Comparison of Slitlamp Optical Coherence Tomography and Scanning Peripheral Anterior Chamber Depth Analyzer to Evaluate Angle Closure in Asian Eyes

Abstract This study compared the test–retest variabilities and measurement agreement of anterior chamber angle (ACA) dimensions measured by two anterior segment swept-source optical coherence tomography (SS-OCT)—the ANTERION (Heidelberg Engineering, Heidelberg, Germany) and CASIAII (Tomey, Nagoya, Japan). Thirty-eight subjects, 18 patients with primary angle closure and 20 healthy participants with open angles, were included. The mean age was 54.7 ± 15.8 years (range: 26–75 years). One eye of each subject was randomly selected for anterior segment imaging by ANTERION and CASIAII, using the same scan pattern (6 evenly spaced radial scans across the anterior segment for three times) in the same visit. The between- and within-instrument agreement and repeatability coefficients of angle open distance (AOD500), trabecular-iris space area (TISA500), lens vault (LV), scleral spur-scleral spur distance (SSD), anterior chamber depth (ACD), and pupil diameter (PD) were measured. The anterior and posterior boundaries of the cornea, iris, and lens were automatically segmented by the SS-OCT instruments; the scleral spur was manually located by a single masked observer. There were significant differences between ANTERION and CASIAII measurements; the SSD, PD, and ACD were smaller whereas AOD500 and TISA500 were greater in ANTERION compared with CASIAII (P < 0.001). Anterior segment measurements obtained from the two SS-OCT instruments showed strong associations (R2 ranged between 0.866 and 0.998) although the between-instrument agreement was poor; the spans of 95% limits of between-instrument agreement were ≥ 1.5-folds than the within-instrument agreement for either instrument. Whereas both SS-OCT instruments showed low test–retest measurement variabilities, the repeatability coefficients of AOD500, TISA500, ACD, and PD were slightly smaller for CASIAII than ANTERION (P ≤ 0.012).

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Understanding diagnostic disagreement in angle closure assessment between anterior segment optical coherence tomography and gonioscopy

British Journal of Ophthalmology ◽

10.1136/bjophthalmol-2019-314672 ◽

2019 ◽

Vol 104 (6) ◽

pp. 795-799 ◽

Cited By ~ 4

Author(s):

Natalia Porporato ◽

Mani Baskaran ◽

Tin A Tun ◽

Rehena Sultana ◽

Marcus Tan ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Cross Sectional Study ◽

False Positives ◽

Angle Closure ◽

Optical Coherence ◽

Cross Sectional ◽

Swept Source

Background/aimsAlthough being a more objective tool for assessment and follow-up of angle closure, reliability studies have reported a moderate diagnostic performance for anterior segment optical coherence tomography (OCT) technologies when comparing with gonioscopy as the reference standard. We aim to determine factors associated with diagnostic disagreement in angle closure when assessed by anterior segment swept source OCT (SS-OCT, CASIA SS-1000; Tomey, Nagoya, Japan) and gonioscopy.MethodsCross-sectional study. A total of 2027 phakic subjects aged ≥50 years, with no relevant previous ophthalmic history, were consecutively recruited from a community polyclinic in Singapore. Gonioscopy and SS-OCT (128 radial scans) for the entire circumference of the angle were performed for each subject. A two-quadrant closed gonioscopic definition was used. On SS-OCT images, angle closure was defined as iridotrabecular contact (ITC) to the extent of ≥35%, ≥50% and ≥75% of the circumferential angle. Diagnostic disagreements between both methods, that is, false positives or overcalls and false negatives or undercalls were defined, respectively, as gonioscopic open/closed angles inversely assessed as closed/open by SS-OCT.ResultsTwo hundred and seventy-two (14.7%) resulted in overcall results (false positives) when ≥50% of the angle circumference was closed using SS-OCT. These eyes had significantly wider (anterior chamber width, 11.7 vs 11.6 mm, p<0.001) and deeper (anterior chamber depth (ACD), 2.4 vs 2.2 mm, p<0.001) anterior chambers than eyes assessed by both methods as closed (true positives). Deeper ACD (OR 9.31) and lower lens vault (LV) (OR 0.04) were significantly associated with a false positive diagnosis in the multivariate analysis. Most of these cases had short (52.6%) or irregular (39%) ITC in SS-OCT images.ConclusionsWe found that anterior chamber dimensions, determined by ACD and LV, were factors significantly associated with diagnostic disagreement between anterior segment SS-OCT and gonioscopy in angle closure assessment.

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Evaluation of the Anterior Chamber Angle in Angle-Closure Suspect Patients by Anterior Segment Optical Coherence Tomography (AS-OCT) and Pentacam

10.21203/rs.3.rs-684174/v1 ◽

2021 ◽

Author(s):

Mohamed Salah El-Din Mahmoud ◽

Nosiba Essam ◽

Layla Mohamed Hammouda ◽

Ahmed Shawkat Mohamed

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Angle Closure ◽

P Value ◽

Optical Coherence ◽

Anterior Chamber Angle ◽

Cross Sectional ◽

Chamber Angle

Abstract Purpose: The study aims is to detect primary angle-closure glaucoma (PACG) suspects using both anterior segment optical coherence tomography (AS-OCT) and Scheimpflug imaging. Methods: A prospective cross-sectional observational study on forty PACG suspect patients with a range of ages from 20 to 70 years. Angle imaging by AS-OCT (Optovue Inc., Fairmont, CA) with study parameters in the superior, inferior, nasal, and temporal quadrants were anterior chamber angle (ACA), angle opening distance at 750 µm (AOD750), and trabecular-iris space area at 750 μm (TISA). Also, angle imaging using Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany) with study parameters were the anterior chamber angle (ACA), anterior chamber depth (ACD) and, anterior chamber volume (ACV). The angle evaluation was done before and after the mydriatic test.Results: As regarding AS-OCT, after the mydriatic test, we noticed a decrease in all parameters measured, some decreased significantly while others did not. A significant decrease was noticed in ACA (TIA750) in all quadrants (P value<0.001in nasal, 0.001in superior &temporal, 0.003 in inferior) and in TISA750 in the nasal quadrant only (P-value 0.004). AOD750 and TISA750 in the remaining quadrants also decreased but not significantly as ACA. As regarding Pentacam, all parameters decreased after the mydriatic test. ACA (P-value <0.001) and ACD (P-value 0.004) showed significant statistical decrease but ACV showed statistically non-significant decrease (P-value 0.558).Conclusions: AS-OCT and Pentacam are reliable investigations for the detection of PACG suspects which needs more close follow-up for a possible increase in IOP.

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Changes in anterior segment optical coherence tomography following pars plana vitrectomy without tamponade

International Journal of Retina and Vitreous ◽

10.1186/s40942-021-00285-w ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Alireza Khodabande ◽

Massood Mohammadi ◽

Hamid Riazi-Esfahani ◽

Shahab Karami ◽

Massood Mirghorbani ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Pars Plana Vitrectomy ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Optical Coherence ◽

Mean Values ◽

Iop Measurement ◽

Pars Plana ◽

The Mean

Abstract Background To evaluate changes in anterior segment morphology on anterior segment optical coherence tomography (AS-OCT) following pars plana vitrectomy (PPV) without tamponade. Methods Patients who underwent PPV without tamponade for epiretinal membrane were evaluated. Eligible patients underwent intraocular pressure (IOP) measurement and AS-OCT preoperatively as well as 1 month and 6 months post-operatively. Anterior chamber width (ACW), anterior chamber depth (ACD), trabecular iris angle (TIA), angle opening distance at 500 and 750 µm (AOD), and trabecular iris space area at 500 and 750 µm (TISA) at four quadrants were recorded and analyzed. Additionally, the mean values of TIA (MTIA), AOD (MAOD), and TISA (MTISA) for each eye (mean of four quadrants) were analyzed. Results 23 patients completed the study. The mean age of participants was 56.4 ± 3.6 years of age and 13/23 (56%) were female. Mean IOP of patients was 18.1 ± 1.1, 18.3 ± 1.1, and 18.1 ± 1.2 preoperatively,1 month post-operatively, and 6 months post-operatively, respectively. (p = 0.83). No difference was detected post-operatively in measurements of ACW, ACD, MTIA, MAOD500, MAOD750, MTISA500, and MTISA750. Conclusion Pars plana vitrectomy without tamponade was not associated with changes in anterior chamber morphology.

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Prospective comparison of ultrasound biomicroscopy and anterior segment optical coherence tomography for evaluation of anterior chamber dimensions in European eyes with primary angle closure

Eye ◽

10.1038/eye.2009.103 ◽

2009 ◽

Vol 24 (2) ◽

pp. 233-239 ◽

Cited By ~ 16

Author(s):

K Mansouri ◽

J Sommerhalder ◽

T Shaarawy

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber ◽

Anterior Segment ◽

Ultrasound Biomicroscopy ◽

Angle Closure ◽

Optical Coherence ◽

Primary Angle Closure ◽

Prospective Comparison

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Assessment of anterior chamber configuration changes after phacoemulsification with swept-source optical coherence tomography

10.21203/rs.2.9863/v1 ◽

2019 ◽

Author(s):

Man Hu ◽

Qian Zheng ◽

Zhangliang Li ◽

Pingjun Chang ◽

Yun-e Zhao

Keyword(s):

Optical Coherence Tomography ◽

Cataract Surgery ◽

Anterior Chamber ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Optical Coherence ◽

Swept Source ◽

Narrow Angle ◽

Age Related ◽

Shallow Anterior Chamber

Abstract Background To assess the changes of anterior chamber angle in patients with shallow anterior chamber and normal anterior chamber after phacoemulsification and intraocular lens implantation (IOL) using anterior segment swept-source optical coherence tomography (AS-SS-OCT). Methods This was a prospective case control study; 60 eyes of 60 patients who underwent cataract surgery. Based on anterior chamber depth (ACD) and gonioscopy findings, the eyes were classified into two groups, shallow anterior chamber group (30 eyes) and normal anterior chamber group (30 eyes). AS-SS-OCT was used to measure ACD and angle parameters angle opening distance (AOD), angle recess area (ARA), trabecular iris space area(TISA), and trabecular iris angle (TIA). Serial changes in each group were measured before and 3 months after phacoemulsification and IOL, and the differences between the two groups were compared. Results All angle parameters including ACD, AOD, ARA, TISA, and TIA in both groups at 3 months after cataract surgery were significantly different from the preoperative values (p<0.01). In addition, we found significant differences of all angle parameters between groups of shallow anterior chamber (SAC) and normal anterior chamber (NAC) (All P< 0.05). Besides, the TISA750 in superior quadrant and anterior chamber volume (ACV) were significantly smaller in the group of SAC than those in the group of NAC (P = 0.041 and 0.002, respectively). Conclusions The parameters of anterior chamber increased significantly in both two groups but not increase to the same extent 3 months after phacoemulsification. Iris thickening may also be one of the narrow angle factors,not just age-related lens thickening.

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Prediction of effective Lens position using anterior segment optical coherence tomography in Chinese subjects with angle closure

BMC Ophthalmology ◽

10.1186/s12886-021-02213-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Yuzhou Wu ◽

Shunhua Zhang ◽

Yong Zhong ◽

Ailing Bian ◽

Yang Zhang ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Partial Coherence ◽

Angle Closure ◽

Optical Coherence ◽

Training Set ◽

Lens Position ◽

Regression Formula ◽

Validation Set

Abstract Purpose To assess the accuracy of biometric parameters measured by anterior segment optical coherence tomography (AS-OCT) and partial coherence interferometry (PCI) in prediction of effective lens position (ELP) compared with previous formulas in PACG patients. Methods 121 PACG eyes were randomly divided into training set (85 eyes) and validation set (36 eyes) with same procedure including AS-OCT, PCI, phacoemulsification and IOL implantation surgery. Preoperative anterior chamber depth (pre-ACD), scleral spur depth (SSD), scleral spur width (SSW), lens vault (LV) and cornea thickness (CT) were measured from AS-OCT image. Axial length (AL) and corneal power (K) were measured by PCI. All the 7 parameters were analyzed by multiple linear regression in training set and a statistic regression formula was developed. In validation set, one-way ANOVA was applied to compare the new regression formula with Sanders-Retzlaff-Kraff theoretic (SRK/T), Holladay 1, Haigis, and a regression formula developed in previous study. Results The coefficient of determination (R2) of different parameter combinations are 0.19 (pre-ACD, AL), 0.25 (AL, K) and 0.49 (SSD, AL, SSW) in training set. In validation set, the correlation between predicted and measured ELP are: new formula (R2 = 0.50, P = 0.9947) Holladay 1 (R2 = 0.12, P < 0.0001), SRK/T (R2 = 0.11, P < 0.0001) and Haigis (R2 = 0.06, P < 0.0001). Conclusion Among 7 tested parameters, pre-ACD contribute little in ELP prediction. Formula consist of SSD, AL and SSW showed better accuracy than other formulas tested.

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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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