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Li S, Li X, Liang W, Wu Z, Jia Y, Ma Y, Chu L, Jin T, Li L, Li Q, Qin M. Improving the accuracy of the SRK/T formula in Chinese with implanting less than 10 D IOL calculated by the SRK/T formula: the SRK/T-Li formula. Int Ophthalmol 2024; 44:32. [PMID: 38329567 DOI: 10.1007/s10792-024-03040-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 01/12/2024] [Indexed: 02/09/2024]
Abstract
PURPOSE To explore the accuracy of the improved SRK/T-Li formula in eyes following implantation of intraocular lens (IOL) of less than 10 D as calculated by using the SRK/T formula in Chinese. METHODS A total of 489 eyes from 489 patients with cataracts were included in this study. These patients were divided into a training set (271 patients) and a testing set (218 patients). The IOL power calculated by using SRK/T was less than 10 D. We evaluated the accuracy of the modified SRK/T-Li formula (P = PSRK/T × 0.8 + 2 (P = implanted IOL power; PSRK/T = IOL power calculated by SRK/T)). We evaluated the mean absolute error (MAE), percentage of prediction error (PE) within ± 0.25, ± 0.50, and ± 1.00 D, and the percentage of postoperative hyperopia. RESULTS The MAE values in order of lowest to highest were as follows: 0.412 D (SRK/T-Li), 0.414 D (Barrett Universal II, (BUII)), 0.814 D (SRK/T), and 1.039 D (Holladay 1). The percentage of PE within ± 0.25 D, ± 0.50 D, and ± 1.00 D was 38.99%, 69.27% and 92.66% (BUII), 40.83%, 69.27% and 94.04% (SRK/T-Li), 20.64%, 41.28% and 71.56% (SRK/T), and 7.34%, 16.51% and 53.21% (Holladay 1), respectively. SRK/T-Li had the smallest postoperative hyperopic shift. CONCLUSIONS For Chinese patients with an IOL power of less than 10 D as calculated by using the SRK/T, the SRK/T-Li has good accuracy and is the best choice to reduce postoperative hyperopic shift.
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Affiliation(s)
- Shaowei Li
- Department of Ophthalmology, Aier School of Ophthalmology, Central South University, Changsha, 410083, Hunan, China.
- Department of Ophthalmology, Beijing Aier-Intech Eye Hospital, Number 12 of Panjiayuan Nanli, Chaoyang District, Beijing, 100021, China.
| | - Xinxin Li
- Department of Ophthalmology, Aier School of Ophthalmology, Central South University, Changsha, 410083, Hunan, China
| | - Weiyan Liang
- Department of Ophthalmology, Beijing Aier-Intech Eye Hospital, Number 12 of Panjiayuan Nanli, Chaoyang District, Beijing, 100021, China
| | - Zheming Wu
- Department of Ophthalmology, Guangzhou Aier Eye Hospital, Guangzhou, 510080, Guangdong, China
| | - Yanhong Jia
- Department of Ophthalmology, Nanning Aier Eye Hospital, Nanning, 530000, Guangxi Zhuang Autonomous Region, China
| | - Yanran Ma
- Department of Ophthalmology, Chongqing Aier Eye Hospital, Chongqing, 400000, China
| | - Ling Chu
- Department of Ophthalmology, Shenyang Aier Eye Hospital, Shenyang, 110003, Liaoning, China
| | - Tianru Jin
- Department of Ophthalmology, Shenyang Aier Eye Hospital, Shenyang, 110003, Liaoning, China
| | - Li Li
- Department of Ophthalmology, Nanning Aier Eye Hospital, Nanning, 530000, Guangxi Zhuang Autonomous Region, China
| | - Qiumei Li
- Department of Ophthalmology, Beijing Aier-Intech Eye Hospital, Number 12 of Panjiayuan Nanli, Chaoyang District, Beijing, 100021, China
| | - Ming Qin
- Department of Ophthalmology, Nanning Aier Eye Hospital, Nanning, 530000, Guangxi Zhuang Autonomous Region, China
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Voytsekhivskyy O, Tutchenko L. Comparison of the prediction accuracy of 13 formulas in long eyes. Graefes Arch Clin Exp Ophthalmol 2023; 261:2575-2583. [PMID: 37074410 DOI: 10.1007/s00417-023-06060-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 03/26/2023] [Accepted: 04/04/2023] [Indexed: 04/20/2023] Open
Abstract
PURPOSE To investigate the accuracy of modern intraocular lens (IOL) power calculation formulas in eyes with axial length (AL) ≥ 26.00 mm. METHODS A total of 193 eyes with one type of lens were analysed. An IOL Master 700 (Carl Zeiss Meditec, Jena, Germany) was used for optical biometry. Thirteen formulas and their modifications were evaluated: Barrett Universal II, Haigis, Hoffer QST, Holladay 1 MWK, Holladay 1 NLR, Holladay 2 NLR, Kane, Naeser 2, SRK/T, SRK/T MWK, T2, VRF and VRF-G. The User Group for Laser Interference Biometry lens constants were used for IOL power calculation. The mean prediction error (PE) and its standard deviation (SD), the median absolute error (MedAE), the mean absolute error (MAE) and the percentage of eyes with PEs within ± 0.25 D, ± 0.50 D and < ± 1.00 D were calculated. RESULTS The modern formulas (Barrett Universal II, Hoffer QST, Kane, Naeser 2 and VRF-G) produced the smallest MedAE among all methods (0.30 D, 0.30 D, 0.30 D, 0.29 D and 0.28 D, respectively). The percentage of eyes with a PE within ± 0.50 D ranged from 67.48% to 74.85% for SRK/T and Hoffer QST, Naeser 2 and VRF-G, respectively. CONCLUSIONS Dunn's post hoc test of the absolute errors revealed statistically significant differences (P < 0.05) between some of the newer formulas (Naeser 2 and VRF-G) and the remaining ones. From a clinical perspective the Hoffer QST, Naeser 2 and VRF-G formulas were more accurate predictors of postoperative refraction with the largest proportion of eyes within ± 0.50 D.
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Affiliation(s)
- Oleksiy Voytsekhivskyy
- Kyiv Clinical Ophthalmology Hospital Eye Microsurgery Center, Medical City, Komarov Ave. 3, Kiev, 03680, Ukraine.
| | - Larysa Tutchenko
- Kyiv Clinical Ophthalmology Hospital Eye Microsurgery Center, Medical City, Komarov Ave. 3, Kiev, 03680, Ukraine
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Comparing the accuracy of the new-generation intraocular lens power calculation formulae in axial myopic eyes: a meta-analysis. Int Ophthalmol 2023; 43:619-633. [PMID: 36063246 PMCID: PMC9971158 DOI: 10.1007/s10792-022-02466-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 08/15/2022] [Indexed: 10/14/2022]
Abstract
PURPOSE To compare the accuracy of the new-generation intraocular lens power calculation formulae in axial myopic eyes. METHODS Four databases, PubMed, Web of Science, EMBASE and Cochrane library, were searched to select relevant studies published between Apr 11, 2011, and Apr 11, 2021. Axial myopic eyes were defined as an axial length more than 24.5 mm. There are 13 formulae to participate in the final comparison (SRK/T, Hoffer Q, Holladay I, Holladay II, Haigis for traditional formulae, Barrett Universal II, Olsen, T2, VRF, EVO, Kane, Hill-RBF, LSF for the new-generation formulae). The primary outcomes were the percentage of eyes with a refractive prediction error in ± 0.5D and ± 1.0D. RESULTS A total of 2273 eyes in 15 studies were enrolled in the final meta-analysis. Overall, the new-generation formulae showed a relatively more accurate outcome in comparison with traditional formulae. The percentage of eyes with a predictive refraction error in ± 0.5D (± 1.0D) of Kane, EVO and LSF was higher than 80% (95%), which was only significantly different from Hoffer Q (all P < 0.05). Moreover, another two new-generation formulae, Barrett Universal II and Olsen, had higher percentages than SRK/T, Hoffer Q, Holladay I and Haigis for eyes with predictive refraction error in ± 0.5D and ± 1.0D (all P < 0.05). In ± 0.5D group, Hill-RBF was better than SRK/T (P = 0.02), and Holladay I was better than EVO (P = 0.03) and LSF (P = 0.009), and Hoffer Q had a lower percentage than EVO, Kane, Hill-RBF and LSF (P = 0.007, 0.004, 0.002, 0.03, respectively). Barrett Universal II was better than T2 (P = 0.02), and Hill-RBF was better than SRK/T (P = 0.009). No significant difference was found in other pairwise comparison. CONCLUSION The new-generation formula is more accurate in intraocular lens power calculation for axial myopic eyes in comparison with the third- or fourth-generation formula.
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Atalla AR, El-Agha MS, Osman AA, Khaled MO. Evaluation of Wang-Koch optimisation of axial length for intraocular lens power calculation in myopic eyes. AFRICAN VISION AND EYE HEALTH 2022. [DOI: 10.4102/aveh.v81i1.702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Naik G, Amulya Padmini HM, Dhananjaya KH, Budihal S. A comparative study on accuracy of srk-t and haigis formulas in IOL power calculation in axial myopes undergoing cataract surgery. JOURNAL OF PHARMACY AND BIOALLIED SCIENCES 2022; 14:S907-S910. [PMID: 36110819 PMCID: PMC9469424 DOI: 10.4103/jpbs.jpbs_236_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 03/23/2022] [Accepted: 03/27/2022] [Indexed: 11/06/2022] Open
Abstract
Background and Objective: It has been a significant challenge since the advent of intraocular lens to give the best postoperative visual acuity and prevent refractive surprises due to biometry error. Among myopic eyes, it has been a debate among the various formulas introduced and their efficacy to prevent postoperative refractive surprises. Hence, the need for an accurate formula in high myopic eyes is obligatory. Objectives of the Study: To compare the accuracy of SRK-T and Haigis formulas in IOL power calculation in axial myopic eyes undergoing cataract surgery. Methods: A total of 50 cases with axial length >24 mm were taken up for the study and were examined in detail and error between both formulas were assessed. Results: The mean age of the subjects in the study was 53.50 ± 16.12 years; 27 were males, and 23 were females. The majority of patients had PSC + NS II. Seven out of 50 cases had posterior staphyloma. Most of the patients had average K value in the 44–46-D range. AL of most of the patients (66%) was between 24 and 26 mm. The majority of patients had IOL power >15 D, and 82% (41 eyes) were found to have no post-op complications. Four eyes had severe iritis, and five eyes had striate keratopathy. At the follow-up at 6th week postoperatively, 82% were found to have 6/6–6/9 vision on Snellen's chart. Four eyes had 6/12–6/24 post-op vision, mainly attributed to primary PCO. Five eyes (10%) had <6/24 post op vision at the end of 1 week due to the presence of posterior staphyloma. A higher percentage of eyes in the SRK/T group had a mean error >0.5 D. Upon comparing the mean error between the two groups, P was 0.005; hence, the results are statistically very significant, showing that Haigis formula is better than SRK/T formula in achieving target refraction (−1) in myopic eyes undergoing phacoemulsification. Interpretation and Conclusion: Our study shows that Haigis formula was better than SRK/T formula for achieving the target postoperative refraction in high axial myopes.
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Sajjan S, Naik G, Achar P, Kripalini SH. A descriptive study on visual outcome and intraocular pressure control after trabeculectomy with manual small incision cataract surgery in patients with glaucoma and cataract. JOURNAL OF PHARMACY AND BIOALLIED SCIENCES 2022; 14:S654-S657. [PMID: 36110610 PMCID: PMC9469302 DOI: 10.4103/jpbs.jpbs_144_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 02/11/2022] [Indexed: 11/04/2022] Open
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Delfi D, Virgayanti V, Gunawan H. Comparison between SRK/T and Haigis Formulas on Visual Acuity of Patient with Senile Cataract Post-Phacoemulsification. Open Access Maced J Med Sci 2021. [DOI: 10.3889/oamjms.2021.6308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND: Cataract contributes to the most common cause of blindness worldwide. Cataract surgery is the most performed surgery in the world. To achieve optimal results, pre-operative biometric must be accurate and the use of a formula for measuring the strength of the intraocular lens (IOL) accurately must be used. SRK-T and Haigis are formulas applied in the calculation of IOLs.
AIM: The objective of the study was to determine the evaluation of visual acuity after phacoemulsification using the SRK/T and Haigis formulas.
METHODS: This was an observational prospective analytic study at Medan Baru Eye Hospital from June 2019 to August 2019. Following the examination, patients were required further follow-up on 7–30 days post-phacoemulsification.
RESULTS: The number of subjects was 122 patients (122 eyes), 84 patients were observed, and 38 patients did not come back for control. This study was within the value of p = 0.053. Prediction of refractive errors after phacoemulsification for myopia identified using SRK/T formula was more common, resulting in 3 eyes (75.0%) compared to the Haigis formula. On contrary, the prediction for emetropia was mostly discovered on Haigis formula which amounted to 41 eyes (51.25%) compared to the SRK/T formula.
CONCLUSIONS: There was no significant difference in predicting post-phacoemulsification visual acuity between SRK/T and Haigis formula.
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Li Z, Lian Z, Young CA, Zhao J, Jin G, Zheng D. Accuracy of intraocular lens calculation formulas for eyes with insufficient capsular support. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:324. [PMID: 33708951 PMCID: PMC7944297 DOI: 10.21037/atm-20-3290] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background There is no consensus on which intraocular lens (IOL) power calculation formula provides the best refractive prediction in patients with inadequate capsular support whose anterior ocular anatomic structure differs from that of normal subjects. Therefore, the purpose of this study was to analyze the accuracy and performance of IOL calculation formulas (SRK/T, Holladay 1, Hoffer Q, Haigis, and Barrett Universal II) in predicting postoperative refractive prediction error (PE) for this subgroup of patients. Methods A total of 110 eyes from 110 patients with insufficient capsular support who underwent scleral fixation of an IOL at the Zhongshan Ophthalmic Center from July 1, 2016 to November 30, 2019 were enrolled in this retrospective study. Preoperative optical biometrics were measured with the IOL Master 500 (Carl Zeiss, Oberkochen, Germany). The performance of each formula in predicting PE was compared, and the effect of keratometry and axial length (AL) on PE was evaluated for each formula using univariate and multivariate linear regression analysis. Results The mean age of the included participants was 12.54±9.66 years. The Sanders, Retzlaff, and Manus/theoretical (SRK/T) (-0.25 D) and Holladay 1 (-0.28 D) formulas tended to have minimal postoperative PE compared to the Hoffer Q (-0.62 D), Haigis (-0.67 D), and Barrett Universal II (-0.62 D) formulas (P=0.005). All formulas individually resulted in <70% of eyes within ±1.00 D of the PE. Nevertheless, after constants were optimized, these formulas led to 7.3% to 13.6% of increase within ±1.00 D of the PE. Keratometry and AL were significantly associated with PE for each formula, but the relationship was weakest for SRK/T. Conclusions In eyes with insufficient capsular support, postoperative PE was minimal for the SRK/T formula, which suggested SRK/T to be the best choice, especially when the keratometry and AL of patients are extremely large or small.
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Affiliation(s)
- Zhouyue Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Zhangkai Lian
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Charlotte Aimee Young
- Department of Ophthalmology, Third Affiliated Hospital, Nanchang University, Nanchang, China
| | - Jing Zhao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Guangming Jin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Danying Zheng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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Liu J, Wang L, Chai F, Han Y, Qian S, Koch DD, Weikert MP. Comparison of intraocular lens power calculation formulas in Chinese eyes with axial myopia. J Cataract Refract Surg 2020; 45:725-731. [PMID: 31146930 DOI: 10.1016/j.jcrs.2019.01.018] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Revised: 12/31/2018] [Accepted: 01/15/2019] [Indexed: 10/26/2022]
Abstract
PURPOSE To assess the accuracy of intraocular lens (IOL) power calculation formulas in Chinese eyes with axial lengths (ALs) longer than 26.0 mm. SETTING Department of Cataract Surgery, Shanxi Eye Hospital, China. DESIGN Prospective case series. METHODS This study evaluated (1) two new formulas (Barrett Universal II and Hill-RBF 2.0), (2) three vergence formulas (Haigis, Holladay 1, and SRK/T), and (3) the original and modified Wang-Koch AL adjustment formulas with Holladay 1 and SRK/T. The User Group for Laser Interference Biometry lens constants were used for IOL power calculation. The refractive prediction error was calculated by subtracting the predicted refraction from the actual refraction postoperatively. The mean numerical error (MNE), percentage of eyes with hyperopic outcomes, and mean absolute error (MAE) were determined. RESULTS The study comprised 136 eyes. The Barrett and Hill-RBF formulas had MNEs close to zero (-0.09 D to 0.03 D), the Haigis, Holladay 1, and SRK/T produced hyperopic MNEs (0.25 to 0.70 D), and the original and modified Wang-Koch AL adjustment formulas induced myopic MNEs (-0.48 to -0.22 D). The original Wang-Koch formulas produced significantly lower percentages of eyes with hyperopic outcomes (15% to 18%) than all other formulas (28% to 91%). There were no significant differences in MAEs between the Barrett, Hill-RBF, Haigis, and original and modified Wang-Koch adjustment with the Holladay 1 (0.32 to 0.41 D). CONCLUSION The performances of the Barrett and Hill-RBF were comparable in long eyes. The incidence of hyperopic outcome with the Wang-Koch AL adjustment formula was significantly lower than other formulas.
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Affiliation(s)
- Jiewei Liu
- Shanxi Eye Hospital, Taiyuan, Shanxi Province, China.
| | - Li Wang
- Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA
| | - Feiyan Chai
- Shanxi Eye Hospital, Taiyuan, Shanxi Province, China
| | - Yu Han
- Shanxi Eye Hospital, Taiyuan, Shanxi Province, China
| | - Suqin Qian
- Changsha Vigor Pediatrics, Changsha, Hunan Province, China
| | - Douglas D Koch
- Cullen Eye Institute, Baylor College of Medicine, Houston, Texas, USA
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Skrzypecki J, Grabska-Liberek I, Guszkowska M, Izdebska J, Szaflik JP. Immersion Biometry for Intraocular Lens Power Calculation with Fourth-Generation Formulas. Clin Ophthalmol 2020; 14:2159-2162. [PMID: 32801625 PMCID: PMC7397473 DOI: 10.2147/opth.s259078] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 06/23/2020] [Indexed: 11/25/2022] Open
Abstract
Background Fourth-generation formulas for intraocular lens power calculations, including the Barrett Universal II formula, the Olsen formula or the Holladay 2 formula, were thoroughly validated with optical biometry measurements. They precisely predict the effective lens position not only in normal eyes but also in eyes with unusual anatomy. However, in the setting of dense nuclear or posterior subcapsular cataracts, optical biometers fail to obtain accurate measurements and third-generation formulas, i.e. the Hoffer Q or the SRK/T, combined with ultrasound measurements are a method of choice. Considering that optical biometry was fine-tuned to immersion ultrasound, we hypothesize that fourth-generation formulas will yield precise intraocular lens power calculations with immersion ultrasound measurements. Methods We retrospectively analyzed 50 eyes of 50 patients who underwent uneventful cataract surgery. All patients had intraocular lens power calculated based on immersion ultrasound measurements. Refractive error predictions were compared between third-generation formulas and fourth-generation formulas. Results There were no statistically significant differences in the median absolute error between formulas. In the study, 86%, 88%, 86%, 84%, 88% and 80% of eyes were within 1 D of target refraction for the SRK/T, the Barrett II, the Hoffer Q, the Holladay 1, the Holladay 2 and the Olsen formula respectively. Conclusion Fourth-generation formulas combined with immersion ultrasound produced similar results to third-generation formulas. However, the percentage of eyes within 1 D of target refraction remains inferior to previously reported results for optical biometry measurements.
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Affiliation(s)
- Janusz Skrzypecki
- Department of Ophthalmology, Medical University of Warsaw, Warsaw, Poland.,Department of Experimental Physiology and Pathophysiology, Medical University of Warsaw, Warsaw, Poland
| | - Iwona Grabska-Liberek
- Department of Ophthalmology, Medical Centre for Postgraduate Education, Warsaw, Poland
| | - Maria Guszkowska
- Department of Ophthalmology, Medical University of Warsaw, Warsaw, Poland
| | - Justyna Izdebska
- Department of Ophthalmology, Medical University of Warsaw, Warsaw, Poland
| | - Jacek P Szaflik
- Department of Ophthalmology, Medical University of Warsaw, Warsaw, Poland
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Ohr MP, Wisely CE. Refractive outcomes and accuracy of IOL power calculation with the SRK/T formula for sutured, scleral-fixated Akreos AO60 intraocular lenses. Graefes Arch Clin Exp Ophthalmol 2020; 258:2125-2129. [PMID: 32504099 DOI: 10.1007/s00417-020-04721-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 04/17/2020] [Accepted: 04/23/2020] [Indexed: 11/28/2022] Open
Abstract
BACKGROUND Scleral fixation of intraocular lenses has become a popular procedure for treating aphakia in the absence of capsular support. However, the lens formulas used to predict refractive outcomes were designed for in-the-bag lens placement. This study evaluates the accuracy of the SRK/T formula in predicting a target postoperative refraction when suturing a scleral-fixated intraocular lens (IOL) implant 3 mm posterior to the limbus. METHODS This is a retrospective, case series including 20 eyes of 20 patients who underwent scleral fixation of Akreos AO60 IOLs (Bausch & Lomb, Rochester, NY) by a single surgeon at the OSU Wexner Medical Center. Preoperative measurements were performed with optical biometry, and IOL power was calculated with the SRK/T formula. Following surgery, the actual refractive spherical equivalent (SE) was performed and compared with the preoperative prediction. Prediction error (PE), defined as the deviation of actual postoperative SE refraction in diopters (D) from preoperative predicted SE refraction, was the primary outcome measure. RESULTS The mean attempted (predicted) SE was - 1.12 D (± 0.87). Mean achieved SE was - 0.96 D (± 1.04). Mean PE (actual postoperative SE versus predicted preoperative SE) was 0.16 D (± 0.69). A total of 9 eyes (45%) were within ± 0.5 D of the predicted SE, 16 eyes (80%) were within ± 1.0 D, and all 20 eyes (100%) were within ± 1.5 D. CONCLUSION IOL power calculation using the SRK/T formula with optical biometry demonstrates reliable postoperative refractive outcomes in patients undergoing scleral fixation of an IOL (Akreos AO60). Further studies are needed to refine the predictive value of the SRK/T and other formulas for application in scleral fixation of IOLs.
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Affiliation(s)
- Matthew P Ohr
- Department of Ophthalmology, The Ohio State University, 915 Olentangy River Road Suite 5000, Columbus, OH, 43212, USA.
| | - C Ellis Wisely
- Department of Ophthalmology, Duke University, Durham, NC, USA
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Effect of the ratio of axial length to keratometry on SRK/T intraocular lens power calculations for eyes with long axial lengths. Sci Rep 2019; 9:19515. [PMID: 31863002 PMCID: PMC6925128 DOI: 10.1038/s41598-019-56116-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 12/08/2019] [Indexed: 12/20/2022] Open
Abstract
This retrospective study explored the effect of the ratio of axial length (AL) to average keratometry (K) on intraocular lens power calculation in long eyes. The clinical records of eyes that had an AL of 26.0 mm or longer, and underwent cataract surgery with intraocular lens implantations, were reviewed. This study was approved by the institutional review board of Miyata Eye Hospital. Preoperative biometry data were obtained using optical low-coherence reflectometry. Prediction errors in the use of the SRK/T formulas were obtained from manifest refraction spherical equivalents one month postoperatively. Significant factors inducing prediction errors were examined using stepwise multiple regression analysis with descriptive factors of AL, K value, and their ratio (AL/K). Clinical records related to 49 long eyes of 49 patients, and 93 eyes of 93 patients with normal AL, were evaluated. Stepwise multiple regression analysis revealed that the AL/K was a significant factor increasing the prediction errors (P = 0.0003). With the regression equation, 98% of prediction errors with the use of the SRK/T formula were within ±1.00 D of differences. For our sample of 49 long eyes, the ratio of AL to K was a significant factor inducing hyperopic prediction errors with the use of SRK/T for long eyes.
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Calculation of Axial Length Using a Single Group Refractive Index versus Using Different Refractive Indices for Each Ocular Segment. Ophthalmology 2019; 126:663-670. [DOI: 10.1016/j.ophtha.2018.12.046] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 12/21/2018] [Accepted: 12/24/2018] [Indexed: 12/21/2022] Open
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Wang-Koch axial length adjustment for the Holladay 2 formula in long eyes. J Cataract Refract Surg 2018; 44:1291-1292. [DOI: 10.1016/j.jcrs.2018.06.057] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 06/28/2018] [Indexed: 11/19/2022]
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Nabil KM. Accuracy of minus power intraocular lens calculation using OKULIX ray tracing software. Int Ophthalmol 2018; 39:1803-1808. [PMID: 30141002 DOI: 10.1007/s10792-018-1007-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 08/17/2018] [Indexed: 11/25/2022]
Abstract
PURPOSE The purpose of this retrospective study was to assess the accuracy of minus power intraocular lens calculation using partial coherence interferometry and OKULIX ray tracing software. METHODS We included 25 consecutive, myopic eyes with axial length ≥ 30 mm (25 patients, 13 males and 12 females, and 57.6 ± 10.3 years old), which underwent phacoemulsification and implantation of a minus power intraocular lens in the capsular bag. Axial length measurement and corneal topography were performed using the OA-1000 optical biometer and Topographic Modeling System TMS-5, respectively. The IOL power was calculated using SRK/T formula and OKULIX ray tracing software. The implanted IOL power was chosen based on OKULIX ray tracing software calculation aiming for - 2 diopters (D) of myopia. RESULTS SRK/T calculated IOL power (- 6.3 ± 2.8 D) showed statistically significant difference compared to OKULIX calculated IOL power (- 4.7 ± 2.6 D), rs 0.994 p < 0.001. The expected refraction with implanted IOL was - 1.7 ± 0.9 D based on OKULIX ray tracing software calculation. A statistically significant difference was reported between implanted IOL and OKULIX calculated IOL power (2.7 ± 1.4 D), rs 0.981 p < 0.001. A statistically significant difference was reported between the expected refraction with implanted IOL and the achieved spherical refraction at 1 month postoperatively (1.4 ± 0.7 D), rs 0.77 p < 0.001. The achieved spherical refraction at 1 month postoperatively was 0.2 ± 0.2 D. CONCLUSIONS Although OKULIX ray tracing software yielded more accurate minus power intraocular lens calculation in extreme myopia, compared to SRK/T formula, yet it still shows tendency toward hyperopia.
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Affiliation(s)
- Karim Mahmoud Nabil
- Department of Ophthalmology, Faculty of Medicine, University of Alexandria, 19 Amin Fekry Street, Raml station, Alexandria, 21523, Egypt.
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Wang Q, Jiang W, Lin T, Wu X, Lin H, Chen W. Meta-analysis of accuracy of intraocular lens power calculation formulas in short eyes. Clin Exp Ophthalmol 2017; 46:356-363. [DOI: 10.1111/ceo.13058] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 08/24/2017] [Accepted: 08/31/2017] [Indexed: 11/29/2022]
Affiliation(s)
- Qiwei Wang
- State Key Laboratory of Ophthalmology; Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou; People's Republic of China
| | - Wu Jiang
- Department of Colorectal Surgery; Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine; Guangzhou People's Republic of China
| | - Tiao Lin
- The First Affiliated Hospital; Sun Yat-sen University; Guangzhou People's Republic of China
| | - Xiaohang Wu
- State Key Laboratory of Ophthalmology; Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou; People's Republic of China
| | - Haotian Lin
- State Key Laboratory of Ophthalmology; Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou; People's Republic of China
| | - Weirong Chen
- State Key Laboratory of Ophthalmology; Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou; People's Republic of China
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Geggel HS. Comparison of formulas and methods for high myopia patients requiring intraocular lens powers less than six diopters. Int Ophthalmol 2017. [DOI: 10.1007/s10792-017-0611-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Fouad M, El Din Farahat H, Said Ahmed K, Gad Marey H. Intraocular lens master optical biometry versus conventional ultrasound biometry in intraocular lens power calculations in highly myopic eyes. ACTA ACUST UNITED AC 2017. [DOI: 10.4103/1110-2098.215434] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Güler E, Kulak AE, Totan Y, Yuvarlak A, Hepşen İF. Comparison of a new optical biometry with an optical low-coherence reflectometry for ocular biometry. Cont Lens Anterior Eye 2016; 39:336-41. [DOI: 10.1016/j.clae.2016.06.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Revised: 04/26/2016] [Accepted: 06/07/2016] [Indexed: 11/25/2022]
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Fixation Stability and Refractive Error After Cataract Surgery in Highly Myopic Eyes. Am J Ophthalmol 2016; 169:89-94. [PMID: 27325397 DOI: 10.1016/j.ajo.2016.06.022] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 06/05/2016] [Accepted: 06/11/2016] [Indexed: 11/21/2022]
Abstract
PURPOSE To analyze the refractive error in highly myopic eyes after cataract surgery and investigate the possible impact of fixation stability on it. DESIGN Secondary data analysis from a previous prospective study. METHODS Clinical data of 98 eyes of 98 consecutive patients with high myopia and 42 eyes of 42 controls, which underwent cataract surgery, were analyzed. Refractive error was calculated 1 month after surgery based on both Sanders-Retzlaff-Kraff theoretic (SRK/T) and Holladay 1 formulas. Fixation stability was evaluated using the Macular Integrity Assessment microperimeter system, which assessed the fixation pattern in terms of 63% and 95% of the bivariate contour ellipse area (BCEA). Multiple linear regression analysis was performed to identify independent predictors of postoperative refractive error. RESULTS The highly myopic cataract group had greater hyperopic refractive errors (P < .001 for both formulas) and larger 63% and 95% BCEA values (P = .033 and P = .034) than the control group. In the highly myopic group, the factors 63% or 95% BCEA were positively correlated with the postoperative refractive error (SRK/T formula, r = 0.383, P < .001 and r = 0.320, P = .002, respectively). Multiple linear regression analysis showed that with the SRK/T formula, postoperative refractive error in highly myopic eyes was significantly correlated with axial length (β = 0.491, P < .001), 63% BCEA (β = 0.181, P = .045), and corneal curvature (β = -0.190, P = .024). The refractive error was no longer associated with corneal curvature after using the Holladay 1 formula. CONCLUSIONS Highly myopic eyes usually had hyperopic refractive errors after cataract surgery. Fixation stability might serve as an important determinant of postoperative refractive errors in this population.
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Abstract
PURPOSE OF REVIEW Cataract surgery in high myopes is challenging. Using third-generation intraocular lens (IOL) formulas, without adjustments, hyperopic refractive outcomes are common. We discuss these issues, focusing on the various lens formulas and transformations that have improved postoperative accuracy. RECENT FINDINGS Axial length measurement error has been largely overcome by the use of optical interferometry. Despite this, consistent hyperopic errors are still reported. We reviewed the postoperative refraction results compared with the predicted refractions using: standard formulas (Holladay 1, SRK/T, Hoffer Q, and Haigis) with manufacturers' optical lens constants, the User Group for Laser Interference Biometry (ULIB) constants, manufacturers' constants with axial length adjustment method, and fourth-generation IOL formulas (Barrett Universal II, Holladay 2, and Olsen). SUMMARY Improved predictive results is obtained with the Barrett Universal II (software constants), Haigis (ULIB), SRK/T, Holladay 2 (software constants), and Olsen (software constants) formulas in eyes with axial lengths greater than 26.0 mm and IOL powers greater than 6.0 D. In eyes with axial lengths greater than 26.0 mm and IOL less than 6.0 D, the Barrett Universal II formula (software constants) and the Haigis (axial length adjusted) and Holladay 1 formulas (axial length-adjusted) should be used.
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Accuracy of Intraocular Lens Power Calculation Formulas for Highly Myopic Eyes. J Ophthalmol 2016; 2016:1917268. [PMID: 27119018 PMCID: PMC4828549 DOI: 10.1155/2016/1917268] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 03/10/2016] [Accepted: 03/13/2016] [Indexed: 11/18/2022] Open
Abstract
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.
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Montes de Oca I, Gökce SE, Hallahan K, Wang L, Koch DD. IOL Calculations in Short, Long, and Postrefractive Eyes. Int Ophthalmol Clin 2016; 56:49-70. [PMID: 27257722 DOI: 10.1097/iio.0000000000000119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
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Abulafia A, Barrett GD, Rotenberg M, Kleinmann G, Levy A, Reitblat O, Koch DD, Wang L, Assia EI. Intraocular lens power calculation for eyes with an axial length greater than 26.0 mm: Comparison of formulas and methods. J Cataract Refract Surg 2015; 41:548-56. [DOI: 10.1016/j.jcrs.2014.06.033] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Revised: 06/04/2014] [Accepted: 06/06/2014] [Indexed: 10/24/2022]
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Oh J, Choi JS. Accuracy of Intraocular Lens Power Calculations According to Corneal Curvature in Short Eyes. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2014. [DOI: 10.3341/jkos.2014.55.6.826] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- JeongJae Oh
- Department of Ophthalmology, Saevit Eye Hospital, Goyang, Korea
| | - Jin Seok Choi
- Department of Ophthalmology, Saevit Eye Hospital, Goyang, Korea
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Biometric measurements in highly myopic eyes. J Cataract Refract Surg 2013; 39:180-7. [DOI: 10.1016/j.jcrs.2012.08.064] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2012] [Revised: 07/25/2012] [Accepted: 08/21/2012] [Indexed: 11/18/2022]
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Yokoi T, Moriyama M, Hayashi K, Shimada N, Ohno-Matsui K. Evaluation of refractive error after cataract surgery in highly myopic eyes. Int Ophthalmol 2013; 33:343-8. [DOI: 10.1007/s10792-012-9690-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2012] [Accepted: 12/07/2012] [Indexed: 10/27/2022]
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Optimizing intraocular lens power calculations in eyes with axial lengths above 25.0 mm. J Cataract Refract Surg 2011; 37:2018-27. [DOI: 10.1016/j.jcrs.2011.05.042] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 05/13/2011] [Accepted: 05/15/2011] [Indexed: 11/22/2022]
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Abstract
Purpose To study the accuracy of different recent intraocular lens (IOL) calculation formulas in predicting a target postoperative refraction ± 1.0D (Diopters) in patients with long eyes (axial length ≥ 26.0 mm) undergoing phacoemulsification. Materials and Methods This study comprised 127 eyes of 87 patients who presented with cataract and axial eye length ≥ 26 mm. Before phacoemulsification and IOL implantation; axial length measurement using immersion ultrasound A-scan technique, and autokeratometry with or without computerized corneal topography for K readings were done. The IOL power was calculated using four formulas, namely the SRK-T, Hoffer-Q, Holladay-2, and Haigis formulas. Four months after surgery, refraction was done. Differences between actual postoperative refraction and assumed target refraction using the different formulas were analyzed. P < 0.05 was considered statistically significant. Results In all 127 eyes, the mean axial length was 31.71 mm (range, 26.06–37.11 mm) and the mean K was 44.68 D (range, 40.05–55.14D). The mean preoperative spherical equivalent (SE) was −17.52D (range, −12.25 to −30.50D). After surgery, the mean spherical equivalent was −0.8 ± 0.83D (range, +1.25 to −3.75D). The mean postoperative refractive SE when implanting a plus power IOLs was −0.3 ± 0.51D (P < 0.001) while the mean postoperative refractive SE when implanting a minus power IOLs was +1.21 ± 0.11D denoting a highly significant tendency toward hyperopia (P < 0.001). Concerning the minus power group, most postoperative refractive error was within +1.0 to +2.0D in the actual implanted IOL and in all other formula calculated IOL power. However, Haigis formula showed the least deviation while SRK-T and other formulas showed a greater tendency toward hyperopia. Conclusions In eyes with high axial myopia, the performance of SRK-T, Hoffer-Q, Holladay-2 and Haigis formulas are comparable in low plus-powered IOL implantation. Haigis formula is the best formula when minus power IOL is implanted.
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Affiliation(s)
- Asaad A Ghanem
- Ophthalmology Center, Faculty of Medicine, Mansoua University, Mansoura, Egypt
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Dooley I, Charalampidou S, Nolan J, Loughman J, Molloy L, Beatty S. Estimation of effective lens position using a method independent of preoperative keratometry readings. J Cataract Refract Surg 2011; 37:506-12. [PMID: 21333875 DOI: 10.1016/j.jcrs.2010.09.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2010] [Revised: 09/19/2010] [Accepted: 09/28/2010] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate the validity of a keratometry (K)-independent method of estimating effective lens position (ELP) before phacoemulsification cataract surgery. SETTING Institute of Eye Surgery, Whitfield Clinic, Waterford, Ireland. DESIGN Evaluation of diagnostic test or technology. METHODS The anterior chamber diameter and corneal height in eyes scheduled for cataract surgery were measured with a rotating Scheimpflug camera. Corneal height and anterior chamber diameter were used to estimate the ELP in a K-independent method (using the SRK/T [ELP(rs)] and Holladay 1 [ELP(rh)] formulas). RESULTS The mean ELP was calculated using the traditional (mean ELP(s) 5.59 mm ± 0.52 mm [SD]; mean ELP(h) 5.63 ± 0.42 mm) and K-independent (mean ELP(rs) 5.55 ± 0.42 mm; mean ELP(rh) ± SD 5.60 ± 0.36 mm) methods. Agreement between ELP(s) and ELP(rs) and between ELP(h) and ELP(rh) were represented by Bland-Altman plots, with mean differences (± 1.96 SD) of 0.06 ± 0.65 mm (range -0.59 to +0.71 mm; P=.08) in association with ELP(rs) and -0.04 ± 0.39 mm (range -0.43 to +0.35 mm; P=.08) in association with ELP(rh). The mean absolute error for ELP(s) versus ELP(rs) estimation and for ELP(h) versus ELP(rh) estimation was 0.242 ± 0.222 mm (range 0.001 to 1.272 mm) and 0.152 ± 0.137 mm (range 0.001 to 0.814 mm), respectively. CONCLUSION This study confirms that the K-independent ELP estimation method is comparable to traditional K-dependent methods and may be useful in post-refractive surgery patients.
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Affiliation(s)
- Ian Dooley
- Department of Ophthalmology, Waterford Regional Hospital, Institute of Eye Surgery, Dublin, Ireland.
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Charalampidou S, Dooley I, Molloy L, Beatty S. Value of dual biometry in the detection and investigation of error in the preoperative prediction of refractive status following cataract surgery. Clin Exp Ophthalmol 2010; 38:255-65. [PMID: 20447121 DOI: 10.1111/j.1442-9071.2010.02211.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
PURPOSE To report the value of dual biometry in the detection of biometry errors. METHODS Study 1: retrospective study of 224 consecutive cataract operations. The intraocular lens power calculation was based on immersion biometry. Study 2: immersion biometry was compared with optical coherence biometry (OCB) in terms of axial length, anterior chamber depth, keratometry readings and the recommended lens power to achieve emmetropia. Study 3: prospective study of 61 consecutive cataract operations. Both immersion and OCB were performed, but lens power calculation was based on the latter. RESULTS Study 1: 115 (86%), 101 (75.4%), 90 (67.2%) and 50 (37.3%) of postoperative spherical equivalents were within +/-1.5 dioptres (D), +/-1.25 D, +/-1 D and +/-0.5 D of the target, respectively. Study 2: excellent agreement between axial length readings, anterior chamber depth readings and keratometry readings by immersion biometry and OCB was observed (reflected in a mean bias of -0.065 mm, -0.048 mm and +0.1803 D, respectively, in association with OCB). Agreement between the lens power recommended by each technique to achieve emmetropia was poor (mean bias of +1.16 D in association with OCB), but improved following appropriate modification of lens constants in the Accutome A-scan software (mean bias with OCB = -0.4 D). Study 3: 37 (92.5%) and 23 (57.5%) of operated eyes achieved a postoperative refraction within +/-1 D and +/-0.5 D of target, respectively. CONCLUSION Systematic errors in biometry can exist, in the presence of acceptable postoperative refractive results. Dual biometry allows each biometric parameter to be scrutinized in isolation, and identify sources of error that may otherwise go undetected.
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Affiliation(s)
- Sofia Charalampidou
- Department of Ophthalmology, Waterford Regional Hospital, Waterford, Ireland.
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Lee YE, Choi KR, Jun RM. Accuracy of Intraocular Lens Power Calculations According to the Formulas and Anterior Chamber Depth in Short Eyes. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2010. [DOI: 10.3341/jkos.2010.51.10.1338] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Young-Eun Lee
- Department of Ophthalmology, Ewha Womans University School of Medicine, Seoul, Korea
| | - Kyu-Ryong Choi
- Department of Ophthalmology, Ewha Womans University School of Medicine, Seoul, Korea
| | - Roo Min Jun
- Department of Ophthalmology, Ewha Womans University School of Medicine, Seoul, Korea
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Intraocular lens power calculation and optimized constants for highly myopic eyes. J Cataract Refract Surg 2009; 35:1575-81. [PMID: 19683155 DOI: 10.1016/j.jcrs.2009.04.028] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2008] [Revised: 03/31/2009] [Accepted: 04/01/2009] [Indexed: 12/18/2022]
Abstract
PURPOSE To determine the accuracy of intraocular lens (IOL) power calculations in eyes with high myopia and to suggest adjusted constants for these cases. SETTING Centre for Ophthalmology, Eberhard-Karls-University, Tuebingen, Germany. METHODS Patients with high myopia having phacoemulsification with implantation of an AcrySof MA60MA IOL (power range +5.00 to -5.00 diopters [D]) were evaluated. Optical biometry (IOLMaster) and IOL calculations were performed before and after IOL implantation. Because of different optic principal planes of negative-diopter and positive-diopter IOLs, separate constants were calculated for these groups. RESULTS Fifty eyes (32 patients) were evaluated. Thirty eyes (mean AL 31.15 mm +/- 1.69 [SD]) had implantation of a positive-diopter IOL (mean power +3.10 +/- 1.50 D) and 18 eyes (mean AL 33.20 +/- 2.25 mm), a negative-diopter IOL (mean power -3.20 +/- 1.70 D). Postoperatively, the mean spherical equivalent was -1.42 +/- 1.33 D and -0.41 +/- 1.81 D, respectively. The difference in optimized constants between positive- and negative-diopter IOLs was significant for all formulas. Power calculation with the SRK II formula showed a wide range of deviation of postoperative refraction from target refraction. Calculation with the Haigis, SRK/T, Holladay 1, and Hoffer Q formulas showed a mean deviation of 0.00 D with an SD of 0.88, 0.92, 1.03, and 1.15, respectively. CONCLUSIONS Results indicate that the SRK II formula cannot be recommended for IOL power calculation in highly myopic patients. With optimized constants, the SRK/T, Haigis, Hoffer Q, and Holladay 1 formulas produced small deviation of postoperative refraction from target refraction.
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Zuberbuhler B, Seyedian M, Tuft S. Phacoemulsification in eyes with extreme axial myopia. J Cataract Refract Surg 2009; 35:335-40. [DOI: 10.1016/j.jcrs.2008.10.044] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Revised: 10/18/2008] [Accepted: 10/20/2008] [Indexed: 10/21/2022]
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Jun RM, Kang SY, Kim BY. Accuracy of Biometry and Intraocular Lens Power Calculation With Partial Coherence Interferometry in High Myopia. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2008. [DOI: 10.3341/jkos.2008.49.11.1746] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Roo Min Jun
- Department of Ophthalmology, School of Medicine, Ewha Womans University, Seoul, Korea
| | - Soo Yeon Kang
- Department of Ophthalmology, Kim's Eye Hospital, Myung-gok Ophthalmologic Research Center, Seoul, Korea
| | - Byoung Yeop Kim
- Department of Ophthalmology, Kim's Eye Hospital, Myung-gok Ophthalmologic Research Center, Seoul, Korea
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MacLaren RE, Natkunarajah M, Riaz Y, Bourne RRA, Restori M, Allan BDS. Biometry and formula accuracy with intraocular lenses used for cataract surgery in extreme hyperopia. Am J Ophthalmol 2007; 143:920-931. [PMID: 17524766 DOI: 10.1016/j.ajo.2007.02.043] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2006] [Revised: 02/11/2007] [Accepted: 02/14/2007] [Indexed: 10/23/2022]
Abstract
PURPOSE To audit intraocular lens (IOL) power predictions for cataract surgery in extreme hyperopia and to compare the accuracy across different biometry formulae and IOL types. DESIGN A retrospective analysis of 76 eyes from 56 patients undergoing cataract surgery with IOLs ranging in power from 30 to 35 diopters (D). METHODS Axial lengths, corneal powers and anterior chamber depths were measured with ultrasound or optical methods, and the IOLMaster (Carl Zeiss Meditech, Inc, Dublin, California, USA) software was used to predict the refractive outcome for each IOL used. Differences between the predicted and actual postoperative refraction were then analyzed for each formula. RESULTS In practice, 55% of patients were within +/-1.0 D of the refraction predicted by their surgeon. In theory, the Haigis formula would have given the smallest mean refractive error (+0.51 +/- 0.12 D), followed by the Hoffer Q (-0.70 +/- 0.14 D), Holladay 1 (-1.11 +/- 0.13 D), and SRK/T formulae (-1.45 +/- 0.14 D). The Haigis formula overpredicted the lens power required, which would have generated a myopic result. The other formulae underpredicted the lens power required and would have generated a hyperopic result. There was a significant difference between lens designs: the Haigis was more accurate for open-loop, whereas the Hoffer Q was more accurate for plate-haptic lenses. The anterior chamber depth measurement could also be used to predict changes in intraocular pressure after surgery. CONCLUSION This represents the largest published series to date of biometry predictions for cataract surgery in extreme hyperopia and confirms the Haigis formula to be the most accurate. A consistent difference between open-loop and plate-haptic lenses suggests that haptic design may influence the effective lens position in very small eyes. We further propose a simple formula to optimize the Haigis and Hoffer Q formulae in patients with extreme hyperopia.
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Jeoung JW, Chung H, Yu HG. Factors influencing refractive outcomes after combined phacoemulsification and pars plana vitrectomy. J Cataract Refract Surg 2007; 33:108-14. [PMID: 17189804 DOI: 10.1016/j.jcrs.2006.09.017] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2006] [Accepted: 09/14/2006] [Indexed: 11/21/2022]
Abstract
PURPOSE To evaluate the factors influencing the refractive outcomes of combined phacoemulsification, foldable intraocular lens (IOL) implantation, and pars plana vitrectomy (PPV). SETTING Department of Ophthalmology, Seoul National University Hospital, Seoul, Korea. METHODS One hundred fifty-four consecutive patients who had combined phacoemulsification, IOL implantation, and PPV between September 2001 and August 2004 were enrolled in a prospective study. Refractive, keratometric, and axial length measurements were performed preoperatively and 4 months postoperatively. The factors influencing the postoperative refractive outcomes were analyzed. RESULTS The mean refractive prediction error (ie, actual minus predicted spherical equivalent [SE]) was -0.06 diopters (D) +/- 0.75 (SD). In long eyes (preoperative axial length more than 24.5 mm), the mean predicted SE and actual SE were -0.81 +/- 0.76 D and -1.24 +/- 0.79 D, respectively; the difference was significantly different (P = .001, paired t test). Patients with a preoperative visual acuity worse than 5/200 and those with preoperative foveal detachment had a significant postoperative myopic shift (P = 0.024 and P = 0.002, respectively; paired t test). Postoperative refractive error was not influenced by the intraocular air or gas tamponade during surgery (P = 0.336, paired t test). CONCLUSIONS The combined surgery included a small biometric error that was within the tolerable range in most cases. However, myopic shifts developed in patients with long axial lengths, poor preoperative visual acuity, and the preoperative presence of foveal detachment.
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Affiliation(s)
- Jin Wook Jeoung
- Department of Ophthalmology, Seoul National University Hospital and Seoul National University College of Medicine, Seoul, Korea
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Teichmann KD. Biometry accuracy. J Cataract Refract Surg 2006; 32:191. [PMID: 16564980 DOI: 10.1016/j.jcrs.2005.12.047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2005] [Indexed: 10/24/2022]
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