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Efficacy of Toric Intraocular Lens and Prevention of Axis Misalignment by Optic Capture in Pediatric Cataract Surgery. J Cataract Refract Surg 2021; 47:1417-1422. [PMID: 33797870 DOI: 10.1097/j.jcrs.0000000000000643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Accepted: 03/07/2021] [Indexed: 10/21/2022]
Abstract
PURPOSE To compare the outcomes of intraocular lens (IOL) implantation using toric (T)-IOL and non-toric (N)-IOL in pediatric cataract patients with astigmatism, and to examine the effect of optic capture (OC) on the axis misalignment (AM) of the T-IOLs. SETTING Department of Ophthalmology, Kindai University Hospital, Osaka, Japan. DESIGN Interventional, comparative case study. METHODS Consecutive pediatric patients implanted with T-IOLs or N-IOLs were retrospectively reviewed. In the T-IOL group, the preoperative and postoperative corrected distance visual acuity (CDVA) and AM were compared in patients with and without OC. RESULTS The T-IOL group included 14 eyes of 11 patients, while the N-IOL group included 22 eyes of 15 patients. One year after surgery, the mean ocular cylinder (1.38 ± 0.80 D) was significantly smaller than the average corneal cylinder (3.33 ± 1.24 D) in the T-IOL group (P = .00012, Wilcoxon signed-rank test). The mean preoperative and 1-year postoperative CDVA (logMAR) were 0.57/0.003 (T-IOL) and 0.71/0.09 (N-IOL), respectively. The AM at 1 week and 1 year after surgery was 2.6° ± 3.7° and 4.4° ± 3.1° for the OC group, and 13.3° ± 8.8° and 18.5° ± 14.8°, for the non-OC group, respectively. The AM was significantly smaller in the OC group than that in non-OC group (P = .009, Mann-Whitney U test) at postoperative 1 week. CONCLUSION T-IOL implantation is effective in correcting astigmatism in pediatric cataract patients with astigmatism, and the OC technique is likely to achieve lower AM of the T-IOL.
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Abstract
OBJECTIVES To determine the distribution of keratoconus indices in normal children 6 to 12 years of age. METHODS This cross-sectional study was conducted in children living in urban and rural areas of Shahroud, northeast Iran in 2015. After careful optometric examinations, the Pentacam was used for corneal imaging and measurement of keratoconus indices. RESULTS Of 5,620 students who participated in the study, the data of the right eye of 4,947 children were analyzed after applying the exclusion criteria. The mean age of all children was 9.23±1.71 years (range: 6-12 years). The mean and 95% confidence intervals (in the parentheses) of index of surface variance (ISV), index of vertical asymmetry, keratoconus index (KI), central keratoconus index (CKI), index of height asymmetry, index of height decentration (IHD), and average pachymetric progression index (PPIAve) was 17.770 (17.610-17.930), 0.137 (0.135-0.139), 1.022 (1.022-1.023), 1.010 (1.010-1.010), 3.299 (3.230-3.368), 0.007 (0.007-0.008), and 0.948 (0.943-0.952), respectively. The results of multilevel mixed-effects linear regression analysis showed that ISV, KI, CKI, IHD, and PPIAve were significantly higher in girls. Index of surface variance and CKI were higher in urban students, and PPIAve was higher in rural students. Except for PPIAve, which was increased with increasing age, the mean values of other keratoconus indices were significantly lower in 12-year-old students compared with 6-year-old ones. CONCLUSION The results provide valuable information about normal distribution of keratoconus indices in children aged 6 to 12 years. These findings can be used in future research and detection of abnormal cases in the clinical setting.
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Rozema JJ, Hershko S, Tassignon M, Lorenz K, von Trentini M, Sala Pomares E, Corral MJG, Bataille L, Alió JL, Jongenelen S, Ruiz‐Hidalgo I, Rauscher FG, Blüsch MT, Dawczynski J, Wiedemann P, Mosca L, Guccione L, Riso M, Toro ME, Rosati A, Duch F, Escude R, Martinez A, Morilla‐Grasa A, Peris‐Martínez C, Díez Ajenjo A, Garcia Domene C, De Febrer MB, Solans TT, Gazdik AV, Varssano D, Gold B, Toto L, Mastropasqua A, Mastropasqua L, Fasce F, Spinelli A, Knutsson K, Fogliato G. The components of adult astigmatism and their age‐related changes. Ophthalmic Physiol Opt 2019; 39:183-193. [DOI: 10.1111/opo.12616] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 03/19/2019] [Indexed: 12/01/2022]
Affiliation(s)
- Jos J Rozema
- Department of Ophthalmology Antwerp University Hospital Edegem Belgium
- Department of Medicine and Health Sciences University of Antwerp Wilrijk Belgium
| | - Sarah Hershko
- Department of Ophthalmology Antwerp University Hospital Edegem Belgium
- Department of Medicine and Health Sciences University of Antwerp Wilrijk Belgium
| | - Marie‐José Tassignon
- Department of Ophthalmology Antwerp University Hospital Edegem Belgium
- Department of Medicine and Health Sciences University of Antwerp Wilrijk Belgium
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Abstract
PURPOSE To examine internal astigmatism (IA) in myopes and non-myopes using a new method to assess compensation of corneal astigmatism (CA) by IA, to look for predictors of high IA in young adult myopes, and to determine if as CA changes IA changes to reduce refractive astigmatism (RA) in an active compensatory process in myopes. METHODS Right eye keratometry and cycloplegic autorefraction were measured annually over 14 years in 367 myopes and once in 204 non-myopes age- (mean 21.91 ± 1.47 years), gender-, and ethnicity-matched to myopes at year 12. CA and RA at the corneal plane were expressed as J0, J45. IA = RA - CA. Inverse power transformation provided cylinder power and axis of IA for the compensation factor (IA/CA). Analyses included (1) paired and unpaired t-tests (refractive data), (2) chi-square tests (distributions of compensation factor), (3) logistic regression analysis (predictors of high IA), and (4) linear mixed models (time effect on RA, CA, and IA). RESULTS The magnitude of IAJ0 varied by refractive error (myopes -0.25 ± 0.24 vs. non-myopes -0.32 ± 0.21, p < 0.001). Compensation of CA by IA was poorer in myopes than non-myopes (χ p < 0.001). When matched by CA, compensation remained poorer in myopes than non-myopes (χ all p ≤ 0.04). Within each refractive group, compensation was better when CA was low than high (χ p < 0.001). When CA was low in myopes, high IA (≥1.00D) was less likely (p = 0.01). Longitudinal follow-up of myopes found no evidence for an active compensatory role for IA as CA increased over time. There were differences in IAJ0 by ethnicity over time (p < 0.0001). CONCLUSIONS In myopic and non-myopic eyes with low amounts of CA, IA may reduce CA's contribution to RA, but IA is not a constant. However, there is no evidence for an active compensatory role for IA reducing CA in myopes.
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New regression formula for toric intraocular lens calculations. J Cataract Refract Surg 2016; 42:663-71. [DOI: 10.1016/j.jcrs.2016.02.038] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Revised: 01/29/2016] [Accepted: 02/01/2016] [Indexed: 11/23/2022]
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Abulafia A, Hill WE, Franchina M, Barrett GD. Comparison of Methods to Predict Residual Astigmatism After Intraocular Lens Implantation. J Refract Surg 2015; 31:699-707. [DOI: 10.3928/1081597x-20150928-03] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 08/10/2015] [Indexed: 11/20/2022]
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Abulafia A, Barrett GD, Kleinmann G, Ofir S, Levy A, Marcovich AL, Michaeli A, Koch DD, Wang L, Assia EI. Prediction of refractive outcomes with toric intraocular lens implantation. J Cataract Refract Surg 2015; 41:936-44. [DOI: 10.1016/j.jcrs.2014.08.036] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Revised: 08/17/2014] [Accepted: 08/19/2014] [Indexed: 11/26/2022]
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Koch DD, Jenkins RB, Weikert MP, Yeu E, Wang L. Correcting astigmatism with toric intraocular lenses: Effect of posterior corneal astigmatism. J Cataract Refract Surg 2013; 39:1803-9. [DOI: 10.1016/j.jcrs.2013.06.027] [Citation(s) in RCA: 160] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Revised: 06/12/2013] [Accepted: 06/14/2013] [Indexed: 10/26/2022]
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Pärssinen O, Kauppinen M, Kaprio J, Koskenvuo M, Rantanen T. Heritability of corneal refraction and corneal astigmatism: a population-based twin study among 66- to 79-year-old female twins. Acta Ophthalmol 2013; 91:140-4. [PMID: 22280520 DOI: 10.1111/j.1755-3768.2011.02332.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To examine the heritability of corneal refraction power (CR) and corneal astigmatism (AST) in older women. METHODS Corneal refraction and AST were measured by IOL master in 52 monozygotic (MZ) and 47 dizygotic (DZ) female twin pairs aged 66-79 years. The relative contribution of genetic and environmental factors to individual differences in CR was estimated by applying an independent pathway model to the twin data and AST by intraclass correlations (ICC). RESULTS For the right eye, mean CR was 44.58 dioptres (D) (standard deviation (SD) ±1.28) When comparing CR of the right and left eye between MZ and DZ, no significant difference was found. Mean AST was 0.77 D (SD ±0.44) with no differences observed either between the MZ and the DZ individuals, or between the left and the right eyes. ICCs between the sisters for CR were, for the right eye, 0.882 and 0.378 for MZ and DZ, respectively, and for the left eye 0.855 and 0.358. For AST of the right eye, the ICCs were 0.533 and 0.096 for the MZ and DZ pairs, respectively, and for the left eye, the MZ and DZ correlations were 0.396 and 0.299. Quantitative genetic modelling showed that 81% of the variance in CR could be explained by genetic factors, additive genetic factors explaining 62% (95% confidence interval [CI] 44% -86%) and dominant genetic effect 19% (95% CI 7-49%) of the variance in CR. Different models were constructed to explain the heredity of AST. None of these models gave meaningful results, although the ICC values for MZ were higher than those for DZ. CONCLUSIONS Most of the variance in CR among older Finnish women could be explained by genetic factors.
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Affiliation(s)
- Olavi Pärssinen
- Department of Ophthalmology, Central Hospital of Central Finland, Jyväskylä, Finland.
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Chen W, Zuo C, Chen C, Su J, Luo L, Congdon N, Liu Y. Prevalence of corneal astigmatism before cataract surgery in Chinese patients. J Cataract Refract Surg 2012; 39:188-92. [PMID: 23141077 DOI: 10.1016/j.jcrs.2012.08.060] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2011] [Revised: 08/09/2012] [Accepted: 08/17/2012] [Indexed: 10/27/2022]
Abstract
PURPOSE To assess the demographics and distribution of corneal astigmatism before cataract surgery in Chinese patients. SETTING State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China. DESIGN Clinic-based cross-sectional study. METHODS From July 2009 to May 2011, preoperative bilateral partial coherence interferometry (IOLMaster) was performed in consecutive patients having cataract surgery. Patient demographics and keratometric data were recorded. RESULTS The mean age of the 2849 patients (4831 eyes) was 70.56 years ± 9.55 (SD); there was a predominance of women patients (64.0%). The mean axial length was 23.58 ± 1.13 mm. The mean corneal astigmatism in this cohort was 1.01 D (range 0.05 to 6.59 D). Corneal astigmatism was between 0.25 D and 1.25 D in 67.7% of eyes, 1.25 D or higher in 27.5% eyes, and less than 0.25 D in 4.8% of eyes. Astigmatism was with the rule in 25.1% of eyes, against the rule (ATR) in 58.2% of eyes, and oblique in 16.7% of eyes. The mean steep keratometry measurement was 44.76 ± 1.56 D. Against-the-rule astigmatism increased significantly with older age. CONCLUSIONS Corneal astigmatism largely fell between 0.25 D and 1.25 D in these predominantly elderly female Chinese patients, and ATR astigmatism increased with age. FINANCIAL DISCLOSURE No author has a financial or proprietary interest in any material or method mentioned.
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Affiliation(s)
- Weirong Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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Konradsen TR, Koivula A, Kugelberg M, Zetterström C. Corneal curvature, pachymetry, and endothelial cell density in Marfan syndrome. Acta Ophthalmol 2012; 90:375-9. [PMID: 21726424 DOI: 10.1111/j.1755-3768.2010.01996.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
PURPOSE To evaluate corneal curvature, pachymetry, and endothelial cell density (ECD) in Marfan syndrome (MFS). METHODS A case-control study in which K values, pachymetry, and ECD were compared in 39 MFS eyes and 40 control eyes matched for age and refraction was conducted. MFS eyes with lens subluxation also were compared with eyes without subluxation. RESULTS The mean K(med) value in MFS eyes was lower than in the control eyes, 42.2 ± 1.9 versus 43.4 ± 1.4 dioptres (D), respectively (p = 0.02). Fifteen MFS eyes (38%) and three control eyes (8%) had K(med) values below 41.5 D (p = 0.0012). MFS eyes had generally more corneal astigmatism than control eyes, 1.1 ± 0.9 versus 0.8 ± 0.4 D (p = 0.035), and MFS eyes with lens subluxation had more corneal astigmatism than those without, 1.6 ± 1.1 versus 0.6 ± 0.3 D (p = 0.0002). Nine MFS eyes with corneal astigmatism exceeding 1.5 D also had a subluxated lens. No eyes had keratoconus. The mean pachymetry value was lower in MFS eyes compared to the controls, 485 ± 54.5 versus 514 ± 37.3 μm (p = 0.007); 24 MFS eyes (62%) and 10 control eyes (25%) had measurements below 500 μm (p = 0.01). The mean ECD values were similar in MFS and control eyes, 2815 ± 430 versus 2858 ± 458 cells/mm(2) (p = 0.66). The mean K value, pachymetry, and ECD values did not differ between MFS eyes with and without lens subluxation. CONCLUSION Decreased K values and pachymetry could indicate MFS regardless of subluxation. High corneal astigmatism is associated with subluxation in MFS. Subluxation should be identified in MFS eyes with high corneal astigmatism.
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Affiliation(s)
- Tiina R Konradsen
- Anterior Segment Department, St Erik's Eye Hospital, Stockholm, Sweden.
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KhabazKhoob M, Hashemi H, Yazdani K, Mehravaran S, Yekta A, Fotouhi A. Keratometry measurements, corneal astigmatism and irregularity in a normal population: the Tehran Eye Study. Ophthalmic Physiol Opt 2010; 30:800-5. [DOI: 10.1111/j.1475-1313.2010.00732.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Ferrer-Blasco T, Montés-Micó R, Peixoto-de-Matos SC, González-Méijome JM, Cerviño A. Prevalence of corneal astigmatism before cataract surgery. J Cataract Refract Surg 2009; 35:70-5. [PMID: 19101427 DOI: 10.1016/j.jcrs.2008.09.027] [Citation(s) in RCA: 272] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2008] [Revised: 09/24/2008] [Accepted: 09/24/2008] [Indexed: 10/21/2022]
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Oshika T, Okamoto C, Samejima T, Tokunaga T, Miyata K. Contrast sensitivity function and ocular higher-order wavefront aberrations in normal human eyes. Ophthalmology 2006; 113:1807-12. [PMID: 16876865 DOI: 10.1016/j.ophtha.2006.03.061] [Citation(s) in RCA: 115] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2005] [Revised: 03/23/2006] [Accepted: 03/23/2006] [Indexed: 11/16/2022] Open
Abstract
PURPOSE To investigate the relation between contrast sensitivity function and ocular higher-order wavefront aberrations in normal human eyes. STUDY DESIGN Prospective observational case series. PARTICIPANTS Three hundred seven eyes of 161 normal subjects, ranging in age from 15 to 60 years (30.9+/-8.0 [mean +/- standard deviation]). METHODS Ocular higher-order aberrations were measured for a 4-mm pupil using the Hartmann-Shack wavefront analyzer. The root-mean-square of the third- and fourth-order Zernike coefficients was used to represent comalike and spherical-like aberrations, respectively. We measured contrast sensitivity, low-contrast visual acuity (VA), and letter contrast sensitivity. From the contrast sensitivity data, the area under the log contrast sensitivity function (AULCSF) was calculated. Pupil diameter in a photopic condition was recorded using a digital camera. RESULTS Multiple linear regression analysis revealed that comalike aberration (P = 0.002) was significantly associated with AULCSF, but spherical-like aberration (P = 0.200), age (P = 0.185), and photopic pupil diameter (P=0.252) were not. Comalike aberration showed a significant correlation with low-contrast VA (P<0.001), but spherical-like aberration (P = 0.293), age (P = 0.266), and pupil diameter (P = 0.756) did not. Comalike aberration was found to be significantly associated with letter contrast sensitivity (P<0.001), but spherical-like aberration (P=0.082), age (P = 0.370), and pupil diameter (P = 0.160) were not. CONCLUSIONS In normal human eyes, comalike aberration of the eye significantly influences contrast sensitivity function.
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Affiliation(s)
- Tetsuro Oshika
- Department of Ophthalmology, Institute of Clinical Medicine, University of Tsukuba, Tsukuba, Ibaraki, Japan.
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Kee CS, Hung LF, Qiao-Grider Y, Ramamirtham R, Smith EL. Astigmatism in monkeys with experimentally induced myopia or hyperopia. Optom Vis Sci 2005; 82:248-60. [PMID: 15829845 PMCID: PMC1810233 DOI: 10.1097/01.opx.0000159357.61498.6b] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
PURPOSE Astigmatism is the most common ametropia found in humans and is often associated with large spherical ametropias. However, little is known about the etiology of astigmatism or the reason(s) for the association between spherical and astigmatic refractive errors. This study examines the frequency and characteristics of astigmatism in infant monkeys that developed axial ametropias as a result of altered early visual experience. METHODS Data were obtained from 112 rhesus monkeys that experienced a variety of lens-rearing regimens that were intended to alter the normal course of emmetropization. These visual manipulations included form deprivation (n = 13); optically imposed defocus (n = 48); and continuous ambient lighting with (n = 6) or without optically imposed defocus (n = 6). In addition, data from 19 control monkeys and 39 infants reared with an optically imposed astigmatism were used for comparison purposes. The lens-rearing period started at approximately 3 weeks of age and ended by 4 to 5 months of age. Refractive development for all monkeys was assessed periodically throughout the treatment and subsequent recovery periods by retinoscopy, keratometry, and A-scan ultrasonography. RESULTS In contrast to control monkeys, the monkeys that had experimentally induced axial ametropias frequently developed significant amounts of astigmatism (mean refractive astigmatism = 0.37 +/- 0.33 D [control] vs. 1.24 +/- 0.81 D [treated]; two-sample t-test, p < 0.0001), especially when their eyes exhibited relative hyperopic shifts in refractive error. The astigmatism was corneal in origin (Pearson's r; p < 0.001 for total astigmatism and the JO and J45 components), and the axes of the astigmatism were typically oblique and bilaterally mirror symmetric. Interestingly, the astigmatism was not permanent; the majority of the monkeys exhibited substantial reductions in the amount of astigmatism at or near the end of the lens-rearing procedures. CONCLUSIONS In infant monkeys, visual conditions that alter axial growth can also alter corneal shape. Similarities between the astigmatic errors in our monkeys and some astigmatic errors in humans suggest that vision-dependent changes in eye growth may contribute to astigmatism in humans.
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Affiliation(s)
- Chea-Su Kee
- College of Optometry, University of Houston, Houston, Texas 77204-2020, USA.
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Topuz H, Ozdemir M, Cinal A, Gumusalan Y. Age-Related Differences in Normal Corneal Topography. Ophthalmic Surg Lasers Imaging Retina 2004. [DOI: 10.3928/1542-8877-20040701-06] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Abstract
We investigated pseudophakic residual astigmatism in order to minimize postoperative refractive astigmatism. We examined 110 eyes of 87 patients who had undergone phacoemulsification with small incision and posterior chamber intraocular lens (IOL) implantation. Corneal astigmatism was measured using an autokeratometer (RK-5, canon), refractive astigmatism by manifest refraction, and residual astigmatism by vector analysis. Mean pseudophakic residual astigmatism was +0.47 x 176 degrees, predominantly against-the-rule. Variations of pseudophakic residual astigmatism according to sex, age and IOL type were not statistically significant. When performing cataract surgery as refractive surgery, we may consider that pseudophakic residual astigmatism is approximately 0.50D against-the-rule.
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Affiliation(s)
- Jung Gn Bae
- Department of Ophthalmology, Eulji University College of Medicine, Seoul, Korea
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Abstract
To determine whether developing primate eyes are capable of growing in a manner that eliminates astigmatism, we reared infant monkeys with cylindrical spectacle lenses in front of one or both eyes that optically simulated with-the-rule, against-the-rule, or oblique astigmatism (+1.50-3.00x90, x180, x45 or x135). Refractive development was assessed by retinoscopy, keratometry and A-scan ultrasonography. In contrast to control monkeys, the cylinder-lens-reared monkeys developed significant amounts of astigmatism. The astigmatism was corneal in nature, bilaterally mirror symmetric and oblique in axis, and reversible. The ocular astigmatism appeared to be due to a reduction in the rate of corneal flattening along the steeper meridian while the other principal meridian appeared to flatten at a more normal rate. However, regardless of the orientation of the optically imposed astigmatism, the axis of the ocular astigmatism was not appropriate to compensate for the astigmatic error imposed by the treatment lenses. Our results indicate that visual experience can alter corneal shape, but there was no evidence that primates have an active, visually regulated "sphericalization" mechanism.
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Affiliation(s)
- Chea-su Kee
- College of Optometry, University of Houston, 505 J Davis Armistead Building, Houston, TX 77204-2020, USA
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Abstract
PURPOSE To investigate gender- and age-related differences in the corneal topography of a normal population. METHODS One hundred thirty-two topographic examinations were collected from 100 patients ranging in age from 23 to 83 years (average, 57.35+/-17.38 years). Data were segregated by gender and further divided into younger (less than 50 years) and older (50 years or more) age groups. The topographic indices of Surface Regularity Index, Surface Asymmetry Index, Irregular Astigmatism Index, Standard Deviation of Corneal Power, Corneal Eccentricity Index, Coefficient of Variation of Corneal Power, Simulated Keratometry 1 and 2, and Average Corneal Power were examined. The astigmatism pattern and corneal irregularity were determined and compared with respect to gender and age. RESULTS The corneas of older men were flatter than those of older women (p < 0.001). The vertical corneal meridian, but not the horizontal meridian, showed statistically significant gender-related changes with aging (p < 0.001). Older men had a significantly higher potential for against-the-rule astigmatism than women (p < 0.001). Corneal irregularity (measured in terms of the Surface Regularity Index and Irregular Astigmatism Index) increased with age (p < 0.001 and p < 0.001, respectively), although there was no gender-related difference. In the younger group, no gender-related differences in corneal curvature or astigmatism pattern were found. CONCLUSION Aging influences changes in patterns of astigmatism differently in men and women. Decreases in levels of sex hormones may play a role in gender-related changes in corneal structure with age.
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Affiliation(s)
- T Goto
- Lions Eye Research Laboratories, LSU Eye Center, Louisiana State University Health Sciences Center, New Orleans 70112-2234, USA
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