Official ESCRS | European Society of Cataract & Refractive Surgeons
Copenhagen 2016 Registration Programme Exhibitor Information Virtual Exhibition Satellite Meetings Glaucoma Day 2016 Hotel Star Alliance

10 - 14 Sept. 2016, Bella Center, Copenhagen, Denmark

This Meeting has been awarded 27 CME credits


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Intraocular lens power calculation for eyes with high and low average keratometry readings: a comparison between various formulas

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Session Details

Session Title: IOL Power Calculations

Session Date/Time: Sunday 11/09/2016 | 16:00-18:00

Paper Time: 17:26

Venue: Hall C2

First Author: : O.Reitblat ISRAEL

Co Author(s): :    A. Levy   G. Kleinmann   A. Abulafia   E. Assia           

Abstract Details


To compare the accuracy of different intraocular lens (IOL) power calculation formulas for eyes with average keratometry (k) readings greater than 46.00 diopters (D) and lower than 42.00D.


Ein-Tal Eye Center, Tel-Aviv, Israel


Consecutive cases of eyes having cataract extraction surgery with steep and flat preoperative corneal curvatures (K>46.00D and K<42.00D, respectively) with the Lenstar-LS900 device were enrolled. Refractive prediction errors for the Barrett Universal II, Haigis, Hoffer Q, Holladay 1, Olsen and SRK/T formulas were compared. Optimized K values for the SRK/T formula were back-calculated for each group. Validation was performed using an additional data set.


102 eyes (54, K>46.00D; 48, K<42.00D) were evaluated. For K readings over 46.00D, a myopic error was noted in calculations with the SRK/T formula (-0.33D, p<0.001) and a hyperopic error using the Olsen’s C-constant (0.23D, p<0.001). The percentage of eyes with an absolute error of ≤0.50D ranged from 59.35% (SRK/T) to 79.63% (Olsen A-constant). For corneas with a dioptric power below 42.00D, myopic errors were seen using the Hoffer Q, Haigis and Olsen-C formulas (-0.32D, p=0.015, -0.28D, p<0.001 and -0.10D, p=0.049, respectively) and a hyperopic error using the SRK/T formula (0.18D, p<0.001). The refractive prediction within ±0.50D ranged between 72.92% (Hoffer Q) and 100% (Barrett Universal II).


IOL power calculation for eyes with flat and steep corneas requires the use of specific formulas for accurate postoperative refraction. An adjustment equation for optimized K values with SRK/T formulas is proposed.

Financial Disclosure:


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