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

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.

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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.

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Intraocular Pressure Spikes after Aflibercept Intravitreal Injections

Ophthalmologica ◽

10.1159/000446878 ◽

2016 ◽

Vol 236 (1) ◽

pp. 43-47 ◽

Cited By ~ 10

Author(s):

Hussam El Chehab ◽

Emilie Agard ◽

Aurélie Russo ◽

Ygal Boujnah ◽

Corinne Dot

Keyword(s):

Intraocular Pressure ◽

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Angle Closure ◽

Iridocorneal Angle ◽

Chamber Volume ◽

Short Period ◽

Anterior Chamber Volume ◽

Acute Increase

The objective of this study was to assess the intraocular pressure (IOP) as well as the anatomical modifications of the anterior segment following an aflibercept injection. Patients underwent an aflibercept intravitreal injection (IVI) (0.05 ml) with a 30.5-gauge needle and an antireflux system. IOP was assessed before injection (T0), immediately after (T1), and 5 min (T5), 15 min (T15), and 45 min (T45) after the IVI. Before the IVI and immediately after the T1 measurement, a PENTACAM® acquisition was used to evaluate the anterior chamber parameters (anterior chamber volume, depth and measure of the iridocorneal angle). At T0, IOP was 12.9 ± 1.3 mm Hg. IOP significantly increased after IVI (42.7 ± 3 mm Hg, p < 0.001). IOP returned to baseline at T45 (13.0 ± 1.2 mm Hg, p = 0.877). Anterior chamber volume decreased after IVI (160.6 vs. 168.3 mm3, p = 0.002). No significant changes were found for iridocorneal angle and anterior chamber depth. Aflibercept IVI causes an acute increase in IOP over a short period without iridocorneal angle closure.

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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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Evaluation the Acute Effects of Hyperbaric Oxygen Therapy on Eye Anterior Segment Morphology and on İntraocular Pressure

10.21203/rs.3.rs-528769/v1 ◽

2021 ◽

Author(s):

Fatih Akıncı ◽

Abdullah Arslan ◽

Muammer Özcimen

Keyword(s):

Intraocular Pressure ◽

Anterior Chamber ◽

Hyperbaric Oxygen ◽

Hyperbaric Oxygen Therapy ◽

Central Corneal Thickness ◽

Oxygen Therapy ◽

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Iridocorneal Angle

Abstract Purpose: In this study the acute effects of 1 session of hyperbaric oxygen therapy on eye anterior segment morphology and on intraocular pressure was evaluated.Materials and methods: 30 patients taking hyperbaric oxygen therapy for different indications were included in this prospective study. Only the right eye per patient was included in the study. The refractive errors were measured with autorefractometry, intraocular pressures were measured with pneumatic tonometry; anterior segment parameters pachymetry, keratometry, anterior chamber depth and iridocorneal angle values were measured with corneal topography prior to and 24 hours after 1 session of hyperbaric oxygen therapy.Results: In this study 30 eyes from a total of 30 patients were evaluated; 19 men (% 64) and 11 women (% 36). Median age was 44.33 ±16.12 (Age range 18-80 years). Mean intraocular pressure was 13.7 ±4,16 mmHg (milimetermercuries), mean central corneal thickness was 531.9 ±28.24 μm, mean anterior chamber depth was 3.30 ±0.375 mm, mean iridocorneal angle value was 35.3± 6.61 degrees before hyperbaric oxygen therapy. The mean intraocular pressure was 12.66±4,54 mmHg, mean central corneal thickness was 529.43± 26.68 μm, mean anterior chamber depth was 3.28±0.372 mm, mean iridocorneal angle value was 34.5±6.42 degrees after HBOT. A statistically significant decrease in these values were recorded. No statistically significant changes were found in spheric equivalent and keratometry values of the patients before and after HBOT.Conclusions: After one session of HBOT a decrease in intraocular pressure, central corneal thickness, anterior chamber depth and iridocorneal angles of patients were observed; keratometry and spheric equivalent values remained unchanged. More studies are needed in order to use the effects of HBOT on anterior segment morphology and on intraocular pressure for situations like glaucoma, corneal edema etc.

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Preoperative Anatomy Parameters in Implantable Collamer Lenses

10.21203/rs.3.rs-968382/v1 ◽

2021 ◽

Author(s):

Yanzhen Xue ◽

Yonghong Guo ◽

Ruibo Zhao

Keyword(s):

Regression Analysis ◽

Linear Regression ◽

Anterior Chamber ◽

Linear Regression Analysis ◽

Corneal Thickness ◽

Intraclass Correlation ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Case Series ◽

Significant Difference

Abstract Purpose: To determine patient preoperative anatomical features and the parameters of implantable collamer lenses (ICLs) relevant in explaining vault variability.Setting: Ophthalmology Xi’an Aier Gucheng Eye hospital , Xi’an China.Design: Retrospective case series.Methods:This study comprised 88 eyes of 45 patients implanted with myopic or toric ICLs between May 2021 and August 2021.Pentacam imaging was used for assessing white-to-white (WTW) diameter, central keratometry, anterior chamber depth(ACD), central corneal thickness and vault. Anterior-segment optical coherence tomography（AS-OCT） was used to measure the horizontal anterior chamber angle distance (ATA). Ultrasound biomicroscopy (UBM) was used to measure horizontal and vertical sulcus to sulcus(vSTS). According to different ACD,we divide ACD into shallow group(2.8 to 3.2 mm),medium group(3.2 to 3.5 mm),and deep group(＞3.5mm).Results: Linear regression analysis found significant correlation between WTW diameters and ATA diameters( y= 0.9605x+0.1491,R² = 0.9148),with a coefficient of determinant of 0.9148 (P＜0.01). Linear regression analysis found significant correlation between hSTS and vSTS（y=0.9855x-0.0178,R²=0.1979）,with a coefficient of determinant of 0.1979 (P＜0.01). WTW diameters showed statistically significant difference in shallow and medium ACD (t=-3.28,P＜0.01 ), significant difference in shallow and deep ACD (t=-4.69,P＜0.01 ),there was no correlation in medium and deep ACD(t=-1.41,P＞0.05 ). There was a statistically significant correlation between WTW diameters and hSTS diameters when the ACD was less than 3.5 mm (t=-0.451, P=0.000) (t=1.406, P=0.026),but weak correlation when the ACD was bigger than 3.5 mm(t=1.594, P=0.051). ATA and WTW with a mean difference close to zero(-0.66 mm). Despite the relatively high correlation (intraclass correlation co-efficient =0.689), the range of agreement is quite broad (1.33 mm).Conclusions:ATA measured with AS-OCT can not be used interchangeably with WTW obtained with Pentacam. WTW diameters and hSTS diameters have a statistically significant correlation when the ACD was less than 3.5 mm. WTW, ATA, hSTS and vSTS all should be considered during design the size of lens and regulating the vault after surgery.

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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.

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

Journal of Ophthalmology ◽

10.1155/2018/5926508 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5

Author(s):

Mustafa Doğan ◽

Mehmet Cem Sabaner ◽

Mehmet Akif Erol

Keyword(s):

Pupil Diameter ◽

Corneal Thickness ◽

Anterior Segment ◽

Sodium Fluorescein ◽

Chamber Volume ◽

Anterior Chamber Volume ◽

Mixture Group ◽

The Mean ◽

Anterior Segment Parameters ◽

15Th Minute

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.

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Association of anterior segment parameters and 5-year incident narrow angles: findings from an older Chinese population

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2020-315852 ◽

2020 ◽

pp. bjophthalmol-2020-315852

Author(s):

Yu Jiang ◽

Wei Wang ◽

Lanhua Wang ◽

Mingguang He

Keyword(s):

Anterior Chamber ◽

Multiple Logistic Regression Analysis ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Narrow Angle ◽

Chamber Volume ◽

Anterior Chamber Volume ◽

Oct Imaging ◽

Older Chinese ◽

Analysis Models

PurposeTo assess the association of anterior segment optical coherence tomography (AS-OCT) parameters and 5-year incident narrow angle in China.MethodsThis was a prospective cohort study of people aged 50 and older residing in Liwan District, Guangzhou, China. Random clustering sampling was used to identify adults aged 50 years and older in Liwan District, Guangzhou. In 2008 and 2013, this study was repeated and added AS-OCT imaging under dark and light conditions. Customised software (ZAAP) was used to analyse horizontal AS-OCT scans. Angle opening distance (AOD), trabecular iris space area (TISA), anterior chamber volume (ACV) and maximal iris thickness (ITM) were measured. Multiple logistic regression analysis models were used to investigate the associations of the final angle status with baseline AS-OCT parameters. ORs and 95% CIs were calculated.ResultsOf the 220 subjects with eligible AS-OCT images and gonioscopic results in 2008, the response rate was 77.3%. A total of 27 (15.9%) subjects developed narrow angles and 143 (84.1%) had open angles on gonioscopy in 2013. Subjects developed narrow angles had greater spherical equivalent and shallower anterior chamber depth, smaller angle parameters, thicker IT750 and ITM, smaller anterior chamber parameters, greater lens vault, and smaller dynamic parameters (ΔITM, ΔACA, ΔACV) at baseline. After adjusting confounders, the predictors of incident narrow angles included smaller AOD750, TISA750, ΔACA and greater ITM, ΔIarea.ConclusionsIncident narrow angles were associated with smaller anterior ocular dimensions, thicker iris and smaller light-to-dark changes at baseline. These findings can help in early diagnosis in this population.

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Pupil Size Associated with the Largest Iris Volume in Normal Chinese Eyes

Journal of Ophthalmology ◽

10.1155/2018/8058951 ◽

2018 ◽

Vol 2018 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Shuning Li ◽

Jing Jiang ◽

Yiquan Yang ◽

Gewei Wu ◽

Shi-Ming Li ◽

...

Keyword(s):

Anterior Chamber ◽

Pupil Size ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Quadratic Equation ◽

Swept Source ◽

Chamber Volume ◽

Anterior Chamber Volume ◽

The Relationship ◽

Pupillary Size

Background. To determine the range of pupil size that has the largest iris volume in normal eyes. Methods. 31 healthy adult Chinese volunteers underwent swept-source anterior segment OCT examination in both eyes. Pilocarpine 1% was instilled in a randomly selected eye (eye with induced miosis (ME)) of each participant to obtain iris volume (IV) measurements over a range of pupil sizes. OCT was performed prior to and one hour after pilocarpine in both ME and fellow eye (FE). Iris volume (IV), anterior chamber volume (ACV), anterior chamber depth (ACD), and pupil size (PS) were recorded. A scatter plot was used to depict the association between each pupil size and IV. Results. The pupillary sizes for which IV was recorded in ME and FE ranged from 1.161 mm to 6.665 mm. The mean IV increased with miosis in both ME and FE; in 13 eyes, IV decreased with a decrease in pupillary size. PS between 3.812 and 6.665 mm was associated with an increase in IV, while PS between 3.159 and 5.54 mm was associated with a decrease. The relationship between PS and IV was in the shape of a downward parabola and was modeled using a quadratic equation (y = −1.3121x2 + 8.8429x + 16.423, R2 = 0.26886). The largest IV occurred at PS between 3 and 4 mm. Conclusions. The relationship between PS and IV in this study was in the shape of a downward parabola. The largest IV was recorded at a pupillary size between 3 and 4 mm. This trial is registered with ChiCTR-ROC-17013572.

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