The Accuracy of Different Generation Intraocular Lens Power Formulas in Eyes with Axial Length Lower than 22 millimeter

2019 ◽  
Author(s):  
Aydın Yildiz ◽  
Sedat Arikan
Keyword(s):  
Intraocular Lens ◽  
Axial Length ◽  
Statistical Significance ◽  
Absolute Error ◽  
Accurate Estimation ◽  
Intraocular Lens Power ◽  
Significant Difference ◽  
Iol Calculation ◽  
Iol Power ◽  
Lens Power

Abstract Background:To investigate the accurate formulas for eyes with axial length (AL) lower than 22 millimeters among usually used six intraocular lens (IOL) calculation formulas. MethodsA total of 122 eyes with short ALs that is lower than 22 mm of 122 patients who underwent phacoemulsification surgery with the same type of IOL implantation were included in this retrospective study. The biometric values of the patients were obtained by using optical low coherence reflectometry (OLCR) for six formulas involving Hoffer Q, SRK-T, Haigis, Barett Universal II, Holladay 2 and Hill-RBF. All patients had a postoperative best corrected visual acuity level that is equal or higher than 20/40. While comparing the accuracy of these six IOL calculation formulas, the mean absolute error (MAE), and the median absolute error (MedAE) values were taken into account.ResultsThe MAE values for Hoffer Q, SRK-T, Haigis, Holladay 2, Hill-RBF and Barrett Universal II formulas were 0.390, 0.390, 0.324, 0.327, 0.331 and 0.208 respectively. Also the rank of MedAE values for the mentioned formulas was 0.245, 0.310, 0.310, 0.250, 0.255 and 0.190. The lowest MAE and MedAE value was found in Barrett Universal II formula, whereas the highest one was in the SRK/T formula with a statistical significance (p<0.001). After Bonferroni correction, there were no statistically significant difference between Barret Universal II formula and the other formulas except SRK/T (p>0.01). Three patients (2.5%) were in the ±0.75 D range, 15 patients (12.3%) were in the ±0.50 D, and the remaining 104 (85.2%) patients were in the ±0.25 D at the first month follow-up. ConclusionsAlthough Barrett Universal II appears to be the most accurate IOL calculation formula, third, fourth and other newer generation formulas have also a good predictive value for accurate estimation of IOL power in short eyes.

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

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.

scholarly journals Accuracy of Intraocular Lens Power Calculation Formulas for Highly Myopic Eyes

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
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.

scholarly journals Accuracy of Intraocular Lens Power Formulas Involving 148 Eyes with Long Axial Lengths: A Retrospective Chart-Review Study

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Chong Chen ◽  
Xian Xu ◽  
Yuyu Miao ◽  
Gaoxin Zheng ◽  
Yong Sun ◽  
...  
Keyword(s):  
Intraocular Lens ◽  
Axial Length ◽  
Retrospective Chart Review ◽  
Absolute Error ◽  
Intraocular Lenses ◽  
Chinese Patients ◽  
Power Calculation ◽  
Intraocular Lens Power Calculation ◽  
Intraocular Lens Power ◽  
Lens Power

Purpose. This study aims to compare the accuracy of intraocular lens power calculation formulas in eyes with long axial lengths from Chinese patients subjected to cataract surgery.Methods. A total of 148 eyes with an axial length of >26 mm from 148 patients who underwent phacoemulsification with intraocular lens implantation were included. The Haigis, Hoffer Q, Holladay 1, and SRK/T formulas were used to calculate the refractive power of the intraocular lenses and the postoperative estimated power.Results. Overall, the Haigis formula achieved the lowest level of median absolute error 1.025 D (P<0.01for Haigis versus each of the other formulas), followed by SRK/T formula (1.040 D). All formulas were least accurate when eyes were with axial length of >33 mm, and median absolute errors were significantly higher for those eyes than eyes with axial length = 26.01–30.00 mm. Absolute error was correlated with axial length for the SRK/T (r=0.212,P=0.010) and Hoffer Q (r=0.223,P=0.007) formulas. For axial lengths > 33 mm, eyes exhibited a postoperative hyperopic refractive error.Conclusions. The Haigis and SRK/T formulas may be more suitable for calculating intraocular lens power for eyes with axial lengths ranging from 26 to 33 mm. And for axial length over 33 mm, the Haigis formula could be more accurate.

scholarly journals Accuracy of intraocular lens power calculation using Scheimpflug tomography and OKULIX ray tracing software in corneal scarring

2019 ◽  
Author(s):  
Karim Mahmoud Nabil
Keyword(s):  
Visual Acuity ◽  
Ray Tracing ◽  
Intraocular Lens ◽  
Absolute Error ◽  
Power Calculation ◽  
Corneal Scarring ◽  
Iol Power Calculation ◽  
Intraocular Lens Power ◽  
Iol Power ◽  
Lens Power

Abstract Background: To evaluate the accuracy of intraocular lens power (IOL) calculation using Scheimpflug tomography and OKULIX ray tracing software in corneal scarring. Methods: This study was conducted on 40 consecutive eyes, 20 cases with corneal scarring and coexisting cataract, and 20 controls with clear cornea, which underwent uneventful phacoemulsification and IOL implantation following Scheimpflug tomography and OKULIX ray tracing software and third generation IOL power calculation formulas for IOL power calculation. Accuracy of IOL power calculation was evaluated by subtracting expected and achieved spherical refraction 3 months postoperatively and was recorded as mean absolute error (MAE). Distance uncorrected visual acuity (UCVA) for each eye was measured using Snellen chart preoperatively and 3 months postoperatively; visual acuity was scored and converted to the logarithm of the minimum angle of resolution (LogMar). Results: In cases of corneal scarring, 20 eyes (100 %) yielded a postoperative spherical refraction which differed less than 1 diopter (D) from predicted, in 16 eyes (80 %) the postoperative spherical refraction was within 0.50 D from expected. The MAE was 0.2 D in cases, which did not differ significantly compared to controls (MAE 0.1 D). In corneal scarring cases, distance UCVA showed significant improvement from 1.3 Log Mar (Snellen equivalent 20/400) preoperatively to 0.5 Log Mar (Snellen equivalent 20/60) 3 months postoperatively. Conclusion: Scheimpflug tomography combined with OKULIX ray tracing software for calculation of IOL power provides accurate results in cases of corneal scarring.

scholarly journals Comparison of four formulas for the intraocular lens power prediction

2019 ◽  
Author(s):  
Yanjun Hua ◽  
Wei Qiu ◽  
Qiang Wu
Keyword(s):  
Prospective Study ◽  
Intraocular Lens ◽  
Axial Length ◽  
Power Prediction ◽  
Ocular Biometry ◽  
Intraocular Lens Power ◽  
Iol Power ◽  
Lens Power ◽  
Better Than

Abstract Purpose To assess the accuracy of four formulas for intraocular lens (IOL) power prediction in cataractous eyes. METHODS In this prospective study, 51 eyes of 38 cataractous patients with an axial length (AL) between 24.0 and 26.0 mm were included. Preoperatively, Topolyzer, IOLMaster and A-scan were performed. At least 3 months after the surgery, subjective refraction was conducted. Haigis, SRK/T, Hoffer Q and Holladay 1 formulas based on ocular biometry from A-scan combining Topolyzer, IOLMaster combining Topolyzer and IOLMaster only were applied for IOL power prediction. RESULTS The four formulas based on biometry from IOLMaster combining Topolyzer and IOLMaster only performed better than those based on biometry from A-scan combining Topolyzer. Based on biometry from IOLMaster combining Topolyzer, Haigis formula had a mean NEs of -0.03 ± 0.71 D and a mean AEs of 0.53 ± 0.47 D, SRK/T formula had a mean NEs of 0.37 ± 0.72 D and a mean AEs of 0.63 ± 0.50 D, Hoffer Q formula had a mean NEs of 0.05 ± 0.62 D and a mean AEs of 0.43 ± 0.44 D, Holladay 1 formula had a mean NEs of 0.32 ± 0.63 D and a mean AEs of 0.54 ± 0.45 D. Based on biometry from IOLMaster only, Haigis formula had a mean NEs of 0.02 ± 0.54 D and a mean AEs of 0.41 ± 0.36 D, SRK/T formula had a mean NEs of 0.41 ± 0.54 D and a mean AEs of 0.52 ± 0.43 D, Hoffer Q formula had a mean NEs of 0.05 ± 0.58 D and a mean AEs of 0.36 ± 0.46 D, Holladay 1 formula had a mean NEs of 0.32 ± 0.45 D and a mean AEs of 0.43 ± 0.35 D. CONCLUSIONS Haigis and Hoffer Q formulas performed slightly better than SRK/T and Holladay 1 formulas. Therefore, for cataractous patients with moderate AL, all four formulas based the biometry from IOLMaster combining Topolyzer and IOLMaster only can be used for the prediction of IOL power, and the Haigis and Hoffer Q formulas are particularly recommended.

scholarly journals Comparison of Biometric Values and Intraocular Lens Power Calculations Obtained by Ultrasound and Optical Biometry

2016 ◽  
Vol 17 (4) ◽  
pp. 321-326
Author(s):  
Aleksandra Cvetkovic ◽  
Suncica Sreckovic ◽  
Marko Petrovic
Keyword(s):  
Intraocular Lens ◽  
Axial Length ◽  
Mean Values ◽  
Optical Biometry ◽  
Refractive Power ◽  
Number Of Patients ◽  
Significant Difference ◽  
Iol Power ◽  
The Mean ◽  
Lens Power

Abstract This study sought to compare the biometric values and intraocular lens (IOL) power obtained by standard ultrasound and optical biometry. We examined 29 eyes in preparation for cataract surgery. None of the patients had refractive surgery or corneal anomaly. In all patients, the horizontal and vertical refractive power of the cornea was determined using a keratometer (Bausch&Lomb). The axial length of the eye was determined via A-scan ultrasound (BVI-compact-V-plus) using Hollady’s formula. The IOL power and complete biometric measurements were obtained via an IOL Master-500-Zeiss using the Hollady-2 formula. All obtained values were compared and analysed using the statistical program SPSS 20. The average age of treated patients was 71.21±1.68 years. In 16 patients with dense cataracts (55.17%), it was not possible to determine the IOL power by optical biometry. Optical biometry obtained significantly increased axial length values of 24.04±0.29 mm compared with those obtained with ultrasound biometry (23.89±0.28 mm, p=0.003). The mean refractive cornea power values of the horizontal meridian measured using a keratometer (42.50±0.47 D) and an IOL Master (42.69±0.49 D) were not statistically different (p=0.187). The mean values of the refractive cornea power of the vertical meridian obtained using a keratometer (42.62±0.48D) and an IOL Master (43.36±0.51 D) exhibited a statistically significant difference (p=0.000). The keratometer obtained statistically significant lower mean values of corneal refractive power (42.73±0.32 D) compared with those obtained with optical biometry (43.22±0.35 D, p=0.000). Ultrasound biometry obtained significantly increased the mean values of IOL power (20.19±0.48D) compared with those obtained with optical biometry (19.71±0.48 D, p=0.018). The large number of patients who receive an operation for dense cataracts indicate the need for representation of both biometric methods in our clinical practice.

scholarly journals OPTIMAL SINGLE INTRAOCULAR LENS POWER (IOL) CALCULATION FOR ADULT POPULATION

1969 ◽  
Vol 4 (2) ◽  
pp. 497-502
Author(s):  
ASIF IQBAL ◽  
FAKHAR UL ISLAM ◽  
BILAL BASHIR ◽  
MOHAMMAD IDRIS ◽  
OMER KHAN ORAKZAI
Keyword(s):  
Visual Acuity ◽  
Cataract Surgery ◽  
Intraocular Lens ◽  
Axial Length ◽  
Adult Population ◽  
Small Incision Cataract Surgery ◽  
Minimum Power ◽  
Intraocular Lens Power ◽  
Iol Power ◽  
Lens Power

OBJECTIVES: To determine the single optimal intraocular lens power based on average biometricassessment for adult cataract surgery in free eye camps.MATERIALS AND METHODS: Prospective observational study of 4 years duration from 1stFebruary 2010 to 31st January 2014.SETTING: Community based Trust eye hospital in Tarakai village of District Swabi.METHODS: All adult patients, undergoing cataract surgery with intraocular lens (IOL) implantationwere included in the study after informed consent and fulfilling the inclusion and exclusion criteria. Allpatients were operated by manual small incision cataract surgery by the same surgeon (AI). Preoperative and Post- operative best spectacle corrected visual acuity (BSCVA) at two months follow upwas noted. Keratometric readings (K1 & K2), axial length and IOL power were calculated and dataanalyzed by using SPSS version 20 software database.RESULTS: Out of 1500 patients with cataract 668 (44.5%) were males and 832 (55.5%) were females.Right eye was involved in 826 (55.1%) patients whereas; left eye was involved in 674 (44.9%) patients.Mean K1 reading was 44.82± 1.80 D. Mean K2 reading was 44.94± 1.80 D. Mean axial length readingwas 23.11± 1.28 mm. 36.6 ifc(n=403) patients had axial length between 23-23.99 mm. Mean IOL powerin dioptres for males was 20.06± 2.53 D with minimum power of 2.00 D, maximum was 27 D and modewas 20.00 D. Mean IOL power in dioptres for females was 20.12 ± 3.43 D with minimum power of -2.00 D, maximum was 36.50 D and mode was 20.00 D. Mean IOL power was 20.10 ± 3.06 D. In 798patients (53.2 %) IOL used was in the range of 20.00 D to 22.00 D. Pre-operative best spectaclecorrected visual acuity was <6/60 in 58.4% (n=877) patients. Post operative best corrected visual acuity6/18 or better was present in 90.5% (n= 1357) patients at two months follow up.CONCLUSION: In community eye care centers located in far-flung areas with no facilities for properbiometric assessment of cataract patients, using an IOL power in the range of 20.00 D to 22.00 D wouldgive optimal visual results.KEY WORDS: Biometry, Keratometric readings, Axial Length, Intraocular lens.

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