UNASSIGNED: To compare the accuracy of modern intraocular lens (IOL) power calculation formulas with that of older formulas, such as SRK/T and Hoffer Q, in pediatric cataract surgery.
UNASSIGNED: This retrospective study included 100 eyes of 100 children who underwent routine cataract surgery with primary IOL implantation in a bag. This study used four IOLMaster 700 integrated formulas: SRK/T, Hoffer Q, Haigis, and Barrett Universal II (BUII). In addition, the following formulas were used: EVO 2.0, Hill RBF 3.0, Hoffer QST, Kane, and PEARL DGS, which are available online.
UNASSIGNED: There was a statistically significant difference between SRK/T and most other formulas, except for Hoffer Q, Hoffer QST, and BUII (p < 0.05). SRK/T yielded the lowest median absolute error (MedAE) of 0.63 D. This was followed by the BUII (0.66 D), Hoffer Q, and Hoffer QST (0.68 D). SRK/T also yielded the highest percentage of cases within ± 0.50 D (43% of the cases). For patients aged 2 to 5 years, SRK/T formula yielded statistically significantly better results than all other included formulas (p < 0.05) with MedAE = 0.44 D, 58.33% and 87.50% of the cases were within ± 0.50 D and ± 1.0 D of intended refraction, respectively.
UNASSIGNED: The SRK/T formula showed the best IOL power calculation results in pediatric cataract surgery, followed by BUII, Hoffer Q, and Hoffer QST. In children aged 2-5 years, the SRK/T formula outperformed all other formulas, followed by the BUII and Hoffer QST formulas. In children older than 5 years, there was no statistically significant difference between the different formulas (p > 0.05); Hoffer Q and SRK/T showed slightly better MedAE in this age group (5-10 years).

OBJECTIVE: This study evaluates the accuracy of modern intraocular lens (IOL) calculation formulas using axial length (AL) data obtained by ultrasound biometry (UBM) compared to the third-generation SRK/T calculator.
METHODS: The study included 230 patients (267 eyes) with severe lens opacities that prevented optical biometry, who underwent phacoemulsification (PE) with IOL implantation. IOL power calculation according to the SRK/T formula was based on AL and anterior chamber depth obtained by UBM (Tomey Biometer Al-100) and keratometry on the Topcon KR 8800 autorefractometer. To adapt AL for new generation calculators - Barrett Universal II (BUII), Hill RBF ver. 3.0 (RBF), Kane and Ladas Super Formula (LSF) - the retinal thickness (0.20 mm) was added to the axial length determined by UBM, and then the optical power of the artificial lens was calculated. The mean error and its modulus value were used as criteria for the accuracy of IOL calculation.
RESULTS: A significant difference (p=0.008) in the mean IOL calculation error was found between the formulas. Pairwise analysis revealed differences between SRK/T (-0.32±0.58 D) and other formulas - BUII (-0.16±0.52 D; p=0.014), RBF (-0.17±0.51 D; p=0.024), Kane (-0.17±0.52 D; p=0.029), but not with the LSF calculator (-0.19±0.53 D; p=0.071). No significant differences between the formulas were found in terms of mean error modulus (p=0.238). New generation calculators showed a more frequent success in hitting target refraction (within ±1.00 D in more than 95% of cases) than the SRK/T formula (86%).
CONCLUSIONS: The proposed method of adding 0.20 mm to the AL determined by UBM allows using this parameter in modern IOL calculation formulas and improving the refractive results of PE, especially in eyes with non-standard anterior segment structure.
UNASSIGNED: Оценка точности современных формул расчета интраокулярных линз (ИОЛ) с использованием данных о длине переднезадней оси (ПЗО), полученных при ультразвуковой биометрии (УЗБ), по сравнению с калькулятором третьего поколения SRK/T.
UNASSIGNED: В исследование включено 230 пациентов (267 глаз) с выраженными помутнениями хрусталика, препятствовавшими выполнению оптической биометрии, которым была проведена факоэмульсификация (ФЭ) с имплантацией ИОЛ. Калькуляция оптической силы ИОЛ по формуле SRK/T основывалась на длине ПЗО и глубине передней камеры, полученных с помощью контактной УЗБ (Tomey Biometer Al-100) и кератометрии на авторефрактокератометре Topcon KR 8800. В целях адаптации ПЗО для калькуляторов нового поколения — Barrett Universal II (BUII), Hill RBF ver. 3.0 (RBF), Kane и Ladas Super Formula (LSF) — к определяемой с помощью УЗБ аксиальной длине добавлялась толщина сетчатки (0,20 мм), а затем вычислялась оптическая сила искусственного хрусталика. В качестве критериев точности расчета ИОЛ использовались средняя ошибка и модуль ее значения.
UNASSIGNED: Обнаружена значимая разница (p=0,008) в средней ошибке расчета ИОЛ между формулами. Попарный анализ выявил различия между SRK/T (–0,32±0,58 дптр) и другими формулами — BUII (–0,16±0,52 дптр; p=0,014), RBF (–0,17±0,51 дптр; p=0,024), Kane (–0,17±0,52 дптр; p=0,029), но не с калькулятором LSF (–0,19±0,53 дптр; p=0,071). Значимых различий между формулами по параметру модуля средней ошибки найдено не было (p=0,238). Калькуляторы новых поколений показали более частое попадание в рефракцию цели (в пределах ±1,00 дптр более чем в 95% случаев), чем формула SRK/T (86%).
UNASSIGNED: Предложенный метод добавления 0,20 мм к определяемой с помощью УЗБ длине ПЗО позволяет использовать данный параметр в современных формулах расчета ИОЛ и улучшать рефракционные результаты ФЭ, особенно в глазах с нестандартным строением переднего отрезка.

OBJECTIVE: The study assesses the influence of gender on the accuracy of intraocular lens (IOL) power calculation by formulas SRK/T, Barrett Universal II (BUII), Ladas super formula (LSF), Hill RBF (RBF) and Kane.
METHODS: The study enrolled 214 patients (106 men and 108 women) who underwent cataract phacoemulsification (PE). Optical biometry was performed on IOL-Master 500. IOL power calculation was performed either adjusting for gender (formulas SRK/T, BUII, LSF) or without such adjustment (formulas RBF, Kane). Calculation error (CE) was assessed one month after PE by comparing the achieved (autorefractometer Topcon-8800) and target spherical equivalent of refraction.
RESULTS: Significant differences were found in mean IOL CE with gender-unspecific formulas (SRK/T, BUII, LSF) and no differences in gender-specific calculators (RBF, Kane). The Kane formula demonstrated the lowest CE between men and women (-0.01±0.43 versus -0.09±0.41 D; p=0.158), while the SRK/T formula had the highest CE (0.02±0.46 versus -0.21±0.44 D, respectively; p<0.001). Presence of a significant correlation between CE and gender was found for all formulas except Kane (R2=0.005, p=0.158).
CONCLUSIONS: Patient\'s gender has a significant impact on IOL calculation accuracy. Using gender-responsive formulas could help achieve better refractive results with PE. The present study showed Kane formula to have the least CE dependence from gender. However, the CE difference (less than 0.25 D) was lower than the value of division (0.5D) in modern IOL models.
UNASSIGNED: Оценить влияние пола пациентов на точность расчета интраокулярных линз (ИОЛ) по формулам SRK/T, Barrett Universal II (BUII), Ladas Super Formula (LSF), Hill RBF (RBF) и Kane.
UNASSIGNED: В исследование включено 214 пациентов (106 мужчин и 108 женщин), которым была выполнена факоэмульсификация (ФЭ). Биометрия осуществлялась на аппарате IOL-Master 500. Оптическая сила ИОЛ определялась как без учета (формулы SRK/T, BUII, LSF), так и с поправками на пол оперируемых (калькуляторы RBF, Kane). Ошибка расчета (ОР) ИОЛ оценивалась спустя 1 мес после ФЭ путем сравнения сфероэквивалентов достигнутой клинической рефракции (авторефрактометр Topcon-8800) и расчетной рефракции.
UNASSIGNED: Выявлены значимая разница в ОР ИОЛ для мужчин и женщин, сопровождающая применение формул, не учитывающих пол (SRK/T, BUII, LSF), и ее отсутствие при использовании калькуляторов RBF и Kane. Формула Kane продемонстрировала минимальную разницу ОР между мужчинами и женщинами (–0,01±0,43 против –0,09±0,41 дптр; p=0,158), а SRK/T — максимальную (0,02±0,46 против –0,21±0,44 дптр соответственно; p<0,001). Установлено наличие значимой связи ОР ИОЛ с полом для всех формул, кроме Kane (R2=0,005, p=0,158).
UNASSIGNED: Пол пациента значимо влияет на ОР ИОЛ, что обусловливает целесообразность использования формул, учитывающих эту переменную, в первую очередь калькулятора Kane. Однако стоит отметить, что данное влияние невелико (менее 0,25 дптр) и не превышает шаг современных моделей ИОЛ (0,5 дптр).

To evaluate a method using measured values of total corneal refractive power (TCRP) for a manufacturer\'s online calculator by comparing it with the Barrett toric calculator (BTC) and Kane toric calculator (KTC) combined with simulated keratometry values (SimK).
This was a retrospective case series. Patient records were reviewed to identify the patients who had biometry with the IOL Master 700 and Pentacam recorded before toric IOL implantation and refractive follow-up data after implantation. The predicted error in residual astigmatism was calculated by vector analysis according to the calculation methods and the measurements used.
A total of 70 eyes of 56 patients were included. The mean absolute astigmatism prediction errors were 0.6 ± 0.32, 0.59 ± 0.35, and 0.61 ± 0.35 D for the ATCTCRP, BTCSimK, and KTCSimK calculators, respectively (P = 0.934), and the centroid of the prediction errors were 0.3 D @ 178°, 0.11 D @ 102°, and 0.09 D @ 147°, respectively (P = 0.23). In the with-the-rule subgroup, the centroid of the prediction error was 0.34 D @ 176° for ATCTCRP and was the highest among the three calculation methods (P = 0.046).
The ATCTCRP, BTCSimK, and KTCSimK calculators had similar performance with regards to their astigmatism prediction accuracy. The ATCTCRP calculator combined with 4.0-mm apex/ring readings of TCRP was slightly intended to result in against-the-rule residual astigmatism.

OBJECTIVE: The purpose of this study was to report the clinical and refractive outcomes of eyes with long axial length (AL) and high myopia that underwent cataract surgery and compare the performance of intraocular lens (IOL) calculation formulae on these eyes.
METHODS: This retrospective cohort included 183 eyes that underwent cataract surgery from January 2010 to December 2018. Demographics, AL, postoperative best-visual acuities, IOL power data, and postoperative complications were recorded. Refractive outcomes were analyzed and absolute predicted errors were compared between five IOL calculation formulas.
RESULTS: The mean age included in the study was 65.4 ± 9.39 years with a mean AL of 26.76 ± 1.75 mm. Postoperatively, the mean sphere, cylinder, and manifest refraction spherical equivalent were 0.22 D ± 0.54, -0.78 D ± 0.50, and - 0.16 D ± 0.50, respectively. The average IOL power implanted was 11.12 D ± 4.59 D. No intraoperative complications were encountered, but there was one incidence of retinal tear with detachment reported postoperatively (0.55%). The Kane formula had the lowest mean absolute predicted error (MAE). A significant positive correlation between increasing AL and MAE was seen in the Sanders, Retzlaff and Kraft-Theoretical (SRK-T) and Ladas formulae but not statistically significant when the Kane, Barrett Universal II, and the Emmetropia Verifying Optical (EVO) formulae were used.
CONCLUSIONS: Cataract surgery in eyes with long ALs and high myopia is safe with a low incidence of intraoperative and postoperative complications. The Kane, Barrett, and EVO formulae were equally accurate in calculating the IOL power and achieved the least amount of residual error postoperatively.

The purpose of this study was to compare the accuracy of several intraocular (IOL) lens power calculation formulas in long eyes. This was a single-site retrospective consecutive case series that reviewed patients with axial lengths (AL) > 28.0 mm who underwent phacoemulsification. The Wang−Koch (WK) adjustment and Cooke-modified axial length (CMAL) adjustment were applied to Holladay 1 and SRK/T. The median absolute error (MedAE) and the percentage of eyes with prediction errors ±0.25 diopters (D), ±0.50 D, ±0.75 D, and ±1.00 D were used to analyze the formula’s accuracy. This study comprised a total of 35 eyes from 25 patients. The Kane formula had the lowest MedAE of all the formulas, but all were comparable except Holladay 1, which had a significantly lower prediction accuracy with either AL adjustment. The SRK/T formula with the CMAL adjustment had the highest accuracy in predicting the formula outcome within ±0.50 D. The newer formulas (BU-II, EVO, Hill-RBF version 3.0, and Kane) were all equally predictable in long eyes. The SRK/T formula with the CMAL adjustment was comparable to these newer formulas with better outcomes than the WK adjustment. The Holladay 1 with either AL adjustment had the lowest predictive accuracy.

UNASSIGNED: To investigate the accuracy of Okulix ray-tracing software in calculating intraocular lens (IOL) power in the long cataractous eyes and comparing the results with those obtained from Kane, Holladay 1 with optimized constant, SRK/T with optimized constant, Haigis with optimized constant, and Barret Universal 2 formulas.
UNASSIGNED: The present study evaluates the refractive results of cataract surgery in 85 eyes with axial length > 25 mm and no history of ocular surgery and corneal pathology. IOL power calculation was performed using the Okulix software. The performances of Okulix software in comparison with the five other formulas were evaluated by predicted error, mean absolute error, and mean numerical error 6 months after surgery.
UNASSIGNED: The mean calculated IOL power by the Okulix software was +13.48 ± 4.19 diopter (D). The mean of the 6-month postoperative sphere and spherical equivalent were +0.18 ± 0.63 and -0.34 ± 0.78 D, respectively. Also, the 6-month spherical equivalent in 56.6% and 80% of eyes were within ±0.05 and ±1.00 D, respectively. The predicted error (P < 0.001) and the mean numerical error (P < 0.001) were different between the six studied methods; however, we were not able to find any significant differences in the mean absolute error among six studied methods (P: 0.211).
UNASSIGNED: The present study showed acceptable performance of the Okulix software in IOL power calculation in long eyes in comparison with the other five methods based on the postoperative refractive error, calculated mean absolute error, and mean numerical error.

OBJECTIVE: To evaluate the accuracy of the Kane formula for intraocular lens (IOL) power calculation in comparison with existing formulas by incorporating optional variables into calculation.
METHODS: This retrospective review consisted of 78 eyes of patients who had undergone uneventful phacoemulsification with intraocular implantation at Severance Hospital in Seoul, Korea between February 2020 and January 2021. The Kane formula was compared with six of the existing IOL formulas (SRK/T, Hoffer-Q, Haigis, Holladay1, Holladay2, Barrett Universal II) based on the mean absolute error (MAE), median absolute error (MedAE), and the percentages of eyes within prediction errors of ±0.25D, ±0.50D, and ±1.00D.
RESULTS: The Barrett Universal II formula demonstrated the lowest MAEs (0.26±0.17D), MedAEs (0.28D), and percentage of eyes within prediction errors of ±0.25D, ± 0.50D, and ±1.00D, although there was no statistically significant difference between Barrett Universal II-SRK/T (p=0.06), and Barrett Universal II-Kane formula (p<0.51). Following the Barrett Universal II formula, the Kane formula demonstrated the second most accurate formula with MAEs (0.30±0.19D) and MedAEs (0.28D). However, no statistical difference was shown between Kane-Barrett Universal II (p=0.51) and Kane-SRK/T (p=0.14).
CONCLUSIONS: Although slightly better refractory outcome was noted in the Barrett Universal II formula, the performance of the Kane formula in refractive prediction was comparable in IOL power calculation, marking its superiority over many conventional IOL formulas, such as HofferQ, Haigis, Holladay1, and Holladay2.