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Almorín-Fernández-Vigo I, Sánchez-Guillén I, Fernández-Vigo JI, Burgos-Blasco B, De-Pablo-Gómez-de-Liaño L, Fernández-Vigo JÁ, Macarro-Merino A. Normative Topographic Anterior and Posterior Corneal Astigmatism: Axis Distribution and Its Relations with Ocular and Biometric Parameters. J Clin Med 2023; 12:jcm12113664. [PMID: 37297859 DOI: 10.3390/jcm12113664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/16/2023] [Accepted: 05/23/2023] [Indexed: 06/12/2023] Open
Abstract
Corneal astigmatism correction is a key factor when planning refractive treatment for ametropies with intraocular lenses. We aim to obtain normative anterior and posterior corneal astigmatism (ACA and PCA, respectively) data in a local population and to describe their axis distribution and their association with other parameters. A total of 795 patients with no ocular diseases were evaluated with corneal tomography and optical biometry. Only data of the right eye were included. Mean ACA and PCA were 1.01 ± 0.79 and 0.34 ± 0.17 D, respectively. Vertical steep axis distribution was 73.5% for ACA and 93.3% for PCA. Axis orientation between ACA and PCA matched best for vertical orientation (especially 90° to 120°). Vertical ACA orientation frequency decreased with age, with a more positive sphere and less ACA. Vertical PCA orientation frequency increased with higher PCA. Eyes with vertical ACA orientation were younger and showed a greater white-to-white (WTW) measurement, anterior corneal elevations, ACA and PCA. Eyes with vertical PCA orientation were younger and showed greater anterior corneal elevations and PCA. Normative ACA and PCA data in a Spanish population were presented. Steep axis orientations presented differences with age, WTW, anterior corneal elevations and astigmatism.
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Affiliation(s)
| | - Inés Sánchez-Guillén
- Centro Internacional de Oftalmología Avanzada, 06010 Badajoz, Spain
- Department of Ophthalmology, Hospital Perpetuo Socorro, 06010 Badajoz, Spain
| | - José Ignacio Fernández-Vigo
- Centro Internacional de Oftalmología Avanzada, 28010 Madrid, Spain
- Department of Ophthalmology, Hospital Clínico San Carlos, 28040 Madrid, Spain
| | | | | | - José Ángel Fernández-Vigo
- Centro Internacional de Oftalmología Avanzada, 06010 Badajoz, Spain
- Centro Internacional de Oftalmología Avanzada, 28010 Madrid, Spain
- School of Medicine, Universidad de Extremadura, 06006 Badajoz, Spain
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Wallerstein A, Gauvin M, Bernstein A, Qi SR, Cohen M. Posterior Corneal Astigmatism Does Not Influence Manifest-Treated Topography-guided LASIK Outcomes. J Refract Surg 2022; 38:780-790. [PMID: 36476302 DOI: 10.3928/1081597x-20221108-01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE To investigate whether the magnitude of posterior corneal astigmatism (PCA) impacts refractive and visual outcomes of primary topography-guided laser in situ keratomileusis (LASIK) and to provide guidance on treating eyes with high PCA. METHODS Comparative retrospective analysis of 4,541 consecutive eyes treated with Contoura (Alcon Laboratories, Inc) on the manifest refractive astigmatism. Standard outcomes of the 1,514 eyes with the lowest PCA (first tercile; low PCA group) were compared to the 1,514 eyes with the highest PCA (last tercile; high PCA group). Pearson correlation coefficient was used to assess relationships between variables. RESULTS Preoperatively, 20.9% of eyes presented with PCA of 0.50 diopters (D) or greater. The mean PCA was 0.18 ± 0.07 D in eyes with low PCA, and 0.50 ± 0.11 D in eyes with high PCA. An equivalent number of eyes achieved a cumulative postoperative unilateral uncorrected distance visual acuity of 20/20 in both the low PCA and high PCA groups (95.3% vs 94.7%; P = .4489). The efficacy index of both low and high PCA eyes was identical (0.99 ± 0.06 vs 0.99 ± 0.08; P = .3192), as was the safety index (1.00 ± 0.02 vs 1.00 ± 0.03; P = .0110). The magnitude of preoperative PCA was weakly correlated with postoperative refractive astigmatism (R = 0.1323), but not with postoperative defocus equivalent (R = -0.0414) or spherical equivalent (R = -0.0128). CONCLUSIONS PCA does not negatively impact the outcomes of topography-guided LASIK targeting the manifest refraction, having identical accuracy, efficacy, and safety in eyes with both low and high PCA. There is no scientific basis to measure and consider PCA in topography-guided LASIK planning software or nomograms if the excimer laser treatment input targets the manifest refraction. [J Refract Surg. 2022;38(12):780-790.].
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Watanabe K. Evaluation of Refractive Accuracy of ORA and the Factors Impacting Residual Astigmatism in Patients Implanted with Trifocal IOLs During Cataract Surgery: A Retrospective Observational Study. Clin Ophthalmol 2022; 16:2491-2503. [PMID: 35974901 PMCID: PMC9375987 DOI: 10.2147/opth.s371555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 07/26/2022] [Indexed: 11/23/2022] Open
Abstract
Purpose Patients and Methods Results Conclusion
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Affiliation(s)
- Keizo Watanabe
- Minami Osaka Eye Clinic, Osaka, Japan
- Correspondence: Keizo Watanabe, Minami Osaka Eye Clinic, Osaka, Japan, Tel +81 072-453-1750, Email
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Maraghechi G, Ojaghi H, Amani F, Najafi A. A comparative study of Pentacam indices in various types and severities of refractive error in candidates for photorefractive keratectomy (PRK) surgery. J Med Life 2022; 15:810-818. [PMID: 35928358 PMCID: PMC9321500 DOI: 10.25122/jml-2021-0027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 12/13/2021] [Indexed: 11/12/2022] Open
Abstract
This study aimed to specify Pentacam indices in patients who suffered from different types of refractive error and underwent photorefractive keratectomy (PRK) surgery. It is a descriptive cross-sectional study carried out on 1125 patients (2215 eye samples) who underwent PRK surgery in the Noor Surgical Center of Ardabil, Iran, over a 5 year period (2014-2018). A particular checklist was provided to patients, which consisted of demographic data, pachymetry test, keratometry, refractive error, corneal-thickness indices, and corneal surface area indices. The data were analysed using the statistical analysis package of IBM® V25. The mean age of the participants in this study was 28.48±6.82 years, and the ratio of women to men was 66.4%. It was observed that the differences between angle, volume, the depth of the anterior chamber, IVA, and ISV were significant (P=0.00) when compared to each other in all types of refractive errors. High myopes had significantly higher Kmax front than low myopes (P=0.00). In astigmatism patients, the Kmax in front of the cornea in extreme type was significantly higher than in moderate (P=0.00) and high (P=0.01) types. High myopes had significantly lower Rmin than mild myopes (P=0.02), and extreme astigmatism had significantly lower Rmin than high (P=0.014) and moderate types (P=0.013). The data from this study revealed that in patients undergoing PRK surgery, some Pentacam indices could be related to some types of refractive error, and in some of these indices, there are statistically significant differences between different severities of refractive errors. Therefore, their preoperative evaluation is very important.
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Affiliation(s)
- Ghazal Maraghechi
- Department of Medical Education, School of Medicine, Ardabil Azad University, Ardabil, Iran
| | - Habib Ojaghi
- Department of Surgery, School of Medicine and Allied Medical Sciences, Ardabil University of Medical Sciences, Ardabil, Iran,Corresponding Author: Habib Ojaghi, Department of Surgery, School of Medicine and Allied Medical Sciences, Ardabil University of Medical Sciences, Ardabil, Iran. E-mail:
| | - Firouz Amani
- Department of Community Medicine, School of Medicine and Allied Medical Sciences, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Amin Najafi
- Department of Surgery, School of Medicine and Allied Medical Sciences, Ardabil University of Medical Sciences, Ardabil, Iran
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Kose B. Agreement between swept-source optical biometry and Scheimpflug-based topography measurements of posterior corneal curvature. J Cataract Refract Surg 2022; 48:185-189. [PMID: 34174042 DOI: 10.1097/j.jcrs.0000000000000731] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 06/14/2021] [Indexed: 11/25/2022]
Abstract
PURPOSE To evaluate agreement of posterior corneal curvature parameters between a swept-source optical coherence tomography-based biometer (IOLMaster 700) and Scheimpflug topography (Pentacam HR) in healthy, myopic eyes. SETTING Department of Ophthalmology, Osmangazi Aritmi Hospital, Bursa, Turkey. DESIGN Retrospective study. METHODS In this study, 59 eyes of 59 patients who applied as candidates for refractive surgery were included. Measurements of the posterior corneal curvature were performed using IOLMaster 700 and Pentacam HR. J0 and J45 vector components were calculated using astigmatic values. Posterior corneal keratometry (K) measurements at flat (K flat) and steep (K steep) axes and J0 and J45 values were compared between the 2 devices. The agreement between the devices was analyzed using the Bland-Altman method. Intraclass correlation coefficients and within-subject SD were calculated to assess the repeatability. RESULTS 59 eyes of 59 patients were included in this study. The IOLMaster 700 provided significantly flatter K flat and K steep values (P < .001, for both). Significant differences were found in J0 and J45 values (P = 0.13 and P < .001, respectively). The mean differences between K flat, K steep, and J0 and J45 values were 0.49 diopter (D), 0.53 D, 0.04 D, and -0.05 D, respectively. CONCLUSIONS The IOLMaster 700 and the Pentacam HR could not be used interchangeably to measure K flat, K steep, and J0 and J45 values of the posterior corneal curvature in healthy, myopic eyes. Both devices showed high repeatability for posterior corneal curvature measurement.
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Affiliation(s)
- Bulent Kose
- From the Department of Ophthalmology, Osmangazi Aritmi Hospital, Bursa, Turkey
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Motamed-Gorji N, Jafari A, Mohammadi SF, Ashrafi E, Aliyari R, Emamian MH, Hashemi H, Fotouhi A. Associated factors and distribution of posterior corneal astigmatism in a middle-aged population. Clin Exp Optom 2021; 105:806-812. [PMID: 34751109 DOI: 10.1080/08164622.2021.1992249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Abstract
CLINICAL RELEVANCE Posterior corneal astigmatism has an important role in diagnosis and treatment of astigmatism, but it is usually overlooked. BACKGROUND This cross-sectional study aimed to investigate the distribution of posterior corneal astigmatism (PCA) and its associated factors in a middle-aged population that participated in the Shahroud Eye Cohort Study (ShECS) phase II. METHODS Anterior corneal astigmatism (ACA) and PCA values were measured using rotating Scheimpflug System (Pentacam HR, Oculus). With-the-rule (WTR) astigmatism was considered when the steepest corneal meridian was aligned within 90° ± 30°, and against-the-rule (ATR) astigmatism when the steepest meridian was 0 ± 30°. All the remaining values were considered as oblique astigmatism. Logistic regression models were used for evaluating the association of PCA magnitudes with other factors. RESULTS The current study consisted of 3871 eyes with available Pentacam data. Mean age of participants was 55.4 ± 6.1 years and 1557 (40.2%) subjects were male. Means of ACA and PCA were 0.77 ± 0.67 and -0.24 ± 0.15 D, respectively. The majority of PCA consisted of WTR astigmatism (82.43%), while ACA mostly showed ATR astigmatism (55.46%). PCA > 0.3 D was associated with male sex (OR = 1.16, P-value = 0.028) and spherical equivalent (OR = 0.93, P-value = 0.011) in the adjusted model, while PCA > 0.5 dioptre was strongly associated with myopia (OR = 4.6, P-value < 0.001). CONCLUSION The most common forms of ACA and PCA in middle-aged Iranian adults were ATR and WTR, respectively. While the shape of posterior corneal surface remained mostly unchanged across ages of 45 to 69 years, ACA was associated with a decrease in ATR proportion. Moreover, the most significant factors associated with higher magnitudes of PCA were male sex and myopia.
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Affiliation(s)
- Nazgol Motamed-Gorji
- Translational Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Ali Jafari
- Translational Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Farzad Mohammadi
- Translational Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Elham Ashrafi
- Translational Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Roqayeh Aliyari
- Ophthalmic Epidemiology Research Center, Shahroud University of Medical Sciences, Shahroud, Iran
| | - Mohammad Hassan Emamian
- Ophthalmic Epidemiology Research Center, Shahroud University of Medical Sciences, Shahroud, Iran
| | - Hassan Hashemi
- Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran
| | - Akbar Fotouhi
- Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
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Maraghechi G, Ojaghi H, Amani F, Moghadam TZ. Pentacam Indices in Photorefractive Keratectomy Surgery. J Med Life 2021; 13:523-529. [PMID: 33456601 PMCID: PMC7803299 DOI: 10.25122/jml-2020-0057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Refractive eye surgeries are one of the most non-emergent ophthalmic surgeries due to the effect on the reduction of refractive errors, increasing visual acuity, enhancing the quality of vision, and indirectly increasing the quality of life of patients. The aim of this study was to determine Pentacam indices in the patients who underwent photorefractive keratectomy (PRK) during 2014-2018, as well as to show their correlation with the type of refractive error. This descriptive cross-sectional study was performed on 2215 eyes of 1125 patients undergoing PRK surgery. The patients’ checklist, including demographic information, refractive index, keratometry, pachymetry, corneal surface zone indices, and progressive corneal thickness indices, was provided. All data were analyzed using the IBM SPSS software, version 25. The findings showed that there was a significant association between posterior corneal astigmatism (PCA) and anterior corneal astigmatism (ACA) (p=0.00). The mean Kmax front was recorded as 44.844 ± 1.58 D, which was significantly correlated with the type of refractive errors (p=0.00). According to the findings, there was a significant relationship between anterior chamber indices and refractive error types and their severity (p=0.00). There was also a significant correlation between the surface zone and keratoconus indices (i.e., index of surface variance - ISV, index of vertical asymmetry - IVA, index of height asymmetry - IHA, and minimum radius of curvature - Rmin) with refractive errors (p=0.00). The findings showed that some of the Pentacam indices could be related to the types of refractive errors in patients undergoing PRK surgery. Therefore, their evaluation is of great importance in this regard.
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Affiliation(s)
| | - Habib Ojaghi
- Department of Surgery, School of Medicine and Allied Medical Sciences, Imam Reza Hospital,Ardabil University of Medical Sciences, Ardabil, Iran
| | - Firouz Amani
- School of Medicine and Allied Medical Sciences, Ardabil University of Medical Sciences, Ardabil, Iran
| | - Telma Zahirian Moghadam
- Social Determinants of Health Research Center, Ardabil University of Medical Sciences, Ardabil, Iran
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Evaluation of posterior and total corneal astigmatism with colour-LED topography. Eye (Lond) 2020; 35:2585-2593. [PMID: 33203976 DOI: 10.1038/s41433-020-01278-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 10/29/2020] [Accepted: 10/30/2020] [Indexed: 11/09/2022] Open
Abstract
PURPOSE To characterise the posterior and total corneal astigmatism using colour point-source light-emitting diodes (LED) topography. METHODS In a prospective case series 400 eyes from 400 patients were evaluated by colour-LED topography. Only eyes with normal topographies were considered. The following parameters were studied: magnitude and distribution of SimK and posterior corneal astigmatism, correlation between SimK and posterior corneal astigmatism, and differences in magnitude and axis between total and anterior corneal astigmatism. RESULTS The mean SimK corneal astigmatism was 1.21 ± 0.94 D. The mean posterior corneal astigmatism was 0.37 ± 0.24 D. Posterior astigmatism was vertically oriented in 68% of eyes. Twenty-two percent of eyes showed a posterior corneal astigmatism ≥ 0.50 D. The correlation coefficients between SimK and posterior corneal astigmatism were: r2 = 0.066; p = 0.371 in WTR eyes, r2 = 0.112; p = 0.173 in ATR eyes and r2 = -0.019; p = 0.879 in oblique eyes. A difference between SimK and total corneal astigmatism ≥ 0.50 D was found in 7% of eyes. A difference in axis between SimK and total corneal astigmatism ≥ 10° was found in 24% of eyes. CONCLUSIONS The percentage of eyes with posterior corneal astigmatism ≥ 0.50 D and the differences between anterior and total corneal astigmatism were higher than those previously reported in the literature. Therefore, this study supports the consideration of total corneal astigmatism magnitude and axis is mandatory for a precise surgical correction of astigmatism.
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Li X, Chen X, He S, Xu W. Effect of 1.8-mm steep-axis clear corneal incision on the posterior corneal astigmatism in candidates for toric IOL implantation. BMC Ophthalmol 2020; 20:187. [PMID: 32375757 PMCID: PMC7204242 DOI: 10.1186/s12886-020-01456-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Accepted: 04/27/2020] [Indexed: 12/03/2022] Open
Abstract
Background In the present study, we aimed to analyze the effects of cataract surgery using a 1.8-mm steep-axis clear corneal incision (CCI) on the posterior corneal surfaces based on the keratometry from the rotating Scheimpflug imaging device (Pentacam HR) in candidates for toric intraocular lens (IOL) implantation. Methods Preoperative and at least 1-month postoperative data measured by Pentacam HR were collected in patients for toric IOL implantation. Surgically induced astigmatism on the posterior cornea (P-SIA) was calculated based on the preoperative and postoperative keratometric data, and the related factors of P-SIA were analyzed. Results A total of 60 eyes from 56 patients were enrolled. The preoperative anterior, posterior and total corneal astigmatism was 1.58 ± 0.61 D,0.28 ± 0.22 D and 1.70 ± 0.52 D respectively. The postoperative anterior, posterior and total corneal astigmatism was 1.26 ± 0.68 D, 0.41 ± 0.26 D and 1.30 ± 0.51 D respectively. The astigmatism was significantly decreased on anterior surface (P<0.001, paired t-test) and increased on posterior surface (P<0.001, paired t-test). The mean of P-SIA calculated by Holladay–Cravy–Koch method was 0.34 ± 0.20 D, with 0.5 D or greater accounting for 26.7%. A statistically significant correlation was observed between the P-SIA and preoperative anterior corneal astigmatism (r = 0.29, P = 0.024), as well as preoperative posterior corneal astigmatism (r = 0.27, P = 0.038). Multivariate regression analysis showed the preoperative anterior and posterior corneal astigmatism had a significant effect on P-SIA (F = 7.344, P = 0.001). Conclusions In candidates for toric IOL implantation with a 1.8-mm steep-axis CCI, the incision caused a significant reduction of the anterior corneal astigmatism but an increase of the posterior corneal astigmatism. P-SIA could not be ignored, and it played a significant role in SIA, especially in cases with higher preoperative anterior or posterior corneal astigmatism.
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Affiliation(s)
- Xi Li
- Eye Center, the Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, 310000, Zhejiang, China.,Department of Ophthalmology, Shanxi Provincial Cancer Hospital, Affiliated Cancer Hospital of Shanxi Medical University, Taiyuan, China
| | - Xiang Chen
- Eye Center, the Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, 310000, Zhejiang, China
| | - Suhong He
- Eye Center, the Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, 310000, Zhejiang, China.,Department of Ophthalmology, Suichang Hospital of Traditional Chinese Medicine, Suichang, China
| | - Wen Xu
- Eye Center, the Second Affiliated Hospital of Zhejiang University, College of Medicine, Hangzhou, 310000, Zhejiang, China.
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Management of Cataract in Patients with Irregular Astigmatism with Regular Central Component by Phacoemulsification Combined with Toric Intraocular Lens Implantation. J Ophthalmol 2020; 2020:3520856. [PMID: 32411427 PMCID: PMC7210554 DOI: 10.1155/2020/3520856] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Accepted: 03/23/2020] [Indexed: 12/15/2022] Open
Abstract
Purpose To evaluate visual acuity (VA) and refractive status in patients with cataract and irregular astigmatism with a regular central component after phacoemulsification with implantation of a toric intraocular lens (IOL). Methods Patients with cataract associated with irregular astigmatism with a regular central component were enrolled. All patients underwent phacoemulsification and toric IOL implantation. Postoperative visual acuity, residual astigmatism, toric IOL rotation, higher-order aberration, and objective and subjective visual quality were measured 3 months after surgery. Results Twenty-three eyes were included in the study. The logMAR corrected and uncorrected distance visual acuity values were decreased at 3 months postoperatively (p < 0.005). The preoperative average corneal astigmatism and postoperative residual astigmatism were 1.15–6.97 D (1.99 ± 1.26 D) and 0–2.75 D (0.65 ± 0.57 D), respectively. The average IOL rotation was 3.17 ± 2.01°. Some objective indicators of visual quality, including the modulation transfer function (p < 0.05), Strehl ratio (p < 0.005), 100% VA (p < 0.005), 20% VA (p < 0.005), and 9% VA (p < 0.005), were significantly higher than the corresponding preoperative values. The objective scatter index (p < 0.005) was significantly lower than that before surgery. The postoperative VF-14 scale score was 83.99 ± 14.58. Conclusion Toric IOL implantation has a good corrective effect on certain specific types of corneal irregular astigmatism with cataract. This effect can be attributed to its ability to correct the regular component of irregular astigmatism. The indications for toric IOL implantation could be expanded to some extent, thereby bringing benefit to more patients.
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Multivariate Regression Analysis to Predict Postoperative Refractive Astigmatism in Cataract Surgery. J Ophthalmol 2020; 2020:9842803. [PMID: 32411437 PMCID: PMC7201842 DOI: 10.1155/2020/9842803] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 12/26/2019] [Indexed: 11/24/2022] Open
Abstract
Purpose To assess the correlation between postoperative refractive astigmatism and preoperative parameters in cataract surgery. Methods Left eyes of 100 consecutive patients scheduled for cataract surgery with a 2.4 mm clear corneal incision were examined prospectively. Refractive astigmatism was measured using an autokerato/refractometer. Corneal astigmatism of the total cornea was calculated using a Scheimpflug camera. The vertical/horizontal component (J0) and oblique component (J45) of refractive and total corneal astigmatism were determined using power vector analysis. Refractive astigmatism at 8 weeks postoperatively was estimated using multivariate linear regression analysis. Independent variables analyzed included age, sex, refractive astigmatism, total corneal astigmatism, sphere, intraocular pressure, corneal thickness, anterior chamber depth, lens thickness, axial length, and pupil diameter. Results Multivariate regression analysis identified total corneal J0 and age as significant contributors to postoperative refractive J0 (P < 0.001 and P=0.029, respectively). The standard partial regression coefficients in the multiple regression analysis were 0.59 and −0.16 for total corneal J0 and age, respectively. Significant contributors to postoperative refractive J45 were total corneal J45 and lens thickness (P < 0.001 and P=0.015, respectively). The standard partial regression coefficients were 0.79 and −0.15 for total corneal J45 and lens thickness, respectively. Conclusion These results suggest that preoperative total corneal astigmatism is the most significant predictor of postoperative refractive astigmatism when performing astigmatism correction in cataract surgery.
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Lu W, Miao Y, Li Y, Hu X, Hu Q, Huang J. Comparison of Multicolored Spot Reflection Topographer and Scheimpflug-Placido System in Corneal Power and Astigmatism Measurements With Normal and Post-refractive Patients. J Refract Surg 2019; 35:370-376. [PMID: 31185102 DOI: 10.3928/1081597x-20190510-01] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 05/09/2019] [Indexed: 11/20/2022]
Abstract
PURPOSE To evaluate the repeatability of corneal power and astigmatism derived by a novel multicolored spot reflection topographer system (Cassini; i-Optics, Hague, Netherlands) and compare its agreement with a Placido-Scheimpflug system (Sirius; Costruzione Strumenti Oftalmici, Florence, Italy) in normal and post-refractive patients. METHODS This prospective study comprised patients who underwent myopic excimer laser refractive surgery (96 eyes) and normal patients (102 eyes). Each patient was measured three times with the Cassini and Sirius. The simulated keratometry (SimK), total corneal power (TCP), and astigmatism were recorded. The repeatability was assessed by one-way analysis of variance. The paired t test was used to compare the differences, whereas the agreement was evaluated by Bland-Altman analysis. RESULTS All parameters obtained by the Cassini demonstrated high repeatability, except for total corneal astigmatism (TCA) in the post-refractive group. The intraclass correlation coefficients of all parameters were greater than 0.85, the correlation of variation values was less than 0.55%, and the test-retest repeatability was less than 0.85 diopters (D). The paired t test showed significant differences in steep keratometry, astigmatism, TCP, and TCA in the normal group and in J0, TCP, and TCA in the post-refractive group. The 95% limits of agreement (LoA) in the normal group demonstrated good agreement, except for TCP. Only J0 and J45 of astigmatism and TCA remained narrow for 95% LoA in the post-refractive group. CONCLUSIONS These results suggested that the Cassini provided high repeatable measurements in corneal power and astigmatism, except the TCA of post-refractive patients. The parameters could be used interchangeably in normal patients, except for TCP, whereas only J0 of astigmatism and J0, J45 of TCA showed good agreement in post-refractive patients. [J Refract Surg. 2019;35(6):370-376.].
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Mohammadi SF, Khorrami-Nejad M, Hamidirad M. Posterior corneal astigmatism: a review article. CLINICAL OPTOMETRY 2019; 11:85-96. [PMID: 31496856 PMCID: PMC6697663 DOI: 10.2147/opto.s210721] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 07/29/2019] [Indexed: 05/15/2023]
Abstract
Most human eyes show at least a small degree of corneal astigmatism and it can arise from both surfaces of the cornea. The shape of the anterior corneal surface provides no definitive basis for knowing the toricity of the posterior surface. In the previous studies, average astigmatism of the posterior corneal surface was -0.26 to -0.78 diopter. The radius of the posterior corneal surface is less than the radius of the anterior corneal surface. Most studies have found a clear correlation between the anterior and posterior corneal asphericities and the asphericity of the posterior surface is independent of the vertex radius of curvature, refractive error and gender. In contrast to the anterior corneal surface, the asphericity of the posterior corneal surface varies significantly between meridians. The anterior and posterior corneal surface would have approximately parallel principal meridians and both of these surfaces are often flatter in the horizontal meridian than the vertical one. This is especially true in the higher degrees of corneal astigmatism, and then about 10% of any anterior corneal astigmatism is neutralized by an astigmatism arising from the posterior corneal surface. Although the second corneal surface only contributes to about 10% of the total refractive power of the eye, a precise knowledge of its morphology is needed for the correct diagnosis and monitoring the corneal diseases or the surgical interventions and in many eyes neglecting the posterior corneal surface measurement may lead to significant deviations from the corneal astigmatism estimation. In this article, we have reviewed the shape and the toricity of the posterior corneal surface and also the effect of age on it. We investigated the contribution of posterior corneal astigmatism to the total corneal astigmatism and evaluated the accuracy of corneal astigmatism estimation by neglecting the posterior corneal surface measurement.
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Affiliation(s)
- Seyed-Farzad Mohammadi
- Translational Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences
, Tehran, Iran
| | - Masoud Khorrami-Nejad
- Translational Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences
, Tehran, Iran
- School of Rehabilitation, Shahid Beheshti University of Medical Sciences
, Tehran, Iran
| | - Moein Hamidirad
- School of Rehabilitation, Shahid Beheshti University of Medical Sciences
, Tehran, Iran
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Li C, Zhang J, Yin X, Li J, Cao Y, Lu P. Distribution and related factors of corneal regularity and posterior corneal astigmatism in cataract patients. Clin Ophthalmol 2019; 13:1341-1352. [PMID: 31440022 PMCID: PMC6664321 DOI: 10.2147/opth.s212946] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2019] [Accepted: 06/23/2019] [Indexed: 11/24/2022] Open
Abstract
Purpose To study the distribution of posterior corneal astigmatism (PCA) and its influencing factors in Chinese patients before cataract surgery. Patients and methods A retrospective study was conducted in the First Affiliated Hospital of Soochow University, Suzhou, China. In all, this study enrolled 121 eligible eyes of 121 cataract patients. The astigmatism, aberrations and Q value of anterior, posterior and total cornea and anterior segment parameters (ACD, CCT, WTW, ATA) were measured by the Sirius System, and AL was measured by Lenstar LS 900. Cataract was diagnosed using slit-lamp examination. Results The mean age of patients was 67.44±10.66 years old. Mean PCA was 0.31±0.17 (range 0.05–1.09) D and 85.9% eyes had PCA values <0.5 D. With-the-rule (WTR) astigmatism predominated the anterior cornea astigmatism (ACA) (48.8%) and total corneal astigmatism (TCA) (61.2%), while against-the-rule (ATR) astigmatism predominated posterior (86.0%). Significant positive correlation was found between the astigmatic power vector (APV) of ACA and PCA (Pearson correlation=0.318, P<0.001); TCA and PCA (Pearson correlation=0.204, P=0.025); keratometric astigmatism and PCA (Pearson correlation=0.356, P<0.001); this study also found a positive correlation between primary spherical aberration (Z4°) of the total cornea and PCA (Pearson correlation=0.266, P=0.003); primary spherical aberration (Z4°) of the corneal front surface and PCA (Pearson correlation=0.260, P=0.004); total corneal aberrations (Total cornea root mean square [RMS]) and PCA (Pearson correlation=0.327, P<0.001); total corneal higher-order
aberrations (Total HOA RMS) (Pearson correlation=0.232, P=0.011); total corneal lower-order aberrations (Total LOA RMS) (Pearson correlation=0.250, P=0.006). A positive linear correlation between Q value of corneal front surface and PCA, either 6 mm pupil diameter (Pearson correlation=0.264, P=0.003) or 8 mm pupil diameter (Pearson correlation=0.184, P=0.043) was found in this study. Conclusion Corneal aberration, Q value (front surface specifically) was essential that we need to take into consideration when we conduct PCA and intraocular
lens measurement in clinics.
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Affiliation(s)
- Chen Li
- Department of Ophthalmology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
| | - Jiaju Zhang
- Department of Ophthalmology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
| | - Xue Yin
- Department of Ophthalmology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
| | - Jianqing Li
- Department of Ophthalmology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
| | - Yihong Cao
- Department of Ophthalmology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
| | - Peirong Lu
- Department of Ophthalmology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
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García-García Á, Melián R, Carreras H, Rodríguez-Hernández V, Reñones J, Estévez B. Corneal dioptric power and astigmatism: A comparison between colour light-emitting diode based (Cassini TM) and Scheimpgflug technology (Pentacam TM) topography. ARCHIVOS DE LA SOCIEDAD ESPANOLA DE OFTALMOLOGIA 2019; 94:273-280. [PMID: 30878244 DOI: 10.1016/j.oftal.2018.11.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 11/24/2018] [Accepted: 11/29/2018] [Indexed: 12/11/2022]
Abstract
AIM To determine the agreement and to compare the measurements obtained from a colour light-emitting diode based (CassiniTM) and Scheimpflug (PentacamTM) based topography in the evaluation of the anterior, posterior, and total corneal power and astigmatism. METHODS A total of 30 eyes from 30 healthy patients were consecutively measured using PentacamTM and CassiniTM. The main evaluated parameters were the anterior, posterior, and total dioptric power, and a power vector analysis of the astigmatism. The agreement between both devices was analysed using the intraclass correlation coefficient (ICC) and performing Bland-Altman plots. The comparison of means was performed using paired Student t-test. RESULTS The agreement between both devices when comparing the anterior and total corneal dioptric power was very high (ICC>0.85), but not when studying the posterior cornea (ICC<0.5). In the astigmatism analysis, measurements from the anterior cornea also showed an excellent agreement (ICC>0.78), but was poor for the corneal posterior surface (ICC<0.31). When studying the corneal dioptric power, no statistically significant differences were found for the anterior surface (P>.05), but PentacamTM obtained higher values for posterior and total surfaces (P<.001). As regards the magnitude of the astigmatism, no significant differences were found between both devices. CONCLUSION Both devices were highly comparable when studying the anterior cornea, but the agreement was poor-moderate when measuring posterior cornea. Therefore, the data obtained by both topographers are not interchangeable.
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Affiliation(s)
- Á García-García
- Clínica Eurocanarias Ofalmológica, Las Palmas de Gran Canaria, Las Palmas, España.
| | - R Melián
- Clínica Eurocanarias Ofalmológica, Las Palmas de Gran Canaria, Las Palmas, España
| | - H Carreras
- Clínica Eurocanarias Ofalmológica, Las Palmas de Gran Canaria, Las Palmas, España
| | | | - J Reñones
- Clínica Eurocanarias Ofalmológica, Las Palmas de Gran Canaria, Las Palmas, España
| | - B Estévez
- Clínica Eurocanarias Ofalmológica, Las Palmas de Gran Canaria, Las Palmas, España
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Effects of aging on corneal parameters measured with Pentacam in healthy subjects. Sci Rep 2019; 9:3419. [PMID: 30833606 PMCID: PMC6399218 DOI: 10.1038/s41598-019-39234-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 01/17/2019] [Indexed: 11/08/2022] Open
Abstract
Our purpose was to prospectively analyze the age-related changes of corneal Scheimpflug parameters in healthy subjects. Thirty-five eyes of 35 volunteers (age 14-67 years) were investigated with an average interval of 3.6 years. Changes of corneal parameters (flattest keratometric reading at anterior (K1F) and posterior surface (K1B), steepest keratometric reading at anterior (K2F) and posterior surface, anterior astigmatism, posterior astigmatism (AstigB), flat axis of anterior and posterior astigmatism (AxisB), thinnest pachymetric value (PachyMin), corneal volume (CV10-mm)) were analyzed. K1F and K2F decreased significantly during observation and showed stronger decrease in younger than in older individuals. Higher values proved to be more stable. K1B decreased significantly and the degree of decrease was dependent on its baseline value and age: in young subjects low values increased, high values decreased. AstigB decreased significantly and showed a baseline-dependent significant increase from lower and a significant decrease from higher initial values. Over time, the mean AxisB shifted significantly. PachyMin and CV decreased significantly with age, especially from higher baseline values in younger subjects. The results of this longitudinal study suggest that both corneal surfaces change significantly with age. We demonstrate for the first time that age and baseline values influence age-related changes of corneal parameters.
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Núñez MX, Henriquez MA, Escaf LJ, Ventura BV, Srur M, Newball L, Espaillat A, Centurion VA. Consensus on the management of astigmatism in cataract surgery. Clin Ophthalmol 2019; 13:311-324. [PMID: 30809088 PMCID: PMC6376888 DOI: 10.2147/opth.s178277] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
This project was aimed at achieving consensus on the management of astigmatism during cataract surgery by ophthalmologists from Latin America using modified Delphi technique. Relevant peer-reviewed literature was identified, and 21 clinical research questions associated with the definition, classification, measurement, and treatment of astigmatism during cataract surgery were formulated. Twenty participants were divided into seven groups, and each group was assigned three questions to which they had to respond in written form, after thoroughly reviewing the literature. The assigned questions with corresponding responses by each group were discussed with other participants in round 4 – presentation of findings. The consensus was achieved if approval was obtained from at least 80% of participants. The present paper provides several agreements and recommendations for management of astigmatism during cataract surgery, which could potentially minimize the variability in practice patterns and help ophthalmologists adopt optimal practices for cataract patients with astigmatism and improve patient satisfaction.
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Affiliation(s)
- Maria X Núñez
- Unit of Cornea, Cataract and Refractive Surgery, Grupo de Investigacion Vision Sana, Clinica de Oftalmología de Cali, Universidad Javeriana, Cali, Colombia,
| | - Maria A Henriquez
- Department of Cataract, Department of Research, Oftalmosalud Instituto de Ojos, Lima, Peru
| | - Luis J Escaf
- Clinica Oftalmologica del Caribe (Cofca), Universidad Javeriana, Barranquilla, Colombia
| | - Bruna V Ventura
- Department of Cataract, Altino Ventura Foundation, HOPE Eye Hospital, Recife, Brazil
| | - Miguel Srur
- Centro de la Visión, Filial Clínica Las Condes, Universidad de Los Andes, Santiago de Chile, Chile
| | | | - Arnaldo Espaillat
- Cataract and refractive surgery service, Espaillat Cabral Institute, Santo Domingo, Dominican Republic
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Kim H, An Y, Joo CK. Gender-differences in age-related changes of corneal astigmatism in Korean cataract patients. BMC Ophthalmol 2019; 19:31. [PMID: 30678644 PMCID: PMC6346567 DOI: 10.1186/s12886-018-1001-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2018] [Accepted: 12/06/2018] [Indexed: 11/23/2022] Open
Abstract
Background This cross-sectional study investigated age-related changes in anterior, posterior, and total corneal astigmatism and evaluated sex differences in corneal astigmatism with increasing age in cataract patients. Methods This study evaluated eyes with cataracts from May 2009 and July 2013. All eyes underwent a complete ophthalmological examination and corneal Scheimpflug imaging by a Pentacam camera (Oculus, Wetzlar, Germany). Anterior, posterior, and total corneal astigmatism were determined. Power vector J0 and linear regression analyses were determined and compared with respect to age and sex. Results Four hundred and fifteen patients (217 men, 198 women) aged 20–89 years were evaluated. For anterior corneal astigmatism, 100% of patients who were 20–39 years old had with-the-rule (WTR) in both sexes. WTR was significantly lower in patients 80–89 years old (25.6% of men and 37.8% of women). For total corneal astigmatism, WTR also tended to decrease with increasing age: 93.3% of men and 100% of women 20–39 years old versus 20.9% of men and 31.1% of women 80–89 years old. The regression coefficient of both the anterior corneal and total corneal J0 vector values analyzed by age were − 0.018 in men and − 0.016 in women (both p < .001). Conclusions The against-the-rule shift was faster for total corneal astigmatism than for anterior corneal astigmatism and it occurred earlier in men than in women. Trial registration Retrospectively registered. Registration number: KC15RISI0241. Registered April 20, 2016.
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Affiliation(s)
- Hyojin Kim
- Department of Visual Optics, Division of Health Science and Graduate School of Health and Welfare, Baekseok University, Cheonan, South Korea
| | - Youngju An
- Catholic Institute for Visual Science, College of Medicine, The Catholic University of Korea, Seoul, South Korea
| | - Choun-Ki Joo
- Catholic Institute for Visual Science, College of Medicine, The Catholic University of Korea, Seoul, South Korea. .,Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, #505 Banpo-Dong, Seocho-Gu, Seoul, 137-040, South Korea.
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Hayashi K, Sato T, Yoshida M, Yoshimura K. Corneal shape changes of the total and posterior cornea after temporal versus nasal clear corneal incision cataract surgery. Br J Ophthalmol 2018; 103:181-185. [PMID: 29777048 PMCID: PMC6362889 DOI: 10.1136/bjophthalmol-2017-311710] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 04/03/2018] [Indexed: 11/07/2022]
Abstract
Aim To compare changes in the shape and astigmatism of the total and posterior cornea between eyes with a nasal clear corneal incision (CCI) and eyes with a temporal CCI in cataract surgery. Methods The left eyes of 100 patients undergoing phacoemulsification were randomly assigned to undergo a 2.4 mm nasal (nasal CCI group) or temporal CCI (temporal CCI group). Corneal astigmatic changes were compared between groups using power vector analysis, and corneal shape changes were compared using videokeratography maps at 2 days, and at 2, 4 and 8 weeks postoperatively. Results The mean J0 and J45 values of the total cornea were significantly greater in the nasal CCI group than in the temporal CCI group at 2 and 4 weeks postoperatively (p≤0.0392), but did not differ significantly between groups at 2 days and 8 weeks. The videokeratography maps revealed a wedge-shaped flattening in the total cornea and a steepening in the posterior cornea around the CCIs in both groups at 2 days postoperatively; those were more prominent in the nasal CCI group than in the temporal CCI group. The wound-related changes diminished by 8 weeks postoperatively in the total and posterior cornea, and were not markedly different between groups at 8 weeks postoperatively. Conclusion Corneal shape and astigmatic changes were comparable between groups at 8 weeks postoperatively, although the changes were greater after nasal CCI than after temporal CCI in the early postoperative periods, indicating that nasal or temporal CCI can be selected based on the surgeon’s preference.
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McNeely RN, Moutari S, Pazo E, Moore JE. Investigating the impact of preoperative corneal astigmatism orientation on the postoperative spherical equivalent refraction following intraocular lens implantation. EYE AND VISION 2018; 5:7. [PMID: 29736407 PMCID: PMC5926537 DOI: 10.1186/s40662-018-0103-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Accepted: 04/10/2018] [Indexed: 11/10/2022]
Abstract
Background To investigate the impact of the orientation of preoperative corneal astigmatism on achieving the postoperative target refraction following monofocal intraocular lens (IOL) implantation. Methods This study enrolled 339 eyes who had uneventful cataract surgery or refractive lens exchange (RLE) with subsequent monofocal IOL implantation. Eyes were initially categorized dependent upon axial length and then on the orientation of preoperative anterior corneal astigmatism. Group 1 had against-the-rule (ATR) anterior corneal astigmatism, group 2 had with-the-rule (WTR) anterior corneal astigmatism, and group 3 had oblique (OB) anterior corneal astigmatism. The preoperative corneal astigmatism was determined by the IOLMaster (Carl Zeiss Meditec AG). Postoperative refraction was completed for all eyes, and the results were calculated and compared for the separate groups. Results In eyes with axial lengths greater than 22.0 mm and less than 25.0 mm there was a significant difference between the magnitude of preoperative corneal astigmatism between groups 2 and 3 with 0.827 ± 0.376 D in group 2, and 0.677 ± 0.387 D in group 3. The mean postoperative spherical equivalent (SE) prediction error was - 0.132 ± 0.475 D in group 1, 0.026 ± 0.497 D in group 2, and - 0.130 ± 0.477 D in group 3. There was a significant difference between groups 1 and 2. There was no significant difference in the magnitude of preoperative corneal astigmatism and postoperative SE prediction error between the anterior corneal astigmatism orientation groups in eyes with axial lengths of less than or equal to 22.0 mm and greater than or equal to 25.0 mm. Conclusions The orientation of preoperative anterior corneal astigmatism significantly affected the postoperative biometry prediction error in eyes with astigmatism of 1.75 D or less in eyes with the axial length between 22.0 mm and 25.0 mm. However, the results were not clinically significant.
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Affiliation(s)
- Richard N McNeely
- Cathedral Eye Clinic, 89-91 Academy Street, Belfast, County Antrim BT1 2 LS Northern Ireland, UK.,2Biomedical Sciences Research Institute, University of Ulster, Coleraine, Northern Ireland, UK
| | - Salissou Moutari
- 3School of Mathematics and Physics, Queens University Belfast, Belfast, Northern Ireland, UK
| | - Eric Pazo
- Cathedral Eye Clinic, 89-91 Academy Street, Belfast, County Antrim BT1 2 LS Northern Ireland, UK.,2Biomedical Sciences Research Institute, University of Ulster, Coleraine, Northern Ireland, UK
| | - Jonathan E Moore
- Cathedral Eye Clinic, 89-91 Academy Street, Belfast, County Antrim BT1 2 LS Northern Ireland, UK.,2Biomedical Sciences Research Institute, University of Ulster, Coleraine, Northern Ireland, UK
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Feizi S, Delfazayebaher S, Javadi MA, Karimian F, Ownagh V, Sadeghpour F. Mean Posterior Corneal Power and Astigmatism in Normal Versus Keratoconic Eyes. J Ophthalmic Vis Res 2018; 13:93-100. [PMID: 29719635 PMCID: PMC5905325 DOI: 10.4103/jovr.jovr_19_17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Purpose: To compare mean posterior corneal power and astigmatism in normal versus keratoconus affected eyes and determine the optimal cut-off points to maximize sensitivity and specificity in discriminating keratoconus from normal corneas. Methods: A total of 204 normal eyes and 142 keratoconus affected eyes were enrolled in this prospective comparative study. Mean posterior corneal power and astigmatism were measured using a dual Scheimpflug camera. Correlation coefficients were calculated to assess the relationship between the magnitudes of keratometric and posterior corneal astigmatism in the study groups. Receiver operating characteristic curves were used to compare the sensitivity and specificity of the measured parameters and to identify the optimal cut-off points for discriminating keratoconus from normal corneas. Results: The mean posterior corneal power was −6.29 ± 0.20 D in the normal group and −7.77 ± 0.87 D in the keratoconus group (P < 0.001). The mean magnitudes of the posterior corneal astigmatisms were −0.32 ± 0.15 D and −0.94 ± 0.39 D in the normal and keratoconus groups, respectively (P < 0.001). Significant correlations were found between the magnitudes of keratometric and posterior corneal astigmatism in the normal (r=−0.76, P < 0.001) and keratoconus (r=−0.72, P < 0.001) groups. The mean posterior corneal power and astigmatism were highly reliable characteristics that distinguished keratoconus from normal corneas (area under the curve, 0.99 and 0.95, respectively). The optimal cut-off points of mean posterior corneal power and astigmatism were −6.70 D and −0.54 D, respectively. Conclusion: Mean posterior corneal power and astigmatism measured using a Galilei analyzer camera might have potential in diagnosing keratoconus. The cut-off points provided can be used for keratoconus screening.
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Affiliation(s)
- Sepehr Feizi
- Ocular Tissue Engineering Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Siamak Delfazayebaher
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Ali Javadi
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Farid Karimian
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Vahid Ownagh
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fatemeh Sadeghpour
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Hayashi K, Yoshida M, Hirata A, Yoshimura K. Changes in shape and astigmatism of total, anterior, and posterior cornea after long versus short clear corneal incision cataract surgery. J Cataract Refract Surg 2018; 44:39-49. [DOI: 10.1016/j.jcrs.2017.10.037] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 08/30/2017] [Accepted: 10/02/2017] [Indexed: 11/29/2022]
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Kim YJ, Knorz MC, Auffarth GU, Choi CY. Change in Anterior and Posterior Curvature After Cataract Surgery. J Refract Surg 2017; 32:754-759. [PMID: 27824379 DOI: 10.3928/1081597x-20160816-01] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 08/08/2016] [Indexed: 11/20/2022]
Abstract
PURPOSE To analyze the change in anterior and posterior corneal curvature after cataract surgery using a Placido-dual rotating Scheimpflug device. METHODS In a prospective cross-sectional study, corneal curvature was measured using the Galilei G4 device (Ziemer Ophthalmic Systems, Port, Switzerland) preoperatively and 1 week and 1, 3, and 6 months after cataract surgery with a temporal limbal self-sealing 2.2-mm incision. The surgically induced astigmatism (SIA) was determined on the anterior and posterior surfaces. RESULTS Fifty-nine patients (68 eyes) were assessed. Based on the anterior corneal surface, 16 (23.5%) eyes had a vertically steep meridian (with-the-rule [WTR] astigmatism), 32 (47.1%) had a horizontally steep meridian (against-the-rule [ATR] astigmatism), and 20 (29.4%) had oblique astigmatism. Based on the posterior corneal surface, 2 (2.9%) eyes had a horizontally steep meridian (ATR astigmatism), 62 (91.2%) had a vertically steep meridian (WTR astigmatism), and 4 (5.9%) had oblique astigmatism. SIA of the anterior and posterior corneal surfaces was 0.61 ± 0.33 and 0.20 ± 0.17 diopters (D), respectively. However, there was no significant difference between the preoperative and the 6-month postoperative data in the Jackson coefficient orthogonal coordinate system for the anterior and posterior corneal surfaces. SIA of WTR astigmatism of the posterior cornea was 0.19 ± 0.16 D at 6 months. Sixty-one of 62 eyes with WTR astigmatism in the posterior corneal surface still showed WTR astigmatism after cataract surgery. CONCLUSIONS The tendency of SIA of the posterior cornea may not be uniform, but type of posterior corneal astigmatism did not change in most cases after the 2.2-mm temporal limbal incision cataract surgery. [J Refract Surg. 2016;32(11):754-759.].
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Changes in Anterior, Posterior, and Total Corneal Astigmatism after Descemet Membrane Endothelial Keratoplasty. J Ophthalmol 2017; 2017:4068963. [PMID: 28553547 PMCID: PMC5434235 DOI: 10.1155/2017/4068963] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 03/25/2017] [Accepted: 03/27/2017] [Indexed: 11/17/2022] Open
Abstract
Purpose. To evaluate changes in anterior, posterior, and total corneal astigmatism in patients after Descemet membrane endothelial keratoplasty (DMEK). Methods. We retrospectively included 29 eyes of 23 patients (age 67.6 ± 9.8 years, 13 female, 10 male) after DMEK surgery. The magnitude and axis orientation of anterior, posterior, and total corneal astigmatism before and after DMEK were determined using a rotating Scheimpflug system (Pentacam HR, Oculus). Results. The magnitude of anterior, posterior, and total corneal astigmatism in the central cornea did not change significantly after surgery. Before surgery, we found a significant correlation between the magnitudes of anterior and posterior corneal astigmatism (Spearman's correlation coefficient (rS) = 0.526, P = 0.003), while after surgery this correlation was no longer significant (rS = 0.038, P = 0.843). There was a significant correlation between the vector difference between preoperative and postoperative posterior astigmatism and the change in corneal pachymetry (rP = 0.47, P = 0.010). Conclusions. Posterior corneal astigmatism (especially the orientation) and therefore the relationship between anterior and total corneal astigmatism may change after DMEK. This should be considered to improve the accuracy of toric IOL power calculations following phakic DMEK or in combined procedures.
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de Sanctis U, Donna P, Penna RR, Calastri MI, Eandi CM. Corneal Astigmatism Measurement by Ray Tracing Versus Anterior Surface-Based Keratometry in Candidates for Toric Intraocular Lens Implantation. Am J Ophthalmol 2017; 177:1-8. [PMID: 28185842 DOI: 10.1016/j.ajo.2017.01.031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 01/26/2017] [Accepted: 01/28/2017] [Indexed: 10/20/2022]
Abstract
PURPOSE To compare corneal astigmatism derived from total corneal refractive power (CATCRP), a ray-tracing method, with that derived from simulated keratometry (CASimK), an anterior surface-based method, in candidates for toric intraocular lens (IOL) implantation. DESIGN Reliability analysis. METHODS In 1 eye of 200 consecutive patients (mean age 71 ± 9 years) with cataract, a Pentacam HR (Oculus) was used to measure CATCRP and CASimK. Eyes with CATCRP >1 diopter (D) were defined as candidates for toric IOL implantation. The estimation difference between CATCRP and CASimK was analyzed by calculating the arithmetic, absolute, and vector differences between the 2 methods. RESULTS Seventy-seven candidates were identified. In the candidates, CASimK was <1 D in 22% of cases and underestimated the astigmatism magnitude, on average, by -0.15 ± 0.34 D. The mean absolute and vector difference between CATCRP and CASimK was 0.31 ± 0.29 D and 0.30 ± 0.29 D × 180 degrees, respectively. The absolute and vector differences between the 2 methods were >0.50 D in 21 of 77 (27.2%) and 25 of 77 (32.5%) eyes, respectively; the proportions were significantly (P < .001) higher than in the eyes with CATCRP ≤1 D (0.8% and 9.8%, respectively). The difference in steep meridian alignment between CATCRP and CASimK was >5 degrees in 22.1% and >10 degrees in 2.6% of cases. CONCLUSION The difference between CATCRP and CASimK, as calculated by Pentacam HR, is greater in candidates for toric IOL implantation than in the general population. That difference considerably influences the candidate and toric IOL power selection in a large proportion of cases.
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Calculations of actual corneal astigmatism using total corneal refractive power before and after myopic keratorefractive surgery. PLoS One 2017; 12:e0175268. [PMID: 28403194 PMCID: PMC5389789 DOI: 10.1371/journal.pone.0175268] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Accepted: 03/23/2017] [Indexed: 11/27/2022] Open
Abstract
Purpose To calculate actual corneal astigmatism using the total corneal refractive astigmatism for the 4-mm apex zone of the Pentacam (TCRP4astig) and keratometric astigmatism (Kastig) before and after photorefractive keratectomy or laser in situ keratomileusis Methods Uncomplicated 56 eyes after more than 6 months from the surgery were recruited by chart review. Various corneal astigmatisms were measured using the Pentacam and autokeratometer before and after surgery. Three eyes were excluded and 53 eyes of 38 subjects with with-the-rule astigmatism (WTR) were finally included. The astigmatisms were investigated using polar value analysis. When TCRP4astig was set as an actual astigmatism, the efficacy of arithmetic or coefficient adjustment of Kastig was evaluated using bivariate analysis. Results The difference between the simulated keratometer astigmatism of the Pentacam (SimKastig) and Kastig was strongly correlated with the difference between TCRP4astig and Kastig. TCRP4astig was different from Kastig in magnitude rather than meridian before and after surgery; the preoperative difference was due to the posterior cornea only; however, the postoperative difference was observed in both anterior and posterior parts. For arithmetic adjustment, 0.28 D and 0.27 D were subtracted from the preoperative and postoperative magnitudes of Kastig, respectively. For coefficient adjustment, the preoperative and postoperative magnitudes of Kastig were multiplied by 0.80 and 0.66, respectively. By arithmetic or coefficient adjustment, the difference between TCRP4astig and adjusted Kastig would be less than 0.75 D in magnitude for 95% of cases. Conclusions Kastig was successfully adjusted to TCPR4astig before and after myopic keratorefractive surgery in cases of WTR. For use of TCRP4astig directly, SimKastig and Kastig should be matched.
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Feizi S, Naderan M, Ownagh V, Sadeghpour F. Distribution of the anterior, posterior, and total corneal astigmatism in healthy eyes. Int Ophthalmol 2017; 38:481-491. [PMID: 28289951 DOI: 10.1007/s10792-017-0483-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 02/24/2017] [Indexed: 12/26/2022]
Abstract
PURPOSE To evaluate the magnitude and axis orientation of the anterior, posterior, and total corneal astigmatism in normal healthy eyes of an Iranian population. METHODS In a prospective cross-sectional study, ophthalmic and anterior segment parameters of 153 healthy eyes of 153 subjects were evaluated by Galilei dual Scheimpflug analyzer. The magnitude and axis orientation [with-the-rule (WTR), against-the-rule (ATR), and oblique] of the anterior, posterior, and total corneal astigmatism measurements (ACA, PCA, and TCA) were compared according to the age, sex, and other ophthalmic parameters. RESULTS The mean ± SD age of the study population was 30 ± 5.9 years. The mean magnitude was 1.09 ± 0.76 diopters (D) for ACA, 0.30 ± 0.13 D for PCA, and 1.08 ± 0.77 D for TCA. Males had a significantly higher magnitude of PCA than females (p = 0.041). Most eyes had a WTR anterior astigmatism and an ATR posterior astigmatism. The WTR astigmatism had a higher mean magnitude compared to the ATR and oblique astigmatism in all the astigmatism groups, with a significant difference in the ACA and TCA groups (p < 0.05). PCA magnitude exceeded 0.50 D in only 7.8% of the subjects. ACA, PCA, and TCA were significantly correlated with each other and also had a significant correlation with the anterior and posterior maximum corneal elevation measurements (p < 0.001). CONCLUSION The results of this study although are limited due to the small number of participants and confined to our demographics, provided information regarding a population that was not described before and may be helpful in obtaining optimum results in astigmatism correction in refractive surgery or designing new intraocular lenses.
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Affiliation(s)
- Sepehr Feizi
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Naderan
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. .,Eye Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Qazvin Square, Tehran, 1336616351, Iran.
| | - Vahid Ownagh
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Fatemeh Sadeghpour
- Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Zhang B, Ma JX, Liu DY, Guo CR, Du YH, Guo XJ, Cui YX. Effects of posterior corneal astigmatism on the accuracy of AcrySof toric intraocular lens astigmatism correction. Int J Ophthalmol 2016; 9:1276-82. [PMID: 27672591 DOI: 10.18240/ijo.2016.09.07] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 11/16/2015] [Indexed: 12/30/2022] Open
Abstract
AIM To evaluate the effects of posterior corneal surface measurements on the accuracy of total estimated corneal astigmatism. METHODS Fifty-seven patients with toric intraocular lens (IOL) implantation and posterior corneal astigmatism exceeding 0.5 diopter were enrolled in this retrospective study. The keratometric astigmatism (KA) and total corneal astigmatism (TA) were measured using a Pentacam rotating Scheimpflug camera to assess the outcomes of AcrySof IOL implantation. Toric IOLs were evaluated in 26 eyes using KA measurements and in 31 eyes using TA measurements. Preoperative corneal astigmatism and postoperative refractive astigmatism were recorded for statistical analysis. The cylindrical power of toric IOLs was estimated in all eyes. RESULTS In all cases, the difference of toric IOL astigmatism magnitude between KA and TA measurements for the estimation of preoperative corneal astigmatism was statistically significant. Of a total of 57 cases, the 50.88% decreased from Tn to Tn-1, and 10.53% decreased from Tn to Tn-2. In all cases, 5.26% increased from Tn to Tn+1. The mean postoperative astigmatism within the TA group was significantly lower than that in the KA group. CONCLUSION The accuracy of total corneal astigmatism calculations and the efficacy of toric IOL correction can be enhanced by measuring both the anterior and posterior corneal surfaces using a Pentacam rotating Scheimpflug camera.
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Affiliation(s)
- Bin Zhang
- Department of Ophthalmology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China
| | - Jing-Xue Ma
- Department of Ophthalmology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China
| | - Dan-Yan Liu
- Department of Ophthalmology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China
| | - Cong-Rong Guo
- Department of Ophthalmology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China
| | - Ying-Hua Du
- Department of Ophthalmology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China
| | - Xiu-Jin Guo
- Department of Ophthalmology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China
| | - Yue-Xian Cui
- Department of Ophthalmology, the Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China
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Jing Q, Tang Y, Qian D, Lu Y, Jiang Y. Posterior Corneal Characteristics of Cataract Patients with High Myopia. PLoS One 2016; 11:e0162012. [PMID: 27603713 PMCID: PMC5014344 DOI: 10.1371/journal.pone.0162012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 08/16/2016] [Indexed: 11/18/2022] Open
Abstract
Purpose To evaluate the characteristics of the posterior corneal surface in patients with high myopia before cataract surgery. Methods We performed a cross-sectional study at the Eye and ENT Hospital of Fudan University, Shanghai, China. Corneal astigmatism and axial length were measured with a rotating Scheimpflug camera (Pentacam) and partial coherence interferometry (IOLMaster) in a high-myopia study group of 167 eyes (axial length ≥ 26 mm) and a control group of 150 eyes (axial length > 20 mm and < 25 mm). Results Total corneal astigmatism and anterior corneal astigmatism values were higher in the high-myopia group than in the control group. There was no significant difference in posterior corneal astigmatism between the high-myopia study group and the control group. In the study group, the mean posterior corneal astigmatism (range 0 – −0.9 diopters) was –0.29 diopters (D) ± 0.17 standard deviations (SD). The steep corneal meridian was aligned vertically (60°–120°) in 87.43% of eyes for the posterior corneal surface, and did not change with increasing age. There was a significant correlation (r = 0.235, p = 0.002) between posterior corneal astigmatism and anterior corneal astigmatism, especially when the anterior corneal surface showed with-the-rule (WTR) astigmatism (r = 0.452, p = 0.000). There was a weak negative correlation between posterior corneal astigmatism and age (r = –0.15, p = 0.053) in the high-myopia group. Compared with total corneal astigmatism values, the anterior corneal measurements alone overestimated WTR astigmatism by a mean of 0.27 ± 0.18 D in 68.75% of eyes, underestimated against-the-rule (ATR) astigmatism by a mean of 0.41 ± 0.28 D in 88.89% of eyes, and underestimated oblique astigmatism by a mean of 0.24 ± 0.13 D in 63.64% of eyes. Conclusions Posterior corneal astigmatism decreased with age and remained as ATR astigmatism in most cases of high myopia. There was a significant correlation between posterior corneal astigmatism and anterior corneal astigmatism when anterior corneal astigmatism was WTR. If posterior corneal astigmatism is not accounted for when selecting toric intraocular lenses for high-myopia patients, the use of anterior corneal astigmatism measurements alone will lead to overestimation of WTR astigmatism and underestimation of ATR and oblique astigmatism.
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Affiliation(s)
- Qinghe Jing
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital of Fudan University, Shanghai, China
- Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yating Tang
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital of Fudan University, Shanghai, China
- Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Dongjin Qian
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital of Fudan University, Shanghai, China
- Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yi Lu
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital of Fudan University, Shanghai, China
- Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
| | - Yongxiang Jiang
- Department of Ophthalmology and Vision Science, Eye and ENT Hospital of Fudan University, Shanghai, China
- Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China
- * E-mail:
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Klijn S, van der Sommen CM, Sicam VADP, Reus NJ. Value of posterior keratometry in the assessment of surgically induced astigmatic change in cataract surgery. Acta Ophthalmol 2016; 94:494-8. [PMID: 27011060 DOI: 10.1111/aos.13003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 01/07/2016] [Indexed: 11/29/2022]
Abstract
PURPOSE To investigate the value of posterior keratometry in the assessment of surgically induced astigmatic change (AC) in cataract surgery, with particular emphasis on the influence of test-retest variability. METHODS Seventy-seven eyes of 77 cataract patients scheduled for routine cataract surgery were enrolled. All patients received a 2.2-mm self-sealing scleral incision (n = 24), single-plane clear corneal incision (SPCCI; n = 29) or biplanar clear corneal incision (BPCCI; n = 24). Measurements of anterior and posterior corneal astigmatism were performed with a rotating Scheimpflug camera (Pentacam HR) preoperatively and postoperatively. Two repeated readings were taken preoperatively to assess the role of the test-retest effect. Astigmatic change (AC) was analysed according to the polar value method. RESULTS On the anterior corneal surface, SPCCIs and BPCCIs caused a statistically significant mean flattening of the incisional meridian of 0.37 and 0.27 dioptres (D), respectively. Scleral incisions on average did not cause AC, although steepening, flattening or torque beyond the test-retest effect was observed in individual cases. On the posterior surface, mean power changes in the incisional meridian were below 0.1 D for all incisions, and these changes were of the same order of magnitude as the test-retest effect. CONCLUSION Surgically induced AC of the posterior corneal surface after cataract surgery is of negligible clinical relevance. Moreover, it is of the same order of magnitude as the test-retest variability of the measurement device and therefore cannot (yet) be reliably assessed.
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Affiliation(s)
- Stijn Klijn
- Rotterdam Ophthalmic Institute; Rotterdam The Netherlands
| | | | | | - Nicolaas J. Reus
- Rotterdam Ophthalmic Institute; Rotterdam The Netherlands
- Department of Ophthalmology; Amphia Hospital; Breda The Netherlands
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Song XF, Langenbucher A, Gatzioufas Z, Seitz B, El-Husseiny M. Effect of biometric characteristics on biomechanical properties of the cornea in cataract patient. Int J Ophthalmol 2016; 9:854-7. [PMID: 27366687 DOI: 10.18240/ijo.2016.06.11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Accepted: 03/11/2015] [Indexed: 11/23/2022] Open
Abstract
AIM To determine the impact of biometric characteristics on the biomechanical properties of the human cornea using the ocular response analyzer (ORA) and standard comprehensive ophthalmic examinations before and after standard phacoemulsification. METHODS This study comprised 54 eyes with cataract with significant lens opacification in stages I or II that underwent phacoemulsification (2.8 mm incision). Corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), and corneal-compensated intraocular pressure (IOPcc) were measured by ORA preoperatively and at 1mo postoperatively. Biometric characteristics were derived from corneal topography [TMS-5, anterior equivalent (EQTMS) and cylindric (CYLTMS) power], corneal tomography [Casia, anterior and posterior equivalent (EQaCASIC, EQpCASIA) and cylindric (CYLaCASIA, CYLpCASIA) power], keratometry [IOLMaster, anterior equivalent (EQIOL) and cylindric (CYLIOL) power] and autorefractor [anterior equivalent (EQAR)]. Results from ORA were analyzed and correlated with those from all other examinations taken at the same time point. RESULTS Preoperatively, CH correlated with EQpCASIA and CYLpCASIA only (P=0.001, P=0.002). Postoperatively, IOPg and IOPcc correlated with all equivalent powers (EQTMS, EQIOL, EQAR, EQaCASIA and EQpCASIA) (P=0.001, P=0.007, P=0.001, P=0.015, P=0.03 for IOPg and P<0.001, P=0.003, P<0.001, P=0.009, P=0.014 for IOPcc). CH correlated postoperatively with EQaCASIA and EQpCASIC only (P=0.021, P=0.022). CONCLUSION Biometric characteristics may significantly affect biomechanical properties of the cornea in terms of CH, IOPcc and IOPg before, but even more after cataract surgery.
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Affiliation(s)
- Xue-Fei Song
- Department of Ophthalmology, Saarland University Medical Center, Homburg Saar 66424, Germany; Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai 200011, China
| | - Achim Langenbucher
- Experimental Ophthalmology, Saarland University, Homburg Saar 66424, Germany
| | - Zisis Gatzioufas
- Department of Ophthalmology, Saarland University Medical Center, Homburg Saar 66424, Germany
| | - Berthold Seitz
- Department of Ophthalmology, Saarland University Medical Center, Homburg Saar 66424, Germany
| | - Moatasem El-Husseiny
- Department of Ophthalmology, Saarland University Medical Center, Homburg Saar 66424, Germany
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Accuracy of Total Corneal Astigmatism Measurements With a Scheimpflug Imager and a Color Light-Emitting Diode Corneal Topographer. Am J Ophthalmol 2016; 167:72-8. [PMID: 27131773 DOI: 10.1016/j.ajo.2016.04.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/14/2016] [Accepted: 04/20/2016] [Indexed: 11/22/2022]
Abstract
PURPOSE To determine the accuracy of total corneal astigmatism measurements with a Scheimpflug imager and a color light-emitting diode corneal topographer, and to compare the accuracy of total corneal astigmatism measurements with the accuracy of measurements that are based only on the anterior corneal surface. DESIGN Prospective validity assessment. METHODS This study was conducted at the Rotterdam Ophthalmic Institute, Rotterdam, Netherlands. The study population consisted of 91 eyes of 91 patients with monofocal, non-toric intraocular lenses (IOLs). Refractive astigmatism was measured with the ARK-530A autorefractor (Nidek, Gamagori, Japan). Anterior and total corneal astigmatism were measured with the Pentacam HR (Oculus, Wetzlar, Germany) and the Cassini (i-Optics, The Hague, Netherlands). Under the assumption that refractive astigmatism must equal total corneal astigmatism in these patients, accuracy of the corneal astigmatism measurements was defined as the vectorial difference with the refractive astigmatism, with lower vector differences denoting higher accuracy. RESULTS The median refractive astigmatic magnitude was 0.84 diopter (D). The mean difference vector lengths were 0.61 D, 0.58 D, 0.49 D, and 0.45 D for Pentacam anterior, Cassini anterior, Pentacam total, and Cassini total corneal astigmatism, respectively. The mean difference vector length decreased by 0.12 and 0.13 D for Pentacam and Cassini, respectively, if the total instead of anterior corneal astigmatism was measured. These decreases were statistically significant (P < .001). CONCLUSIONS With Pentacam as well as with Cassini, the accuracy of total corneal astigmatism measurements was higher than that of anterior corneal astigmatism measurements. Measuring total instead of anterior corneal astigmatism may therefore decrease the residual astigmatism in toric IOL implantation.
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Lee KI, Park YL, Kim HS. Analysis of Changes in Anterior, Posterior and Total Corneal Astigmatism after On-Axis Cataract Surgery. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2016. [DOI: 10.3341/jkos.2016.57.1.25] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Kee Il Lee
- Department of Ophthalmology and Visual Science, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Yu Li Park
- Department of Ophthalmology and Visual Science, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Hyun Seung Kim
- Department of Ophthalmology and Visual Science, College of Medicine, The Catholic University of Korea, Seoul, Korea
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Kessel L, Andresen J, Tendal B, Erngaard D, Flesner P, Hjortdal J. Toric Intraocular Lenses in the Correction of Astigmatism During Cataract Surgery: A Systematic Review and Meta-analysis. Ophthalmology 2015; 123:275-286. [PMID: 26601819 DOI: 10.1016/j.ophtha.2015.10.002] [Citation(s) in RCA: 216] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 10/01/2015] [Accepted: 10/01/2015] [Indexed: 10/22/2022] Open
Abstract
TOPIC We performed a systematic review and meta-analysis to evaluate the benefit and harms associated with implantation of toric intraocular lenses (IOLs) during cataract surgery. Outcomes were postoperative uncorrected distance visual acuity (UCDVA) and distance spectacle independence. Harms were evaluated as surgical complications and residual astigmatism. CLINICAL RELEVANCE Postoperative astigmatism is an important cause of suboptimal UCDVA and need for distance spectacles. Toric IOLs may correct for preexisting corneal astigmatism at the time of surgery. METHODS We performed a systematic literature search in the Embase, PubMed, and CENTRAL databases within the Cochrane Library. We included randomized clinical trials (RCTs) if they compared toric with non-toric IOL implantation (± relaxing incision) in patients with regular corneal astigmatism and age-related cataracts. We assessed the risk of bias using the Cochrane Risk of Bias tool. We assessed the quality of evidence across studies using the GRADE profiler software (available at: www.gradeworkinggroup.org). RESULTS We included 13 RCTs with 707 eyes randomized to toric IOLs and 706 eyes randomized to non-toric IOLs; 225 eyes had a relaxing incision. We found high-quality evidence that UCDVA was better in the toric IOL group (logarithm of the minimum angle of resolution [logMAR] mean difference, -0.07; 95% confidence interval [CI], -0.10 to -0.04) and provided greater spectacle independence (risk ratio [RR], 0.51; 95% CI, 0.36-0.71) and moderate quality evidence that toric IOL implantation was not associated with an increased risk of complications (RR, 1.73; 95% CI, 0.60-5.04). Residual astigmatism was lower in the toric IOL group than in the non-toric IOL plus relaxing incision group (mean difference, 0.37 diopter [D]; 95% CI, -0.55 to -0.19). CONCLUSIONS We found that toric IOLs provided better UCDVA, greater spectacle independence, and lower amounts of residual astigmatism than non-toric IOLs even when relaxing incisions were used.
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Affiliation(s)
- Line Kessel
- Department of Ophthalmology, Rigshospitalet - Glostrup, Glostrup, Denmark; National Danish Medicines and Health Authorities, Copenhagen, Denmark.
| | | | - Britta Tendal
- National Danish Medicines and Health Authorities, Copenhagen, Denmark; The Nordic Cochrane Center, Copenhagen, Denmark
| | - Ditte Erngaard
- Department of Ophthalmology, Næstved Hospital, Næstved, Denmark
| | | | - Jesper Hjortdal
- Department of Ophthalmology, Aarhus University Hospital NBG, Aarhus, Denmark
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Park MJ, Park YL, Kim HS. Surgically Induced Posterior Corneal Astigmatism in 2.2 mm Microcoaxial Cataract Surgery Versus 2.85 mm Coaxial Conventional Cataract Surgery. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2015. [DOI: 10.3341/jkos.2015.56.10.1534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Min Ji Park
- Department of Ophthalmology, The Catholic University of Korea College of Medicine, Seoul, Korea
| | - Yu Li Park
- Department of Ophthalmology, The Catholic University of Korea College of Medicine, Seoul, Korea
| | - Hyun Seung Kim
- Department of Ophthalmology, The Catholic University of Korea College of Medicine, Seoul, Korea
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