Refractive Error Induced by Intraocular Lens Tilt After Intrascleral Intraocular Lens Fixation

Abstract Purpose To investigate the spherical shift of Intraocular lens (IOL) tilt after intrascleral fixationMethods We retrospectively reviewed the medical records of patients who underwent flanged intrascleral IOL fixation with transconjunctival 25- or 27-gauge pars plana vitrectomy at the Department of Ophthalmology of Jikei University Hospital with a minimum follow-up duration of three months. Second-generation anterior segment optical coherence tomography (CASIA2; TOMEY) was used to obtain the tilt and decentration of intrasclerally fixated IOL and postoperative anterior chamber depth. We investigated the relationship of the refractive error with these parameters, axial length, and keratometry. In addition to the clinical investigation, we performed optical simulations using the Zemax optical design program for studying the spherical shift of the IOL tilt by means of the through-focus response and change of spherical equivalent power.Results The study involved 72 eyes of 67 patients. The degree of IOL tilt was correlated with the amount of refractive error (Spearman's rank correlation coefficient [CC] = −0.32; P = 0.006). In particular, a tilt angle greater than 10° strongly influenced the refractive error. Postoperative anterior chamber depth also correlated with the refractive error (CC = 0.50; P < 0.001). The refractive error did not correlate with decentration (CC = −0.17; P = 0.15), axial length (CC = −0.08; P = 0.49), and keratometry (CC = −0.06; P =0.64). Optical simulations using the Zemax optical design program also showed a myopic shift exponentially as the tilt becomes greater. Conclusion An IOL tilt greater than 10 ° induces refractive error.

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Quantification of Trabecular-Iris Contact and its Prevalence by Optical Coherence Tomography in a Healthy Caucasian Population

European Journal of Ophthalmology ◽

10.5301/ejo.5000919 ◽

2016 ◽

Vol 27 (4) ◽

pp. 417-422 ◽

Cited By ~ 4

Author(s):

José Ignacio Fernández-Vigo ◽

Lucía De-Pablo-Gómez-De-Liaño ◽

Cristina Fernández-Vigo ◽

Inés Sánchez-Guillén ◽

Enrique Santos-Bueso ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Refractive Error ◽

Axial Length ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Fourier Domain ◽

Optical Coherence ◽

Cross Sectional

Purpose To determine the prevalence of trabecular-iris contact (TIC) and quantify this contact in healthy Caucasian individuals using Fourier-domain optical coherence tomography (FD-OCT). Methods For this cross-sectional study, 2,012 eyes of 1,006 healthy subjects were recruited among individuals undergoing a routine ophthalmologic checkup. In each participant, age, sex, intraocular pressure, and spherical refractive error were first recorded along with anterior chamber depth and volume, central corneal thickness measured with the Pentacam, and axial length with the IOLMaster. Anterior chamber angle variables and the presence of TIC in the horizontal quadrants were determined by anterior segment FD-OCT (RTVue 100®). When TIC was observed, TIC length (TICL) and its percentage in relation to the length of the trabecular meshwork (TICL percentage) were also measured. Results Trabecular-iris contact in the horizontal quadrants was observed in 34 eyes of 25 patients, representing 1.6% of the total number of eyes examined. In this subgroup of individuals, mean age was 55.8 years, 84% were women, and spherical refractive error ranged from -0.25 to 8.25 D. Eyes with TIC showed an angle width of less than 23.2 degrees and axial length shorter than 23.7 mm. Mean TICL was 239 ± 79 μm (103-495 μm) and mean TICL percentage was 46.9% ± 13.9% (17.2%-76.3%). Conclusions The prevalence of TIC was low in this population. Fourier-domain optical coherence tomography emerged as useful to assess its prevalence and quantify the extent of TIC.

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Effects of Anterior Chamber Depth and Axial Length on Refractive Error after Intraocular Lens Implantation

Journal of the Korean Ophthalmological Society ◽

10.3341/jkos.2010.51.2.195 ◽

2010 ◽

Vol 51 (2) ◽

pp. 195 ◽

Cited By ~ 17

Author(s):

Hyo-Sung Maeng ◽

Eun Hye Ryu ◽

Tae-Young Chung ◽

Eui-Sang Chung

Keyword(s):

Anterior Chamber ◽

Intraocular Lens ◽

Refractive Error ◽

Axial Length ◽

Anterior Chamber Depth ◽

Intraocular Lens Implantation ◽

Lens Implantation

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Refractive error and biometrics of anterior segment of eyes of healthy young university students in Japan

Scientific Reports ◽

10.1038/s41598-019-51920-4 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

Kumiko Kato ◽

Mineo Kondo ◽

Maki Takeuchi ◽

Koji Hirano

Keyword(s):

University Students ◽

Anterior Chamber ◽

Refractive Error ◽

Axial Length ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Japanese University ◽

The Mean ◽

Corneal Diameter

Abstract To determine the parameters of the anterior segment of eyes that are significantly associated with the refractive error in healthy young Japanese university students. This was a cross-sectional observational study of 229 healthy Japanese university students (men: women,147:82) whose age ranged between 20 to 29 years. Univariate and multivariate linear regression analyses were performed to identify the factors that were significantly correlated with the refractive error. The independent variables included age, sex, axial length, anterior chamber depth, corneal diameter, curvature of anterior surface of cornea, and central corneal thickness. The mean refractive error (spherical equivalent) was −4.1 ± 2.7 diopters (D) with a range of −12.5 to +0.5 D, and the mean axial length was 25.4 ± 1.3 mm with a range of 22.4 to 29.0 mm. Pearson univariate correlation analysis found that the refractive error was significantly and negatively correlated with the axial length (R = −0.82, P < 0.001), deeper anterior chamber (R = −0.30, P < 0.001), and larger corneal diameter (R = −0.21, P = 0.001). Multiple regression analysis showed that the refractive error was significantly associated with a longer axial length (P < 0.001), a deeper anterior chamber (P < 0.001), and a flatter corneal curvature (P < 0.001).The biometric values of the anterior segment of the eyes should make the eye more hyperopic which would reduce the myopia-inducing lengthening of the axial length.

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Algorithmic intraocular lens power calculation formula selection by keratometry, anterior chamber depth and axial length

Acta Ophthalmologica ◽

10.1111/aos.14956 ◽

2021 ◽

Author(s):

Jung Wan Kim ◽

Youngsub Eom ◽

Eun Gyu Yoon ◽

Young Choi ◽

Jong Suk Song ◽

...

Keyword(s):

Anterior Chamber ◽

Intraocular Lens ◽

Axial Length ◽

Anterior Chamber Depth ◽

Power Calculation ◽

Calculation Formula ◽

Intraocular Lens Power Calculation ◽

Intraocular Lens Power ◽

Lens Power ◽

Lens Power Calculation

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A calculator proposal for estimating refractive error after 3 years using the onset biometric values in primary school children: a cohort study

10.22541/au.161971139.95061043/v1 ◽

2021 ◽

Author(s):

Feride Tuncer Orhan ◽

Haluk Huseyin Gürsoy

Keyword(s):

Primary School ◽

Anterior Chamber ◽

Refractive Error ◽

Axial Length ◽

Anterior Chamber Depth ◽

Primary School Children ◽

Optical Parameters ◽

Spherical Equivalent ◽

Final Data ◽

The Mean

Aim To evaluate consecutive measurements of the biometric parameters, age, and refraction error in a Turkish population at primary school age. Materials and Methods A total of 197 children aged between 7-12 years were included. The data of three consecutive measurements of children, who were examined at least once a year for three years using both cycloplegic auto-refractometry and optical biometry, were used in this retrospective study. Spherical equivalent <-0.50D was considered to be myopic; >+0.75D was considered to be hypermetropic. Age, gender, body mass index, spherical equivalent, axial length, anterior chamber depth, central corneal thickness, keratometry, and lens thickness were analyzed. The onset data obtained in 2013 whereas, the final data were from 2015. Logistic and Cox regression analyses were performed (p<0.05). Results The mean of the onset and the final spherical equivalents were 0.19D (0.56), and 0.08D (0.80), respectively. The myopia prevalence was increased among refractive errors in observation periods (univariable analysis p=0.029; multivariable analysis p=0.017). The onset axial length (HR:4.55, 95%CI:2.87-7.24, p<0.001), keratometry (HR:2.04, 95%CI:1.55-2.67, p<0.001) and age (HR:0.73, 95%CI: 0.57-0.92, p=0.009) correlated myopia progression. To calculate the estimated spherical equivalent, the onset data were included in the logistic regression model. The onset data of spherical equivalent (β=0.916, p<0.001), axial length (β=-0.451, p<0.001), anterior chamber depth (β=0.430, p=0.005) and keratometry (β=-0.172, p<0.001) were found to be significantly associated with the mean SE at the final data. Conclusions To calculate the estimated spherical equivalent following three years, an equation was proposed. The estimated refractive error of children can be calculated by using the proposed equation with the associated onset optical parameters.

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Evaluation of Anterior Segment’s Structures in Tilted Disc Syndrome

Journal of Ophthalmology ◽

10.1155/2016/5185207 ◽

2016 ◽

Vol 2016 ◽

pp. 1-4 ◽

Cited By ~ 3

Author(s):

Ercan Ozsoy ◽

Abuzer Gunduz ◽

Ersin Ersan Demirel ◽

Tongabay Cumurcu

Keyword(s):

Anterior Chamber ◽

Axial Length ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Control Group ◽

Tilted Disc Syndrome ◽

Chamber Volume ◽

Significant Difference ◽

Tilted Disc

Purpose. To evaluate anterior segment’s structures by Pentacam in patients with tilted disc syndrome (TDS).Methods. Group 1 included forty-six eyes of forty-six patients who have the TDS. Group 2 including forty-six eyes of forty-six cases was the control group which was equal to the study group in age, gender, and refraction. A complete ophthalmic examination was performed in both groups. All cases were evaluated by Pentacam. The axial length (AL) of eyes was measured by ultrasound. Quantitative data obtained from these measurements were compared between two groups.Results. There was no statistically significant difference for age, gender, axial length, and spherical equivalent measurements between two groups (p=0.625,p=0.830,p=0.234, andp=0.850). There was a statistically significant difference for central corneal thickness (CCT), corneal volume (CV), anterior chamber angle (ACA), and pupil size measurements between two groups (p=0.001,p=0.0001,p=0.003, andp=0.001). Also, there was no statistically significant difference for anterior chamber depth (ACD), anterior chamber volume (ACV), and lens thickness (LT) measurements between two groups (p=0.130,p=0.910, andp=0.057).Conclusion. We determined that CCT was thinner, CV was less, and ACA was narrower in patients with TDS. There are some changes in the anterior segment of the eyes with tilted disc.

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Effect of anterior chamber depth on the choice of intraocular lens calculation formula in patients with normal axial length

Middle East African Journal of Ophthalmology ◽

10.4103/0974-9233.142266 ◽

2014 ◽

Vol 21 (4) ◽

pp. 307 ◽

Cited By ~ 7

Author(s):

Hassan Hashemi ◽

Mehdi Khabazkhoob ◽

Farhad Rezvan ◽

Akbar Fotouhi ◽

Soheila Asgari ◽

...

Keyword(s):

Anterior Chamber ◽

Intraocular Lens ◽

Axial Length ◽

Anterior Chamber Depth ◽

Calculation Formula ◽

Intraocular Lens Calculation

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Progress in Modern Cataract Surgery – New Steps and Algorithms for Precise Measuring and Intraocular-lens Calculations

European Ophthalmic Review ◽

10.17925/eor.2017.11.02.95 ◽

2017 ◽

Vol 11 (02) ◽

pp. 95

Author(s):

Fritz H Hengerer ◽

Gerd U Auffarth ◽

Ina Conrad-Hengerer ◽

◽

...

Keyword(s):

Cataract Surgery ◽

Anterior Chamber ◽

Intraocular Lens ◽

Axial Length ◽

Refractive Surgery ◽

Anterior Chamber Depth ◽

Corneal Surface ◽

Intraocular Lens Calculations ◽

Target Refraction ◽

Intraocular Lens Calculation

In standard cataract surgery, one of the major goals is to reach target refraction. Based on keratometry measurements, axial length and anterior chamber depth, most of the intraocular lens calculation formulae are suitable to achieve this aim. Further evaluation of corneal refractive parameters like anterior and posterior corneal surface by Scheimpflug devices led to a significant enhancement of precision in astigmatic and post-refractive surgery cases.

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Parameters of Capsulorrhexis and Intraocular Lens Decentration After Femtosecond and Manual Capsulotomies in High Myopic Patients With Cataracts

Frontiers in Medicine ◽

10.3389/fmed.2021.640269 ◽

2021 ◽

Vol 8 ◽

Author(s):

Yanan Zhu ◽

Kexin Shi ◽

Ke Yao ◽

Yuyan Wang ◽

Sifan Zheng ◽

...

Keyword(s):

Femtosecond Laser ◽

Anterior Chamber ◽

Intraocular Lens ◽

Intraoperative Complications ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Rank Correlation ◽

Chi Square ◽

Significant Difference ◽

Intraocular Lens Decentration

Purpose: To compare the parameters of capsulorrhexis and intraocular lens decentration after femtosecond laser capsulotomy and manual continuous curvilinear capsulorrhexis in high myopic patients with cataracts.Methods: This is a prospective consecutive non-randomized comparative cohort study. Selected patients with axial length > 26.0 mm were divided into femtosecond laser capsulotomy (FS) group and manual continuous curvilinear capsulorrhexis (CCC) group. Five experienced phacoemulsification surgeons conducted all surgeries. Intraoperative complications and post-operative anterior segment photography were recorded. Intraocular lens decentration, area of capsulorrhexis, circularity, and capsule overlap were measured at 1 week, 1 month, and 2 years after surgery. Between group differences of parameters were determined with independent-sample t-test or the Mann–Whitney U-test, analysis of variance test, Pearson chi-square test, and Spearman rank correlation test.Results: The study included 142 eyes (108 patients), 68 eyes in the FS group, and 74 eyes in the CCC group. At 1 week, 1 month, and 2 years after surgery, the area of capsulorrhexis in the CCC group was significantly larger than in the FS group (P < 0.05), while no significant difference was noted in circularity values. The complete overlap ratio in the FS group was significantly higher than that in the CCC group (P < 0.05) at each measured timepoint. Significant correlations were noted between the anterior chamber depth and the area of capsulorrhexis in the CCC group (R = 0.25, P = 0.04), but did not correlate in the FS group (P > 0.05). In patients with an anterior chamber depth >3 mm, the capsule-intraocular lens (IOL) overlap of the CCC group was less than that of the FS group at all measured timepoints after surgery (P < 0.05). Meanwhile, the IOL decentration in the CCC group was significantly greater than that of the FS group in those patients at 2 years after surgery (P < 0.05).Conclusion: In high myopic patients with cataracts, with anterior chamber depth more than 3 mm, femtosecond laser capsulotomy can achieve better capsulorrhexis sizing and centering. Due to more precise capsulotomy and a better capsule-IOL overlap in the FS group, femtosecond laser capsulotomy resulted in better long-term centration of the IOL.

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