Accuracy of intraocular lens power calculation formulas in a steep cornea: A case report

There is no enough knowledge about the accuracy of intraocular lens (IOL) power calculation formulas in steep corneas. This study may be the first one that compares the accuracy of the SRK II formula with Holladay1, Hoffer Q and Haigis formulas in steep corneas. We reported a case of a 60-year-old female, with a cataract in the left eye and with a steep cornea. We used the modern formulas; Holladay1, Hoffer Q and Haigis. The result (+7.0D) was unexpected compared to the manifest refraction and to the IOL power calculated in the right eye using the same formulas which was (+17.0D). We implanted (+12.0D) Sensar 1-piece IOL depending on our clinical experience. The post-operative refraction was (+0.00/-1.75axis106). Postoperative, we used the patient data to find the best formula in this case. We found that the SRK II (A118) result was (+11.5D) and thus this formula was the most accurate in this case. Keywords: SRK II; Holladay1; Hoffer Q; Haigis

Download Full-text

Intraocular Lens Power Calculation – Still Searching for the Holy Grail

European Ophthalmic Review ◽

10.17925/eor.2015.09.01.13 ◽

2015 ◽

Vol 09 (01) ◽

pp. 13

Author(s):

Nino Hirnschall ◽

Oliver Findl ◽

◽

Keyword(s):

Intraocular Lens ◽

Power Calculation ◽

Refractive Outcome ◽

Intraocular Lens Power Calculation ◽

Iol Power Calculation ◽

Lens Position ◽

Intraocular Lens Power ◽

Iol Power ◽

Lens Power ◽

Lens Power Calculation

Since the introduction of optical biometry and modern intraocular lens (IOL) power calculation formulae, the refractive outcome after cataract surgery improved significantly. This is necessary, as patient demand for spectacle independence is increasing. However, especially when it comes to short and long eyes, all formulae have their difficulties in predicting the effective lens position – and, therefore, the post-operative refractive outcome. This review summarises the development of IOL power calculation formulae, explains their basics and presents some alternative calculation methods.

Download Full-text

Accuracy of Intraocular Lens Power Calculation Formulas for Highly Myopic Eyes

Journal of Ophthalmology ◽

10.1155/2016/1917268 ◽

2016 ◽

Vol 2016 ◽

pp. 1-7 ◽

Cited By ~ 9

Author(s):

Yichi Zhang ◽

Xiao Ying Liang ◽

Shu Liu ◽

Jacky W. Y. Lee ◽

Srinivasan Bhaskar ◽

...

Keyword(s):

Intraocular Lens ◽

Absolute Error ◽

Power Calculation ◽

Prediction Errors ◽

Intraocular Lens Power Calculation ◽

Iol Power Calculation ◽

Predictive Error ◽

Intraocular Lens Power ◽

Iol Power ◽

Lens Power

Purpose.To evaluate and compare the accuracy of different intraocular lens (IOL) power calculation formulas for eyes with an axial length (AL) greater than 26.00 mm.Methods.This study reviewed 407 eyes of 219 patients with AL longer than 26.0 mm. The refractive prediction errors of IOL power calculation formulas (SRK/T, Haigis, Holladay, Hoffer Q, and Barrett Universal II) using User Group for Laser Interference Biometry (ULIB) constants were evaluated and compared.Results.One hundred seventy-one eyes were enrolled. The Barrett Universal II formula had the lowest mean absolute error (MAE) and SRK/T and Haigis had similar MAE, and the statistical highest MAE were seen with the Holladay and Hoffer Q formulas. The interquartile range of the Barrett Universal II formula was also the lowest among all the formulas. The Barrett Universal II formulas yielded the highest percentage of eyes within ±1.0 D and ±0.5 D of the target refraction in this study (97.24% and 79.56%, resp.).Conclusions.Barrett Universal II formula produced the lowest predictive error and the least variable predictive error compared with the SRK/T, Haigis, Holladay, and Hoffer Q formulas. For high myopic eyes, the Barrett Universal II formula may be a more suitable choice.

Download Full-text

3 Postrefractive Intraocular Lens Power Calculation: Choosing the Right Nomogram

Optimizing Suboptimal Results Following Cataract Surgery ◽

10.1055/b-0038-166347 ◽

2019 ◽

Keyword(s):

Intraocular Lens ◽

Power Calculation ◽

Intraocular Lens Power Calculation ◽

Intraocular Lens Power ◽

Lens Power ◽

The Right ◽

Lens Power Calculation

Download Full-text

Intraocular lens power calculation formula accuracy: Comparison of 12 formulas for a trifocal hydrophilic intraocular lens

European Journal of Ophthalmology ◽

10.1177/1120672120980690 ◽

2020 ◽

pp. 112067212098069

Author(s):

Carlos Rocha-de-Lossada ◽

Elvira Colmenero-Reina ◽

David Flikier ◽

Francisco-Javier Castro-Alonso ◽

Alvaro Rodriguez-Raton ◽

...

Keyword(s):

Intraocular Lens ◽

Axial Length ◽

Absolute Error ◽

Power Calculation ◽

Intraocular Lens Power Calculation ◽

Accuracy Comparison ◽

Intraocular Lens Power ◽

Iol Power ◽

Lens Power ◽

Lens Power Calculation

Purpose: To evaluate the accuracy of 12 intraocular lens (IOL) power formulas; Barrett Universal II, Emmetropia Verifying Optical (EVO), Haigis, Hill-Radial Basis Function (RBF), Hoffer Q, Holladay I, Kane, Ladas Super Formula, Olsen Lenstar, Panacea, Pearl-DGS, Sanders-Retzlaff-Kraff/theoretical (SRK/T). In addition, an analysis of the efficacy as a function of the axial length was performed. Methods: About 171 from 93 patients: 68 male eyes and 103 female eyes. Twelve IOL power formula calculations were studied with one IOL platform (trifocal hydrophilic IOL, FineVision Micro F), one biometer (Lenstar LS 900), one topographer (CSO Sirius Topographer), one surgeon, and one optometrist. Optimization were determined to be zeroed mean refractive prediction error. Mean error (ME), mean absolute error (MAE), median absolute error (MedAE) and refractive accuracy within ±1.00 D was calculated. Axial length was split in short and medium eyes. Results: One hundred and seventy eyes were included. Formulas were ranked by percentage within ±0.50 diopters and MAE (D). Among all eyes, Olsen 86.55% (0.273 D) and Barrett Universal II 86.55% (0.285D). For short eyes (<22.5 mm), Olsen 90.70% (0.273 D) and Kane 90.70% (0.225 D). For medium eyes, Barrett 89.34% (0.237 D) and Pearl 86.89% (0.263 D). Conclusion: Olsen and Barrett formula obtained excellent accuracy for overall eyes. Kane and Olsen formula obtained the best results in short eyes. For medium axial length Barrett formula achieved the best accuracy results.

Download Full-text