Corneal Analysis with Swept Source Optical Coherence Tomography in Patients with Coexisting Cataract and Fuchs Endothelial Corneal Dystrophy

This study focused on defining the characteristic features of keratometry and pachymetry elevation maps based on swept source optical coherence tomography (SS OCT) in Fuchs endothelial corneal dystrophy (FECD) eyes with a coexisting cataract. 70 eyes of 35 patients diagnosed with FECD and a coexisting cataract and 70 control eyes were included in this prospective, controlled, observational, cross-sectional study. Features characteristic of intermediately affected eyes included an increased corneal thinnest thickness (CTT) (p = 0.01), 3 and 6 mm asymmetry (p < 0.0001), higher order Fourier indices (p < 0.05 and p ≤ 0.0001, respectively), chord µ, and a posterior Ectasia Screening Index (pESI) (p < 0.01). The lack of agreement between the anterior and posterior elevation map and a significant area of negative values in the posterior map were detected. In advanced FECD eyes, our study additionally revealed decreased posterior keratometry steep (Ks), keratometry flat (Kf), keratometry average (AvgK), eccentricity (Ecc), an increased corneal apex thickness (CAT), and decreased 3 and 6 mm posterior spherical indices (p < 0.0001 for all of the above). Characteristic features of subclinical FECD, independent of the corneal thickness, can be detected by SS OCT and should be considered during the preoperative assessment of patients with a coexisting cataract.

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Comparison of two novel swept-source optical coherence tomography devices to a partial coherence interferometry-based biometer

Scientific Reports ◽

10.1038/s41598-021-93999-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Tommy C. Y. Chan ◽

Marco C. Y. Yu ◽

Vivian Chiu ◽

Gilda Lai ◽

Christopher K. S. Leung ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Corneal Thickness ◽

Anterior Chamber Depth ◽

Cross Sectional Study ◽

Systematic Difference ◽

Partial Coherence ◽

Optical Coherence ◽

Cross Sectional ◽

Swept Source ◽

Partial Coherence Interferometry

AbstractTo evaluate the repeatability and agreement of corneal and biometry measurements obtained with two swept-source optical coherence tomography (SSOCT) and a partial coherence interferometry-based device. This is a cross-sectional study. Forty-eight eyes of 48 patients had three consecutive measurements for ANTERION (Heidelberg Engineering, Germany), CASIAII (Tomey, Japan) and IOLMaster500 (Carl Zeiss Meditec, USA) on the same visit. Mean keratometry (Km), central corneal thickness (CCT), anterior chamber depth (ACD) and axial length (AL) were recorded. Corneal astigmatic measurements were converted into vector components—J0 and J45. Intra-device repeatability and agreements of measurements amongst the devices were evaluated using repeatability coefficients (RCs) and Bland–Altman plots, respectively. All devices demonstrated comparable repeatability for Km (p ≥ 0.138). ANTERION had the lowest RC for J0 amongst the devices (p ≤ 0.039). Systematic difference was found for the Km and J0 obtained with IOLMaster500 compared to either SSOCTs (p ≤ 0.010). The ACD and AL measured by IOLMaster500 showed a higher RC compared with either SSOCTs (p < 0.002). Systematic difference was found in CCT and ACD between the two SSOCTs (p < 0.001), and in AL between ANTERION and IOLMaster500 (p < 0.001), with a mean difference of 1.6 µm, 0.022 mm and 0.021 mm, respectively. Both SSOCTs demonstrated smaller test–retest variability for measuring ACD and AL compared with IOLMaster500. There were significant disagreement in keratometry and AL measurements between the SSOCTs and PCI-based device; their measurements should not be considered as interchangeable.

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Comparison between Widefield Optical Coherence Tomography Devices in Eyes with High Myopia

Diagnostics ◽

10.3390/diagnostics11040658 ◽

2021 ◽

Vol 11 (4) ◽

pp. 658

Author(s):

Federico Corvi ◽

Federico Zicarelli ◽

Matteo Airaldi ◽

Salvatore Parrulli ◽

Mariano Cozzi ◽

...

Keyword(s):

Optical Coherence Tomography ◽

High Myopia ◽

Cross Sectional Study ◽

Horizontal Line ◽

Optical Coherence ◽

Cross Sectional ◽

Swept Source ◽

Image Artifact ◽

Control Subjects ◽

And Control

Background: To compare four different optical coherence tomography (OCT) devices for visualization of retinal and subretinal layers in highly myopic eyes. Methods: In this prospective, observational, cross-sectional study, consecutive patients with high myopia and control subjects were imaged by four OCT devices: Spectralis OCT2, PlexElite 2.0 100 kHz, PlexElite 2.0 200 kHz and the Canon Xephilio OCT-S1. The acquisition protocol for comparison consisted of single vertical and horizontal line scans centered on the fovea. Comparison between the devices in the extent of visible retina, presence of conjugate image or mirror artifacts, visibility of the sclerochoroidal interface and retrobulbar tissue. Results: 30 eyes with high myopia and 30 control subjects were analyzed. The visualized RPE length was significantly different between the OCT devices with Xephilio OCT-S1 imaging the largest extent (p < 0.0001). The proportion of eyes with conjugate image artifact was significantly higher with the Spectralis OCT (p < 0.0001), and lower with the PlexElite 200 kHz (p < 0.0001). No difference in visibility of the sclerochoroidal interface was noted among instruments. The retrobulbar tissue was visible in a higher proportion of eyes using swept-source PlexElite 100 kHz and 200 kHz (p < 0.007) compared to the other devices. Conclusions: In highly myopic eyes, the four OCT devices demonstrated significant differences in the extent of the retina imaged, in the prevalence of conjugate image artifact, and in the visualization of the retrobulbar tissue.

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Comparison of Two Novel Swept-Source Optical Coherence Tomography Devices to A Partial Coherence Interferometry-Based Biometer

10.21203/rs.3.rs-132028/v1 ◽

2020 ◽

Author(s):

Tommy Chan ◽

Marco Yu ◽

Vivian Chiu ◽

Gilda Lai ◽

Christopher Leung ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Anterior Chamber Depth ◽

Cross Sectional Study ◽

Systematic Difference ◽

Partial Coherence ◽

Optical Coherence ◽

Cross Sectional ◽

Swept Source ◽

Partial Coherence Interferometry ◽

Significant Disagreement

Abstract Purpose To evaluate the repeatability and agreement of cornea and biometry measurements obtained with two swept-source optical coherence tomography (SSOCT) and a partial coherence interferometry-based device.METHODS This is a cross-sectional study. Forty-eight eyes of 48 patients had three consecutive measurements for ANTERION (Heidelberg Engineering, Germany), CASIAII (Tomey, Japan) and IOLMaster500 (Carl Zeiss Meditec, USA) on the same visit. Mean keratometry (Km), central cornea thickness (CCT), anterior chamber depth (ACD) and axial length (AL) were recorded. Corneal astigmatic measurements were converted into vector components – J0 and J45. Intra-device repeatability and agreements of measurements amongst the devices were evaluated using repeatability coefficients (RCs) and Bland-Altman plots, respectively. RESULTS All devices demonstrated comparable repeatability for Km (p≥0.138). ANTERION had the lowest RC for J0 amongst the devices (p≤0.039). Systematic difference was found for the Km and J0 obtained with IOLMaster500 compared to either SSOCTs (p≤0.010). The ACD and AL measured by IOLMaster500 showed a higher RC compared with either SSOCTs (p<0.002). Systematic difference was found in CCT and ACD between the two SSOCTs (p<0.001), and in AL between ANTERION and IOLMaster500 (p<0.001), with a mean difference of 1.6 µm, 0.022mm and 0.021 mm, respectively. CONCLUSIONS Both SSOCTs demonstrated smaller test-retest variability for measuring ACD and AL compared with IOLMaster500. There were significant disagreement in keratometry and AL measurements between the SSOCTs and PCI-based device; their measurements should not be considered as interchangeable but the disagreement could be refined by readjustment of intraocular lens constant in clinical practice.

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Widefield Swept-Source Optical Coherence Tomography Angiography Assessment of Choroidal Changes in Vogt-Koyanagi-Harada Disease

Frontiers in Medicine ◽

10.3389/fmed.2021.698644 ◽

2021 ◽

Vol 8 ◽

Author(s):

Yujing Qian ◽

Jingyuan Yang ◽

Anyi Liang ◽

Chan Zhao ◽

Fei Gao ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Disease Activity ◽

Optical Coherence Tomography Angiography ◽

Comprehensive Evaluation ◽

Cross Sectional Study ◽

Optical Coherence ◽

Flow Area ◽

Cross Sectional ◽

Swept Source ◽

Vascular Abnormalities

Purpose: To investigate choroidal changes in patients with Vogt-Koyanagi-Harada disease (VKH) using widefield swept-source optical coherence tomography angiography (SS-OCTA).Methods: In this cross-sectional study, 133 eyes of 69 patients with VKH (52 eyes of 28 active VKH patients and 81 eyes of 41 inactive VKH patients) and 104 eyes of 52 age and sex matched healthy volunteers were imaged using a widefield SS-OCTA instrument. On 12 mm × 12 mm OCTA scans, mean choroidal thickness (MCT), choroidal vascularity index (CVI), choriocapillaris (CC) flow area, and mean retinal thickness (MRT) were separately calculated in the fovea (diameter of 1 mm) and in concentric rings with different radii (1–3, 3–6, 6–9, and 9–12 mm).Results: Eyes with active VKH showed significant increases in MCT, CVI, and MRT, and decreased CC flow area in all central and peripheral regions (0–1, 1–3, 3–6, 6–9, and 9–12 mm) than in the healthy eyes (p ≤ 0.01) and inactive VKH eyes (p < 0.05). Inactive VKH eyes only showed marked decrease in CC flow area in all regions compared with controls (p < 0.05). Flow voids were observed in 51 of 52 (98.1%) active VKH eyes and 50 of 81 (61.7%) inactive VKH eyes on 12 mm × 12 mm OCTA. The MCT of all regions was significantly correlated with age, disease duration, and disease activity, whereas CVI was associated with age and disease activity. The CC flow void was related to visual acuity in all regions (p < 0.05).Conclusion: Widefield SS-OCTA enables a more comprehensive evaluation of chorioretinal changes in patients with VKH disease. Structural and vascular abnormalities are observed in both the central and peripheral choroid and are closely correlated with disease activity.

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Wide-field swept source optical coherence tomography evaluation of posterior segment changes in highly myopic eyes

European Journal of Ophthalmology ◽

10.1177/11206721211062362 ◽

2021 ◽

pp. 112067212110623

Author(s):

Li-Hui Meng ◽

Ming-Zhen Yuan ◽

Xin-Yu Zhao ◽

Wei-Hong Yu ◽

You-Xin Chen

Keyword(s):

Optical Coherence Tomography ◽

Cross Sectional Study ◽

Posterior Pole ◽

Wide Field ◽

Optical Coherence ◽

College Hospital ◽

Cross Sectional ◽

Swept Source ◽

Posterior Staphyloma ◽

Comprehensive Picture

Background To investigate the features in the posterior pole of highly myopic (HM) eyes using a wide-field high-resolution swept source optical coherence tomography (SS OCT). Methods This observational cross-sectional study involved 262 eyes of 139 patients, who were diagnosed as HM and had consecutively been examined by SS OCT in the Ophthalmology Department of the Peking Union Medical College Hospital between March 2019 and December 2019. The characteristics of OCT images were documented and analyzed. Results In our study, SS OCT could demonstrate the entire layer of the choroid and detect the sclera in all eyes. The mean subfoveal retinal/choroidal/scleral thickness were 204.84 ± 119.86 μm, 92.80 ± 75.78 μm and 394.734 ± 123.09 μm, respectively. 138 eyes (52.67%) had posterior precortical vitreous pocket. Myopic foveoschisis was detected in 110 eyes (41.98%), and significantly associated with the presence of posterior staphyloma. 36 eyes (13.74%) had DSM in our study, of which 8 eyes (22.22%) showed a round dome, 16 (44.44%) were horizontal oval-shaped, 9 (25%) were vertical oval-shaped and 3 (8.34%) were oblique oval-shaped. Both SFCT and SFST were inversely and significantly associated with age and refractive errors. Macular neovascularization was significantly correlated with intrascleral vessels. Different deformation of the sclera and posterior staphyloma were vividly identified on SS OCT images. Conclusions This study provided a relatively comprehensive picture of posterior pole in HM eyes. Such good visualization of ocular fundus provided by wide-field SS OCT could be useful for the therapy option, disease condition monitoring and pathogenesis investigation.

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Morphometric evaluation and measurements of primary pterygium by anterior segment optical coherence tomography and its relation with astigmatism

Therapeutic Advances in Ophthalmology ◽

10.1177/25158414211020145 ◽

2021 ◽

Vol 13 ◽

pp. 251584142110201

Author(s):

Anuradha Raj ◽

Renu Dhasmana ◽

Harsh Bahadur

Keyword(s):

Optical Coherence Tomography ◽

Corneal Thickness ◽

Anterior Segment ◽

Cross Sectional Study ◽

Optical Coherence ◽

Cross Sectional ◽

Horizontal Length ◽

The Mean ◽

The Relationship ◽

Primary Pterygium

Purpose: To evaluate the relationship between measurements and various morphometric parameters of primary pterygium on anterior segment optical coherence tomography(AS-OCT) and refractive and keratometric astigmatism. Methods: In this cross-sectional study, patients with primary pterygium were included. The AS-OCT parameters of pterygium consisting of epithelial thickness near apex(µm), apical or head thickness(µm), its thickness at limbus(µm), horizontal length of pterygium(mm), central corneal thickness (µm) and maximum pterygium thickness(mm) were evaluated. Results: Sixty three patients comprising of 63 eyes with a primary pterygium were studied. The mean keratometric and refractive astigmatism were 1.69 ± 3.15 Diopter(D) and0.5 ± 1.4D, respectively. There was a significant association between pterygium grade and stocker’s line with keratometric astigmatism ( p = 0.02, 0.00) respectively. Vertical and horizontal length on slit lamp and horizontal length on AS-OCT showed significant association with keratometric astigmatism ( p = 0.05, 0.00,0.00), respectively. Limbal thickness on AS-OCT showed significant positive correlation with refractive astigmatism ( r = 0.29, p = 0.02). Conclusion: The pterygium grade influences the keratometric astigmatism. Increased limbal thickness of pterygium on AS-OCT leads to more refractive astigmatism.

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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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Retinal and Choroidal Thickness in relation to C-Reactive Protein on Swept-Source Optical Coherence Tomography

Journal of Immunology Research ◽

10.1155/2021/6628224 ◽

2021 ◽

Vol 2021 ◽

pp. 1-6

Author(s):

Dawei Fang ◽

Qingjian Li ◽

Ke Yan ◽

Sennan Xu ◽

Jing Jiang ◽

...

Keyword(s):

Optical Coherence Tomography ◽

Choroidal Thickness ◽

Retinal Thickness ◽

Cross Sectional Study ◽

Optical Coherence ◽

C Reactive Protein ◽

Cross Sectional ◽

Swept Source ◽

Reactive Protein ◽

Significant Difference

Purpose. To evaluate the relationships between C-reactive protein (CRP) and retinal and choroidal thickness by swept-source optical coherence tomography (SS-OCT). Methods. The participants included in the prospective cross-sectional study underwent a comprehensive ophthalmic examination. Based on the CRP values, the subjects were divided into the CRP (+) group ( CRP ≥ 8.2 mg/L) and the CRP (−) group ( CRP < 8.2 mg/L). The retinal and choroidal thickness was compared between the two groups. Results. This study enrolled 43 right eyes of 43 subjects from the CRP (+) group and 86 right eyes of 86 gender- and age-match subjects from the CRP (−) group. The choroidal thickness in the CRP (+) group was thinner than that in the CRP (−) group except for the outer nasal sector of the Early Treatment Diabetic Retinopathy Study (ETDRS) grid. However, the retinal thickness only in the inner temporal sector showed a significant difference. According to Pearson’s correlation analysis, the CRP was significantly negatively correlated with the choroidal thickness in all sectors and the retinal thickness only in the inner temporal and outer nasal sectors of the ETDRS grid. Conclusion. CRP levels are associated with retinal and choroidal thickness. The data related to the retinal and choroidal thickness changes may help understand the pathogenesis of specific ocular abnormalities in patients with systemic inflammation.

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Comparison of swept-source versus spectral-domain optical coherence tomography angiography for detection of macular neovascularization

Graefe s Archive for Clinical and Experimental Ophthalmology ◽

10.1007/s00417-021-05229-6 ◽

2021 ◽

Author(s):

Anna Lentzsch ◽

Laura Schöllhorn ◽

Christel Schnorr ◽

Robert Siggel ◽

Sandra Liakopoulos

Keyword(s):

Optical Coherence Tomography ◽

Optical Coherence Tomography Angiography ◽

Spectral Domain ◽

Optical Coherence ◽

Cross Sectional ◽

Swept Source ◽

En Face ◽

Increased Sensitivity ◽

Sensitivity Specificity ◽

Subretinal Hyperreflective Material

Abstract Purpose To compare swept-source (SS) versus spectral-domain (SD) optical coherence tomography angiography (OCTA) for the detection of macular neovascularization (MNV). Methods In this prospective cohort study, 72 eyes of 54 patients with subretinal hyperreflective material (SHRM) and/or pigment epithelial detachment (PED) on OCT possibly corresponding to MNV in at least one eye were included. OCTA scans were acquired using two devices, the PLEX Elite 9000 SS-OCTA and the Spectralis SD-OCTA. Fluorescein angiography (FA) was used as reference. Two graders independently evaluated en face OCTA images using a preset slab as well as a manually modified slab, followed by a combination of en face and cross-sectional OCTA. Results Sensitivity (specificity) for the automated slabs was 51.7% (93.0%) for SS-OCTA versus 58.6% (95.3%) for SD-OCTA. Manual modification of segmentation increased sensitivity to 79.3% for SS-OCTA but not for SD-OCTA (58.6%). The combination of en face OCTA with cross-sectional OCTA reached highest sensitivity values (SS-OCTA: 82.8%, SD-OCTA: 86.2%), and lowest number of cases with discrepancies between SS-OCTA and SD-OCTA (4.2%). Fleiss kappa as measure of concordance between FA, SS-OCTA, and SD-OCTA was 0.56 for the automated slabs, 0.60 for the manual slabs, and 0.73 (good agreement) for the combination of en face OCTA with cross-sectional OCTA. Concordance to FA was moderate for the automated slabs and good for manual slabs and combination with cross-sectional OCTA of both devices. Conclusion Both devices reached comparable results regarding the detection of MNV on OCTA. Sensitivity for MNV detection and agreement between devices was best when evaluating a combination of en face and cross-sectional OCTA.

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Evaluation of the Lower Punctum Parameters and Morphology Using Spectral Domain Anterior Segment Optical Coherence Tomography

Journal of Ophthalmology ◽

10.1155/2015/591845 ◽

2015 ◽

Vol 2015 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Riham S. H. M. Allam ◽

Rania A. Ahmed

Keyword(s):

Optical Coherence Tomography ◽

Anterior Segment ◽

Normal Subjects ◽

Cross Sectional Study ◽

Spectral Domain ◽

Outer Diameter ◽

Optical Coherence ◽

Cross Sectional ◽

Air Bubble ◽

Inner Diameter

Purpose. To study features of the lower punctum in normal subjects using spectral domain anterior segment optical coherence tomography (SD AS-OCT).Methods. Observational cross-sectional study that included 147 punctae (76 subjects). Punctae were evaluated clinically for appearance, position, and size. AS-OCT was used to evaluate the punctal shape, contents, and junction with the vertical canaliculus. Inner and outer diameters as well as depth were measured.Results. 24 males and 52 females (mean age44±14.35 y) were included. Lower punctum was perceived by OCT to be an area with an outer diameter (mean412.16±163 μm), inner diameter (mean233.67±138.73 μm), and depth (mean251.7±126.58 μm). The OCT measured outer punctum diameter was significantly less than that measured clinically (P: 0.000). Seven major shapes were identified. The junction with the vertical canaliculus was detectable in 44%. Fluid was detected in 34%, one of which had an air bubble; however, 63% of punctae showed no contents and 4% had debris.Conclusions. AS-OCT can be a useful tool in understanding the anatomy of the punctum and distal lacrimal system as well as tear drainage physiology. Measuring the punctum size may play a role in plugs fitting.

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