Posters
Comparison of IOL power calculation methods and measurement zone for cataract surgery undergone previous penetrating keratoplasty
Poster Details
First Author: D.Tomida JAPAN
Co Author(s): M. Suzuki Y. Yaguchi T. Yamaguchi S. Den Y. Satake J. Shimazaki
Abstract Details
Purpose:
To compare the accuracy of measurement zone of intraocular lens (IOL) power calculations used for cataract surgery undergone previous penetrating keratoplasty (PKP).
Setting:
All patients underwent an examination for cataract surgery and were performed cataract surgery at Tokyo Dental College Ichikawa General Hospital, Chiba, Japan.
Methods:
We evaluated the medical records of 15 eyes of 14 patients (mean age, 67.7�Â�±7.9 years; range 48�â��79 years) who underwent cataract surgery after PKP at our clinic. The prediction error, defined as the difference between the estimated postoperative spherical equivalent and the postoperative manifest refraction at the spectacle plane, was calculated using three formulas: SRK/T and Haigis with the difference measurement zone: the 3 or 6 mm diameter of keratometric, real and auto-kerato K value. We compared the median values of the arithmetic and absolute prediction errors among the formulas and measurement zone.
Results:
The minimum median refractive errors after cataract surgery in the three formulas and measurement zone were SRK/T measured on the 3mm diameter of cornea -0.14�Â�±2.93 D (diopter) (range -4.33 to 4.79). With regard to the median absolute refractive errors, SRK/T was tended to have less precise than Haigis (e.g. keratometric of 3mm 2.55�Â�±1.44, 3.16�Â�±1.96, p=0.11 real of 3mm 2.74�Â�±1.47, 3.45�Â�±1.74, p=0.06). In terms of the measurement zone, SRK/T showed less precision as compared with at 3mm than 6mm diameter with real (2.74�Â�±1.47, 5.84�Â�±2.43, p<0.05) and keratmetric (2.55�Â�±1.44, 6.08�Â�±3.14, p<0.05).
Conclusions:
To calculate the IOL powers in eyes that underwent PKP, SRK/T showed less precision then other formulas and the measurement diameter of 3mm is less precise than 6mm.
Financial Disclosure:
NONE
