEK OU:• OS 2005, OD 2006• Post-Op BCVA 20/20
OU
IOL Calcs - Lenstar• Axial length:
• OD 24.02 mm
• OS 24.03 mm
• Auto-keratometry:• OD 41.56/42.68 @ 54
• Avg 42.12
• OS 42.08/43.16 @ 131
• Avg 42.62
7
IOL Calcs - IOLMaster• Axial length:
• OD 23.99 mm
• OS 24.01 mm
• Auto-keratometry:• OD 41.67/42.72 @ 57
• Avg 42.20
• OS 42.03/43.27 @ 121
• Avg 42.65
8
What about the DSAEK graft?
9
Atlas Sim-K
10
Atlas Sim-K
Galilei TCP
11
Galilei TCP
12
13
Optovue RTVue NCP
14
Optovue RTVue NCP
IOL Calculations - Holladay 1
15
Keratometry Avg K (D) IOL Power (D)SN60WF
Target Refraction (D)
Lenstar
IOLMaster
Galilei TCP
RTVue NCP
42.62 22.5 -1.20
42.65 22.5 -1.33
39.55 24.5 -0.18
41.56 22.5 -0.33
OS - First
Implanted IOL = SN60WF 22.5D: UCVA 20/20- (MR -0.50 +0.75 155 20/20+)
}} 16
IOL Calculations - Holladay 1
Keratometry Avg K (D) IOL Power (D)SN60WF
Target Refraction (D)
Lenstar
IOLMaster
Galilei TCP
RTVue NCP
42.12 23.5 -1.47
42.20 23.0 -1.27
39.69 24.5 -0.27
40.43 24.0 -0.43
OD - Second
Implanted IOL = SN60WF 24.0D (tight suture): BCVA 20/20 (-1.25 +1.75 x030, SE = -0.37)
}}
IOL Calculation Quandaries
17