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    1. Geometric Perfusion Deficits: A Novel OCT Angiography Biomarker for Diabetic Retinopathy Based on Oxygen Diffusion

      Geometric Perfusion Deficits: A Novel OCT Angiography Biomarker for Diabetic Retinopathy Based on Oxygen Diffusion

      Purpose To develop geometric perfusion deficits (GPD), an optical coherence tomography angiography (OCTA) biomarker based on oxygen diffusion, and to evaluate its utility in a pilot study of healthy subjects and patients with diabetic retinopathy (DR). Design Retrospective cross-sectional study. Methods Commercial spectral-domain OCTA instruments were used to acquire repeated 3×3 mm 2 and 6×6 mm 2 motion-corrected macular OCTA volumes. En face OCTA images corresponding to the superficial capillary plexus (SCP), deep capillary plexus (DCP), and full retinal projections were obtained using automatic segmentation. For each projection, the GPD percentage and the vessel density percentage, the control ...

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    2. Validity and reliability of semiautomatic ocular cycloposition measurement with Spectralis optical coherence tomography.

      Validity and reliability of semiautomatic ocular cycloposition measurement with Spectralis optical coherence tomography.

      PURPOSE Disc-fovea angle quantification in fundus photography (P-DFA) is considered the gold standard for cycloposition assessment. The FoDi software of the SD-OCT Spectralis also measures the DFA (O-DFA) based on subject fixation and offers important clinical advantages. This study aimed to analyze the validity and reliability of OCT measuring cycloposition and to determine its performance in eyes with poor foveal definition. DESIGN Validity and reliability analysis. METHODS In 60 eyes with normal foveal definition and 32 eyes with poorly defined fovea, ocular cycloposition was assessed by two observers with five fundus photographs and five FoDi analyses each. The patients were ...

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    3. Aqueous Cytokine Expression and Higher-Order OCT Biomarkers: Assessment of the Anatomic-Biologic Bridge in the Imagine Dme Study

      Aqueous Cytokine Expression and Higher-Order OCT Biomarkers: Assessment of the Anatomic-Biologic Bridge in the Imagine Dme Study

      Purpose To identify biomarkers for predicting response to anti-VEGF therapy in diabetic macular edema (DME) and evaluate any links between cytokine expression and OCT phenotype. Design IMAGINE DME is a post-hoc image analysis and cytokine expression assessment of the DAVE randomized clinical trial. Methods Subjects were categorized as anatomical Responders or Nonresponders,and within the Responder group as Rebounders and Nonrebounders based on quantitative, longitudinal optical coherence tomography (OCT) criteria. Retinal layer and fluid features were extracted using an OCT machine-learning augmented segmentation platform. Responders were further sub-classified by rapidity of response. Aqueous concentrations of 54 cytokines at multiple timepoints ...

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    4. Guidelines for imaging the choriocapillaris using OCT angiography

      Guidelines for imaging the choriocapillaris using OCT angiography

      Purpose To provide guidance on how to appropriately quantitate various choriocapillaris (CC) parameters with optical coherence tomography angiography (OCTA). Design Evidence-based perspective. Methods Review of literature and experience of authors. Results Accurate and reliable quantification of the CC using OCTA requires that the CC can be visualized and that the measurements of various CC parameters are validated. For accurate visualization, the selected CC slab must be physiologically sound, must produce images consistent with histology, and must yield qualitatively similar images when viewing repeats of the same scan or scans of different sizes. For accurate quantification, the measured inter-capillary distances (ICDs ...

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    5. Association between sleep apnoea risk score and retinal microvasculature using optical coherence tomography angiography

      Association between sleep apnoea risk score and retinal microvasculature using optical coherence tomography angiography

      Purpose To investigate the retinal vessel changes at peripapillary and parafoveal regions using optical coherence tomography angiography in patients with varying obstructive sleep apnoea syndrome (OSAS) risk, identified by the STOP-BANG questionnaire. Design Prospective, hospital-based cross-sectional study. Methods Participants were divided into 3 groups based on the OSAS risk score. Flow areas and vessel densities were calculated at peripapillary and parafoveal regions using optical coherence tomography angiography. Microvasculature changes between the 3 groups and correlation between OSAS risk score and vascular changes were calculated. Results Six hundred and six eyes of 303 patients were included in groups 1 (n=96 ...

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      Mentions: Rohit Shetty
    6. Impact of artifacts from optical coherence tomography retinal nerve fiber layer and macula scans on detection of glaucoma progression

      Impact of artifacts from optical coherence tomography retinal nerve fiber layer and macula scans on detection of glaucoma progression

      Purpose To determine the prevalence of artifacts on segmented SDOCT images and assess their impact on the interpretation of glaucomatous progression in the retinal nerve fiber layer (RNFL) profile and macular thickness map. Design Retrospective reliability analysis Methods Retrospective review of glaucoma and glaucoma suspect eyes imaged with SDOCT during a one-month period. All cases had at least 4 sets of RNFL and macular images at 6-month intervals. SDOCT raw B-scans were examined to determine true progression and whether artifacts impacted the original interpretation of progression based on auto-segmented change maps. The co-prevalence of artifacts in the RNFL and macula ...

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      Mentions: Sanjay G. Asrani
    7. Novel Parameters to Assess the Severity of Corneal Neovascularization Using Anterior Segment Optical Coherence Tomography Angiography

      Novel Parameters to Assess the Severity of Corneal Neovascularization Using Anterior Segment Optical Coherence Tomography Angiography

      Purpose Assessment of anterior segment–optical coherence tomography angiography (AS-OCTA) to determine severity of corneal neovascularization (CoNV). Design Retrospective, cross-sectional, single-center study. Methods Patients of various CoNV etiologies were selected and classified into mild, moderate and severe. Their AS-OCTA images were measured for CoNV anterior limit, CoNV posterior limit, CoNV thickness, CoNV depth%, CoNV vessel density, CoNV area and CoNV volume. Further, AS-OCTA parameters were correlated to clinical parameters, such as classification, a numerical severity scale, vascular clock hours and best corrected visual acuity (BCVA). Results Total 19 mild, 10 moderate and 6 severe CoNV eyes were included with no ...

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    8. Role of Microscope-Intraoperative Optical Coherence Tomography in paediatric keratoplasty: A comparative Study

      Role of Microscope-Intraoperative Optical Coherence Tomography in paediatric keratoplasty: A comparative Study

      Purpose To evaluate role of Microscope-Integrated Intraoperative Optical Coherence Tomography (i-OCT) in paediatric keratoplasty. Design Combined prospective and retrospective, comparative, interventional study Setting Dr Rajendra Prasad Centre for Ophthalmic Sciences, India Methods Seventy-five children aged ≤16 years planned for keratoplasty were divided into two groups and compared for intraoperative course and postoperative outcome. In Group-1 (prospective group, n=56), pre-operative anterior segment visualization was performed clinically, with ultrasound biomicroscopy (UBM) and i-OCT and keratoplasty was commenced under i-OCT microscope. In Group-2 (retrospective group, n=19), conventional microscope was employed during keratoplasty. Results In Group-1, i-OCT, UBM and clinical examination detected ...

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    9. Lightweight Learning-based Automatic Segmentation of Subretinal Blebs on Microscope-Integrated Optical Coherence Tomography Images

      Lightweight Learning-based Automatic Segmentation of Subretinal Blebs on Microscope-Integrated Optical Coherence Tomography Images

      Purpose Subretinal injections of therapeutics are commonly used to treat ocular diseases. Accurate dosing of therapeutics at target locations is crucial but difficult to achieve using subretinal injections due to leakage, and there is no method available to measure the volume of therapeutics successfully administered to the subretinal location during surgery. Here we introduce the first automatic method for quantifying the volume of subretinal blebs, using porcine eyes injected with Ringer’s lactate solution as samples. Design Experimental study. Methods Microscope-integrated optical coherence tomography was utilized to obtain 3D visualization of subretinal blebs in porcine eyes at Duke Eye Center ...

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    10. Effects of Induced Astigmatism on Spectral Domain-OCT Angiography Quantitative Metrics

      Effects of Induced Astigmatism on Spectral Domain-OCT Angiography Quantitative Metrics

      Purpose To analyze the effect of induced astigmatism on en-face spectral-domain optical coherence tomography angiography (SD-OCTA) quantitative metrics. Design Prospective Cross-Over Study Methods Normal eyes without astigmatism and with 0.75, 1.75, and 2.75 diopters (D) of with-the-rule (WTR) astigmatism were imaged utilizing a 3x3mm scan pattern SD-OCTA CIRRUS TM 5000 HD-OCT with AngioPlex (Carl Zeiss Meditec, Dublin, CA, USA). Quantitative parameters including foveal avascular zone (FAZ) metrics, parafoveal vessel length density (VD), and perfusion density (PD) were corrected for magnification secondary to axial length and analyzed. Univariate linear regressions were performed within each eye to correlate quantitative ...

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    11. Reply to Morphologic Features of Buried Optic Disc Drusen on En Face Optical Coherence Tomography and Optical Coherence Tomography Angiography

      Reply to Morphologic Features of Buried Optic Disc Drusen on En Face Optical Coherence Tomography and Optical Coherence Tomography Angiography

      We greatly appreciate the interest that Sibony and associates 1 demonstrated in our study. The authors raised an important question regarding the definition of optic disc drusen (ODD) in our study. We know that the Optic Disc Drusen Studies Consortium defined ODD as hyporeflective lesions surrounded by hyperreflective capsules using optical coherence tomography (OCT). We previously showed that this kind of visible drusen can be observed especially in the eyes of the elderly associated with degenerative changes on OCT. 2 However, in young patients, ODD can be seen as a hyperreflective mass on OCT, located nasal to the optic disc ...

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    12. Validation of a Compensation Strategy used to Detect Choriocapillaris Flow Deficits Under Drusen with Swept Source OCT Angiography

      Validation of a Compensation Strategy used to Detect Choriocapillaris Flow Deficits Under Drusen with Swept Source OCT Angiography

      Purpose A compensation strategy that was developed to measure the choriocapillaris (CC) flow deficits (FDs) under drusen was tested in eyes with large drusen from age-related macular degeneration (AMD) before and after the drusen spontaneously resolved without evidence of disease progression. Design Prospective, observational consecutive case series. Methods Patients with AMD were enrolled in a prospective SS-OCT imaging study (PLEX® Elite 9000, Carl Zeiss Meditec). Consecutive eyes with large drusen were followed, and eyes that underwent spontaneous collapse of drusen without evidence of disease progression were identified retrospectively. The drusen-resolved regions were manually outlined. CC FDs were measured using a ...

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    13. Eliminating Visual Acuity and Dilated Fundus Exams Improves Cost Efficiency of Performing OCT-Guided Intravitreal Injections

      Eliminating Visual Acuity and Dilated Fundus Exams Improves Cost Efficiency of Performing OCT-Guided Intravitreal Injections

      Purpose The clinic efficiency and cost savings achieved by eliminating formal visual acuity (VA) and dilated fundus exams (DFEs) were assessed for established patients receiving OCT-guided intravitreal injections. Design Comparative cost analysis Methods Two different treatment models were evaluated. The first model included patients undergoing routine VA assessment, DFEs, OCT imaging, and intravitreal injections. The second model eliminated the routine VA assessment and DFE, while utilizing OCT imaging through an undilated pupil followed by the intravitreal injection. The two models incorporated both bevacizumab and aflibercept. The number of patients per clinic day, the cost per visit, and the daily revenues ...

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    14. Macular and Peripapillary OCTA Metrics Predict Progression in Diabetic Retinopathy: A Sub-analysis of TIME-2b Study Data

      Macular and Peripapillary OCTA Metrics Predict Progression in Diabetic Retinopathy: A Sub-analysis of TIME-2b Study Data

      Purpose To identify optical coherence tomography angiography (OCTA) derived vessel metrics of the macula and optic nerve head (ONH) that predict diabetic retinopathy (DR) disease progression. Design Secondary analysis of clinical trial data Methods This was a sub-analysis of prospectively collected data from 73 subjects that participated in the TIME-2b Study (Aerpio Pharmaceuticals), a multi-center clinical trial for patients with moderate to severe DR treated with AKB-9778 and followed over a 12-month period. Eligible subjects were tested every 3 months with color fundus photography, spectral domain OCT and slit-lamp biomicroscopy. OCTA of the macula and ONH was obtained for a ...

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    15. Diagnostic Accuracy of Wide-Field Map from Swept-Source Optical Coherence Tomography for Primary Open-Angle Glaucoma in Myopic Eyes

      Diagnostic Accuracy of Wide-Field Map from Swept-Source Optical Coherence Tomography for Primary Open-Angle Glaucoma in Myopic Eyes

      Purpose To compare the accuracy for glaucomatous defects and diagnostic power for primary open-angle glaucoma (POAG) between swept-source optical coherence tomography (SS-OCT) and spectral-domain optical coherence tomography (SD-OCT) in myopic eyes. Design Prospective, case-control study Methods One hundred and fifty (150) myopic POAG eyes and 100 healthy myopic eyes underwent SD-OCT and SS-OCT in random order, on the same day. The locations of glaucomatous defect on SD-OCT thickness and deviation maps and SS-OCT wide-field thickness (thickness surface) and SuperPixel maps were rated, and the maps’ accuracies were compared. The area under receiver operating characteristic (AUROC) of the peripapillary retinal nerve ...

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    16. Capillary Density Measured by OCT Angiography in Glaucomatous Optic Disc Phenotypes

      Capillary Density Measured by OCT Angiography in Glaucomatous Optic Disc Phenotypes

      Purpose To compare optical coherence tomography angiography (OCTA) measured capillary density of the optic disc among four glaucomatous optic disc phenotypes. Design Cross-sectional study. Methods Circumpapillary capillary density (cpCD) of four glaucomatous optic disc phenotypes in 193 eyes of 141 glaucoma patients and cpCD in 92 eyes of 55 healthy subjects from the Diagnostic Innovations in Glaucoma Study (DIGS) were compared. Areas under the receiver operating characteristic curves (AUROC) were used to evaluate diagnostic accuracy among groups after adjusting for confounders. Results Four glaucoma phenotypes were assessed including focal ischemic (n=45), generalized cup enlargement (n=60), myopic glaucoma (n ...

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    17. Prognostic utility of optical coherence tomography for long-term visual recovery following pituitary tumor surgery

      Prognostic utility of optical coherence tomography for long-term visual recovery following pituitary tumor surgery

      Purpose To investigate the association between optical coherence tomography (OCT) parameters and long-term visual recovery following optic chiasm decompression surgery. Design Prospective cohort study. Methods Consecutive patients undergoing pituitary or parasellar tumor resection, between January 2009 to December 2018, were recruited in a single-centre, two-year prospective, longitudinal cohort study. Best-corrected visual acuity, visual fields, and OCT retinal nerve fibre layer (RNFL) thickness, macular thickness and volume were assessed pre-operatively, and at 6 weeks, 6 months, and 2 years post-operatively. Long-term visual field recovery and maintenance was defined as a mean deviation greater than -3 at 24 months, and visual acuity ...

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    18. Optical Coherence Tomography Findings in Tamoxifen Retinopathy

      Optical Coherence Tomography Findings in Tamoxifen Retinopathy

      Purpose To describe optical coherence tomography (OCT) findings in two cases of typical tamoxifen retinopathy. Design Observational cases report. Methods Two patients with tamoxifen retinopathy were imaged with fluorescein angiography and OCT 3. Results Fluorescein angiography showed foveolar hyperfluorescence. OCT revealed a foveolar cystoid space with focal disruption of the photoreceptor line. There was no evidence of macular edema or thickening. Conclusions In both cases, OCT findings are not consistent with previous descriptions of tamoxifen retinopathy, based on fundus examination and fluorescein angiography, which include a description of macular edema. This new imaging suggests that tamoxifen maculopathy may include a ...

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    19. Foveal crack sign: an optical coherence tomography sign preceding macular hole after vitrectomy for rhegmatogenous retinal detachment

      Foveal crack sign: an optical coherence tomography sign preceding macular hole after vitrectomy for rhegmatogenous retinal detachment

      Purpose To describe an optical coherence tomography (OCT) sign preceding macular hole (MH) formation after pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD). Design Retrospective observational case series. Methods Patients who underwent PPV for RRD at Osaka Rosai Hospital between January 2014 and December 2017 were analyzed. First, the medical records of the patients who had secondary MH after RRD repair were examined, and their sequential changes of the OCT images until MH formation were evaluated. Second, the OCT findings and the medical records of all patients who underwent PPV for RRD were evaluated based on the findings of ...

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    20. Morphologic Features of Buried Optic Disc Drusen on En Face Optical Coherence Tomography and Optical Coherence Tomography Angiography

      Morphologic Features of Buried Optic Disc Drusen on En Face Optical Coherence Tomography and Optical Coherence Tomography Angiography

      We read with interest the work of Kim and associates 1 and their use of optical coherence tomography angiography (OCTA) to define peripapillary vascular structures in eyes with presumed optic disc drusen (ODD) and optic disc edema (ODE) in an effort to understand pathogenesis and local architecture. We leave the question of their definition of ODD to a separate letter for which we are co-authors and focus here on the reported vascular abnormalities in various etiologies of ODE including papilledema, optic neuritis, and nonarteritic anterior ischemic optic neuropathy (NAION). They report a significant qualitative decrease in retinal peripapillary capillary (RPC ...

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    21. Who Could Know Who I Am? The Possibility of Patient Identification With Retinal Imaging

      Who Could Know Who I Am? The Possibility of Patient Identification With Retinal Imaging

      When fugitive Jean Valjean rhetorically asks, “Who am I?” in the musical version of Victor Hugo's Les Miserables , he feared what would happen if someone recognized his face and identified him by the convict number on his yellow passport. Almost 200 years later, digital imaging of unique biological characteristics has expanded the possible means of identification. Simon and Goldstein first described a unique patient-specific retinal vascular network for identification in 1935. 1 Since the concept's advent, several variations on the assessment of retinal vessels have been proposed to improve the accuracy of identification. 2 , 3 , 4 Hill developed ...

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    22. Optimizing the Repeatability of Choriocapillaris Flow Deficit Measurement from Optical Coherence Tomography Angiography

      Optimizing the Repeatability of Choriocapillaris Flow Deficit Measurement from Optical Coherence Tomography Angiography

      Purpose To evaluate impact of processing technique and slab selection on the repeatability of choriocapillaris (CC) flow deficit (FD) measurements as assessed using optical coherence tomography angiography (OCTA) Design: prospective, cross-sectional study Methods Healthy subjects were imaged with four consecutive 3x3mm OCTA using a swept source OCT (PLEX elite 9000, Carl Zeiss Meditec, Dublin, CA). OCTA images were generated using the Max projection, and three 10 μm-thick slabs starting 11, 21 and 31 μm posterior to the automatically segmented retinal pigment epithelium (RPE) band. The resultant images were binarized using Phansalkar’s method with a 43.94 μm radius and ...

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    23. OCT Optic Nerve Head Morphology in Myopia I: Implications of Anterior Scleral Canal Opening versus Bruch’s Membrane Opening Offset

      OCT Optic Nerve Head Morphology in Myopia I: Implications of Anterior Scleral Canal Opening versus Bruch’s Membrane Opening Offset

      Purpose To measure the magnitude and direction of anterior scleral canal opening (ASCO) offset relative to Bruch’s membrane opening (BMO) (ASCO/BMO offset) in order to characterize neural canal obliqueness and minimum cross-sectional area (NCMCA) in 69 highly myopic and 138 healthy, age-matched, control eyes. Design: Cross-sectional study. Methods Using Optic Coherence Tomography (OCT) scans of the optic nerve head (ONH), BMO and ASCO were manually segmented and their centroids, size and shape were calculated. ASCO/BMO offset magnitude and direction were measured after projecting the ASCO/BMO centroid vector onto the BMO plane. Neural canal axis obliqueness was ...

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    24. A Comparison Study of Polypoidal Choroidal Vasculopathy Imaged with Indocyanine Green Angiography and Swept Source OCT Angiography

      A Comparison Study of Polypoidal Choroidal Vasculopathy Imaged with Indocyanine Green Angiography and Swept Source OCT Angiography

      Purpose Indocyanine green angiography (ICGA) was compared with swept source optical coherence tomography angiography (SS-OCTA) for the detection of polypoidal choroidal vasculopathy (PCV). Design Retrospective, cross-sectional. Methods Patients with treatment-naïve PCV based on ICGA imaging underwent same day SS-OCTA imaging at Kyung Hee University Medical Center between April 2017 to November 2018. ICGA and SS-OCTA images were graded independently. SS-OCTA images were graded using both flow and structural information. Images were graded for the number of polypoidal lesions and the total lesion area, which included both the polypoidal lesions and the branching vascular networks (BVNs). Results A total of ...

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