Using equivalent keratometric readings in calculating the optical power of a multifocal intraocular lens

Abstract

BACKGROUND: Modern keratotopography allows calculating Equivalent Keratometer Readings (EKR), which take additionally into account in keratometry the radius of curvature of corneal posterior surface, and this could lead to more accurate calculation of the spherical equivalent (SE) of the intraocular lens.

AIM: The aim of this study is to determine the accuracy of calculating the SE of multifocal intraocular lens according to EKR data, depending on the formula used and the corneal zone.

MATERIALS AND METHOD: The study included 78 patients who underwent femtolaser-assisted phacoemulsification, multifocal intraocular lens implantation and achievement of the target refraction at different distances. Retrospective calculation of the optical power of the intraocular lens was performed using biometric data from OA-2000 and EKR (zones from 0.5 to 5 mm in increments of 0.5 mm) using 10 formulas (SRK/T, Holladay 1, Holladay 2, Haigis, Hoffer Q, Barrett 2 Universal, Olsen, Kane, EVO, Hill RBF). For each combination of keratometry zone/formula were calculated: mean error of predicted refraction (ME), its difference from zero, and after intraocular lens constant optimization — mean (MAE) and median (MedAE) absolute errors, standard deviation (SD).

RESULTS: Up to the 2.5 mm zone, ME is shifted towards hypermetropia, and from the 3 mm zone, ME begins to shift towards myopia according to all formulas. Minimal MAE, MedAE and SD values were detected in peripheral corneal zones (3–5 mm) for most formulas. The best indicators were demonstrated by the formula Haigis in zones 3.5–5 mm.

CONCLUSIONS: The most accurate calculation of the SE of a multifocal intraocular lens using EKR is possible when using the Haigis formula in 3.5–5 mm zones.

Keywords

equivalent keratometric indicators / keratotopography / corneal zone / calculation formulas / multifocal intraocular lenses / IOL

References

[1] Boiko EV, Vinnitskiy DA. Rehabilitation of patients after implantation of bifocal and trifocal intraocular lens. Fyodorov Journal of Ophthalmic Surgery. 2018;(2):67–74. EDN: XSNEBV doi: 10.25276/0235-4160-2018-2-67-74

[2] Бойко Э.В., Винницкий Д.А. Сравнение зрительной реабилитации с применением трифокальных и бифокальных интраокулярных линз (обзор литературы) // Офтальмохирургия. 2018. № 2. С. 67–74. EDN: XSNEBV doi: 10.25276/0235-4160-2018-2-67-74

[3] Boiko EV, Vinnitskiy DA. Rehabilitation of patients after implantation of bifocal and trifocal intraocular lens. Fyodorov Journal of Ophthalmic Surgery. 2018;(2):67–74. EDN: XSNEBV doi: 10.25276/0235-4160-2018-2-67-74

[4] Malyugin BE, Sobolev NP, Fomina OV. Visual assessment performance after implantation of a new trifocal intraocular lens. Fyodorov Journal of Ophthalmic Surgery. 2018;(4):6–14. EDN: ZXOZBV doi: 10.25276/0235-4160-2017-4-6-14

[5] Малюгин Б.Э., Соболев Н.П., Фомина О.В. Анализ функциональных результатов имплантации новой модели трифокальной интраокулярной линзы // Офтальмохирургия. 2018. № 4. С. 6–14. EDN: ZXOZBV doi: 10.25276/0235-4160-2017-4-6-14

[6] Malyugin BE, Sobolev NP, Fomina OV. Visual assessment performance after implantation of a new trifocal intraocular lens. Fyodorov Journal of Ophthalmic Surgery. 2018;(4):6–14. EDN: ZXOZBV doi: 10.25276/0235-4160-2017-4-6-14

[7] Kulikov AN, Kotova NA, Kokareva EV. K Toward the calculation of IOL optical power using “IOLmaster” and several keratotopography methods. Modern Technologies in Ophthalmology. 2016;(3):188–192. (In Russ.) EDN: WTIUHD

[8] Куликов А.Н., Котова Н.А., Кокарева Е.В. К вопросу расчёта оптической силы ИОЛ с помощью «IOLmaster» и нескольких методов кератотопографии // Современные технологии в офтальмологии. 2016. № 3. С. 188–192. EDN: WTIUHD

[9] Kulikov AN, Kotova NA, Kokareva EV. K Toward the calculation of IOL optical power using “IOLmaster” and several keratotopography methods. Modern Technologies in Ophthalmology. 2016;(3):188–192. (In Russ.) EDN: WTIUHD

[10] Trubilin VN, Il’inskaya IA. Corneal refractive power measurement using different methods. Kataraktal’naya i refrakcionnaya hirurgiya. 2014;14(2):4–9. (In Russ.) EDN: SFOVER

[11] Трубилин В.Н., Ильинская И.А. Определение оптической силы роговицы с помощью различных методов исследования. Обзор литературы // Катарактальная и рефракционная хирургия. 2014. Т. 14, № 2. С. 4–9. EDN: SFOVER

[12] Trubilin VN, Il’inskaya IA. Corneal refractive power measurement using different methods. Kataraktal’naya i refrakcionnaya hirurgiya. 2014;14(2):4–9. (In Russ.) EDN: SFOVER

[13] Karunaratne N. Comparison of the Pentacam equivalent keratometry reading and IOL Master keratometry measurement in intraocular lens power calculations. Clin Exp Ophthalmol. 2013;41(9): 825–834. doi: 10.1111/ceo.12124

[14] Karunaratne N. Comparison of the Pentacam equivalent keratometry reading and IOL Master keratometry measurement in intraocular lens power calculations // Clin Exp Ophthalmol. 2013. Vol. 41, N 9. P. 825–834. doi: 10.1111/ceo.12124

[15] Karunaratne N. Comparison of the Pentacam equivalent keratometry reading and IOL Master keratometry measurement in intraocular lens power calculations. Clin Exp Ophthalmol. 2013;41(9): 825–834. doi: 10.1111/ceo.12124

[16] Savini G, Hoffer KJ, Schiano et al. Simulated keratometry versus total corneal power by ray tracing. Cornea. 2017;36(11):1368–1372. doi: 10.1097/ico.0000000000001343

[17] Savini G., Hoffer K.J., Schiano Lomoriello D., Ducoli P. Simulated keratometry versus total corneal power by ray tracing // Cornea. 2017. Vol. 36, N 11. P. 1368–1372. doi: 10.1097/ico.0000000000001343

[18] Savini G, Hoffer KJ, Schiano et al. Simulated keratometry versus total corneal power by ray tracing. Cornea. 2017;36(11):1368–1372. doi: 10.1097/ico.0000000000001343

[19] Kiseleva TN, Oganesyan OG, Romanova LI, et al. Optical biometry of the eye: the principle and the diagnostic potential of the method. Russian Pediatric Ophthalmology. 2017;12(1):35–42. EDN: YTFEEX doi: 10.18821/1993-1859-2017-12-1-35-42

[20] Киселева Т.Н., Оганесян О.Г., Романова Л.И., и др. Оптическая биометрия глаза: принцип и диагностические возможности метода // Российская педиатрическая офтальмология. 2017. Т. 12, № 1. С. 35–42. EDN: YTFEEX doi: 10.18821/1993-1859-2017-12-1-35-42

[21] Kiseleva TN, Oganesyan OG, Romanova LI, et al. Optical biometry of the eye: the principle and the diagnostic potential of the method. Russian Pediatric Ophthalmology. 2017;12(1):35–42. EDN: YTFEEX doi: 10.18821/1993-1859-2017-12-1-35-42

[22] Kulikov AN, Kokareva EV, Kotova NA. Comparison of the results of the eye biometrics using different instruments. Pacific Medical Journal. 2017;(2):53–54. EDN: YPDDNL doi: 10.17238/PmJ1609-1175.2017.2.53-55

[23] Куликов А.Н., Кокарева Е.В., Котова Н.А. Сравнение результатов биометрии глаза при использовании различных приборов // Тихоокеанский медицинский журнал. 2017. № 2. С. 53–54. EDN: YPDDNL doi: 10.17238/PmJ1609-1175.2017.2.53-55

[24] Kulikov AN, Kokareva EV, Kotova NA. Comparison of the results of the eye biometrics using different instruments. Pacific Medical Journal. 2017;(2):53–54. EDN: YPDDNL doi: 10.17238/PmJ1609-1175.2017.2.53-55

[25] Mukhija R, Gupta N. Advances in anterior segment examination. Community Eye Health. 2019; 32(107):S5–S6.

[26] Mukhija R., Gupta N. Advances in anterior segment examination // Community Eye Health. 2019. Vol. 32, N 107. P. S5–S6.

[27] Mukhija R, Gupta N. Advances in anterior segment examination. Community Eye Health. 2019; 32(107):S5–S6.

[28] Kanclerz P, Khoramnia R, Wang X. Current developments in corneal topography and tomography. Diagnostics (Basel). 2021;11(8):1466. doi: 10.3390/diagnostics11081466

[29] Kanclerz P., Khoramnia R., Wang X. Current developments in corneal topography and tomography // Diagnostics (Basel). 2021. Vol. 11, N 8. P. 1466. doi: 10.3390/diagnostics11081466

[30] Kanclerz P, Khoramnia R, Wang X. Current developments in corneal topography and tomography. Diagnostics (Basel). 2021;11(8):1466. doi: 10.3390/diagnostics11081466

[31] Fan R, Chan TC, Prakash G, Jhanji V. Applications of corneal topography and tomography: a review. Clin Exp Ophthalmol. 2018;46(2):133–146. doi: 10.1111/ceo.13136

[32] Fan R., Chan T.C., Prakash G., Jhanji V. Applications of corneal topography and tomography: a review // Clin Exp Ophthalmol. 2018. Vol. 46, N 2. P. 133–146. doi: 10.1111/ceo.13136

[33] Fan R, Chan TC, Prakash G, Jhanji V. Applications of corneal topography and tomography: a review. Clin Exp Ophthalmol. 2018;46(2):133–146. doi: 10.1111/ceo.13136

[34] Saglik A, Celik H, Aksoy M. An analysis of Scheimpflug Holladay-equivalent keratometry readings following corneal collagen cross-linking. Beyoglu Eye J. 2019;4(2):62–68. doi: 10.14744/bej.2019.35220

[35] Saglik A., Celik H., Aksoy M. An analysis of Scheimpflug Holladay-equivalent keratometry readings following corneal collagen cross-linking // Beyoglu Eye J. 2019. Vol. 4, N 2. P. 62–68. doi: 10.14744/bej.2019.35220

[36] Saglik A, Celik H, Aksoy M. An analysis of Scheimpflug Holladay-equivalent keratometry readings following corneal collagen cross-linking. Beyoglu Eye J. 2019;4(2):62–68. doi: 10.14744/bej.2019.35220

[37] Shammas HJ, Hoffer KJ, Shammas MC. Scheimpflug photography keratometry readings for routine intraocular lens power calculation. J Cataract Refract Surg. 2009;35(2):330–334. doi: 10.1016/j.jcrs.2008.10.041

[38] Shammas H.J., Hoffer K.J., Shammas M.C. Scheimpflug photography keratometry readings for routine intraocular lens power calculation // J Cataract Refract Surg. 2009. Vol. 35, N 2. P. 330–334. doi: 10.1016/j.jcrs.2008.10.041

[39] Shammas HJ, Hoffer KJ, Shammas MC. Scheimpflug photography keratometry readings for routine intraocular lens power calculation. J Cataract Refract Surg. 2009;35(2):330–334. doi: 10.1016/j.jcrs.2008.10.041

[40] Wang Q, Savini G, Hoffer KJ, et al. A comprehensive assessment of the precision and agreement of anterior corneal power measurements obtained using 8 different devices. PLoS One. 2012;7(9): e45607. doi: 10.1371/journal.pone.0045607

[41] Wang Q., Savini G., Hoffer K.J., et al. A comprehensive assessment of the precision and agreement of anterior corneal power measurements obtained using 8 different devices // PLoS One. 2012. Vol. 7, N 9. P. e45607. doi: 10.1371/journal.pone.0045607

[42] Wang Q, Savini G, Hoffer KJ, et al. A comprehensive assessment of the precision and agreement of anterior corneal power measurements obtained using 8 different devices. PLoS One. 2012;7(9): e45607. doi: 10.1371/journal.pone.0045607

[43] Savini G, Barboni P, Carbonelli M, Hoffer KJ. Comparison of methods to measure corneal power for intraocular lens power calculation using a rotating Scheimpflug camera. J Cataract Refract Surg. 2013;39(4):598–604. doi: 10.1016/j.jcrs.2012.11.022

[44] Savini G., Barboni P., Carbonelli M., Hoffer K.J. Comparison of methods to measure corneal power for intraocular lens power calculation using a rotating Scheimpflug camera // J Cataract Refract Surg. 2013. Vol. 39, N 4. P. 598–604. doi: 10.1016/j.jcrs.2012.11.022

[45] Savini G, Barboni P, Carbonelli M, Hoffer KJ. Comparison of methods to measure corneal power for intraocular lens power calculation using a rotating Scheimpflug camera. J Cataract Refract Surg. 2013;39(4):598–604. doi: 10.1016/j.jcrs.2012.11.022

[46] Næser K, Savini G, Bregnhøj JF. Corneal powers measured with a rotating Scheimpflug camera. Br J Ophthalmol. 2016;100(9): 1196–200. doi: 10.1136/bjophthalmol-2015-307474

[47] Næser K., Savini G., Bregnhøj J.F. Corneal powers measured with a rotating Scheimpflug camera // Br J Ophthalmol. 2016. Vol. 100, N 9. P. 1196–200. doi: 10.1136/bjophthalmol-2015-307474

[48] Næser K, Savini G, Bregnhøj JF. Corneal powers measured with a rotating Scheimpflug camera. Br J Ophthalmol. 2016;100(9): 1196–200. doi: 10.1136/bjophthalmol-2015-307474

[49] Módis JrL, Szalai E, Kolozsvári B, et al. Keratometry evaluations with the Pentacam high resolution in comparison with the automated keratometry and conventional corneal topography. Cornea. 2012;31(1):36–41. doi: 10.1097/ICO.0b013e318204c666

[50] Módis Jr.L., Szalai E., Kolozsvári B., et al. Keratometry evaluations with the Pentacam high resolution in comparison with the automated keratometry and conventional corneal topography // Cornea. 2012. Vol. 31, N 1. P. 36–41. doi: 10.1097/ICO.0b013e318204c666

[51] Módis JrL, Szalai E, Kolozsvári B, et al. Keratometry evaluations with the Pentacam high resolution in comparison with the automated keratometry and conventional corneal topography. Cornea. 2012;31(1):36–41. doi: 10.1097/ICO.0b013e318204c666

[52] Kulikov AN, Danilenko EV, Kozhevnikov EYu. Comparison of keratometry versions in patients with corneal astigmatism. Russian Ophthalmological Journal. 2022;15(2):84–92. EDN: EXQQCI doi: 10.21516/2072-0076-2022-15-2-supplement-84-92

[53] Куликов А.Н., Даниленко Е.В., Кожевников Е.Ю. Сравнение различных вариантов кератометрии у пациентов с роговичным астигматизмом // Российский офтальмологический журнал. 2022. Т. 15, № 2. С. 84–92. EDN: EXQQCI doi: 10.21516/2072-0076-2022-15-2-supplement-84-92

[54] Kulikov AN, Danilenko EV, Kozhevnikov EYu. Comparison of keratometry versions in patients with corneal astigmatism. Russian Ophthalmological Journal. 2022;15(2):84–92. EDN: EXQQCI doi: 10.21516/2072-0076-2022-15-2-supplement-84-92

[55] Sheridan L, Balaji KG, John MH, Natalka AM. Refractive outcomes after cataract surgery: Scheimpflug keratometry versus standard automated keratometry in virgin corneas. J Cataract Refract Surg. 2011;37(11):1984–1987. doi: 10.1016/j.jcrs.2011.05.031

[56] Sheridan L., Balaji K.G., John M.H., Natalka A.M. Refractive outcomes after cataract surgery: Scheimpflug keratometry versus standard automated keratometry in virgin corneas // J Cataract Refract Surg. 2011. Vol. 37, N 11. P. 1984–1987. doi: 10.1016/j.jcrs.2011.05.031

[57] Sheridan L, Balaji KG, John MH, Natalka AM. Refractive outcomes after cataract surgery: Scheimpflug keratometry versus standard automated keratometry in virgin corneas. J Cataract Refract Surg. 2011;37(11):1984–1987. doi: 10.1016/j.jcrs.2011.05.031

[58] Shammas HJ, Hoffer KJ, Shammas MC. Scheimpflug photography keratometry readings for routine intraocular lens power calculation. J Cataract Refract Surg. 2009;35(2):330–334. doi: 10.1016/j.jcrs.2008.10.041

[59] Shammas H.J., Hoffer K.J., Shammas M.C. Scheimpflug photography keratometry readings for routine intraocular lens power calculation // J Cataract Refract Surg. 2009. Vol. 35, N 2. P. 330–334. doi: 10.1016/j.jcrs.2008.10.041

[60] Shammas HJ, Hoffer KJ, Shammas MC. Scheimpflug photography keratometry readings for routine intraocular lens power calculation. J Cataract Refract Surg. 2009;35(2):330–334. doi: 10.1016/j.jcrs.2008.10.041

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