scholarly journals Swept Source Optical Coherence Tomography Angiography for Contact Lens-Related Corneal Vascularization

2016 ◽  
Vol 2016 ◽  
pp. 1-3 ◽  
Author(s):  
Marcus Ang ◽  
Yijun Cai ◽  
Anna C. S. Tan
Keyword(s):  
Optical Coherence Tomography ◽  
Image Quality ◽  
Contact Lens ◽  
Optical Coherence Tomography Angiography ◽  
Quality Score ◽  
Image Quality Score ◽  
Optical Coherence ◽  
Swept Source ◽  
Corneal Vascularization ◽  
Significant Difference

Purpose. To describe a novel technique of adapting a swept-source optical coherence tomography angiography (OCTA) to image corneal vascularization.Methods. In this pilot cross-sectional study, we obtained 3 × 3 mm scans, where 100,000 A-scans are acquired per second with optical axial resolution of 8 μm and lateral resolution of 20 μm. This was performed with manual “XYZ” focus without the anterior segment lens, until the focus of the corneoscleral surface was clearly seen and the vessels of interest were in focus on the corresponding red-free image. En face scans were evaluated based on image quality score and repeatability.Results. We analyzed scans from 10 eyes (10 patients) with corneal vascularization secondary to contact lens use in 4 quadrants, with substantial repeatability of scans in all quadrants (mean image quality score 2.7 ± 0.7;κ=0.75). There was no significant difference in image quality scores comparing quadrants (superior temporal: 2.9 ± 0.6, superior nasal: 2.8 ± 0.4, inferior temporal: 2.5 ± 0.9, and inferior nasal: 2.4 ± 1.0;P=0.276) and able to differentiate deep and superficial corneal vascularization.Conclusion. This early clinical study suggests that the swept-source OCTA used may be useful for examining corneal vascularization, which may have potential for clinical applications such as detecting early limbal stem cell damage.

scholarly journals Comparison of two different optical coherence tomography angiography devices in detecting healthy versus glaucomatous eyes – an observational cross-sectional study

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
A. R. Kee ◽  
V. C. H. Yip ◽  
E. L. T. Tay ◽  
C. W. Lim ◽  
J. Cheng ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Diagnostic Accuracy ◽  
Optic Disc ◽  
Optical Coherence Tomography Angiography ◽  
Optical Coherence ◽  
Cross Sectional ◽  
Swept Source ◽  
Retest Reliability ◽  
Significant Difference ◽  
Test Retest Reliability

Abstract Background To understand the differences between two different optical coherence tomography angiography (OCTA) devices in detecting glaucomatous from healthy eyes by comparing their vascular parameters, diagnostic accuracy and test-retest reliability. Methods A cross-sectional observational study was performed on healthy and glaucoma subjects, on whom two sets of OCTA images of optic disc and macula were acquired using both AngioVue (Optovue, USA) and Swept Source (Topcon, Japan) OCTA devices during one visit. A novel in-house software was used to calculate the vessel densities. Diagnostic accuracy of the machines in differentiating healthy versus glaucomatous eyes was determined using area under the receiver operating characteristic curve (AUROC) and test-retest repeatability of the machines was also evaluated. Results A total of 80 healthy and 38 glaucomatous eyes were evaluated. Glaucomatous eyes had reduced mean vessel density compared to healthy controls in all segmented layers of the optic disc and macula using AngioVue (p ≤ 0.001). However, glaucomatous eyes had higher mean vessel density on optic disc scans using Swept Source, with lack of statistically significant difference between healthy and glaucomatous eyes. The AUROC showed better diagnostic accuracy of AngioVue (0.761–1.000) compared to Swept Source (0.113–0.644). The test-retest reliability indices were generally better using AngioVue than Swept Source. Conclusions AngioVue showed better diagnostic capability and test-retest reliability compared to Swept Source. Further studies need to be undertaken to evaluate if there is any significant difference between the various machines in diagnosing and monitoring glaucoma.

scholarly journals Quantitative assessment of choriocapillaris flow deficits in diabetic retinopathy: A swept-source optical coherence tomography angiography study

PLoS ONE ◽  
2020 ◽  
Vol 15 (12) ◽  
pp. e0243830
Author(s):  
Yining Dai ◽  
Hao Zhou ◽  
Qinqin Zhang ◽  
Zhongdi Chu ◽  
Lisa C. Olmos de Koo ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Diabetic Retinopathy ◽  
Healthy Subjects ◽  
Optical Coherence Tomography Angiography ◽  
Optical Coherence ◽  
Swept Source ◽  
Significant Difference ◽  
En Face ◽  
The Mean

Purpose To quantitatively assess choriocapillaris (CC) flow deficits in eyes with diabetic retinopathy (DR) using swept-source optical coherence tomography angiography (SS-OCTA). Methods Diabetic subjects with different stages of DR and age-matched healthy subjects were recruited and imaged with SS-OCTA. The en face CC blood flow images were generated using previously published and validated algorithms. The percentage of CC flow deficits (FD%) and the mean CC flow deficit size were calculated in a 5-mm-diameter circle centered on the fovea from the 6×6-mm scans. Results Forty-five diabetic subjects and 27 control subjects were included in the study. The CC FD% in diabetic eyes was on average 1.4-fold greater than in control eyes (12.34±4.14% vs 8.82±2.61%, P < 0.001). The mean CC FD size in diabetic eyes was on average 1.4-fold larger than in control eyes (2151.3± 650.8μm2 vs 1574.4±255.0 μm2, P < 0.001). No significant difference in CC FD% or mean CC FD size was observed between eyes with nonproliferative DR and eyes with proliferative DR (P = 1.000 and P = 1.000, respectively). Conclusions CC perfusion in DR can be objectively and quantitatively assessed with FD% and FD size. In the macular region, both CC FD% and CC FD size are increased in eyes with DR. SS-OCTA provides new insights for the investigations of CC perfusion status in diabetes in vivo.

Intra- and Interdevice Deviation of Optical Coherence Tomography Angiography

2019 ◽  
Vol 236 (04) ◽  
pp. 551-554 ◽  
Author(s):  
Stefan Trachsler ◽  
Arthur Baston ◽  
Marcel Menke
Keyword(s):  
Optical Coherence Tomography ◽  
Healthy Subjects ◽  
Optical Coherence Tomography Angiography ◽  
Foveal Avascular Zone ◽  
Optical Coherence ◽  
Swept Source ◽  
Significant Difference ◽  
Capillary Plexus ◽  
Swept Source Oct ◽  
Scan Modes

Abstract Purpose To compare 4 optical coherence tomography-angiography (OCT-A) devices for foveal avascular zone (FAZ) measurements in healthy subjects. Methods The central retinas of 24 eyes of 12 healthy subjects were scanned with 4 different OCT-A devices (Optovue RTVue-XR, Zeiss Cirrus 5000-HD-OCT, a prototype Spectralis OCT2, Heidelberg Engineering, and Topcon DRI-OCT Triton Swept-source OCT). For the Topcon, Zeiss, and Optovue devices, 3-mm and 6-mm scans were performed. The Heidelberg device only provided 4-mm scans. En-face OCT-A images of the superficial and deep capillary plexus of the macular area were generated. The FAZ areas were measured and compared. Results Twenty-four healthy eyes were included. OCT-A devices showed significant differences in FAZ measurements. The Zeiss OCT-A device measured the smallest values for foveal avascular area (mean 218.7 mm2), followed by the Optovue device (229.6 mm2), the Topcon device (239.3 mm2), and the Heidelberg device (250.4 mm2). Differences were statistically significant for following devices: Heidelberg versus Optovue (p < 0.001), Heidelberg versus Zeiss (p < 0.001), Topcon versus Zeiss (p < 0.001), and Optovue versus Zeiss (p = 0.046). For the Optovue device, FAZ measurements were significantly different between 3 mm (mean 220 mm2) and 6 mm (mean 239.3 mm2, p = 0.007) scans. All other devices showed no significant difference within scan modes. Conclusion Current OCT-A devices provide images that allow such measurements, but values showed significant differences between devices and, for the Optovue instrument, even within scan modes. The data for OCTA measurements cannot be transferred interchangeably between the devices. Therefore, a patient should always be measured with the same device.

scholarly journals Repeatability, interocular correlation and agreement of quantitative swept-source optical coherence tomography angiography macular metrics in healthy subjects

2018 ◽  
Vol 103 (3) ◽  
pp. 415-420 ◽  
Author(s):  
Danqi Fang ◽  
Fang Yao Tang ◽  
Haifan Huang ◽  
Carol Y Cheung ◽  
Haoyu Chen
Keyword(s):  
Optical Coherence Tomography ◽  
Fractal Dimension ◽  
Correlation Coefficient ◽  
Healthy Subjects ◽  
Optical Coherence Tomography Angiography ◽  
Intraclass Correlation ◽  
Vessel Density ◽  
Optical Coherence ◽  
Swept Source ◽  
Significant Difference

PurposeTo investigate the repeatability, interocular correlation and agreement of quantitative swept-source optical coherence tomography angiography (SS-OCTA) metrics in healthy subjects.MethodsThirty-three healthy normal subjects were enrolled. The macula was scanned four times by an SS-OCTA system using the 3 mm×3 mm mode. The superficial capillary map images were analysed using a MATLAB program. A series of parameters were measured: foveal avascular zone (FAZ) area, FAZ perimeter, FAZ circularity, parafoveal vessel density, fractal dimension and vessel diameter index (VDI). The repeatability of four scans was determined by intraclass correlation coefficient (ICC). Then the averaged results were analysed for intereye difference, correlation and agreement using paired t-test, Pearson’s correlation coefficient (r), ICC and Bland-Altman plot.ResultsThe repeatability assessment of the macular metrics exported high ICC values (ranged from 0.853 to 0.996). There is no statistically significant difference in the OCTA metrics between the two eyes. FAZ area (ICC=0.961, r=0.929) and FAZ perimeter (ICC=0.884, r=0.802) showed excellent binocular correlation. Fractal dimension (ICC=0.732, r=0.578) and VDI (ICC=0.707, r=0.547) showed moderate binocular correlation, while parafoveal vessel density had poor binocular correlation. Bland-Altman plots showed the range of agreement was from −0.0763 to 0.0954 mm2 for FAZ area and from −0.0491 to 0.1136 for parafoveal vessel density.ConclusionsThe macular metrics obtained using SS-OCTA showed excellent repeatability in healthy subjects. We showed high intereye correlation in FAZ area and perimeter, moderate correlation in fractal dimension and VDI, while vessel density had poor correlation in normal healthy subjects.

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

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.

scholarly journals The Spectrum of Central Choriocapillaris Abnormalities on Swept-Source Optical Coherence Tomography Angiography in the Fellow Eye of Unilateral Exudative Age-Related Macular Degeneration Patients: From Flow Deficits to Subclinical Non-Exudative Neovascularization

2021 ◽  
Vol 10 (12) ◽  
pp. 2658
Author(s):  
Alexis Khorrami Kashi ◽  
Eric Souied ◽  
Selim Fares ◽  
Enrico Borrelli ◽  
Vittorio Capuano ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Macular Degeneration ◽  
Optical Coherence Tomography Angiography ◽  
Clinical Findings ◽  
Age Related Macular Degeneration ◽  
Optical Coherence ◽  
Swept Source ◽  
Exudative Amd ◽  
Age Related ◽  
Fellow Eyes

We evaluated the spectrum of choriocapillaris (CC) abnormalities in the fellow eyes of unilateral exudative age-related macular degeneration (AMD) patients using swept-source optical coherence tomography angiography (SS-OCTA). Fellow eyes of unilateral exudative AMD patients were prospectively included between May 2018 and October 2018. Patients underwent a multimodal imaging including a SS-OCTA. Demographics and clinical findings were analyzed. The estimated prevalence of macular neovascularization (MNV) was computed. Number and size of flow deficits (FDs) and percentage of flow deficits (FD%) were computed on the compensated CC flow images with the Fiji software. We included 97 eyes of 97 patients (mean age was 80 ± 7.66 years, 39 males, 58 females). The prevalence of MNV in the studied eyes was 8.25% (8/97 eyes). In the 89 non-neovascular eyes, FD% averaged 45.84% ± 11.63%, with a corresponding total area of FDs of 4.19 ± 1.12 mm2. There was a higher prevalence of drusenoid pigment epithelial detachment in eyes with subclinical neovascularization (p = 0.021). Fellow eyes with unilateral exudative AMD encompassed a series of CC abnormalities, from FDs of the aging CC to subclinical non-exudative MNV.

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