Distribution and internal correlations of corneal astigmatism in cataract patients

AbstractThe aim of the study is to explore the distribution patterns and internal correlations of the morphological parameters of the cornea in patients with age-related cataract. The Pentacam HR was used to measure anterior corneal astigmatism (ACA), posterior corneal astigmatism (PCA), total corneal astigmatism (TCA) and keratometric corneal astigmatism (KCA). With age, the proportion of with-the-rule (WTR) ACA decreased from 65.31% to 23.63%, while the against-the-rule (ATR) ACA increased from 26.53% to 56.20%. PCA exceeded 0.50 D in 9.14% of eyes, while 76.35% of them were ATR. The magnitude of ACA was positively correlated with PCA in the whole sample, with a more significant correlation in WTR eyes (sr = 0.349, P < 0.001). The vector summation effect of PCA to ACA changed from compensation to augmentation with aging. In 57.53% of WTR eyes, KCA was overestimated by an average of 0.21 ± 0.17 D, while it was underestimated by 0.38 ± 0.27 D in 87.62% of ATR eyes. In conclusion, among age-related cataract patients, ACA and TCA gradually shifted from WTR to ATR with aging, while most PCA remained as ATR. Ignoring the age-related changes and real PCA might cause overestimation of WTR astigmatism and underestimation of ATR astigmatism.

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Age-related Changes in Anterior, Posterior Corneal Astigmatism in a Korean Population

Journal of the Korean Ophthalmological Society ◽

10.3341/jkos.2017.58.8.911 ◽

2017 ◽

Vol 58 (8) ◽

pp. 911

Author(s):

Yoon Seob Sim ◽

Soon Won Yang ◽

Yu Li Park ◽

Kyung Sun Na ◽

Hyun Seung Kim

Keyword(s):

Corneal Astigmatism ◽

Korean Population ◽

Age Related ◽

Anterior Posterior ◽

Age Related Changes ◽

Posterior Corneal Astigmatism

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Age-Related Changes in Anterior, Posterior, and Total Corneal Astigmatism

Journal of Refractive Surgery ◽

10.3928/1081597x-20140218-01 ◽

2014 ◽

Vol 30 (3) ◽

pp. 192-197 ◽

Cited By ~ 34

Author(s):

Yuta Ueno ◽

Takahiro Hiraoka ◽

Simone Beheregaray ◽

Maki Miyazaki ◽

Mutsuko Ito ◽

...

Keyword(s):

Corneal Astigmatism ◽

Age Related ◽

Anterior Posterior ◽

Age Related Changes ◽

Total Corneal Astigmatism

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Gender-differences in age-related changes of corneal astigmatism in Korean cataract patients

BMC Ophthalmology ◽

10.1186/s12886-018-1001-1 ◽

2019 ◽

Vol 19 (1) ◽

Cited By ~ 1

Author(s):

Hyojin Kim ◽

Youngju An ◽

Choun-Ki Joo

Keyword(s):

Gender Differences ◽

Corneal Astigmatism ◽

Age Related ◽

Cataract Patients ◽

Age Related Changes

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Effect of 1.8-mm steep-axis clear corneal incision on the posterior corneal astigmatism in candidates for toric IOL implantation

10.21203/rs.2.24131/v2 ◽

2020 ◽

Author(s):

Xi Li ◽

Xiang Chen ◽

Suhong He ◽

Wen Xu

Keyword(s):

Corneal Astigmatism ◽

Corneal Incision ◽

Toric Iol ◽

Iol Implantation ◽

Clear Corneal Incision ◽

Paired T Test ◽

Anterior Posterior ◽

Anterior Corneal Astigmatism ◽

Posterior Corneal Astigmatism ◽

Total Corneal Astigmatism

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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Faculty Opinions recommendation of Contribution of posterior corneal astigmatism to total corneal astigmatism.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.717968306.793471314 ◽

2013 ◽

Author(s):

William Myers

Keyword(s):

Corneal Astigmatism ◽

Posterior Corneal Astigmatism ◽

Total Corneal Astigmatism

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Does pterygium morphology affect corneal astigmatism?

Therapeutic Advances in Ophthalmology ◽

10.1177/25158414211030423 ◽

2021 ◽

Vol 13 ◽

pp. 251584142110304

Author(s):

Emine Doğan ◽

Burçin Çakır ◽

Nilgün Aksoy ◽

Elif Köse ◽

Gürsoy Alagöz

Keyword(s):

Anterior Segment ◽

Clinical Information ◽

Corneal Astigmatism ◽

Continuous Group ◽

Optic Coherence Tomography ◽

Morphological Pattern ◽

Horizontal Length ◽

The Mean ◽

Anterior Corneal Astigmatism ◽

Posterior Corneal Astigmatism

Purpose: The purpose of this study was to evaluate the correlation between corneal astigmatism and the morphology of pterygium with anterior segment optic coherence tomography (AS-OCT). Material and Methods: The size of pterygium (horizontal length, vertical width) was measured manually; pterygium area and percentage extension of the pterygium onto the cornea were calculated. Anterior and posterior corneal astigmatism, Sim K, K1, K2 were measured using a dual Scheimpflug analyzer. Morphological patterns of the pterygium analyzed with AS-OCT were determined according to the extension of the pterygium apex below the corneal epithelium. Two tomographic patterns were identified: continuous and nodular. Correlation between anterior corneal astigmatism and pterygium size, percentage extension of the pterygium, and morphological pattern of the pterygium was analyzed. Results: The mean ages of the 47 patients were 49.4 ± 16.6 (22–80) years. Mean horizontal pterygium length, vertical width, pterygium area, and percentage extension of the pterygium were 2.8 ± 1.2 mm, 4.8 ± 1.6 mm, 7.42 ± 5.6 mm2 and 24.5 ± 10.4%, respectively. Mean anterior corneal astigmatism was 2.3 ± 2.3 D and simulated keratometry was 43.4 ± 2.02 D. In terms of the morphological pattern of the pterygium, 24 eyes had continuous, 23 eyes had a nodular pattern and the median (interquartile range) anterior corneal astigmatism was 1.87 (1.01–3.80) and 1.22 D (0.58–2.35), respectively ( p = 0.102). Other topographic and pterygium size parameters were similar between groups. Analyzing the correlations in groups separately, a positive moderate statistically significant correlation was present between vertical width, percentage extension, pterygium area, and anterior corneal astigmatism in both continuous and nodular groups. Conclusions: Although not statistically significant, anterior corneal astigmatism was higher in continuous group. Using AS-OCT to standardize the morphology of pterygium could provide additional clinical information.

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Age-related changes in with-the-rule and oblique corneal astigmatism

Acta Ophthalmologica ◽

10.1111/aos.13683 ◽

2018 ◽

Vol 96 (6) ◽

pp. 600-606 ◽

Cited By ~ 6

Author(s):

Kristian Naeser ◽

Giacomo Savini ◽

Jesper Flethøj Bregnhøj

Keyword(s):

Corneal Astigmatism ◽

Age Related ◽

Age Related Changes

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Power Vector Analysis of Corneal Astigmatism among Chinese over Fifty Years Old: a retrospective cross-sectional study

10.21203/rs.3.rs-17216/v1 ◽

2020 ◽

Author(s):

Yilin Pang ◽

Xiaoguang Cao ◽

Xianru Hou ◽

Li Yuan ◽

Yongzhen Bao

Keyword(s):

Axial Length ◽

Linear Trend ◽

Linear Regression Analysis ◽

Corneal Astigmatism ◽

Vector Analysis ◽

Cross Sectional ◽

Age Related ◽

Relationship Of ◽

The Relationship ◽

Cataract Patients

Abstract Background: To investigate the relationship between corneal astigmatism and age, axial length (AL) among Chinese over fifty years old. Methods: This study enrolled 1,082 right eyes of age-related cataract patients over 50 years old in the clinic of Peking University People’s Hospital, Beijing, China. Axial length, magnitude and meridian of anterior corneal astigmatism were measured by IOLMaster. Restricted cubic splines and Spearman rank correlation coefficients were used to investigate the relationship of the magnitude of cornea astigmatism to age and AL. Power vector analysis method and linear regression analysis were used to assess the relationship of the meridian of astigmatism to age and AL. Results: For this study , mean age, AL, and corneal astigmatism value were 72.45 ±9.28 years, 23.90±1.93mm, and 1.12±0.74D, respectively. The magnitude of corneal astigmatism was 0.75D or higher in 63.8% eyes. The magnitude of corneal astigmatism increased with age after 65 years old. This correlation was statistically significant when AL was between 22.00mm and 26.00mm. The vector value in J 0 was inversely correlated with age. The mean vector value change from with-the-rule (WTR) to against-the-rule (ATR) corneal astigmatism was 0.22D/10 years during 50-65 years old and 0.15D/10 years during 65-85 years old, and was 0.22D/10 years in male and 0.12D/10 years in female, respectively. Conclusions: A large proportion of elderly Chinese cataract patients over 50 years old have corneal astigmatism more than 0.75D . There was a non-linear trend from WTR astigmatism towards ATR astigmatism with age, which was more obvious in elder age and in male. When AL is between 22.00mm and 26.00mm, the magnitude of corneal astigmatism increases with age after 65 years old.

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