Effect of Proparacaine 0.375%-Sodium Fluorescein 0.25% Eye Drop Mixture and Fluorescein Strip on Anterior Segment Parameters

Purpose. To determine the effect of proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture and fluorescein strip on anterior segment parameters commonly used in routine ophthalmology practice. Methods. 115 healthy volunteers without any systemic or ocular disease were divided into two groups. 57 volunteers were in the proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture group, and 58 volunteers were in the fluorescein strip group. Measurements (CCT (central corneal thickness), topographic pupil diameter, AD (aqueous depth), ACV (anterior chamber volume), ICA (iridocorneal angle), LLD (limbus-limbus distance), and CV (corneal volume)) were taken before and at 1, 5, 15, and 30 minutes after application. Results. 59 (51.3%) participants were female, and 56 (48.7%) were male. The mean age of the drop application group was 26.88 ± 8.03, and the mean age of the strip application group was 26.33 ± 7.28. The mean CCT was 556 ± 32 μm before drop application and 569 ± 30 μm in the 1st minute, 560 ± 32 μm in the 5th minute, and 559 ± 31 μm in the 15th minute. The change was statistically significant (p<0.001, p=0.005, and p=0.013, resp.). Before the strip application, mean CCT was 552 ± 36 μm, while it increased to 556 ± 36 μm at the 1st minute, and this change was statistically significant (p=0.002). The mean CV before dropping was 59.29 ± 3.53 mm3 and 60.62 ± 3.53 mm3 at the 1st minute and 59.66 ± 3.70 mm3 at the 5th minute, which was statistically significant (p<0.001 and p=0.034). Mean topographic pupil diameters at the 1st, 5th, 15th, and 30th minute after application of drops and strips were not significantly changed compared to the preapplication values in the AD, ACV, ICA, and LLD measurements. Conclusions. Proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture and fluorescein strip application lead to a temporary change in CCT and CV of the anterior segment parameters. Anterior segment measurements with the Scheimpflug camera have to be done before topical fluorescein application.

Download Full-text

The Effect of Axial Length Elongation on Corneal Biomechanical Property

Frontiers in Bioengineering and Biotechnology ◽

10.3389/fbioe.2021.777239 ◽

2021 ◽

Vol 9 ◽

Author(s):

Guihua Liu ◽

Hua Rong ◽

Ping Zhang ◽

Yu Xue ◽

Bei Du ◽

...

Keyword(s):

Axial Length ◽

Corneal Thickness ◽

Growth Patterns ◽

Biomechanical Property ◽

Corneal Tissue ◽

Biomechanical Parameter ◽

Chamber Volume ◽

Anterior Chamber Volume ◽

Kolmogorov Smirnov ◽

The Mean

Background: To investigate the correlation between the corneal biomechanical parameter stress-strain index (SSI) and axial length (AL) in moderately elongated eye (MEE) and severely elongated eye (SEE).Methods: This study included 117 eyes from 117 participants. Among them, 59 (50.4%) had MEE (AL<26 mm) and 58 (49.6%) had SEE (AL≥26 mm). AL was measured using Lenstar LS-900, and central corneal thickness (CCT) and anterior chamber volume (ACV) were measured using Pentacam. SSI was measured via corneal visualisation Scheimpflug technology (Corvis ST). Kolmogorov-Smirnov test, Student’s t-test, and Pearson and partial correlation analyses were used for statistical analyses.Results: The mean (±SD) SSI was 1.08 ± 0.15 in the MEE group and 0.92 ± 0.13 in the SEE group (p < 0.01). SSI was positively correlated with age (MEE: r = 0.326, p < 0.05; SEE: r = 0.298, p < 0.05) in both groups; it was negatively correlated with AL (r = −0.476, p < 0.001) in the MEE group but not in the SEE group (p > 0.05). CCT was negatively correlated with AL (r = −0.289, p < 0.05) and ACV positively correlated with AL (r = 0.444, p < 0.001) in the MEE group. Neither CCT nor ACV was correlated with AL (p > 0.05) in the SEE group.Conclusion: Corneal biomechanical parameter SSI, which represents the stiffness of corneal tissue, was lower in the SEE group than in the MEE group. When analyzed separately, SSI was negatively correlated with AL in the MEE group, but not in the SEE group, which may provide insight into different ocular growth patterns between lower myopia and higher myopia.

Download Full-text

Changes in Anterior Segment Morphology of Iris Bombe before and after Laser Peripheral Iridotomy in Patients with Uveitic Secondary Glaucoma

Journal of Ophthalmology ◽

10.1155/2016/8496201 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Wakako Ikegawa ◽

Takashi Suzuki ◽

Koji Namiguchi ◽

Shiro Mizoue ◽

Atsushi Shiraishi ◽

...

Keyword(s):

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Anterior Chamber Angle ◽

Laser Peripheral Iridotomy ◽

Chamber Volume ◽

Anterior Chamber Volume ◽

Before And After ◽

The Mean ◽

Peripheral Iridotomy

Purpose. To quantify changes in anterior segment (AS) parameters after laser peripheral iridotomy (LPI) using AS-optical coherence tomography (OCT) of iris bombe. Method. AS images of eight eyes were captured before and after iris bombe and more than 2 weeks after LPI (post-LPI) using AS-OCT. We compared the following AS parameters: anterior chamber depth (ACD), anterior chamber volume (ACV), iris curvature (IC), iris thickness at 500 μm from the scleral spur (IT-1) in the middle between the iris root and pupillary margin (IT-2) and 500 μm from the pupillary margin (IT-3) to the anterior chamber angle (ACA) (angle opening distance [AOD750]), and trabecular iris space area. Results. Mean IT-1 and IT-3, but not IT-2, were lower after iris bombe (IT-1, P=0.001; IT-2, P=0.081; and IT-3, P=0.001). There were no significant differences between ACD at pre-LPI and before iris bombe (P=0.096). The mean ACV and AOD750 of iris bombe increased at post-LPI (ACV, P<0.01, and AOD750, P<0.05). The mean IT-1, IT-2, and IT-3 increased at post-LPI (all, P≤0.01). IC decreased at post-LPI (P<0.001), and ACD at post-LPI did not change. Conclusions. The iris extends and becomes thinner during iris bombe. LPI during bombe decreases the IC and increases the ACV and ACA.

Download Full-text

Genetic Covariance Between Central Corneal Thickness and Anterior Chamber Volume: A Hungarian Twin Study

Twin Research and Human Genetics ◽

10.1017/thg.2014.54 ◽

2014 ◽

Vol 17 (5) ◽

pp. 397-404 ◽

Cited By ~ 2

Author(s):

Georgina Zsofia Toth ◽

Adel Racz ◽

Adam Domonkos Tarnoki ◽

David Laszlo Tarnoki ◽

Zita Szekelyhidi ◽

...

Keyword(s):

Anterior Chamber ◽

Central Corneal Thickness ◽

Genetic Factors ◽

Corneal Thickness ◽

Anterior Segment ◽

Angle Closure ◽

Genetic Covariance ◽

Chamber Volume ◽

Anterior Chamber Volume ◽

High Heritability

Background: Few, and inconsistent, studies have showed high heritability of some parameters of the anterior segment of the eye; however, no heritability of anterior chamber volume (ACV) has been reported, and no study has been performed to investigate the correlation between the ACV and central corneal thickness (CCT). Methods: Anterior segment measurements (Pentacam, Oculus) were obtained from 220 eyes of 110 adult Hungarian twins (41 monozygotic and 14 same-sex dizygotic pairs; 80% women; age 48.6 ± 15.5 years) obtained from the Hungarian Twin Registry. Results: Age- and sex-adjusted heritability of ACV was 85% (bootstrapped 95% confidence interval; CI: 69% to 93%), and 88% for CCT (CI: 79% to 95%). Common environmental effects had no influence, and unshared environmental factors were responsible for 12% and 15% of the variance, respectively. The correlation between ACV and CCT was negative and significant (rph = −0.35, p < .05), and genetic factors accounted for the covariance significantly (0.934; CI: 0.418, 1.061) based on the bivariate Cholesky decomposition model. Conclusion: These findings support the high heritability of ACV and central corneal thickness, and a strong genetic covariance between them, which underscores the importance of identification of the specific genetic factors and the family risk-based screening of disorders related to these variables, such as open-angle and also angle closure glaucoma and corneal endothelial alterations.

Download Full-text

Repeatability of Ocular Measurements with a Dual-Scheimpflug Analyzer in Healthy Eyes

BioMed Research International ◽

10.1155/2014/808646 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 4

Author(s):

Carmen Lopez de la Fuente ◽

Ana Sanchez-Cano ◽

Francisco Segura ◽

Lorena Fuentes-Broto ◽

Isabel Pinilla

Keyword(s):

Anterior Chamber ◽

Corneal Thickness ◽

Intraclass Correlation ◽

Anterior Segment ◽

Clinical Results ◽

Complete Characterization ◽

Repeated Measurements ◽

Iridocorneal Angle ◽

Chamber Volume ◽

Anterior Chamber Volume

Purpose. To assess the repeatability of the Galilei dual Scheimpflug analyzer (GDSA) in anterior segment examination.Methods. Fifty-two eyes from 52 healthy volunteers were prospectively and consecutively recruited. Anatomic, axial, refractive, and instantaneous parameters were measured with GDSA to provide a complete characterization of the anterior segment. Repeatability was assessed calculating intraclass correlation coefficient (ICC), and coefficient of variation (COV).Results. Correlation among repeated measurements showed almost perfect reliability (ICC > 0.81) for all parameters except thinnest central corneal thickness (CCT) (0.78), corneal thickness average out (0.79), and posterior axial curvature average out (0.60). Repeatability was excellent (COV<10%) for all parameters except anterior chamber volume and, superior iridocorneal angle and eccentricities. In these last three parameters, repeatability limits were excessively high compared to the mean.Conclusions. GDSA in healthy young persons had an almost perfect correlation in measuring anatomic, axial, instantaneous, and refractive parameters with greater variability for peripheral terms. Repeatability of anatomical parameters like pachymetry, anterior chamber, or iridocorneal angle and eccentricity were limited. In healthy young persons, the other evaluated parameters had very good repeatability and their limits of agreement showed excellent clinical results for this device.

Download Full-text

Analysis of Anterior Segment Parameters and Wavefront Aberrations of the Myopic Eyes Using Two Scheimpflug-based Devices: The Pentacam vs Sirius

10.21203/rs.3.rs-298563/v1 ◽

2021 ◽

Author(s):

Ali Mirzajani ◽

Rasoul Amini Vishteh ◽

Rezvan Masroor

Keyword(s):

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Corneal Surface ◽

Mean Values ◽

Wavefront Aberrations ◽

Measurement Results ◽

The Mean ◽

Anterior Segment Parameters ◽

Corneal Tomography

Abstract Purpose: To measurements, comparisons, and agreement of the anterior segment parameters and wavefront aberrations of the myopic eyes through the Pentacam and Sirius tomography systems. Methods: The Pentacam and Sirius were used to measure the corneal anterior segment tomography and wavefront aberrations of the myopic eyes with a mean age of 25.66±3.77 (range from 19 to 31 years).Various parameters such as the anterior keratometric reading of the flattest meridian K1, anterior K2, thinnest corneal thickness, corneal surface asphericity Q-value, anterior chamber depth, Root mean square (RMS) of higher-order aberrations, RMS of lower-order aberrations, and RMS of total aberrations were analyzed. Also, the agreement between the Pentacam and Sirius was assessed by calculating 95% limits of agreement and plotting the Bland–Altman graphs.Results: One eye of 99 myopic subjects (49 men, 50 women) aged 19 to 31 years was randomized and evaluated. All measured parameters of the Pentacam and Sirius tomography systems were statistically significant (p<0.001) in comparison with each other expect the mean values of K1, K2, and thinnest corneal thickness (p>0.05). The thinnest corneal thickness findings showed the poorest agreement (95 %limit of agreement from -8.71 to 24.21) and the greatest difference (mean difference: 7.75).Conclusions: The differences between the gained measurement results of the devices suggests that they should not be used interchangeably for corneal tomography imaging in clinical practice and surgery decision.

Download Full-text

Measurement of and Factors Associated with the Anterior Chamber Volume in Healthy Chinese Adults

Journal of Ophthalmology ◽

10.1155/2017/6762047 ◽

2017 ◽

Vol 2017 ◽

pp. 1-6 ◽

Cited By ~ 6

Author(s):

Yuan Zong ◽

Qian Xu ◽

Chunhui Jiang ◽

Haohao Zhu ◽

Jian Yu ◽

...

Keyword(s):

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Chinese Adults ◽

Factors Associated ◽

Chamber Volume ◽

Significant Difference ◽

Anterior Chamber Volume ◽

Anterior Segment Parameters ◽

Healthy Chinese

Purpose. To measure the anterior chamber volume (ACV) and determine factors associated with the ACV in healthy Chinese adults.Methods. In this cross-sectional study, we used swept-source optical coherence tomography (SS-OCT) to measure ACV and other anterior segment parameters. Factors associated with ACV were also determined.Results. A total of 313 healthy Chinese adults were enrolled. The anterior segment parameters, including ACV, could be measured by SS-OCT with excellent repeatability and reproducibility. There was a significant difference between the horizontal and vertical anterior chamber widths (ACW) (P<0.05), with a mean difference of 390 μm. The ACV (mean153.83±32.42 mm3) was correlated with most of the anterior segment parameters, especially anterior chamber depth (ACD), which accounted for about 85% of the variation of ACV. Most of the anterior segment parameters were significantly correlated with age, and the relative changes in ACV and ACD were greatest in subjects aged 41–50 years.Conclusion. ACV was correlated with most of the anterior segment parameters measured in this study, particularly ACD. The relatively large difference between horizontal and vertical ACW suggests that the ACV could and should be measured using multiple OCT scans.

Download Full-text

Evaluation of anterior chamber volume using Pentacam and anterior segment optical coherence tomography among normal subjects

Asian Journal of Ophthalmology ◽

10.35119/asjoo.v16i2.367 ◽

2018 ◽

Vol 16 (2) ◽

pp. 86-94

Author(s):

Vijaya Anandan ◽

Rekha Srinivasan ◽

Rashima Asokan ◽

Ronnie George

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Anterior Segment ◽

Normal Subjects ◽

Optical Coherence ◽

Cross Sectional ◽

Chamber Volume ◽

Anterior Chamber Volume ◽

Volume Measurements ◽

The Mean

Aim: To compare the anterior chamber volume measurements obtained with Pentacam and derived from anterior segment optical coherence tomography. Design: Cross-sectional study. Methods: We included normal subjects who underwent a comprehensive eye examination including refraction, keratometry, Goldmann applanation tonometry, gonioscopy, anterior segment optical coherence tomography (AS-OCT) (Carl Zeiss Meditec Inc.; Dublin, CA, USA) and Pentacam (Oculus Inc.; Lynnwood, WA, USA). Fifty scans were selected for Pentacam and 12 images were selected for calculation of anterior chamber volume. Only the right eye was considered for analysis. Results: One-hundred and nineteen eyes of 119 subjects were included for analysis. The mean age of the subjects was 42.58 ± 13.15 years, of which 74 were female and 45 were male. The mean anterior chamber volume measured using AS-OCT was 119.17 ± 26.56 mm3 and with Pentacam was 131.29 ± 34.26 mm3. The comparison of means between the two modalities was statistically significant (t = -8.857, Mean Difference (MD) = 12.11, 95% CI: (4.29, 19.95), p = 0.003). Bland-Altman plot showed poor agreement between the chamber volume measurements obtained by Pentacam and AS-OCT with MD of 12.1 mm3 (95 % CI: 41.4 to -17.1) and intra-class correlation between the two instruments was 0.94 (95% CI: 0.91, 0.96) (p < 0.0001). Conclusion: The anterior chamber volume can be measured using Pentacam as well as AS-OCT since these measurements were reliable. However, these measurements were not interchangeable due to poor levels of agreement.

Download Full-text

Correlation of Anterior Segment Parameters in Keratoconus Patients

International Journal of Keratoconus and Ectatic Corneal Diseases ◽

10.5005/jp-journals-10025-1017 ◽

2012 ◽

Vol 1 (2) ◽

pp. 87-91 ◽

Cited By ~ 1

Author(s):

Leonardo Torquetti

Keyword(s):

Pearson Correlation ◽

Corneal Thickness ◽

Anterior Segment ◽

Inverse Correlation ◽

Q Value ◽

Significant Difference ◽

Severe Group ◽

Corneal Asphericity ◽

The Mean ◽

Anterior Segment Parameters

ABSTRACT Purpose To evaluate the corneal asphericity, volume, thickness and keratometry and the correlation among these variables in keratoconus patients. Materials and methods A total of 1,071 eyes of 810 patients diagnosed with keratoconus were evaluated with a Pentacam (Oculus Optikgerate GmbH). Five groups were established according to the mean keratometry readings: Very mild [K < 44.0 diopters (D)], mild (K = 44.0-47.0D), moderate (K = 47.0-52.0D), severe (K = 52.0-60.0D) and very severe (K = 60.0 or higher). The following parameters were obtained: Anterior corneal asphericity (Q), corneal volume (CV) and thinnest corneal thickness (TCT). Results Sixty-six eyes had very mild keratoconus, 269 had mild keratoconus, 465 had moderate keratoconus, 233 had severe keratoconus and 38 had very severe keratoconus. As the severity of disease increases, there is an increment in K and CV values and reduction of Q and TCT. There was a statistically significant difference in values for all parameters, except the CV. The Pearson correlation index showed an inverse correlation between the degree of keratoconus and the asphericity (Q), i.e. the more severe the keratoconus the more negative the Q-value. Only in the very severe group there was no statistically significant correlation between K and Q. There was no correlation between severity of keratoconus and CV. There was an inverse correlation between keratoconus grade and TCT; the more advanced the disease the less the TCT value. Only in the very mild group there was no correlation between K and TCT. Conclusion The corneal asphericity and pachymetry are inversely correlated to keratometry in keratoconus patients. There is no correlation between CV and severity of keratoconus. How to cite this article Torquetti L, Ferrara G, Ferrara P. Correlation of Anterior Segment Parameters in Keratoconus Patients. Int J Kerat Ect Cor Dis 2012;1(2):87-91.

Download Full-text

Five-year changes in anterior segment parameters in an older population in urban southern China: the Liwan Eye Study

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2019-313827 ◽

2019 ◽

Vol 104 (4) ◽

pp. 582-587 ◽

Cited By ~ 1

Author(s):

Yu Jiang ◽

Decai Wang ◽

Wei Wang ◽

Feng Chen ◽

Lanhua Wang ◽

...

Keyword(s):

Anterior Chamber ◽

Pupil Diameter ◽

Southern China ◽

Anterior Segment ◽

Population Based ◽

Light Conditions ◽

Anterior Chamber Angle ◽

The Mean ◽

Angle Width

PurposeTo investigate the 5-year changes in static and dynamic anterior segment optical coherence tomography (AS-OCT) parameters and their predictors.MethodsThis was a prospective, population-based cohort study of people aged 50 years and older residing in the Liwan District, Guangzhou, China. Standardised AS-OCT scans were performed in November 2008 and November 2013 under dark and light conditions. Customised software was used to analyse horizontal AS-OCT images. Parameters in dark and measurements of light-to-dark changes were used for analyses.ResultsA total of 186 (71.8%) subjects underwent AS-OCT twice, 5 years apart and were included for analyses. The mean age in 2008 was 64.7±7.0 years, and 60.2% were women. The anterior chamber width (ACW) decreased from 11.74±0.44 mm in 2008 to 11.60±0.37 mm in 2013 (p=0.001). There was a trend towards a decrease in dynamic capacity (light-to-dark changes) in the anterior segment, with decreased iris thickness at 750 µm (ΔIT750), ΔACW, Δ anterior chamber area (ACA) and Δ pupil diameter at 5 years (all p<0.05). After adjusting for age and sex, the following baseline parameters were associated with a greater decrease rate in trabecular iris space area at 500 µm (TISA500) at 5 years: TISA500, IT750 and ACA in dark (p<0.001 for all).ConclusionsAnterior chamber angle width decreased and the amount of light-to-dark changes declined during 5-year follow-up. Subjects with greater height, wider angle width and thicker iris at baseline have greater angle narrowing at follow-up.

Download Full-text

Correlation between Central Corneal Thickness and Degree of Myopia among Malaysian Patients Undergoing Laser Keratorefractive Surgery

Journal of Advances in Medicine and Medical Research ◽

10.9734/jammr/2020/v32i2230705 ◽

2020 ◽

pp. 52-58

Author(s):

Sagili Chandrasekhara Reddy ◽

Mohd Mansor Shariff ◽

Aina Malindri Dasrilsyah

Keyword(s):

Optical Coherence Tomography ◽

Refractive Surgery ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Anterior Segment ◽

Military Hospital ◽

Moderate Degree ◽

Optical Coherence ◽

Corneal Refractive Surgery ◽

The Mean

Purpose: To determine the central corneal thickness in myopic adult patients scheduled for laser corneal refractive surgery and to explore its correlation with degree of refractive error. Materials and Methods: The case records of 130 myopic patients who underwent laser corneal refractive surgery in a military hospital over a period of two years were reviewed to determine the central corneal thickness. All patients had 6/6 vision with best correction, and did not have any other anterior segment or fundus diseases in both eyes. The central corneal thickness was measured with Visante Carl Zeiss anterior segment optical coherence tomography instrument. Results: Out of 130 patients, males were more (73, 56.2%); mean age of patients was 33.8 years (range 18-60 years) and majority were Malays (110, 84.6%). The spherical power of myopia ranged from – 0.5 to – 10.00 D, and the cylindrical power ranged from – 0.25 to – 3.25 D. The mean central corneal thickness of both eyes was 528.2 µm (range 331- 615 µm); in the mild degree of myopia (- 0.50 to - 2.00 D) 527.9 µm, moderate degree (- 2.25 to -5.00 D) 529.4 µm, and high degree (-5.25 to -11.00 D) 523.9 µm. Conclusion: The anterior segment optical coherence tomography provides noncontact, rapid, pachymetry mapping of the corneal thickness. In Malaysian patients, the mean central corneal thickness of both eyes in myopia was 528.1 µm (range 331- 615 µm). There was no correlation between the mean central corneal thickness and degree of myopia, different genders, age groups, ethnic groups and two eyes.

Download Full-text