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Chen Y, Fang Y, Zhao J, He W, Ma B, Zhu X. Influence of Lens Thickness on Accuracy of Kane, Hill-RBF 3.0, Barrett Universal II, Emmetropia Verifying Optical, and Pearl-DGS Formulas in Eyes with Nonhigh Myopia and High Myopia. Curr Eye Res 2024; 49:605-614. [PMID: 38363071 DOI: 10.1080/02713683.2024.2316717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 02/05/2024] [Indexed: 02/17/2024]
Abstract
PURPOSE To investigate the influence of lens thickness (LT) on accuracy of Kane, Hill-RBF 3.0 Barrett Universal II (BUII), Emmetropia Verifying Optical (EVO), and Pearl-DGS formulas in eyes with different axial lengths (AL). METHODS The prospective cohort study was conducted at Eye and ENT Hospital of Fudan University. Patients who had uneventful cataract surgery between March 2021 and July 2023 were recruited. Manifest refraction was conducted two-month post-surgery. Eyes were divided into 4 groups based on AL: short (<22mm), medium (22-24.5 mm), medium long (24.5-26mm) and very long (≥26mm). In each AL group, eyes were then divided into 3 subgroups based on the LT measured with IOLmaster700: thin (<4.5 mm), medium (4.5-5.0 mm), and thick (≥ 5 mm). The influence of LT on accuracy of Kane, Hill-RBF 3.0, BUII, EVO, and Pearl-DGS formulas were investigated in each AL group. RESULTS A total of 327 eyes from 327 patients were analyzed, with 64, 102, 73 and 88 eyes in each AL group, respectively. In eyes with AL < 24.5 mm, myopic PE was significantly associated with greater LT using all the 5 formulas (all p < 0.05). Backward stepwise multivariate regression analyses revealed that LT was an important influencing factor for PE in all 5 formulas, particularly in eyes with AL <24.5 mm. In eyes with AL <24.5 mm and LT > 5.0 mm, PE of all 5 formulas calculated with the optional parameter LT were more myopic than those calculated without LT. CONCLUSIONS Thicker LT was associated with more myopic PE among eyes with AL <24.5 mm when using all 5 formulas. Further optimization of current formulas is necessary, especially for eyes with short AL and thick LT.
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Affiliation(s)
- Yuxi Chen
- Eye Institute and Department of Ophthalmology, Eye and ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia, Fudan University, Shanghai, China
- Key Laboratory of Myopia, Chinese Academy of Medical Science, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Yanwen Fang
- Eye Institute and Department of Ophthalmology, Eye and ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia, Fudan University, Shanghai, China
- Key Laboratory of Myopia, Chinese Academy of Medical Science, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Jing Zhao
- Eye Institute and Department of Ophthalmology, Eye and ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia, Fudan University, Shanghai, China
- Key Laboratory of Myopia, Chinese Academy of Medical Science, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Wenwen He
- Eye Institute and Department of Ophthalmology, Eye and ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia, Fudan University, Shanghai, China
- Key Laboratory of Myopia, Chinese Academy of Medical Science, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
| | - Bo Ma
- Shaanxi Eye Hospital, Xi'an People's Hospital (Xi'an Fourth Hospital), Affiliated Guangren Hospital, School of Medicine, Xi'an Jiaotong University, Shaanxi Province, China
| | - Xiangjia Zhu
- Eye Institute and Department of Ophthalmology, Eye and ENT Hospital, Fudan University, Shanghai, China
- NHC Key Laboratory of Myopia, Fudan University, Shanghai, China
- Key Laboratory of Myopia, Chinese Academy of Medical Science, Shanghai, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, China
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Yu J, Zhao G, Lei CS, Wan T, Ning R, Xing W, Ma X, Pan H, Savini G, Schiano-Lomoriello D, Zhou X, Huang J. Repeatability and reproducibility of a new fully automatic measurement optical low coherence reflectometry biometer and agreement with swept-source optical coherence tomography-based biometer. Br J Ophthalmol 2024; 108:673-678. [PMID: 37142332 DOI: 10.1136/bjo-2023-323268] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 04/13/2023] [Indexed: 05/06/2023]
Abstract
AIMS To assess the repeatability and reproducibility of the ocular measurements obtained with the Suoer SW-9000 μm Plus, a new fully automatic biometer based on optical low coherence reflectometry (OLCR) biometer, and to compare them to those obtained by a swept-source optical coherence tomography (SS-OCT)-based biometer. METHODS This prospective study consisted of 115 eyes of 115 healthy subjects. The measurements were taken by the two optical biometers in random order. The measured parameters were axial length (AL), central corneal thickness (CCT), aqueous depth (AQD), anterior chamber depth (ACD), mean keratometry (Km), lens thickness (LT) and corneal diameter (CD). To evaluate the intraobserver repeatability and interobserver reproducibility, the within-subject SD, test-retest variability, coefficient of variation (CoV) and intraclass correlation coefficient (ICC) were adopted. The Bland-Altman plot was drawn to assess the agreement. RESULTS The repeatability and reproducibility of all parameters for the new device were excellent (ICC>0.960 and CoV<0.71%). The Bland-Altman plots showed high agreement between the OLCR-based and SS-OCT-based devices for AL, CCT, AQD, ACD, Km and LT, with narrow 95% limit of agreements (LoAs) (-0.08 mm to 0.06 mm, -15.91 µm to -1.01 µm, -0.09 mm to 0.09 mm, -0.09 mm to 0.08 mm, -0.47 D to 0.35 D, -0.05 mm to 0.16 mm, respectively) and moderate agreement for CD (95% LoA: -0.67 mm to -0.01 mm). CONCLUSIONS The new Suoer SW-9000 μm Plus biometer showed excellent repeatability and reproducibility. All the parameters obtained by this biometer were similar to those measured by SS-OCT-based biometer.
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Affiliation(s)
- Jinjin Yu
- Eye Institute and Department of Ophthalmology, Institute for Medical and Engineering Innovation, Eye & ENT Hospital, NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Fudan University, Shanghai, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | - Guoli Zhao
- Eye Institute and Department of Ophthalmology, Institute for Medical and Engineering Innovation, Eye & ENT Hospital, NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Fudan University, Shanghai, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | - Chak Seng Lei
- Eye Institute and Department of Ophthalmology, Institute for Medical and Engineering Innovation, Eye & ENT Hospital, NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Fudan University, Shanghai, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | - Ting Wan
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Rui Ning
- Eye Institute and Department of Ophthalmology, Institute for Medical and Engineering Innovation, Eye & ENT Hospital, NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Fudan University, Shanghai, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | - Wenqian Xing
- Eye Institute and Department of Ophthalmology, Institute for Medical and Engineering Innovation, Eye & ENT Hospital, NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Fudan University, Shanghai, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | - Xindi Ma
- Eye Institute and Department of Ophthalmology, Institute for Medical and Engineering Innovation, Eye & ENT Hospital, NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Fudan University, Shanghai, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | - Hongxian Pan
- Eye Institute and Department of Ophthalmology, Institute for Medical and Engineering Innovation, Eye & ENT Hospital, NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Fudan University, Shanghai, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | | | | | - Xingtao Zhou
- Eye Institute and Department of Ophthalmology, Institute for Medical and Engineering Innovation, Eye & ENT Hospital, NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Fudan University, Shanghai, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
| | - Jinhai Huang
- Eye Institute and Department of Ophthalmology, Institute for Medical and Engineering Innovation, Eye & ENT Hospital, NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Fudan University, Shanghai, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
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Wang L, Shao X, Fu JL, Hu JJ, Zhou KJ, Li R, Yu AY. Repeatability and Agreement of 4 Biometers Measuring Corneal Astigmatism in Eyes With Irregular Corneal Astigmatism Component. Am J Ophthalmol 2024; 265:200-212. [PMID: 38719132 DOI: 10.1016/j.ajo.2024.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 05/01/2024] [Accepted: 05/01/2024] [Indexed: 06/04/2024]
Abstract
PURPOSE To investigate the repeatability and agreement of corneal astigmatism measurements in eyes with irregular corneal astigmatism component (ICAC) using four devices: IOLMaster 700 biometer, Lenstar 900 biometer, iTrace, and Pentacam. DESIGN Prospective cross-sectional reliability analysis. METHODS Sixty-four eyes (52 patients) with ICAC were examined three times using the four devices. The eye with ICAC in this study is defined as the cornea has a certain degree of irregular astigmatism (asymmetric and/or skewed bowtie pattern of corneal topography according to corneal topography classification), accompanied with total corneal higher-order aberrations in the 4 mm zone of 0.3 µm or greater. Corneal astigmatism was evaluated using three categories: anterior corneal astigmatism (ACA), posterior corneal astigmatism, and total corneal astigmatism (TCA). The repeatability was determined using the ∆Ast (arithmetic mean of vector differences among three repeated corneal astigmatism measurements). Bland-Altman plots and astigmatism vector analyses were employed to assess agreement. RESULTS The IOLMaster 700 (∆Ast = 0.27 ± 0.20 D) showcased higher repeatability in ACA measurements compared to iTrace (∆Ast = 0.37 ± 0.38 D, P = .040) and Pentacam (∆Ast = 0.50 ± 0.22 D, P < .001), and paralleled the performance of Lenstar 900 (∆Ast = 0.31 ± 0.26 D, P = .338). The Pentacam (∆Ast = 0.09 ± 0.07 D, P < .001) demonstrated superior repeatability in posterior corneal astigmatism, whereas the IOLMaster 700 (∆Ast = 0.33 ± 0.23 D, P < .001) excelled in TCA. The IOLMaster 700 exhibited good agreement with either Lenstar 900 or iTrace, characterized by narrow 95% limits of agreement and clinically acceptable vector differences. Conversely, vector differences between Pentacam and the other three devices in ACA and TCA measurements were clinically significant, exceeding 0.50 D (all P < .05). CONCLUSIONS In terms of repeatability of corneal astigmatism measurements in eyes with ICAC, the IOLMaster 700 and Lenstar 900 outperformed iTrace and Pentacam. While the IOLMaster 700 can be used interchangeably with either Lenstar 900 or iTrace, the Pentacam is not interchangeable with the other three devices.
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Affiliation(s)
- Lan Wang
- From the National Clinical Research Center for Ocular Diseases, Eye Hospital (L.W., X.S., J.L.F., J.J.H., K.J.Z., R.L., A.Y.Y.), Wenzhou Medical University, Wenzhou, China
| | - Xu Shao
- From the National Clinical Research Center for Ocular Diseases, Eye Hospital (L.W., X.S., J.L.F., J.J.H., K.J.Z., R.L., A.Y.Y.), Wenzhou Medical University, Wenzhou, China
| | - Jin-Ling Fu
- From the National Clinical Research Center for Ocular Diseases, Eye Hospital (L.W., X.S., J.L.F., J.J.H., K.J.Z., R.L., A.Y.Y.), Wenzhou Medical University, Wenzhou, China
| | - Jing-Jing Hu
- From the National Clinical Research Center for Ocular Diseases, Eye Hospital (L.W., X.S., J.L.F., J.J.H., K.J.Z., R.L., A.Y.Y.), Wenzhou Medical University, Wenzhou, China
| | - Kai-Jing Zhou
- From the National Clinical Research Center for Ocular Diseases, Eye Hospital (L.W., X.S., J.L.F., J.J.H., K.J.Z., R.L., A.Y.Y.), Wenzhou Medical University, Wenzhou, China
| | - Ran Li
- From the National Clinical Research Center for Ocular Diseases, Eye Hospital (L.W., X.S., J.L.F., J.J.H., K.J.Z., R.L., A.Y.Y.), Wenzhou Medical University, Wenzhou, China
| | - A-Yong Yu
- From the National Clinical Research Center for Ocular Diseases, Eye Hospital (L.W., X.S., J.L.F., J.J.H., K.J.Z., R.L., A.Y.Y.), Wenzhou Medical University, Wenzhou, China; National Engineering Research Center of Ophthalmology and Optometry, Eye Hospital (A.Y.Y.), Wenzhou Medical University, Wenzhou, China.
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Venkataraman AP, Domínguez-Vicent A, Selin P, Brautaset R, Montés-Micó R. Precision of a new SS-OCT biometer to measure anterior segment parameters and agreement with 3 instruments with different measurement principles. J Cataract Refract Surg 2024; 50:486-491. [PMID: 38085173 PMCID: PMC11045405 DOI: 10.1097/j.jcrs.0000000000001380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 11/20/2023] [Accepted: 12/05/2023] [Indexed: 04/24/2024]
Abstract
PURPOSE To evaluate the repeatability of a new swept source optical coherence tomography (SS-OCT)-based biometer to measure anterior segment parameters and to assess the agreement with 3 other imaging devices based on different measurement principles. SETTING Unit of Eye and Vision, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden. DESIGN Prospective, comparative case series. METHODS 3 consecutive measurements were obtained in unoperated eyes with the Eyestar900 (SS-OCT), Lenstar 900, MS-39, and Sirius. The following anterior segment parameters were evaluated: central corneal thickness (CCT), corneal diameter (CD), aqueous depth (AQD), and corneal power metrics. The repeatability limit (Rlim), coefficient of variation (CoV), and a repeated measures Bland-Altman analysis were performed. RESULTS 74 eyes of 74 participants were measured. The Rlims for CCT, CD, and AQD were lower than 10 μm, 0.3 mm, and 0.10 mm for all devices, respectively. The corresponding CoVs for these parameters never exceeded 1.2%. The Rlim for the corneal power metrics never exceeded 0.60 diopter (D) for any of the instruments. Lenstar showed the best agreement with the MS-39 to measure CCT, CD, and AQD (limit of agreement interval, LoA: 15.54 μm, 0.55 mm, and 0.16 mm, respectively). The mean difference for keratometry parameters was lower than 0.3 D for all device comparisons, and the LoA interval ranged between 0.52 D and 1.21 D. CONCLUSIONS The repeatability for measuring anterior segment parameters was good, and the agreement among all the instruments was good for CD and AQD measurements. However, for CCT and keratometer parameters, the instruments cannot be used interchangeably due to large LoA interval.
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Affiliation(s)
- Abinaya Priya Venkataraman
- From the Division of Eye and Vision, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden (Venkataraman, Domínguez-Vicent, Selin, Brautaset); Optics and Optometry and Vision Sciences Department, University of Valencia, Valencia, Spain (Montés-Micó)
| | - Alberto Domínguez-Vicent
- From the Division of Eye and Vision, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden (Venkataraman, Domínguez-Vicent, Selin, Brautaset); Optics and Optometry and Vision Sciences Department, University of Valencia, Valencia, Spain (Montés-Micó)
| | - Paulina Selin
- From the Division of Eye and Vision, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden (Venkataraman, Domínguez-Vicent, Selin, Brautaset); Optics and Optometry and Vision Sciences Department, University of Valencia, Valencia, Spain (Montés-Micó)
| | - Rune Brautaset
- From the Division of Eye and Vision, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden (Venkataraman, Domínguez-Vicent, Selin, Brautaset); Optics and Optometry and Vision Sciences Department, University of Valencia, Valencia, Spain (Montés-Micó)
| | - Robert Montés-Micó
- From the Division of Eye and Vision, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden (Venkataraman, Domínguez-Vicent, Selin, Brautaset); Optics and Optometry and Vision Sciences Department, University of Valencia, Valencia, Spain (Montés-Micó)
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Langenbucher A, Hoffmann P, Cayless A, Bolz M, Wendelstein J, Szentmáry N. Impact of uncertainties in biometric parameters on intraocular lens power formula predicted refraction using a Monte-Carlo simulation. Acta Ophthalmol 2024; 102:e285-e295. [PMID: 37350286 DOI: 10.1111/aos.15726] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 05/14/2023] [Accepted: 06/12/2023] [Indexed: 06/24/2023]
Abstract
PURPOSE The purpose of this study was to investigate the uncertainty in the formula predicted refractive outcome REFU after cataract surgery resulting from measurement uncertainties in modern optical biometers using literature data for within-subject standard deviation Sw. METHODS This Monte-Carlo simulation study used a large dataset containing 16 667 preoperative IOLMaster 700 biometric measurements. Based on literature Sw values, REFU was derived for both the Haigis and Castrop formulae using error propagation strategies. Using the Hoya Vivinex lens (IOL) as an example, REFU was calculated both with (WLT) and without (WoLT) consideration of IOL power labelling tolerances. RESULTS WoLT the median REFU was 0.10/0.12 dpt for the Haigis/Castrop formula, and WLT it was 0.13/0.15 dpt. WoLT REFU increased systematically for short eyes (or high power IOLs), and WLT this effect was even more pronounced because of increased labelling tolerances. WoLT the uncertainty in the measurement of the corneal front surface radius showed the largest contribution to REFU, especially in long eyes (and low power IOLs). WLT the IOL power uncertainty dominated in short eyes (or high power IOLs) and the uncertainty of the corneal front surface in long eyes (or low power IOLs). CONCLUSIONS Compared with published data on the formula prediction error of refractive outcome after cataract surgery, the uncertainty of biometric measures seems to contribute with ⅓ to ½ to the entire standard deviation. REFU systematically increases with IOL power and decreases with axial length.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology, Saarland University, Homburg, Germany
| | - Peter Hoffmann
- Augen- und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany
| | - Alan Cayless
- School of Physical Sciences, The Open University, Milton Keynes, UK
| | - Matthias Bolz
- Department of Ophthalmology, Johannes Kepler University Linz, Austria
| | - Jascha Wendelstein
- Department of Experimental Ophthalmology, Saarland University, Homburg, Germany
- Department of Ophthalmology, Johannes Kepler University Linz, Austria
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg, Germany
- Department of Ophthalmology, Semmelweis-University, Budapest, Hungary
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Wang H, Zhu LS, Pang CJ, Fan Q. Repeatability assessment of anterior segment measurements in myopic patients using an anterior segment OCT with placido corneal topography and agreement with a swept-source OCT. BMC Ophthalmol 2024; 24:182. [PMID: 38649848 PMCID: PMC11036772 DOI: 10.1186/s12886-024-03448-z] [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: 11/22/2023] [Accepted: 04/10/2024] [Indexed: 04/25/2024] Open
Abstract
BACKGROUND The precision of anterior segment biometric measurements in eyes has become increasingly important in refractive surgery. The purpose of this study is to assess the repeatability of the automatic measurements provided by a new spectral-domain optical coherence tomograph (SD-OCT)/Placido topographer (MS-39, CSO) and its agreement with a swept-source OCT (SS-OCT) biometer (CASIA SS-1000, Tomey) in patients with myopia. METHODS The right eye of 235 subjects was scanned 3 times with both devices. The evaluated parameters included central corneal radius of the steep meridian, central corneal radius of the flat meridian, mean central corneal radius, thinnest corneal thickness, central corneal thickness, anterior chamber depth, corneal volume and diameter. The intraobserver repeatability of the MS-39 measurements was calculated using intraclass correlation coefficient (ICC), within subject standard deviation, coefficient of repeatability, coefficient of variation and repeated-measures analysis of variance of the 3 repeated measurements. The agreement between the two devices was evaluated by 95% limits of agreement (LoA). RESULTS The majority of the parameters acquired from MS-39 showed high repeatability. The repeatability of corneal diameter was slightly lower than the other measurements, although the ICC remained high. Agreement with the CASIA SS-1000 was good, indicated by the Bland-Altman plots with narrow 95% LoA values for all parameters assessed. CONCLUSIONS The high repeatability of automatic measurements by the new device supports its clinical application in eyes with myopia, and the good agreement between the two devices indicates they could be used interchangeably for the parameters evaluated.
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Affiliation(s)
- Hao Wang
- Department of Refractive Surgery, Henan Provincial People's Hospital, Henan Eye Hospital, People's Hospital Affiliated to Zhengzhou University, People's Hospital Affiliated to Henan University, NO.7 Weiwu Road, 450003, Zhengzhou, China
| | - Li-Shuang Zhu
- Department of Blood Transfusion, Zhengzhou People's Hospital, NO.33 Huanghe Road, 450003, Zhengzhou, China
| | - Chen-Jiu Pang
- Department of Refractive Surgery, Henan Provincial People's Hospital, Henan Eye Hospital, People's Hospital Affiliated to Zhengzhou University, People's Hospital Affiliated to Henan University, NO.7 Weiwu Road, 450003, Zhengzhou, China.
| | - Qi Fan
- Department of Refractive Surgery, Henan Provincial People's Hospital, Henan Eye Hospital, People's Hospital Affiliated to Zhengzhou University, People's Hospital Affiliated to Henan University, NO.7 Weiwu Road, 450003, Zhengzhou, China
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Langenbucher A, Wendelstein J, Cayless A, Hoffmann P, Szentmáry N. Vector analysis of corneal astigmatism in cataractous eyes based on IOLMaster 700 biometry. PLoS One 2024; 19:e0300576. [PMID: 38640111 PMCID: PMC11029642 DOI: 10.1371/journal.pone.0300576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2023] [Accepted: 02/29/2024] [Indexed: 04/21/2024] Open
Abstract
PURPOSE The purpose of this study was to investigate the effect of the corneal back surface by comparing the keratometric astigmatism (K, derived from the corneal front surface) of a modern optical biometer against astigmatism of Total Keratometry (TK, derived from both corneal surfaces) in a large population with cataractous eyes. The results were then used to define linear prediction models to map K to TK. METHODS From a large dataset containing bilateral biometric measurements (IOLMaster 700) in 9736 patients prior to cataract surgery, the total corneal astigmatism was decomposed into vectors for K, corneal back surface (BS), and TK. A multivariate prediction model (MV), simplified model with separation of vector components (SM) and a constant model (CM) were defined to map K to TK vector components. RESULTS The K centroid (X/Y) showed some astigmatism with-the-rule (0.1981/-0.0211 dioptre (dpt)) whereas the TK centroid was located around zero (-0.0071/-0.0381 dpt against-the-rule) and the BS centroid showed systematic astigmatism against-the-rule (-0.2367/-0.0145 dpt). The respective TK-K centroid was located at -0.2052/-0.0302 dpt. The MV model showed the same performance (i.e. mean absolute residuum) as the SM did (0.1098 and 0.1099 dpt respectively) while the CM performed only slightly worse (0.1121 dpt mean absolute residuum). CONCLUSION In cases where tomographic data are unavailable statistical models could be used to consider the overall contribution of the back surface to the total corneal astigmatism. Since the performance of the CM is sufficiently close to that of MV and SM we recommend using the CM which can be directly considered e.g. as surgically induced astigmatism.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology, Saarland University, Homburg/Saar, Germany
| | - Jascha Wendelstein
- Department of Experimental Ophthalmology, Saarland University, Homburg/Saar, Germany
- Department of Ophthalmology, Johannes Kepler University Linz, Linz, Austria
| | - Alan Cayless
- School of Physical Sciences, The Open University, Milton Keynes, United Kingdom
| | - Peter Hoffmann
- Augen- und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg/Saar, Germany
- Department of Ophthalmology, Semmelweis-University, Budapest, Hungary
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Alió JL, José-Martínez M, Martínez-Abad A, Rodríguez AE, Versaci F, Hjortdal J, Murta JN, Plaza-Puche AB, Cantó-Cerdán M, Piñero DP. Clinical Evaluation of a New Spectral-Domain Optical Coherence Tomography-Based Biometer. Diagnostics (Basel) 2024; 14:560. [PMID: 38473032 DOI: 10.3390/diagnostics14050560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/28/2024] [Accepted: 03/04/2024] [Indexed: 03/14/2024] Open
Abstract
The VEMoS-AXL system is a new optical biometer based on spectral domain optical coherence tomography (SD-OCT) that has been tested in terms of intrasession repeatability and compared with a swept-source optical coherence tomography biometer (SS-OCT), which is recognized as the gold standard for the performance of an agreement analysis. A biometric analysis was performed three consecutive times in 120 healthy eyes of 120 patients aged between 18 and 40 years with the SD-OCT system, and afterwards, a single measurement was obtained with the SS-OCT system. Within-subject standard deviations were 0.004 mm, 4.394 µm, and 0.017 mm for axial length (AL), central corneal thickness (CCT), and anterior chamber depth (ACD) measures obtained with the SD-OCT biometer, respectively. The agreement between devices was good for AL (limits of agreement, LoA: -0.04 to 0.03 mm) and CCT (LoA: -4.36 to 14.38 µm), whereas differences between devices were clinically relevant for ACD (LoA: 0.03 to 0.21 mm). In conclusion, the VEMoS-AXL system provides consistent measures of anatomical parameters, being most of them interchangeable with those provided by the SS-OCT-based gold standard.
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Affiliation(s)
- Jorge L Alió
- Research and Development Department, Vissum Grupo Miranza, 03016 Alicante, Spain
- School of Medicine, Miguel Hernandez University, 03202 Alicante, Spain
| | - Marina José-Martínez
- Research and Development Department, Vissum Grupo Miranza, 03016 Alicante, Spain
| | | | | | | | - Jesper Hjortdal
- Department of Opthalmology, Aarhus University Hospital, 8000 Aarhus, Denmark
| | - Joaquim Neto Murta
- Department of Opthalmology, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Ana B Plaza-Puche
- Research and Development Department, Vissum Grupo Miranza, 03016 Alicante, Spain
| | - Mario Cantó-Cerdán
- Research and Development Department, Vissum Grupo Miranza, 03016 Alicante, Spain
| | - David P Piñero
- Department of Optics, Pharmacology and Anatomy, University of Alicante, 03690 Alicante, Spain
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Yu J, Lin X, Huang X, Xu Z, Ning R, Li K, Savini G, Schiano-Lomoriello D, Zhou X, Huang J. Evaluation of a new dynamic real-time visualization 25 kHz swept-source optical coherence tomography based biometer. EYE AND VISION (LONDON, ENGLAND) 2024; 11:9. [PMID: 38433240 PMCID: PMC10910812 DOI: 10.1186/s40662-024-00377-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Accepted: 02/10/2024] [Indexed: 03/05/2024]
Abstract
BACKGROUND To evaluate the intraobserver repeatability and interobserver reproducibility of a newly developed dynamic real-time visualization 25 kHz swept-source optical coherence tomography (SS-OCT) based biometer (ZW-30, TowardPi Medical Technology Ltd, China) and compare its agreement with another SS-OCT based biometer (IOLMaster 700, Carl Zeiss Meditec AG, Jena, Germany). METHODS Eighty-two healthy right eyes were enrolled in this prospective observational study. Measurements were repeated for three times using the ZW-30 and IOLMaster 700 in a random order. Obtained parameters included axial length (AL), central corneal thickness (CCT), aqueous depth (AQD), anterior chamber depth (ACD), lens thickness (LT), mean keratometry (Km), astigmatism magnitude (AST), vector J0, vector J45, and corneal diameter (CD). The within-subject standard deviation (Sw), test-retest (TRT) variability, coefficient of variation (CoV), and intraclass correlation coefficient (ICC) were adopted to assess the intraobserver repeatability and interobserver reproducibility. The double-angle plot was also used to display the distribution of AST. To estimate agreement, Bland-Altman plots were used. RESULTS For the intraobserver repeatability and interobserver reproducibility, the Sw, TRT and CoV for all parameters were low. Meanwhile, the ICC values were all close to 1.000, except for the J45 (ICC = 0.887 for the intraobserver repeatability). The double-angle plot showed that the distribution of AST measured by these two devices was similar. For agreement, the Bland-Altman plots showed narrow 95% limits of agreements (LoAs) for AL, CCT, AQD, ACD, LT, Km AST, J0, J45, and CD (- 0.02 mm to 0.02 mm, - 7.49 μm to 8.08 μm, - 0.07 mm to 0.04 mm, - 0.07 mm to 0.04 mm, - 0.07 mm to 0.08 mm, - 0.16 D to 0.30 D, - 0.30 D to 0.29 D, - 0.16 D to 0.16 D, - 0.23 D to 0.13 D, and - 0.39 mm to 0.10 mm, respectively). CONCLUSIONS The newly dynamic real-time visualization biometer exhibited excellent intraobserver repeatability and interobserver reproducibility. The two devices both based on the SS-OCT principle had similar ocular parameters measurement values and can be interchanged in clinical practice.
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Affiliation(s)
- Jinjin Yu
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, N No. 19 Baoqing Road, Xuhui District, Shanghai, 200031, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
- Ningbo No. 2 Hospital, Ningbo, Zhejiang, China
- NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Xuanqiao Lin
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Xiaomin Huang
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, N No. 19 Baoqing Road, Xuhui District, Shanghai, 200031, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Zhenyu Xu
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, N No. 19 Baoqing Road, Xuhui District, Shanghai, 200031, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Rui Ning
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, N No. 19 Baoqing Road, Xuhui District, Shanghai, 200031, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Kexin Li
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, N No. 19 Baoqing Road, Xuhui District, Shanghai, 200031, China
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China
- NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | | | | | - Xingtao Zhou
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, N No. 19 Baoqing Road, Xuhui District, Shanghai, 200031, China.
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China.
- NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China.
| | - Jinhai Huang
- Eye Institute and Department of Ophthalmology, Eye & ENT Hospital, Fudan University, N No. 19 Baoqing Road, Xuhui District, Shanghai, 200031, China.
- Shanghai Research Center of Ophthalmology and Optometry, Shanghai, China.
- NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China.
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Langenbucher A, Szentmáry N, Cayless A, Hoffmann P, Wendelstein J, Cooke D. Repeatability of biometric measures from the IOLMaster 700 in a cataractous population. PLoS One 2024; 19:e0297869. [PMID: 38330090 PMCID: PMC10852222 DOI: 10.1371/journal.pone.0297869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 01/05/2024] [Indexed: 02/10/2024] Open
Abstract
PURPOSE The purpose of this study was to investigate the repeatability of biometric measures and also to assess the interactions between the uncertainties in these measures for use in an error propagation model, using data from a large patient cohort. METHODS In this cross-sectional non-randomised study we evaluated a dataset containing 3379 IOLMaster 700 biometric measurements taken prior to cataract surgery. Only complete scans with at least 3 successful measurements for each eye performed on the same day were considered. The mean (Mean) and standard deviations (SD) for each sequence of measurements were derived and analysed. Correlations between the uncertainties were assessed using Spearman rank correlations. RESULTS In the dataset with 677 eyes matching the inclusion criteria, the within subject standard deviation and repeatability for all parameters match previously published data. The SD of the axial length (AL) increased with the Mean AL, but there was no noticeable dependency of the SD of any of the other parameters on their corresponding Mean value. The SDs of the parameters are not independent of one another, and in particular we observe correlations between those for AL, anterior chamber depth, aqueous depth, lens thickness and corneal thickness. CONCLUSIONS The SD change over Mean for AL measurement and the correlations between the uncertainties of several biometric parameters mean that a simple Gaussian error propagation model cannot be used to derive the effect of biometric uncertainties on the predicted intraocular lens power and refraction after cataract surgery.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology, Saarland University, Homburg/Saar, Germany
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg/Saar, Germany
- Department of Ophthalmology, Semmelweis-University, Budapest, Hungary
| | - Alan Cayless
- School of Physical Sciences, The Open University, Milton Keynes, United Kingdom
| | - Peter Hoffmann
- Augen- und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany
| | - Jascha Wendelstein
- Department of Experimental Ophthalmology, Saarland University, Homburg/Saar, Germany
- Department of Ophthalmology, Johannes Kepler University Linz, Linz, Austria
| | - David Cooke
- Great Lakes Eye Care, Saint Joseph, MI, United States of America
- Department of Neurology and Ophthalmology, Michigan State University, College of Osteopathic Medicine, East Lansing, MI, United States of America
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Wagner FM, Hoffmann P, Preußner PR. Accuracy comparison of tomography devices for ray tracing-based intraocular lens calculation. J Cataract Refract Surg 2024; 50:110-115. [PMID: 37748039 DOI: 10.1097/j.jcrs.0000000000001320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2022] [Accepted: 09/17/2023] [Indexed: 09/27/2023]
Abstract
PURPOSE To evaluate the interchangeability of different tomography devices used for ray tracing-based intraocular lens (IOL) calculation. SETTING Eye clinic, Castrop-Rauxel, Germany. DESIGN Retrospective analysis. METHOD Measurements from 3 Placido-Scheimpflug devices and 3 optical coherence tomography (OCT) devices were compared in 83 and 161 other eyes after cataract surgery, respectively. 2-dimensional matrices of anterior local corneal curvature and local corneal thickness are transferred to the ray-tracing software OKULIX. Calculations are performed with the same IOL in the same position of an eye with the same axial length. Differences in spherical equivalent (SE), astigmatism, and spherical aberration are evaluated. Furthermore, the influence of the size of the matrices (optical zone) on the accuracy is quantified. RESULTS For the Placido-Scheimpflug devices, the deviations from the average of three measurements taken for each eye in SE (mean ± SD) were 0.17 ± 0.24 diopters (D), -0.26 ± 0.29 D, and 0.08 ± 0.39 D ( P < .001, analysis of variance [ANOVA]), for the centroids of the astigmatic differences 0.04 D/173 degrees, 0.14 D/93 degrees, and 0.10 D/7 degrees, and for the median of the absolute values of the vector differences 0.31 D, 0.33 D, and 0.29 D. For OCT devices, the corresponding results were 0.01 ± 0.21 D, -0.03 ± 0.21 D, and 0.02 ± 0.20 D ( P = .005, ANOVA); 0.18 D/120 degrees, 0.07 D/70 degrees, and 0.22 D/4 degrees; and 0.26 D, 0.30 D, and 0.33 D. The accuracy of the calculated spherical aberrations allows for an individual selection of the best fitting IOL model in most cases. CONCLUSIONS The differences are small enough to make the devices interchangeable regarding astigmatism and spherical aberration. Although there are significant differences in SE between Scheimpflug and OCT devices, the differences between OCT devices are also small enough to make them interchangeable, but the differences between Placido-Scheimpflug devices are too large to make these devices interchangeable.
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Affiliation(s)
- Felix M Wagner
- From the Department of Ophthalmology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany (Wagner, Preußner); Augen- & Laserklinik Castrop Rauxel GmbH, Castrop-Rauxel, Germany (Hoffmann)
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12
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Georgiev S, Ruiss M, Dana-Fisus A, Leitgeb RA, Findl O. Comparison of corneal aberrations from anterior segment swept source OCT versus Placido-topography combined spectral domain OCT in cataract patients. EYE AND VISION (LONDON, ENGLAND) 2023; 10:30. [PMID: 37525287 PMCID: PMC10392018 DOI: 10.1186/s40662-023-00348-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Accepted: 06/01/2023] [Indexed: 08/02/2023]
Abstract
BACKGROUND To comprehensively evaluate the agreement of component corneal aberrations from the newly updated wavefront analysis software of a swept-source optical coherence tomographer (SS-OCT) and a referential Placido-topography combined OCT device in elderly cataract patients. METHODS Retrospective study including 103 eyes from 103 elderly patients scheduled for cataract surgery that were measured on the same day with a SS-OCT (Heidelberg Engineering, Germany) device and a Placido-topography combined OCT device (CSO, Italy). Anterior, total, and posterior corneal wavefront aberrations were evaluated for their mean differences and limits of agreement (LoA) via Bland-Altman plots. Vector analysis was additionally employed to compare corneal astigmatism measurements in dioptric vector space. RESULTS Mean differences of all corneal aberrometric parameters did not exceed 0.05 μm. Total corneal aberrations were not significantly different from 0 except for vertical coma (- 0.04 μm; P = 0.003), spherical aberration (- 0.01 μm, P < 0.001), and root mean square (RMS) higher-order aberration (HOA) (0.03 μm, P = 0.04). The 95% LoA for total corneal aberration parameters between both devices were - 0.46 to 0.42 μm for horizontal astigmatism, - 0.37 to 0.41 μm for oblique astigmatism, - 0.19 to 0.17 μm for oblique trefoil, - 0.33 to 0.25 μm for vertical coma, - 0.20 to 0.22 μm for horizontal coma, - 0.22 to 0.20 μm for horizontal trefoil, - 0.11 to 0.08 μm for spherical aberration, and - 0.22 to 0.28 μm for RMS HOA. Vector analysis revealed no statistically significant mean differences for anterior, total, and posterior corneal astigmatism in dioptric vector space. CONCLUSION In eyes undergoing cataract surgery with a regular elderly cornea, corneal wavefront analysis from the SS-OCT device showed functional equivalency to the reference device. Nevertheless, clinically relevant higher order aberration parameters should be interpreted with caution for surgical decision-making.
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Affiliation(s)
- Stefan Georgiev
- VIROS-Vienna Institute for Research in Ocular Surgery, A Karl Landsteiner Institute, Hanusch Hospital, Heinrich-Collin-Strasse 30, 1140, Vienna, Austria
- Center for Medical Physics and Biomedical Engineering, Vienna, Austria
| | - Manuel Ruiss
- VIROS-Vienna Institute for Research in Ocular Surgery, A Karl Landsteiner Institute, Hanusch Hospital, Heinrich-Collin-Strasse 30, 1140, Vienna, Austria
| | - Andreea Dana-Fisus
- VIROS-Vienna Institute for Research in Ocular Surgery, A Karl Landsteiner Institute, Hanusch Hospital, Heinrich-Collin-Strasse 30, 1140, Vienna, Austria
| | - Rainer A Leitgeb
- Center for Medical Physics and Biomedical Engineering, Vienna, Austria
| | - Oliver Findl
- VIROS-Vienna Institute for Research in Ocular Surgery, A Karl Landsteiner Institute, Hanusch Hospital, Heinrich-Collin-Strasse 30, 1140, Vienna, Austria.
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Gjerdrum B, Gundersen KG, Nilsen C, Gundersen M, Jensen P. Refractive Predictability and Biometry Agreement of a Combined Swept Source Optical Coherence and Reflectometry Biometer Compared to an Optical Low Coherence Reflectometry Biometer and an SS-OCT Biometer. Clin Ophthalmol 2023; 17:1439-1452. [PMID: 37251985 PMCID: PMC10216845 DOI: 10.2147/opth.s408685] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 05/03/2023] [Indexed: 05/31/2023] Open
Abstract
Purpose To evaluate the agreement of refractive predictability of a swept-source optical coherence tomography (SS-OCT) biometer, which uses segmental AL calculation, with another SS-OCT biometer, and an optical low coherence reflectometry (OLCR) biometer. The secondary objective was to describe the refractive outcomes, visual acuities, and the agreement of different preoperative biometric parameters. Patients and Methods The study was a retrospective one-arm study of refractive and visual outcomes after successful cataract surgery. Preoperative biometric data were collected with two different SS-OCT device (Argos, Alcon Laboratories and Anterion, Heidelberg Engineering) and an OLCR device (Lenstar 900, Haag-Streit). The Barrett Universal II formula was used to calculate IOL power for all three devices. Follow-up examination was 1-2 months after surgery. The main outcome measure, refractive prediction error (RPE), was calculated as the achieved postoperative refraction minus the predicted refraction for each device. Absolute error (AE) was calculated by reducing the mean error to zero. Results The study included 129 eyes of 129 patients. The mean RPE was 0.06, -0.14 and 0.17 D for the Argos, Anterion and Lenstar, respectively (p < 0.01). The Argos also had the lowest absolute RPE, while the Lenstar had the lowest median AE, but this was not statistically significant (p > 0.2). The percentages of eyes with RPE within ±0.5 was 76%, 71%, and 78% for the Argos, Anterion, and Lenstar, respectively. The percentages of eyes with AE within 0.5 D was 79%, 84%, and 82% for the Argos, Anterion and Lenstar, respectively. None of these percentages were statistically significantly different (p > 0.2). Conclusion All three biometers showed good refractive predictability with no statistically significant differences in AE or percentages of eyes within ± 0.5 D of RPE or AE. The lowest arithmetic RPE was found with the Argos biometer.
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Affiliation(s)
| | | | - Christian Nilsen
- Ifocus Eye Clinic, Stavanger, Norway
- Faculty of Health Sciences, Oslo Metropolitan University, Oslo, Norway
| | - Morten Gundersen
- Ifocus Eye Clinic, Stavanger, Norway
- Faculty of Health Sciences, Oslo Metropolitan University, Oslo, Norway
| | - Per Jensen
- Ifocus Eye Clinic, Stavanger, Norway
- Faculty of Health Sciences, Oslo Metropolitan University, Oslo, Norway
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Michael R, Wirkner K, Engel C, Loeffler M, Kirsten T, Rauscher FG. Feasibility and repeatability of ocular biometry measured with IOLMaster 700 in a large population-based study. Ophthalmic Physiol Opt 2023. [PMID: 37083081 DOI: 10.1111/opo.13148] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 04/04/2023] [Accepted: 04/05/2023] [Indexed: 04/22/2023]
Abstract
PURPOSE To evaluate the feasibility and repeatability of IOLMaster 700 biometry measurements in an adult population. Furthermore, to assess the value of the Quality Indicators (QIs) provided by the device. METHOD As part of the large population-based Leipzig Research Centre for Civilization Diseases (LIFE) Adult-Study, randomly selected participants from Leipzig, Germany were evaluated with the ZEISS IOLMaster 700. Age range was 26-85 years, with 53% of participants above 70 years of age. Axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT) and keratometry (K) were assessed in 1767 right eyes. Measurements were repeated twice and in a subset of 1331 eyes, three times. Measurement feasibility was evaluated for three levels; successful, with warnings and failed, using the inbuilt QIs. Repeatability was assessed as within-subject standard deviation (SD) and repeatability limits were calculated. RESULTS First measurement success rate for phakic eyes was over 99% for AL, CCT, ACD, over 98% for LT and over 97% for K. K had 16% eyes with warnings and the recommendation to repeat the measurement. Excluding the measurements with warnings resulted in a reduction of mean SD for AL from 48 to 4 μm and for mean K from 0.08 to 0.04 D. Repeatability for phakic eyes was 8 μm for AL, CCT, ACD and LT and 2.3 μm for CCT; 0.07 D and 0.12 D for mean K and delta K, respectively, for phakic cases without warnings (two measurements). CONCLUSIONS In our population-based sample, the IOLMaster 700 collected data for AL, CCT, ACD, LT and K from the vast majority of eyes. Considering the built-in QIs improved the measurement variability substantially. Repeatability measurements indicate that clinically meaningful changes can be detected reliably with this instrument.
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Affiliation(s)
- Ralph Michael
- Institute for Medical Informatics, Statistics, and Epidemiology (IMISE), Leipzig University, Leipzig, Germany
- Medical Informatics Center - Dept. of Medical Data Science, Leipzig University Medical Centre, Leipzig, Germany
| | - Kerstin Wirkner
- Institute for Medical Informatics, Statistics, and Epidemiology (IMISE), Leipzig University, Leipzig, Germany
- Leipzig Research Centre for Civilization Diseases (LIFE), Leipzig University, Leipzig, Germany
| | - Christoph Engel
- Institute for Medical Informatics, Statistics, and Epidemiology (IMISE), Leipzig University, Leipzig, Germany
- Leipzig Research Centre for Civilization Diseases (LIFE), Leipzig University, Leipzig, Germany
| | - Markus Loeffler
- Institute for Medical Informatics, Statistics, and Epidemiology (IMISE), Leipzig University, Leipzig, Germany
- Leipzig Research Centre for Civilization Diseases (LIFE), Leipzig University, Leipzig, Germany
| | - Toralf Kirsten
- Institute for Medical Informatics, Statistics, and Epidemiology (IMISE), Leipzig University, Leipzig, Germany
- Medical Informatics Center - Dept. of Medical Data Science, Leipzig University Medical Centre, Leipzig, Germany
- Leipzig Research Centre for Civilization Diseases (LIFE), Leipzig University, Leipzig, Germany
| | - Franziska G Rauscher
- Institute for Medical Informatics, Statistics, and Epidemiology (IMISE), Leipzig University, Leipzig, Germany
- Medical Informatics Center - Dept. of Medical Data Science, Leipzig University Medical Centre, Leipzig, Germany
- Leipzig Research Centre for Civilization Diseases (LIFE), Leipzig University, Leipzig, Germany
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Jin A, Han X, Zhang J, Qiu X, Zhang Y, Qu B, Tan X, Luo L. Agreement of Total Keratometry and Posterior Keratometry Among IOLMaster 700, CASIA2, and Pentacam. Transl Vis Sci Technol 2023; 12:13. [PMID: 36928129 PMCID: PMC10029765 DOI: 10.1167/tvst.12.3.13] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023] Open
Abstract
Purpose The purpose of this study was to compare total keratometry (TK) and posterior keratometry (PK) obtained by two swept-source optical biometers (IOLMaster 700 and CASIA2) and one Scheimpflug-based topography (Pentacam AXL). Methods The TK and PK in cataract surgery candidates obtained by IOLMaster 700, CASIA2, and Pentacam AXL were compared. Intraclass correlation coefficients (ICCs), limit of agreement, and Bland-Altman plots were used to assess the agreement. Results One hundred two patients with a mean age of 68.21 ± 8.70 years were included. There were significant differences among IOLMaster 700, CASIA2, and Pentacam AXL in the mean TK (TKm) (44.23 ± 1.59 diopters [D] vs. 43.25 ± 1.53 D vs. 43.94 ± 1.68 D; all P < 0.001), mean PK (PKm; -5.90 ± 0.24 D vs. -6.25 ± 0.25 D vs. -6.37 ± 0.26 D; all P < 0.001) and TK-J0 (-0.34 ± 0.65 D vs. -0.23 ± 0.53 D vs. -0.12 ± 0.62 D; all P < 0.001). We also observed significant differences in PK-J45 between IOLMaster 700 and Pentacam AXL as well as between CASIA2 and Pentacam AXL (both P < 0.001). There was a good agreement in TKm, TK-J0, TK-J45, and PK-J0 (ICC = 0.887, 0.880, 0.751, and 0.807, respectively), a moderate agreement in PK-J45 (ICC = 0.626), and a poor agreement in PKm (ICC = 0.498) among these 3 biometers. Conclusions TK, PK, and the corresponding astigmatism obtained by IOLMaster 700, CASIA2, and Pentacam AXL showed significant differences, and could not be used interchangeably. Translational Relevance Our study may help to guide preoperative keratometry measurement for intraocular lens (IOL) power calculation and astigmatism evaluation for patients with cataract.
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Affiliation(s)
- Aixia Jin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Xiaotong Han
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Jiaqing Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Xiaozhang Qiu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Yifan Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Bo Qu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Xuhua Tan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Lixia Luo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
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Repeatability of new optical biometer and agreement with 2 validated optical biometers, all based on SS-OCT. J Cataract Refract Surg 2023; 49:5-10. [PMID: 36026703 DOI: 10.1097/j.jcrs.0000000000001023] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 07/19/2022] [Indexed: 12/31/2022]
Abstract
PURPOSE To evaluate the repeatability of the measurements provided by a new optical biometer (EyeStar 900) based on swept-source optical coherence tomography (SS-OCT) and their agreement with the measurements given by 2 validated biometers based on the same technology, the IOLMaster 700 and Argos. SETTING IRCCS G.B. Bietti Foundation, Rome, Italy. DESIGN Prospective evaluation of diagnostic test. METHODS In a series of unoperated eyes, 3 consecutive scans were acquired with the EyeStar 900, and 1 with the IOLMaster 700 and the Argos. The following biometry parameters were analyzed: axial length (AL), keratometry (K), corneal astigmatism, central corneal thickness, corneal diameter (CD), anterior chamber depth (ACD), lens thickness (LT), and lens tilting. Repeatability was assessed using test-retest variability, the coefficient of variation (CoV), and the intraclass correlation coefficient (ICC); agreement was based on the 95% limits of agreement. RESULTS 56 eyes of 56 patients were analyzed. High repeatability was achieved for all measured parameters, as the CoV was <1% in most cases and ICC was >0.95 for all parameters. Good to high agreement was found among the measurements of the 3 optical biometers, although some statistically significant differences were detected between the EyeStar 900 and Argos (mean K, ACD, LT, and CD were higher with the Argos). The Argos measured a shorter AL in eyes >25 mm. CONCLUSIONS The new generation SS-OCT EyeStar 900 optical biometer produces highly repeatable measurements that are in good agreement with those provided by 2 previously validated instruments.
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Langenbucher A, Szentmáry N, Cayless A, Wendelstein J, Hoffmann P. Comparison of 2 modern swept-source optical biometers—IOLMaster 700 and Anterion. Graefes Arch Clin Exp Ophthalmol 2022; 261:999-1010. [PMID: 36307658 PMCID: PMC10049935 DOI: 10.1007/s00417-022-05870-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/01/2022] [Accepted: 10/11/2022] [Indexed: 11/27/2022] Open
Abstract
Abstract
Purpose
To compare biometric measures from 2 modern swept-source OCT biometers (IOLMaster700 (Z, Carl-Zeiss-Meditec) and Anterion (H, Heidelberg Engineering)) and evaluate the effect of measurement differences on the resulting lens power (IOLP).
Methods
Biometric measurements were made on a large study population with both instruments. We compared axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT) and corneal front and back surface curvature measurements. Corneal curvature was converted to power vectors and total power derived using the Gullstrand formula. A paraxial lens power calculation formula and a prediction for the IOL axial position according to the Castrop formula were used to estimate differences in IOLP targeting for emmetropia.
Results
There were no systematic differences between measurements of AL (− 0.0146 ± 0.0286 mm) and LT (0.0383 ± 0.0595 mm), whereas CCT yielded lower (7.8 ± 6.6 µm) and ACD higher (0.1200 ± 0.0531 mm) values with H. With H, CCT was lower for thicker corneas. The mean corneal front surface radius did not differ (− 0.4 ± 41.6 µm), but the corneal back surface yielded a steeper radius (− 397.0 ± 74.6 µm) with H, giving lower mean total power (− 0.3469 ± 0.2689 dpt). The astigmatic vector components in 0°/90° and 45°/135° were the same between both instruments for the front/back surface or total power.
Conclusion
The biometric measures used in standard formulae (AL, corneal front surface curvature/power) are consistent between instruments. However, modern formulae involving ACD, CCT or corneal back surface curvature may yield differences in IOLP, and therefore, formula constant optimisation customised to the biometer type is required.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology, Saarland University, Kirrberger Str 100 Bldg. 22, 66424, Homburg, Saar, Germany.
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg, Saar, Germany
- Department of Ophthalmology, Semmelweis-University, Mária u. 39, 1085, Budapest, Hungary
| | - Alan Cayless
- School of Physical Sciences, The Open University, Milton Keynes, UK
| | | | - Peter Hoffmann
- Augen- und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany
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Kim KY, Lee S, Jeon YJ, Min JS. Anterior segment characteristics in normal and keratoconus eyes evaluated with a new type of swept-source optical coherence tomography. PLoS One 2022; 17:e0274071. [PMID: 36048835 PMCID: PMC9436129 DOI: 10.1371/journal.pone.0274071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 08/21/2022] [Indexed: 12/04/2022] Open
Abstract
Purpose This study aimed to evaluate and compare the discriminating ability of corneal elevation maps generated using a swept-source optical coherence tomography (SS-OCT) (SS-OCT ANTERION, Heidelberg Engineering, Heidelberg, Germany), which was estimated with different reference surfaces, to distinguish normal corneas from those with keratoconus and keratoconus suspect. Methods A total of 126 eyes of patients, which comprised 43, 37, and 46 keratoconus, keratoconus suspects, and normal controls, respectively, were included in this study. The anterior and posterior elevations at the thinnest point under the best-fit sphere (BFS) and toric-ellipsoid (BFT), respectively, and other corneal parameters were measured using the SS-OCT. In addition, the receiver operating characteristic (ROC) curve analysis and cut-off value were calculated to evaluate the diagnostic ability of the corneal elevation values in differentiating keratoconus and keratoconus suspects from normal eyes. Results The mean total keratometric and corneal elevation values were significantly higher in the keratoconus group than in the other groups. Pachymetric parameters exhibited the lowest values for keratoconus. In addition, ROC curve analyses showed a high accuracy of the thinnest point anterior and posterior BFT for both keratoconus and keratoconus suspects and normal controls (area under the ROC were 0.969 and 0.961, respectively). Furthermore, the optimal cut-off point of the posterior elevation at the thinnest point under BFT was 16.44 μm (sensitivity and specificity of 86% and 98%, respectively) for differentiating keratoconus from normal and keratoconus suspect eyes. Conclusions The elevation map using the BFS and BFT references measured with the anterior segment SS-OCT is considered an effective indicator for keratoconus diagnosis. Therefore, the anterior segment SS-OCT can effectively differentiate keratoconus from suspected keratoconus and normal corneas by measuring parameters such as posterior and anterior elevations, pachymetry, and keratometry.
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Langenbucher A, Hoffmann P, Cayless A, Wendelstein J, Bolz M, Szentmáry N. Meridional ocular magnification after cataract surgery with toric and non-toric intraocular lenses. Graefes Arch Clin Exp Ophthalmol 2022; 260:3869-3882. [PMID: 35776171 PMCID: PMC9666340 DOI: 10.1007/s00417-022-05740-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 06/01/2022] [Accepted: 06/22/2022] [Indexed: 11/24/2022] Open
Abstract
Background Overall ocular magnification (OOM) and meridional ocular magnification (MOM) with consequent image distortions have been widely ignored in modern cataract surgery. The purpose of this study was to investigate OOM and MOM in a general situation with an astigmatic refracting surface. Methods From a large dataset containing biometric measurements (IOLMaster 700) of both eyes of 9734 patients prior to cataract surgery, the equivalent (PIOLeq) and cylindric power (PIOLcyl) were derived for the HofferQ, Haigis, and Castrop formulae for emmetropia. Based on the pseudophakic eye model, OOM and MOM were extracted using 4 × 4 matrix algebra for the corrected eye (with PIOLeq/PIOLcyl (scenario 1) or with PIOLeq and spectacle correction of the residual refractive cylinder (scenario 2) or with PIOLeq remaining the residual uncorrected refractive cylinder (blurry image) (scenario 3)). In each case, the relative image distortion of MOM/OOM was calculated in %. Results On average, PIOLeq/PIOLcyl was 20.73 ± 4.50 dpt/1.39 ± 1.09 dpt for HofferQ, 20.75 ± 4.23 dpt/1.29 ± 1.01 dpt for Haigis, and 20.63 ± 4.31 dpt/1.26 ± 0.98 dpt for Castrop formulae. Cylindric refraction for scenario 2 was 0.91 ± 0.70 dpt, 0.89 ± 0.69 dpt, and 0.89 ± 0.69 dpt, respectively. OOM/MOM (× 1000) was 16.56 ± 1.20/0.08 ± 0.07, 16.56 ± 1.20/0.18 ± 0.14, and 16.56 ± 1.20/0.08 ± 0.07 mm/mrad with HofferQ; 16.64 ± 1.16/0.07 ± 0.06, 16.64 ± 1.16/0.18 ± 0.14, and 16.64 ± 1.16/0.07 ± 0.06 mm/mrad with Haigis; and 16.72 ± 1.18/0.07 ± 0.05, 16.72 ± 1.18/0.18 ± 0.14, and 16.72 ± 1.18/0.07 ± 0.05 mm/mrad with Castrop formulae. Mean/95% quantile relative image distortion was 0.49/1.23%, 0.41/1.05%, and 0.40/0.98% for scenarios 1 and 3 and 1.09/2.71%, 1.07/2.66%, and 1.06/2.64% for scenario 2 with HofferQ, Haigis, and Castrop formulae. Conclusion Matrix representation of the pseudophakic eye allows for a simple and straightforward prediction of OOM and MOM of the pseudophakic eye after cataract surgery. OOM and MOM could be used for estimating monocular image distortions, or differences in overall or meridional magnifications between eyes.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology, Saarland University, Kirrberger Str 100 Bldg. 22, 66424, Homburg, Saar, Germany.
| | - Peter Hoffmann
- Augen- Und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany
| | - Alan Cayless
- School of Physical Sciences, The Open University, Milton Keynes, UK
| | - Jascha Wendelstein
- Department of Experimental Ophthalmology, Saarland University, Kirrberger Str 100 Bldg. 22, 66424, Homburg, Saar, Germany.,Department of Ophthalmology, Johannes Kepler University Linz, Linz, Austria
| | - Matthias Bolz
- Department of Ophthalmology, Johannes Kepler University Linz, Linz, Austria
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg, Saar, Germany.,Department of Ophthalmology, Semmelweis-University, Mária u. 39, 1085, Budapest, Hungary
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20
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Langenbucher A, Szentmáry N, Cayless A, Wendelstein J, Hoffmann P. Prediction of ocular magnification and aniseikonia after cataract surgery. Acta Ophthalmol 2022; 100:e1675-e1684. [PMID: 35648485 DOI: 10.1111/aos.15190] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 05/14/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND Ocular magnification and aniseikonia after cataract surgery has been widely ignored in modern cataract surgery. The purpose of this study was to analyse ocular magnification and inter-individual differences in a normal cataract population with a focus on monovision. METHODS From a large dataset containing biometric measurements (IOLMaster 700) of both eyes of 9734 patients prior to cataract surgery, eyes were indexed randomly as primary (P) and secondary (S). Intraocular lens power (IOLP) was derived for the HofferQ, Haigis and Castrop formulae for emmetropia for P and emmetropia or myopia (-0.5 to -2 dpt) for S to simulate monovision. Based on the pseudophakic eye model in addition to these formulae, ocular magnification was extracted using matrix algebra (refraction and translation matrices and a system matrix describing the optical property of the entire spectacle corrected or uncorrected eye). RESULTS With emmetropia for P and S the IOLP differences (S-P) showed a standard deviation of 0.162/0.156/0.157 dpt and ocular magnification differences yielded a standard deviation of 0.0414/0.0405/0.0408 mm/mrad for the HofferQ/Haigis/Castrop setting. Simulating monovision, the myopic eye (S) showed a systematically smaller mean absolute spectacle corrected ocular magnification than the emmetropic eye (-0.0351/-0.0340/-0.0336, respectively, relative magnification around 2%). If myopia in the S eye remains uncorrected, the reduction of ocular magnification is much smaller (around 0.2-0.3%). CONCLUSION Vergence formulae for IOLP calculation sometimes implicitly define a pseudophakic eye model which can be directly used to predict ocular magnification after cataract surgery. Despite a strong similarity of both eyes, ocular magnification does not fully match between eyes and the prediction of ocular magnification and aniseikonia might be relevant to avoid eikonic problems in the pseudophakic eye.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology Saarland University Homburg/Saar Germany
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research Saarland University Homburg/Saar Germany
- Department of Ophthalmology Semmelweis‐University Budapest Hungary
| | - Alan Cayless
- School of Physical Sciences The Open University Milton Keynes UK
| | - Jascha Wendelstein
- Department of Experimental Ophthalmology Saarland University Homburg/Saar Germany
- Department of Ophthalmology Johannes Kepler University Linz Linz Austria
| | - Peter Hoffmann
- Augen‐ und Laserklinik Castrop‐Rauxel Castrop‐Rauxel Germany
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21
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Langenbucher A, Szentmáry N, Cayless A, Weisensee J, Wendelstein J, Hoffmann P. Translation model for CW chord to angle Alpha derived from a Monte-Carlo simulation based on raytracing. PLoS One 2022; 17:e0267028. [PMID: 35576202 PMCID: PMC9109904 DOI: 10.1371/journal.pone.0267028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 03/31/2022] [Indexed: 11/18/2022] Open
Abstract
Background The Chang-Waring chord is provided by many ophthalmic instruments, but proper interpretation of this chord for use in centring refractive procedures at the cornea is not fully understood. The purpose of this study is to develop a strategy for translating the Chang-Waring chord (position of pupil centre relative to the Purkinje reflex PI) into angle Alpha using raytracing techniques. Methods The retrospective analysis was based on a large dataset of 8959 measurements of 8959 eyes from 1 clinical centre, using the Casia2 anterior segment tomographer. An optical model based on: corneal front and back surface radius Ra and Rp, asphericities Qa and Qp, corneal thickness CCT, anterior chamber depth ACD, and pupil centre position (X-Y position: PupX and PupY), was defined for each measurement. Using raytracing rays with an incident angle IX and IY the CW chord (CWX and CWY) was calculated. Using these data, a multivariable linear model was built up in terms of a Monte-Carlo simulation for a simple translation of incident ray angle to CW chord. Results Raytracing allows for calculation of the CW chord CWX/CWY from biometric measures and the incident ray angle IX/IY. In our dataset mean values of CWX = 0.32±0.30 mm and CWY = -0.10±0.26 mm were derived for a mean incident ray angle (angle Alpha) of IX = -5.02±1.77° and IY = 0.01±1.47°. The raytracing results could be modelled with a linear multivariable model, and the effect sizes for the prediction model for CWX are identified as Ra, Qa, Rp, CCT, ACD, PupX, PupY, IX, and for CWY they are Ra, Rp, PupY, and IY. Conclusion Today the CW chord can be directly measured with any biometer, topographer or tomographer. If biometric measures of Ra, Qa, Rp, CCT, ACD, PupX, PupY are available in addition to the CW chord components CWX and CWY, a prediction of angle Alpha is possible using a simple matrix operation.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology, Universität des Saarlandes, Homburg/Saar, Germany
- * E-mail:
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Universität des Saarlandes, Homburg/Saar, Germany
- Department of Ophthalmology, Semmelweis-University, Budapest, Hungary
| | - Alan Cayless
- School of Physical Sciences, The Open University, Milton Keynes, United Kingdom
| | - Johannes Weisensee
- Department of Experimental Ophthalmology, Universität des Saarlandes, Homburg/Saar, Germany
| | - Jascha Wendelstein
- Department of Experimental Ophthalmology, Universität des Saarlandes, Homburg/Saar, Germany
- Medical Faculty, Johannes Kepler University Linz, Linz, Austria
| | - Peter Hoffmann
- Augen- und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany
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22
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Langenbucher A, Szentmáry N, Cayless A, Gasazza M, Weisensee J, Hoffmann P, Wendelstein J. Surgically induced astigmatism after cataract surgery - a vector analysis. Curr Eye Res 2022; 47:1279-1287. [PMID: 35380484 DOI: 10.1080/02713683.2022.2052108] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Background: Surgically induced astigmatism (SIA) has been widely discussed in the literature as the change in corneal astigmatism resulting from corneal incision. The purpose of this study was to investigate the change in corneal refractive power preoperative to postoperative using a vector analysis of keratometry, total keratometry, and corneal back surface data from a modern optical biometerMethods: The analysis was based on a dataset of 122 eyes of 122 patients with preoperative and 1 month postoperative measurements performed with the IOLMaster 700 biometer from 1 clinical centre and a standardised surgical technique involving a corneal 2.5 mm 45°-incision made from the superior direction. Keratometry, total keratometry and corneal back surface data were processed in 3 vector components (spherical equivalent power SEQ and astigmatism considered in 0°/90° (C0°) and in 45°/135° (C45°) meridian), and the changes in corneal power vectors were analysed, comparing preoperative to postoperative values.Results: The mean corneal power of total keratometry reduced slightly after cataract surgery (-0.05 dpt), resulting mostly from a decrease in back surface power (-0.04 dpt). The astigmatism vector component C0° of total keratometry reduced by -0.28 dpt, mostly due to a decrease at the corneal front surface (-0.26 dpt). With the corneal incision at 12 o'clock position this flattening in the 90° meridian refers to a SIA of around ¼ dpt. The change in C0° and the C45° astigmatic vector components for both keratometry and total keratometry show a large variation ranging between 0.24 and 0.33 dpt (standard deviations), indicating a poor predictability of the change in astigmatism due to cataract surgery.Conclusion: Cataract surgery locally flattens the cornea in the incision meridian. This flattening shows a large individual variation and therefore a poor predictability. Our study indicates that SIA in modern cataract surgery with standardised corneal incision is in a range of 1/4 dpt.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology, Saarland University, Homburg/Saar, Germany
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg/Saar, Germany.,Department of Ophthalmology, Semmelweis-University, Mária u. 39, 1085 Budapest, Hungary
| | - Alan Cayless
- School of Physical Sciences, The Open University, Milton Keynes, United Kingdom
| | - Marina Gasazza
- Augen- und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany
| | - Johannes Weisensee
- Department of Experimental Ophthalmology, Saarland University, Homburg/Saar, Germany
| | - Peter Hoffmann
- Department of Ophthalmology, Johannes Kepler University Linz, Austria
| | - Jascha Wendelstein
- Department of Experimental Ophthalmology, Saarland University, Homburg/Saar, Germany.,Augen- und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany
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23
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Cheng SM, Zhang JS, Shao X, Wu ZT, Li TT, Wang P, Lin JH, Yu AY. Repeatability of a new swept-source optical coherence tomographer and agreement with other three optical biometers. Graefes Arch Clin Exp Ophthalmol 2022; 260:2271-2281. [PMID: 35171331 DOI: 10.1007/s00417-022-05579-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 01/09/2022] [Accepted: 01/23/2022] [Indexed: 12/18/2022] Open
Abstract
PURPOSE To investigate the repeatability of Anterion and compare the agreement of ocular biometric measurements and predicted intraocular lens (IOL) powers with other three optical biometers. METHODS Flat keratometry (Kf), steep keratometry (Ks), J0 and 45 vectors, central cornea thickness (CCT), anterior chamber depth (ACD), and axial length (AL) from the Anterion, IOLMaster 700, Lenstar LS 900, and OA-2000 were recorded. The IOL powers were calculated with the Hoffer Q, Holladay 1, SRK/T, and Haigis formulas. The repeatability was evaluated using the within-subject standard deviation (Sw), repeatability coefficient (RC), coefficient of variation (COV), and intraclass correlation coefficient (ICC). Inter-device agreement between the four biometers was assessed with the 95% limits of agreement. RESULTS In total, 101 right eyes of 101 participants were enrolled. The Anterion showed good repeatability for all the included biometric parameters with all the CoV ≤ 0.30% and ICC ≥ 0.930 except for J45 with moderate repeatability (ICC was 0.849). Good agreement was found among the four devices for Kf, Ks, J0, J45, ACD, and AL. Generally, wide 95% LoA was found for the predicted IOL powers with the four IOL calculation formulas between the four devices. CONCLUSIONS The Anterion showed good repeatability of biometric measurements for most parameters. Good agreement among the four optical biometers was achieved for all the parameters except for CCT and the predicted IOL power. The AL values exhibited the best repeatability with Anterion and the best agreement among the biometers in our study.
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Affiliation(s)
- Shi-Ming Cheng
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, 270 West Xueyuan Road, Wenzhou, Zhejiang, 325027, People's Republic of China.,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, People's Republic of China.,Ophthalmology Department, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei, People's Republic of China
| | - Jia-Sheng Zhang
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, 270 West Xueyuan Road, Wenzhou, Zhejiang, 325027, People's Republic of China.,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, People's Republic of China
| | - Xu Shao
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, 270 West Xueyuan Road, Wenzhou, Zhejiang, 325027, People's Republic of China.,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, People's Republic of China
| | - Ze-Tong Wu
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, 270 West Xueyuan Road, Wenzhou, Zhejiang, 325027, People's Republic of China.,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, People's Republic of China
| | - Tian-Tian Li
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, 270 West Xueyuan Road, Wenzhou, Zhejiang, 325027, People's Republic of China.,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, People's Republic of China
| | - Po Wang
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, 270 West Xueyuan Road, Wenzhou, Zhejiang, 325027, People's Republic of China.,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, People's Republic of China
| | - Jun-Hai Lin
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, 270 West Xueyuan Road, Wenzhou, Zhejiang, 325027, People's Republic of China.,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, People's Republic of China
| | - A-Yong Yu
- Eye Hospital and School of Ophthalmology and Optometry, Wenzhou Medical University, 270 West Xueyuan Road, Wenzhou, Zhejiang, 325027, People's Republic of China. .,National Clinical Research Center for Ocular Diseases, Wenzhou, Zhejiang, People's Republic of China.
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Auffarth GU, Naujokaitis T, Blöck L, Daghbashyan A, Meis J, Augustin VA, Khoramnia R, Yildirim TM. Development and Verification of an Adjustment Factor for Determining the Axial Length Using Optical Biometry in Silicone Oil-Filled Eyes. Diagnostics (Basel) 2022; 12:diagnostics12010163. [PMID: 35054331 PMCID: PMC8775324 DOI: 10.3390/diagnostics12010163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/08/2022] [Accepted: 01/10/2022] [Indexed: 11/16/2022] Open
Abstract
The aim of this prospective clinical study was to establish and verify an adaptation for axial length (AL) measurement in silicone oil (SO)-filled pseudophakic eyes with a Scheimpflug and partial coherence interferometry (PCI)-based biometer. The AL was measured with a Pentacam AXL (OCULUS Optikgeräte GmbH, Wetzler, Germany) and IOLMaster 700 (Carl Zeiss Meditec, Jena, Germany). The coefficients of variation (CoV) and the mean systematic difference (95% confidence interval (CI)) between the devices were calculated. After implementing a setting for measuring AL in tamponaded eyes with a Pentacam based on data of 29 eyes, another 12 eyes were examined for verification. The mean AL obtained with the Pentacam was 25.53 ± 1.94 mm (range: 21.70 to 30.76 mm), and with IOLMaster, 24.73 ± 1.97 mm (ranged 20.84 to 29.92 mm), resulting in a mean offset of 0.80 ± 0.08 mm (95% CI: 0.77, 0.83 mm), p < 0.001. The AL values of both devices showed a strong linear correlation (r = 0.999). Verification data confirmed good agreement, with a statistically and clinically non-significant mean difference of 0.02 ± 0.04 (95% CI: −0.01, 0.05) mm, p = 0.134. We implemented a specific adaptation for obtaining reliable AL values in SO-filled eyes with the Pentacam AXL.
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Affiliation(s)
- Gerd U. Auffarth
- International Vision Correction Research Centre, Department of Ophthalmology, University of Heidelberg, 69120 Heidelberg, Germany; (T.N.); (L.B.); (A.D.); (V.A.A.); (R.K.); (T.M.Y.)
- Correspondence: ; Tel.: +49-6221-56-6624
| | - Tadas Naujokaitis
- International Vision Correction Research Centre, Department of Ophthalmology, University of Heidelberg, 69120 Heidelberg, Germany; (T.N.); (L.B.); (A.D.); (V.A.A.); (R.K.); (T.M.Y.)
| | - Louise Blöck
- International Vision Correction Research Centre, Department of Ophthalmology, University of Heidelberg, 69120 Heidelberg, Germany; (T.N.); (L.B.); (A.D.); (V.A.A.); (R.K.); (T.M.Y.)
| | - Anna Daghbashyan
- International Vision Correction Research Centre, Department of Ophthalmology, University of Heidelberg, 69120 Heidelberg, Germany; (T.N.); (L.B.); (A.D.); (V.A.A.); (R.K.); (T.M.Y.)
| | - Jan Meis
- Institute of Medical Biometry, University of Heidelberg, 69120 Heidelberg, Germany;
| | - Victor A. Augustin
- International Vision Correction Research Centre, Department of Ophthalmology, University of Heidelberg, 69120 Heidelberg, Germany; (T.N.); (L.B.); (A.D.); (V.A.A.); (R.K.); (T.M.Y.)
| | - Ramin Khoramnia
- International Vision Correction Research Centre, Department of Ophthalmology, University of Heidelberg, 69120 Heidelberg, Germany; (T.N.); (L.B.); (A.D.); (V.A.A.); (R.K.); (T.M.Y.)
| | - Timur M. Yildirim
- International Vision Correction Research Centre, Department of Ophthalmology, University of Heidelberg, 69120 Heidelberg, Germany; (T.N.); (L.B.); (A.D.); (V.A.A.); (R.K.); (T.M.Y.)
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25
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Langenbucher A, Szentmáry N, Cayless A, Weisensee J, Wendelstein J, Hoffmann P. Prediction of CW chord as a measure for the eye's orientation axis after cataract surgery from preoperative IOLMaster 700 measurement data. Acta Ophthalmol 2021; 100:e1232-e1239. [PMID: 34850585 DOI: 10.1111/aos.15071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 09/28/2021] [Accepted: 11/19/2021] [Indexed: 11/27/2022]
Abstract
BACKGROUND The angles alpha and kappa are widely discussed for centring refractive procedures, but they cannot be determined with ophthalmic instruments. The purpose of this study is to investigate the Chang-Waring chord (position of the Purkinje reflex PI relative to the corneal centre) derived from an optical biometer before and after cataract surgery and to study the changes resulting from cataract surgery. METHODS The analysis was based on a large dataset of 1587 complete sets of preoperative and postoperative IOMaster 700 biometry measurements from two clinical centres, each containing: valid data for pupil and corneal centre position, the position of the Purkinje reflex PI originated from a coaxial fixation target, keratometry (K), axial length (AL), anterior chamber depth (ACD), lens thickness (LT), central corneal thickness CCT, and horizontal corneal diameter W2W. The Chang-Waring chord CW was derived from pupil centre and Purkinje reflex PI analysed preoperatively and postoperatively, and a multilinear regression model together with a feedforward neural network algorithm was set up to predict postoperative CW chord from preoperative CW chord, K and biometric distances of the eye. RESULTS The Y component of CW chord shows a slight shift in the inferior direction in both left and right eyes, before and after cataract surgery. The X component shows some shift in the temporal direction, which is more pronounced preoperatively and slightly reduced postoperatively but with a larger variation. The change in CW chord from preoperative to postoperative shows a slight shift in the superior and nasal directions. Our algorithms for prediction of postoperative CW chord using preoperative CW chord, keratometry and biometry as input data performed with a multilinear regression and a feedforward neural network approach were able to reduce the variance, but could not properly predict the postoperative CW chord X and Y components. CONCLUSION The CW chord as the position of the Purkinje reflex PI with respect to the pupil centre can be directly measured with any biometer, topographer or tomographer with a coaxial fixation light. The mean Y component does not differ between right and left eyes or preoperatively and postoperatively, but the mean temporal shift of the X component preoperatively is slightly reduced postoperatively, but with a larger scatter of the values.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology Saarland University Homburg/Saar Germany
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research Saarland University Homburg/Saar Germany
- Department of Ophthalmology Semmelweis‐University Budapest Hungary
| | - Alan Cayless
- School of Physical Sciences The Open University Milton Keynes UK
| | - Johannes Weisensee
- Department of Experimental Ophthalmology Saarland University Homburg/Saar Germany
| | - Jascha Wendelstein
- Department of Ophthalmology Johannes Kepler University Linz Linz Austria
| | - Peter Hoffmann
- Augen‐ und Laserklinik Castrop‐Rauxel Castrop‐Rauxel Germany
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Langenbucher A, Szentmáry N, Cayless A, Weisensee J, Wendelstein J, Hoffmann P. Prediction of corneal back surface power - Deep learning algorithm versus multivariate regression. Ophthalmic Physiol Opt 2021; 42:185-194. [PMID: 34726283 DOI: 10.1111/opo.12909] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 09/30/2021] [Accepted: 09/30/2021] [Indexed: 11/30/2022]
Abstract
BACKGROUND The corneal back surface is known to add some against the rule astigmatism, with implications in cataract surgery with toric lens implantation. This study aimed to set up and validate a deep learning algorithm to predict corneal back surface power from the corneal front surface power and biometric measures. METHODS This study was based on a large dataset of IOLMaster 700 measurements from two clinical centres. N = 19,553 measurements of 19,553 eyes with valid corneal front (CFSPM) and back surface power (CBSPM) data and other biometric measures. After a vector decomposition of CFSPM and CBSPM into equivalent power and projections of astigmatism to the 0°/90° and 45°/135° axes, a multi-output feedforward neural network was derived to predict vector components of CBSPM from CFSPM and other measurements. The predictions were compared with a multivariate linear regression model based on CFSPM components only. RESULTS After pre-conditioning, a network with two hidden layers each having 12 neurons was derived. The dataset was split into training (70%), validation (15%) and test (15%) subsets. The prediction error (predicted corneal back surface power CBSPP - CBSPM) of the network after training and crossvalidation showed no systematic offset, narrower distributions for CBSPP - CBSPM and no trend error of CBSPP - CBSPM vs. CBSPM for any of the vector components. The multivariate linear model also showed no systematic offset, but broader distributions of the prediction error components and a systematic trend of all vector components vs. CFSPM components. CONCLUSION The neural network approach based on CFSPM vector components and other biometric measures outperforms the multivariate linear model in predicting corneal back surface power vector components. Modern biometers can supply all parameters required for this algorithm, enabling reliable predictions for corneal back surface data where direct corneal back surface data are unavailable.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology, Saarland University, Homburg/Saar, Germany
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research, Saarland University, Homburg/Saar, Germany.,Department of Ophthalmology, Semmelweis-University, Budapest, Hungary
| | - Alan Cayless
- School of Physical Sciences, The Open University, Milton Keynes, UK
| | - Johannes Weisensee
- Department of Experimental Ophthalmology, Saarland University, Homburg/Saar, Germany
| | | | - Peter Hoffmann
- Augen- und Laserklinik Castrop-Rauxel, Castrop-Rauxel, Germany
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Langenbucher A, Cayless A, Szentmáry N, Weisensee J, Wendelstein J, Hoffmann P. Prediction of total corneal power from measured anterior corneal power on the IOLMaster 700 using a feedforward shallow neural network. Acta Ophthalmol 2021; 100:e1080-e1087. [PMID: 34664393 DOI: 10.1111/aos.15040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Accepted: 09/22/2021] [Indexed: 11/29/2022]
Abstract
BACKGROUND The corneal back surface is known to add some astigmatism against-the-rule, which has to be considered in cataract surgery with toric lens implantation. The purpose of this study was to set up a deep learning algorithm which predicts the total corneal power from keratometry and biometric measures. METHODS Based on a large data set of measurements with the IOLMaster 700 from two clinical centres, data from N = 21 108 eyes were included, each record containing valid data for keratometry K, total keratometry TK, axial length AL, central corneal thickness CCT, anterior chamber depth ACD, lens thickness LT and horizontal corneal diameter W2W from an individual eye. After a vector decomposition of K and TK into equivalent power (.EQ) and projections of astigmatism to the 0°/90° (.AST0° ) and 45°/135° (.AST45° ) axis, a multi-output feedforward shallow neural network was derived to predict TK from K, AL, CCT, ACD, LT, W2W and patient age. RESULTS After some trial and error, the neural network having a Levenberg-Marquardt training function and three hidden layers (10/8/5 neurons) performed best and showed a fast convergence. The data set was split into training data (70%), validation data (15%) and test data (15%). The prediction error (predicted corneal power CPpred minus TK) of the network trained with the training and cross-validated with test data showed systematically narrower distributions for CPEQ-TKEQ, CPAST0° -TKAST0° and CPAST45° -TKAST45° compared with KEQ-TKEQ, KAST0° -TKAST0° and KAST45° -TKAST45° . There was no systematic offset in the components between CPpred and TK. CONCLUSION Unlike any fixed correction term, which can compensate only for a static intercept of the astigmatic components TKEQ, TKAST0° and TKAST45° compared with KEQ, KAST0° and KAST45° , our trained neural network was able to reduce the variance in the prediction error significantly. This neural network could be used to account for the corneal back surface astigmatism for biometers where the corneal back surface measurement or total keratometry is not available.
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Affiliation(s)
- Achim Langenbucher
- Department of Experimental Ophthalmology Saarland University Homburg/Saar Germany
| | - Alan Cayless
- School of Physical Sciences The Open University Milton Keynes UK
| | - Nóra Szentmáry
- Dr. Rolf M. Schwiete Center for Limbal Stem Cell and Aniridia Research Saarland University Homburg/Saar Germany
- Department of Ophthalmology Semmelweis‐University Budapest Hungary
| | - Johannes Weisensee
- Department of Experimental Ophthalmology Saarland University Homburg/Saar Germany
| | - Jascha Wendelstein
- Department of Ophthalmology Johannes Kepler University Linz Linz Austria
| | - Peter Hoffmann
- Augen‐ und Laserklinik Castrop‐Rauxel Castrop‐Rauxel Germany
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