scholarly journals Iris Morphological Features in Patients with 360° Angle-Closure Neovascular Glaucoma: An Anterior Segment Optical Coherence Tomography Study

2018 ◽  
Vol 9 (3) ◽  
pp. 449-456 ◽  
Author(s):  
Yui Kobayashi ◽  
Shunsuke Nakakura ◽  
Etsuko Terao ◽  
Yuki Fujio ◽  
Kanae Matsuya ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Trabecular Meshwork ◽  
Pupil Diameter ◽  
Anterior Segment ◽  
Neovascular Glaucoma ◽  
Morphological Features ◽  
Angle Closure ◽  
Control Group ◽  
Optical Coherence ◽  
Swept Source

Purpose: To investigate iris morphological features in 360° angle-closure neovascular glaucoma (NVG) by swept-source anterior segment optical coherence tomography (ASOCT). Patients and Methods: In this retrospective, clinic-based, comparative study, 14 patients with 360° angle-closure NVG and 14 healthy age-matched control subjects were enrolled. All patients enrolled had no prior glaucoma surgery but underwent cataract surgery with intraocular lens implantation. Horizontal scanning images of swept-source ASOCT were analyzed using software calipers in temporal and nasal angle areas. The iris thickness at 1 and 2 mm from the pupil edge, iris length, trabecular meshwork length, peripheral anterior synechia (PAS) length, PAS height ratio (PAS length/trabecular meshwork length), and pupil diameter were measured. Results: Between the groups, there were no statistically significant differences in iris length, trabecular meshwork length, and pupil diameter (p > 0.05). However, the iris thickness was significantly reduced in the NVG group compared with the control group in the temporal and nasal areas (0.306 vs. 0.563 mm/0.326 vs. 0.645 mm at 1 mm, 0.278 vs. 0.523 mm/0.282 vs. 0.546 mm at 2 mm, respectively) (mean, all p < 0.001). In the NVG group, PAS height ratios were 1.55 ± 0.45 (mean ± standard deviation) (range, 0.58–2.30) and 1.55 ± 0.78 (range, 0.68–3.68) at the temporal and nasal angles, respectively. Conclusions: In patients with 360° angle-closure NVG, the iris thickness decreased to about 50% of that in healthy subjects, and the PAS length exceeded the trabecular meshwork length by about 1.5 times.

scholarly journals Anterior chamber angle imaging with swept-source optical coherence tomography: comparison between CASIAII and ANTERION

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Poemen Pui-man Chan ◽  
Gilda Lai ◽  
Vivian Chiu ◽  
Anita Chong ◽  
Marco Yu ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Anterior Chamber ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Angle Closure ◽  
Optical Coherence ◽  
Anterior Chamber Angle ◽  
Swept Source ◽  
Scan Pattern ◽  
Chamber Angle

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).

scholarly journals Evaluation of meridional scans for angle closure assessment with anterior segment swept-source optical coherence tomography

2020 ◽  
Vol 105 (1) ◽  
pp. 131-134
Author(s):  
Natalia Porporato ◽  
Mani Baskaran ◽  
Shamira Perera ◽  
Tin A Tun ◽  
Rehena Sultana ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Diagnostic Performance ◽  
Characteristic Curve ◽  
Anterior Segment ◽  
Cumulative Effect ◽  
Angle Closure ◽  
Main Role ◽  
Optical Coherence ◽  
Swept Source ◽  
Better Than

Background/aimsAs swept-source optical coherence tomography (SS-OCT) simultaneously obtains 128 meridional scans, it is important to identify which scans are playing the main role in classifying gonioscopic angle closure to simplify the analysis. We aimed to evaluate the diagnostic performance of every meridional scan in its ability to detect gonioscopic angle closure.MethodsObservational study with 2027 phakic subjects consecutively recruited from a community polyclinic. Gonioscopy and SS-OCT were performed. Gonioscopic angle closure was defined as non-visibility of the posterior trabecular meshwork in ≥180° of the angle, while SS-OCT was defined as iridotrabecular contact anterior to the scleral spur. The area under the receiver operating characteristic curve (AUC) was calculated to assess the diagnostic performance of each single scan, the sequential anticlockwise cumulative effect of those single scans and different combinations of them.ResultsThe AUCs of each scan ranged from 0.73 to 0.82. The single scan at 80°–260° had the highest AUC (0.82, 95% CI 0.79 to 0.84) and performed significantly better than most of the temporonasal scans (from 0° to 52° and from 153° to 179°). The superoinferior scans achieved higher AUCs compared with the temporonasal ones. When assessing the cumulative effect of adding individual scans consecutively, the peak AUC (0.80) was obtained when considering the superoinferior scans closer to 80°–85°, but no further positive cumulative effect was seen when adding the rest of the temporonasal scans of the circumference.ConclusionsIn conclusion, the single SS-OCT scan at 80°–260° had the highest diagnostic performance. Our study suggests that the 360° evaluation may not translate to better clinical utility for detection of gonioscopic angle closure.

scholarly journals A pilot study of scleral thickness in central serous chorioretinopathy using anterior segment optical coherence tomography

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yun Ji Lee ◽  
Yeon Jeong Lee ◽  
Jae Yeon Lee ◽  
Suhwan Lee
Keyword(s):  
Optical Coherence Tomography ◽  
Central Serous Chorioretinopathy ◽  
Anterior Segment ◽  
Venous Drainage ◽  
Enhanced Depth Imaging ◽  
Control Group ◽  
Study Group ◽  
Optical Coherence ◽  
Swept Source ◽  
Significant Difference

AbstractThe aim of this study is to compare the scleral thickness of central serous chorioretinopathy (CSC) eyes with controls using anterior segment optical coherence tomography (AS OCT). This prospective case control study included 15 patients (15 eyes) with CSC and 15 age and gender matched healthy subjects. All subjects underwent spectral domain OCT with enhanced depth imaging and swept source AS OCT of temporal sclera. We investigated difference in scleral thickness between the two groups and relationship between choroidal and scleral thickness. Among the 15 eyes in the study group, 1 eye had acute CSC, 4 had recurrent CSC, 7 had inactive CSC, and 3 had chronic CSC. There was no significant difference in terms of age, gender, axial length and spherical equivalent between the two groups. The choroidal and scleral thickness of the study group were significantly greater than those of the control group (P < 0.001, P = 0.034). Choroidal thickness was positively correlated with scleral thickness (P = 0.031). A thick sclera along with a thick choroid were demonstrated in CSC eyes using AS OCT. Scleral characteristics might be involved in the pathogenesis of CSC by affecting outflow resistance of venous drainage in choroidal circulation.

Iris Thickness and Severity of Neovascular Glaucoma Determined Using Swept-Source Anterior-segment Optical Coherence Tomography

2018 ◽  
Vol 27 (5) ◽  
pp. 415-420 ◽  
Author(s):  
Shunsuke Nakakura ◽  
Yui Kobayashi ◽  
Kanae Matsuya ◽  
Etsuko Terao ◽  
Yoshiaki Kiuchi
Keyword(s):  
Optical Coherence Tomography ◽  
Anterior Segment ◽  
Neovascular Glaucoma ◽  
Optical Coherence ◽  
Swept Source

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

2019 ◽  
Vol 104 (6) ◽  
pp. 795-799 ◽  
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.

scholarly journals The Role of Optical Coherence Tomography in the Diagnosis of Angle Closed Diseases of the Anterior Chamber. Part 1: Visualization of the Anterior Segment of the Eye

2021 ◽  
Vol 18 (2) ◽  
pp. 208-215
Author(s):  
N. I. Kurysheva ◽  
G. A. Sharova
Keyword(s):  
Optical Coherence Tomography ◽  
Anterior Chamber ◽  
Anterior Segment ◽  
Angle Closure ◽  
Optical Coherence ◽  
Swept Source ◽  
Primary Angle Closure ◽  
Choice Of Treatment ◽  
Closed Angle

The purpose of this work is to review the literature data on the role of optical coherence tomography in the diagnosis of diseases of the closed angle of the anterior chamber. An analysis of the modern technical devices use — optical coherence tomography of the anterior segment (AS-OST) and models with a frequency-modulated source (Swept Source) is presented. The advent of new imaging technologies such as SS-OCT is advancing the understanding of the pathogenesis of primary angle closure diseases. Visualization of the structures of the anterior segment of the eye is an important part of the strategy aimed at solving the problem of identifying risk factors, diagnosing, monitoring and evaluating the effectiveness of treatment of diseases of primary angle closure. Qualitative and quantitative data analysis based on optical coherence tomography significantly increases the diagnostic accuracy, which undoubtedly plays a key role in the choice of treatment tactics for the closed angle of the anterior chamber. The interpretation of research results should take into account the strengths and weaknesses of traditional methods and newly developed technologies.Conclusion. Optical coherence tomography of the eye’s anterior segment is a standard in modern diagnostics and evaluation of the effectiveness of treatment of diseases of primary angle closure, taking into account pathogenetic mechanisms. 

scholarly journals The Use of Anterior-Segment Optical-Coherence Tomography for the Assessment of the Iridocorneal Angle and Its Alterations: Update and Current Evidence

2021 ◽  
Vol 10 (2) ◽  
pp. 231
Author(s):  
Giacinto Triolo ◽  
Piero Barboni ◽  
Giacomo Savini ◽  
Francesco De Gaetano ◽  
Gaspare Monaco ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Intraocular Pressure ◽  
Clinical Relevance ◽  
Anterior Segment ◽  
Angle Closure ◽  
Current Evidence ◽  
Optical Coherence ◽  
Iridocorneal Angle ◽  
Wide Range

The introduction of anterior-segment optical-coherence tomography (AS-OCT) has led to improved assessments of the anatomy of the iridocorneal-angle and diagnoses of several mechanisms of angle closure which often result in raised intraocular pressure (IOP). Continuous advancements in AS-OCT technology and software, along with an extensive research in the field, have resulted in a wide range of possible parameters that may be used to diagnose and follow up on patients with this spectrum of diseases. However, the clinical relevance of such variables needs to be explored thoroughly. The aim of the present review is to summarize the current evidence supporting the use of AS-OCT for the diagnosis and follow-up of several iridocorneal-angle and anterior-chamber alterations, focusing on the advantages and downsides of this technology.

scholarly journals Objective quantification of lens nuclear opacities using swept-source anterior segment optical coherence tomography

2021 ◽  
pp. bjophthalmol-2020-318334
Author(s):  
Wei Wang ◽  
Jiaqing Zhang ◽  
Xiaoxun Gu ◽  
Xiaoting Ruan ◽  
Xiaoyun Chen ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Visual Acuity ◽  
Anterior Segment ◽  
Training Dataset ◽  
Dissipated Energy ◽  
Nuclear Density ◽  
Optical Coherence ◽  
Nuclear Cataract ◽  
Swept Source ◽  
Ultrasonic Time

Background/aimsThe primary objective is to quantify the lens nuclear opacity using swept-source anterior segment optical coherence tomography (SS-ASOCT) and to evaluate its correlations with Lens Opacities Classification System III (LOCS-III) system and surgical parameters. The secondary objective is to assess the diagnostic performance for hard nuclear cataract.MethodsThis cross-sectional study included 1222 patients eligible for cataract surgery (1222 eyes). The latest SS-ASOCT (CASIA-2) was used to obtain high-resolution lens images, and the average nuclear density (AND) and maximum nuclear density (MND) were measured by a custom ImageJ software. Spearman’s correlations analysis was used to assess associations of AND/MND with LOCS-III nuclear scores, visual acuity and surgical parameters. The subjects were then split randomly (9:1) into the training dataset and validating dataset. Receiver operating characteristic curves and calibration curves were constructed for the classification on hard nuclear cataract.ResultsThe AND and MND from SS-ASOCT images were significantly correlated with nuclear colour scores (AND: r=0.716; MND: r=0.660; p<0.001) and nuclear opalescence scores (AND: r=0.712; MND: r=0.655; p<0.001). The AND by SS-ASOCT images had the highest values of Spearman’s r for preoperative corrected distance visual acuity (r=0.3131), total ultrasonic time (r=0.3481) and cumulative dissipated energy (r=0.4265). The nuclear density had good performance in classifying hard nuclear cataract, with area under the curves of 0.859 (0.831–0.886) for AND and 0.796 (0.768–0.823) for MND.ConclusionObjective and quantitative evaluation of the lens nuclear density using SS-ASOCT images enable accurate diagnosis of hard nuclear cataract.

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