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Abstract The recent rise of artificial intelligence represents a revolutionary way of improving current medical practices, including cardiovascular (CV) assessment scores. Retinal vascular alterations may reflect systemic processes such as the presence of CV risk factors. The value of swept-source retinal optical coherence tomography–angiography (SS OCT-A) imaging is significantly enhanced by image analysis tools that provide rapid and accurate quantification of vascular features. We report on the interest of using machine-learning (ML) and deep-learning (DL) models for CV assessment from SS OCT-A microvasculature imaging. We assessed the accuracy of ML and DL algorithms in predicting the CHA2DS2-VASc neurocardiovascular score based on SS OCT-A retinal images of patients from the open-source RASTA dataset. The ML and DL models were trained on data from 491 patients. The ML models tested here achieved good performance with area under the curve (AUC) values ranging from 0.71 to 0.96. According to a classification into two neurocardiovascular risk groups, the EfficientNetV2-B3, a well suited DL model for retinal OCT-A images, predicted risk correctly in 68% of cases, with a mean absolute error (MAE) of approximately 0.697. Our models enable a confident prediction of the CHA2DS2-VASc score from SS OCT-A imaging, which could be a useful tool contributing to the assessment of neurocardiovascular profiles in the future.

The recent rise of artificial intelligence represents a revolutionary way of improving current medical practices, including cardiovascular (CV) assessment scores. Retinal vascular alterations may reflect systemic processes such as the presence of CV risk factors. The value of swept-source retinal optical coherence tomography–angiography (SS OCT-A) imaging is significantly enhanced by image analysis tools that provide rapid and accurate quantification of vascular features. We report on the interest of using machine-learning (ML) and deep-learning (DL) models for CV assessment from SS OCT-A microvasculature imaging. We assessed the accuracy of ML and DL algorithms in predicting the CHA2DS2-VASc neurocardiovascular score based on SS OCT-A retinal images of patients from the open-source RASTA dataset. The ML and DL models were trained on data from 491 patients. The ML models tested here achieved good performance with area under the curve (AUC) values ranging from 0.71 to 0.96. According to a classification into two neurocardiovascular risk groups, the EfficientNetV2-B3, a well suited DL model for retinal OCT-A images, predicted risk correctly in 68% of cases, with a mean absolute error (MAE) of approximately 0.697. Our models enable a confident prediction of the CHA2DS2-VASc score from SS OCT-A imaging, which could be a useful tool contributing to the assessment of neurocardiovascular profiles in the future. [ABSTRACT FROM AUTHOR]

Background/Objectives: To investigate the potential association between the endothelial dysfunction and arterial stiffness with retinal changes observed through optical coherence tomography (OCT) and OCT-angiography (OCT-A) in patients with retinal vein occlusion (RVO). Methods: Participants in this cross-sectional study were 28 patients with RVO. The demographic and clinical characteristics of all participants were recorded. Comprehensive ophthalmologic examinations were performed, including fundus photography, OCT and OCT-A. Endothelial dysfunction was assessed by measuring the endothelial glycocalyx thickness via the perfused boundary region (PBR5-25). Arterial stiffness was evaluated by measuring the carotid-femoral pulse wave velocity (PWV), the central systolic and diastolic blood pressures (cSBP and cDBP) and the augmentation index (Aix). For each ophthalmological outcome, we generated a saturated linear regression model with demographic and systemic vascular parameters serving as independent variables. Regression coefficients with the corresponding 95% confidence intervals (CIs) were reported. A p value < 0.05 was considered as statistically significant. Results: A 1 m/s increase in PWV was associated with a 0.6% reduction in inferior macular vessel density (VD) (p = 0.050). A 10 mmHg increase in cSBP was associated with a 0.03 mm2 increase in foveal avascular zone (FAZ) area (p = 0.033). A 1% increase in Aix was associated with a 0.005 mm2 increase in FAZ area (p = 0.008). A 1 μm increase in PBR5-25 was associated, on average, with a 4.4% decrease in superior peripapillary VD (p = 0.027). Conclusions: In patients with RVO, structural and microvascular retinal parameters were significantly associated with markers of endothelial dysfunction and arterial stiffness. [ABSTRACT FROM AUTHOR]

While cryotherapy is one of the traditional ways to reduce postoperative complications in maxillofacial surgery, the cooling degree is not regulated in most cases and the achieved effect is not properly controlled. Therefore, to develop optimal cooling modes, we propose to study the buccal vascular response to cooling, which has not been previously shown. To evaluate the effect of cooling, we analyzed vessel networks using optical coherence tomography angiography (OCT‐A). The cheek vessels were OCT‐A monitored using cooling by an ice bag/cooling mask. We found the advantages of using a cooling mask over an ice bag consist of a statistically significant decrease in the perfused vessel density (PVD) of the papillary layer at the oral mucosa. The absence of the reticular layer vessel reaction to any type of cooling was noted. We argue for the necessity to develop optimal modes of cryotherapy, which will contribute to blood perfusion reduction and reduction of PVD recovery. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the repeatability of retinal and choroidal optical coherence tomography angiography (OCT‐A) indices among healthy children and compare it to healthy young adults. Methods: This prospective study captured 3 mm × 3 mm and 6 mm × 6 mm macular OCT‐A scans including superficial and deep retinal layers, choriocapillaris and deep choroid over two visits, 1 week apart at approximately the same time of day, for 22 healthy adults (18–30 years) and 21 children (6–15 years). Magnification and projection‐artefact corrected indices extracted using a custom image analysis program and individual biometry were compared between visits using Bland–Altman analysis and intraclass correlation (ICC). Retinal indices included foveal avascular zone metrics, perfusion and vessel density and choroidal indices included choriocapillaris flow deficit metrics and deep choroid perfusion density, in the foveal, parafoveal and perifoveal regions. Repeatability between adults and children was compared with F‐test. Results: Bland–Altman analysis showed that the mean differences between repeated OCT‐A indices were not significantly different from zero for either of the zones, layers and scan sizes in the two age groups (p > 0.05) except for foveal vessel density and foveal avascular zone perimeter (p = 0.04 for both) of 6‐mm‐deep retinal layer scans. The ICC ranged between 0.67 and 0.99. Significantly higher variability between visits (p < 0.05) in the indices was noted among adults than children, especially for choroidal indices of larger scan size. Conclusion: The retinal and choroidal OCT‐A indices in the foveal, parafoveal and perifoveal zones were repeatable in healthy children except for the foveal vessel density and foveal avascular zone perimeter of the 6‐mm‐deep retinal layer, which exhibited statistically borderline differences between visits. The adult group showed more variability between visits compared to children, especially in the larger scan size for choroidal OCT‐A indices. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the potential association between endothelial glycocalyx damage, as well as arterial stiffness, and the retinal changes on optical coherence tomography (OCT) and OCT-angiography (OCT-A) in patients with type 2 diabetes mellitus (DM). Methods: Participants in this cross-sectional study were 65 patients with DM type 2 and 42 age- and gender-matched controls without DM. The demographic and clinical characteristics of the participants were recorded. All patients underwent a thorough ophthalmological examination and multimodal imaging, including fundus photography, OCT, and OCT-A. In addition, evaluation of the endothelial glycocalyx thickness by measuring the perfused boundary region (PBR5-25) of the sublingual microvessel, as well as of the arterial stiffness, by measuring the carotid–femoral pulse wave velocity (PWV), the central aortic pressures and the augmentation index (Aix) was performed. Univariate and multivariate logistic regression analysis was performed for the examination of the potential association between the eye imaging variables and the cardiovascular-related variables. The odds ratios (OR) with the respective 95% confidence intervals (CI) were calculated. A p-value < 0.05 was considered statistically significant. Results: Patients with DM presented significantly higher PBR5-25 compared to controls without DM (p = 0.023). At the univariate analysis, increased PBR5-25 (≥2.19 μm vs. <2.19 μm) was associated with decreased peripapillary VD at the superior quadrant (univariate OR (95% CI) = 0.34 (0.12–0.93), p = 0.037). Multivariate logistic regression analysis showed that increased PWV (≥13.7 m/s vs. <13.7 m/s) was associated with an increased foveal avascular zone (FAZ) area on OCT-A (p = 0.044) and increased FAZ perimeter (p = 0.048). Moreover, increased Aix (≥14.745% vs. <14.745%) was associated with diabetic macular edema (DME) presence (p = 0.050) and increased perifoveal and parafoveal superior and temporal thickness on OCT (p < 0.05 for all associations). Conclusions: Markers of endothelial damage and arterial stiffness were associated with structural and microvascular retinal alterations in patients with DM, pointing out that OCT-A could be a useful biomarker for detecting potential cardiovascular risk in such patients. [ABSTRACT FROM AUTHOR]

Abstract Aim of the present study is to evaluate the relationship between genetic and phenotypic data in a series of patients affected by grade I and II of foveal hypoplasia with stable fixation and good visual acuity using multimodal imaging techniques. All patients underwent complete clinical and instrumental assessment including structural Optical Coherence Tomography (OCT), OCT Angiography and Adaptive Optics (AO) imaging. Central macular thickness (CMT), inner nuclear layer (INL), vessel density in superficial capillary plexus were the main variables evaluated with OCT technology. Cone density, cone spacing, cone regularity, cone dispersion and angular density were the parameters evaluated with AO. Genetic evaluation and trio exome sequencing were performed in all affected individuals. Eight patients (3 males and 5 females) with a mean age of 12.62 years (range 8–18) were enrolled. The mean best corrected visual acuity (BCVA) was 0.18 ± 0.13 logMAR, mean CMT was 291.9 ± 16.6 µm and INL was 26.2 ± 4.6 µm. The absence of a foveal avascular zone (FAZ) was documented by examination of OCT-A in seven patients in the superficial capillary plexus. However, there was a partial FAZ in the deep plexus in patients P5 and P8. Of note, all the patients presented with major retinal vessels clearly crossing the foveal center. All individuals exhibited a grade I or II of foveal hypoplasia. In 5 patients molecular analyses showed an extremely mild form of albinism caused by compound heterozygosity of a TYR pathogenic variant and the hypomorphic p.[Ser192Tyr;Arg402Gln] haplotype. One patient had Waardenburg syndrome type 2A caused by a de novo variant in MITF. Two patients had inconclusive molecular analyses. All the patients displayed abnormalities on OCT-A. Photoreceptor count did not differ from normal subjects according to the current literature, but qualitative analysis of AO imaging showed distinctive features likely related to an abnormal pigment distribution in this subset of individuals. In patients with foveal hypoplasia, genetic and multimodal imaging data, including AO findings, can help understand the physiopathology of the foveal hypoplasia phenotype. This study confirms that cone density and visual function can both be preserved despite the absence of a pit.

Alzheimer's disease is a type of neurodegenerative disorder that is characterized by the progressive degeneration of brain cells, leading to cognitive decline and memory loss. It is the most common cause of dementia and affects millions of people worldwide. While there is currently no cure for Alzheimer's disease, early detection and treatment can help to slow the progression of symptoms and improve quality of life. This research presents a diagnostic tool for classifying mild cognitive impairment and Alzheimer's diseases using feature-based machine learning applied to optical coherence tomographic angiography images (OCT-A). Several features are extracted from the OCT-A image, including vessel density in five sectors, the area of the foveal avascular zone, retinal thickness, and novel features based on the histogram of the range-filtered OCT-A image. To ensure effectiveness for a diverse population, a large local database for our study was collected. The promising results of our study, with the best accuracy of 92.17,% will provide an efficient diagnostic tool for early detection of Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Alzheimer's disease is the most prevalent form of dementia. Apart from its traditional clinical diagnostic methods, novel ocular imaging biomarkers have the potential to significantly enhance the diagnosis of Alzheimer's disease. Ophthalmologists might be able to play a crucial role in this multidisciplinary approach, aiding in the early detection and diagnosis of Alzheimer's disease through the use of advanced retinal imaging techniques. This systematic literature review the utilization of optical coherence tomography angiography biomarkers, specifically vessel density and the foveal avascular zone, for the diagnosis of Alzheimer's disease. A comprehensive search was performed across multiple academic journal databases, including 11 relevant studies. The selected studies underwent thorough analysis to assess the potential of these optical coherence tomography angiography biomarkers as diagnostic tools for Alzheimer's disease. The assessment of vessel density and the foveal avascular zone have emerged as a promising avenue for identifying and diagnosing Alzheimer's disease. However, it is imperative to acknowledge that further targeted investigations are warranted to address the inherent limitations of the existing body of literature. These limitations encompass various factors such as modest sample sizes, heterogeneity among study populations, disparities in optical coherence tomography angiography imaging protocols, and inconsistencies in the reported findings. In order to establish the clinical utility and robustness of these biomarkers in Alzheimer's disease diagnosis, future research endeavors should strive to overcome these limitations by implementing larger-scale studies characterized by standardized protocols and comprehensive assessments. [ABSTRACT FROM AUTHOR]

We present a case involving a patient whose clinical phenotype aligns with oculocutaneous albinism (OCA), yet exhibits a complex genotype primarily characterized by variants of unknown significance (VUS). An 11-year-old boy manifested iris hypopigmentation and translucency, pronounced photophobia, diminished visual acuity and stereopsis, nystagmus, reduced pigmentation of the retina, and foveal hypoplasia. Genetic testing was performed. A heterozygous missense VUS CAPN5 c.230A>G, p.(Gln77Arg), a heterozygous missense VUS TYR c.1307G>C, p.(Gly436Ala), and a heterozygous missense variant TYR c.1205G>A, p.(Arg402Gln) which was classified as a risk factor, were identified. We hypothesized that the TYR c.1307G>C, p.(Gly436Ala) variant is in genetic disequilibrium with the TYR c.1205G>A, p.(Arg402Gln) variant leading to deficient expression of melanogenic enzymes in retinal cells, resulting in the manifestation of mild OCA. Additionally, this study represents the case where we did not detect chiasmal misrouting in visual evoked potentials, nor did we observe a shift in the distribution of ganglion cell thickness from a temporal to a central position. Moreover, our patient's case supports the probable benign nature of the CAPN5 c.230A>G, p.(Gln77Arg) variant. [ABSTRACT FROM AUTHOR]

Background/Objectives: This study aims to investigate the long-term effect of inactive systemic lupus erythematosus (SLE) on the retinal microcirculation measured via optical coherence tomography angiography (OCT-A). Methods: Twenty-four eyes of 24 patients with inactive SLE under hydroxychloroquine (HCQ) therapy were included. The OCT-A data (mainly vessel density (VD) and foveal avascular zone (FAZ) data of the superficial and of the deep capillary plexus (SCP, DCP) and the choriocapillaris (CC)) were analyzed and compared between the baseline examination (t0) and 2 years later (t1). Results: At t1, VD in the whole en face SCP and in the CC was notably reduced compared to t0 (SCP: p = 0.001, CC: p = 0.013). VD in the DCP, CRT and FAZ area showed no difference at t1 compared to t0 (DCP: p = 0.128, FAZ: p = 0.332, CRT fovea: p = 0.296). Correlation analysis between the increase in cumulative doses of HCQ between t0 and t1 and the VD of the whole en face SCP did not show any correlation (Spearman r = 0.062 (95% CI −0.367; 0.477). Conclusions: SLE patients demonstrated a decrease in the retinal VD of the SCP and CC over a 2-year period. There was no correlation with the change in cumulative doses of HCQ. These results suggest an ongoing effect of the disease on the retinal and choriocapillary microcirculation. [ABSTRACT FROM AUTHOR]

Background: Systemic microvascular regression and dysfunction are considered important underlying mechanisms in heart failure with preserved ejection fraction (HFpEF), but retinal changes are unknown. Methods: This prospective study aimed to investigate whether retinal microvascular and structural parameters assessed using optical coherence tomography angiography (OCT-A) differ between patients with HFpEF and control individuals (i.e., capillary vessel density, thickness of retina layers). We also aimed to assess the associations of retinal parameters with clinical and echocardiographic parameters in HFpEF. HFpEF patients, but not controls, underwent echocardiography. Macula-centered 6 × 6 mm volume scans were computed of both eyes. Results: Twenty-two HFpEF patients and 24 controls without known HFpEF were evaluated, with an age of 74 [68–80] vs. 68 [58–77] years (p = 0.027), and 73% vs. 42% females (p = 0.034), respectively. HFpEF patients showed vascular degeneration compared to controls, depicted by lower macular vessel density (p < 0.001) and macular ganglion cell-inner plexiform layer thickness (p = 0.025), and a trend towards lower total retinal volume (p = 0.050) on OCT-A. In HFpEF, a lower total retinal volume was associated with markers of diastolic dysfunction (septal e', septal and average E/e': R2 = 0.38, 0.36, 0.25, respectively; all p < 0.05), even after adjustment for age, sex, diabetes mellitus, or atrial fibrillation. Conclusions: Patients with HFpEF showed clear levels of retinal vascular changes compared to control individuals, and retinal alterations appeared to be associated with markers of more severe diastolic dysfunction in HFpEF. OCT-A may therefore be a promising technique for monitoring systemic microvascular regression and cardiac diastolic dysfunction. [ABSTRACT FROM AUTHOR]

Introduction: There is a high and ever-increasing global prevalence of diabetic retinopathy (DR) and invasive imaging techniques are often required to confirm the presence of proliferative disease. The aim of this study was to explore the images of a rapid and non-invasive technique, widefield optical coherence tomography angiography (OCT-A), to study differences between patients with severe non-proliferative and proliferative DR (PDR). Methods: We conducted an observational longitudinal study from November 2022 to March 2023. We recruited 75 patients who were classified into a proliferative group (28 patients) and severe non-proliferative group (47 patients). Classification was done by specialist clinicians who had full access to any multimodal imaging they required to be confident of their diagnosis, including fluorescein angiography. For all patients, we performed single-shot 4 × 4 and 10 × 10 mm (widefield) OCT-A imaging and when possible, the multiple images required for mosaic 17.5 × 17.5 mm (ultra widefield) OCT-A imaging. We assessed the frequency with which proliferative disease was identifiable solely from these OCT-A images and used custom-built MATLAB software to analyze the images and determine computerized metrics such as density and intensity of vessels, foveal avascular zone, and ischemic areas. Results: On clinically assessing the OCT-A 10 × 10 fields, we were only able to detect new vessels in 25% of known proliferative images. Using ultra-widefield mosaic images, however, we were able to detect new vessels in 100% of PDR patients. The image analysis metrics of 4 × 4 and 10 × 10 mm images did not show any significant differences between the two clinical groups. For mosaics, however, there were significant differences in the capillary density in patients with PDR compared to severe non-PDR (9.1% ± 1.9 in the PDR group versus 11.0% ± 1.9 for severe group). We also found with mosaics a significant difference in the metrics of ischemic areas; average area of ischemic zones (253,930.1 ± 108,636 for the proliferative group versus 149,104.2 ± 55,101.8 for the severe group. Conclusions: Our study showed a high sensitivity for detecting PDR using only ultra-widefield mosaic OCT-A imaging, compared to multimodal including fluorescein angiography imaging. It also suggests that image analysis of aspects such as ischemia levels may be useful in identifying higher risk groups as a warning sign for future conversion to neovascularization. [ABSTRACT FROM AUTHOR]

PurposeFemale carriers of X-linked inherited retinal diseases (IRDs) can show highly variable phenotypes and disease progression. Vascular reactivity, a potential disease biomarker, has not been investigated in female IRD carriers. In this study, functional optical coherence tomography angiography (OCT-A) was used to dynamically assess the retinal microvasculature of X-linked IRD carriers.MethodsGenetically confirmed female carriers of IRDs (choroideremia or X-linked retinitis pigmentosa), and healthy women were recruited. Macular angiograms (3x3mm, Zeiss Plex Elite 9000) were obtained in 36 eyes of 15 X-linked IRD female carriers and 21 age-matched control women. Two tests were applied to test vascular reactivity: (i) mild hypoxia and (ii) handgrip test, to induce a vasodilatory or vasoconstrictive response, respectively. Changes to vessel density (VD) and vessel length density (VLD) were independently evaluated during each of the tests for both the superficial and deep capillary plexuses.ResultsIn the control group, the superficial and deep VD decreased during the handgrip test (p0.05).ConclusionsFunctional OCT-A is a useful tool to assess dynamic retinal microvascular changes. Subclinical impairment of the physiological vascular responses seen in carriers of X-linked IRDs may serve as a valuable clinical biomarker.

Background/Objectives: To investigate the potential association between the endothelial dysfunction and arterial stiffness with retinal changes observed through optical coherence tomography (OCT) and OCT-angiography (OCT-A) in patients with retinal vein occlusion (RVO). Methods: Participants in this cross-sectional study were 28 patients with RVO. The demographic and clinical characteristics of all participants were recorded. Comprehensive ophthalmologic examinations were performed, including fundus photography, OCT and OCT-A. Endothelial dysfunction was assessed by measuring the endothelial glycocalyx thickness via the perfused boundary region (PBR5-25). Arterial stiffness was evaluated by measuring the carotid-femoral pulse wave velocity (PWV), the central systolic and diastolic blood pressures (cSBP and cDBP) and the augmentation index (Aix). For each ophthalmological outcome, we generated a saturated linear regression model with demographic and systemic vascular parameters serving as independent variables. Regression coefficients with the corresponding 95% confidence intervals (CIs) were reported. A p value < 0.05 was considered as statistically significant. Results: A 1 m/s increase in PWV was associated with a 0.6% reduction in inferior macular vessel density (VD) (p = 0.050). A 10 mmHg increase in cSBP was associated with a 0.03 mm2 increase in foveal avascular zone (FAZ) area (p = 0.033). A 1% increase in Aix was associated with a 0.005 mm2 increase in FAZ area (p = 0.008). A 1 μm increase in PBR5-25 was associated, on average, with a 4.4% decrease in superior peripapillary VD (p = 0.027). Conclusions: In patients with RVO, structural and microvascular retinal parameters were significantly associated with markers of endothelial dysfunction and arterial stiffness.

Purpose: To evaluate the optical coherence tomography angiogram changes in non-active severe thyroid-related ophthalmopathy patients after cosmetic bone decompression. Methods: Eighteen patients (25 eyes) with severe not active not compressive (NANC) TED who were candidates for decompression surgery for cosmetic reasons were included in this study, and a 3 × 3 mm macular scan was used to measure vessel density and RNFL thickness. Whole macular vessel density in its superficial, deep and choriocapillaris layers was evaluated. The following data were extracted for each of layers: superior and inferior hemispheres, fovea, parafoveal vessel density, its superior and inferior hemispheres, and temporal, superior, nasal and inferior quadrant. Results: The mean RPC increased postoperatively, which was statistically significant in small vessels of peripapillary area (p-value = 0.045). The mean RNFL thickness decreased after surgery and it was statistically significant in the peripapillary (p-value = 0.032) and Inferior-Hemifield area (p-value = 0.036). The choriocapillaris changes were significant in Superior-Hemifield (p-value = 0.031) and Fovea (p-value = 0.03). Conclusion: Thyroid-associated orbitopathy patients have a tendency to decrease vascular density and correlated with disease activity more than stage of orbitopathy. There was not a strong and even discrepant result in linkage of RNFL thickness and other optic nerve function tests and TED patient status and it is needed to do studies with more epidemiologic power and same methodology of study to be more comparable. [ABSTRACT FROM AUTHOR]

PrecisMacular superficial capillary plexus (SCP) vessel density is more informative than deep capillary plexus (DCP) vessel density for the detection of glaucoma.PurposeThe purpose of this study was to characterize optical coherence tomography angiography macular SCP and projection-resolved DCP vessel densities and compare their diagnostic accuracies with ganglion cell complex (GCC) thickness in healthy, glaucoma suspect, and glaucoma eyes.Materials and methodsSixty-eight eyes of 44 healthy subjects, 26 eyes of 16 preperimetric glaucoma suspects, and 161 eyes of 124 glaucoma patients from the Diagnostics Innovations in Glaucoma Study with good quality high-density 6×6 mm2 macula optical coherence tomography angiography images were included. The diagnostic accuracy of SCP vessel density, projection-resolved DCP vessel density and GCC thickness were compared among groups.ResultsMean whole image vessel density (wiVD; % of area occupied by vessels containing flowing blood) in the SCP layer was highest in healthy eyes (49.7%), followed by glaucoma suspect eyes (46.0%), and glaucoma eyes (40.9%) (P

There has been considerable progress in implicit neural representation to upscale an image to any arbitrary resolution. However, existing methods are based on defining a function to predict the Red, Green and Blue (RGB) value from just four specific loci. Relying on just four loci is insufficient as it leads to losing fine details from the neighboring region(s). We show that by taking into account the semi-local region leads to an improvement in performance. In this paper, we propose applying a new technique called Overlapping Windows on Semi-Local Region (OW-SLR) to an image to obtain any arbitrary resolution by taking the coordinates of the semi-local region around a point in the latent space. This extracted detail is used to predict the RGB value of a point. We illustrate the technique by applying the algorithm to the Optical Coherence Tomography-Angiography (OCT-A) images and show that it can upscale them to random resolution. This technique outperforms the existing state-of-the-art methods when applied to the OCT500 dataset. OW-SLR provides better results for classifying healthy and diseased retinal images such as diabetic retinopathy and normals from the given set of OCT-A images. [ABSTRACT FROM AUTHOR]

The prevalence of multiple sclerosis (MS) has been increasing among young people in developing countries over the last years. With the continuous development of new technology, the diagnosis and follow-up of these patients has received new parameters that physicians may use in their practice. This paper reviews the main biomarkers identified through Optical Coherence Tomography Angiography (OCT-A) involved in the development and progression of MS and investigates the role it may have in detecting changes to the central nervous system (CNS). [ABSTRACT FROM AUTHOR]

To compare the microvasculature of the optic disc in open-angle glaucoma (OAG) and angle-closure glaucoma (ACG) after trabeculectomy. This study included 34 patients divided into two groups based on the angle: (1) the OAG Group, which included 24 eyes from 24 patients, and (2) the ACG Group, which included ten eyes from 10 patients. All patients were subjected to comprehensive ophthalmic examinations. It included best-corrected visual acuity (BCVA), Goldmann applanation tonometry, gonioscopy, slit-lamp biomicroscopy, dilated fundus examination, and stereoscopic examination of the optic disc. The central corneal thickness was measured using a Nidek AL scan optical biometer. The visual field was evaluated by standard automated perimetry using Humphrey Field Analyzer (24–2 Swedish interactive threshold algorithm; Carl-Zeiss Meditec, Dublin, CA). Moreover, optical coherence tomography angiography (OCT-A) was performed utilizing the RTVue XR Avanti scanner (Optovue Inc., Fremont, CA, USA) preoperatively as well as 1 month after surgery. There was a statistically significant increase in optic disc vessel density (VD) in the whole image, radial peripapillary, inferior, superior, temporal, and nasal quadrant in OAG after surgery. Regarding the change in VD after surgery in ACG patients, there was a statistically significant increase in optic disc VD in the whole image, radial peripapillary, inferior, superior, temporal, and nasal quadrant in ACG after surgery. Regarding the percentage of VD change following trabeculectomy surgery, there were highly significant differences between the two groups for the whole image, radial peripapillary, inferior quadrant, and temporal quadrant VD. Statistically significant changes were also observed in the superior and nasal quadrants of VD. However, no significant change in VD was detected within the disc. In conclusion, the optic disc VD improved after the reduction of intraocular pressure (IOP) by surgery in both OAG and ACG. However, ACG demonstrated a significant improvement than the OAG. [ABSTRACT FROM AUTHOR]

Background and Objectives: Early diagnosis of the exudative form of age-related macular degeneration (AMD) is very important for a timely first treatment, which is directly related to the preservation of functional visual acuity over a long period. The goal of this paper was to examine the correlation between the double-layer sign (DLS) and the presence of non-exudative macular neovascularization (MNV). Materials and Methods: Our research included 60 patients with AMD, exudative in one eye and non-exudative in the other eye. We analyzed only the non-exudative form using optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A). The patients were classified into three groups, depending on the duration of the disease (<2 years, 2 to 5 years, >5 years). The onset of the disease was deemed the moment of establishing a diagnosis of exudative AMD in one eye. We defined the presence or absence of a DLS using OCT and the presence of non-exudative MNV using OCT-A, both on 3 × 3 mm and 6 × 6 mm sections. DLS was used as a projection biomarker for non-exudative MNV, with the aim of establishing a rapid diagnosis and achieving early treatment of the disease. Results: We found that there was a statistically significant correlation between the DLS diagnosed using OCT and non-exudative MNV diagnosed by OCT-A for both 3 × 3 mm (p < 0.001) and 6 × 6 mm (p < 0.001) imaging. There was a statistically significant difference between the frequencies of both DLS and MNV in Groups I and III on both 3 × 3 and 6 × 6 mm imaging. A statistically significant difference was also noted in the frequencies of DLS and MNV on 6 × 6 mm imaging, but not on 3 × 3 mm imaging, between Groups I and II. No differences were found between the frequencies of DLS and MNV between Groups II and III. Conclusions: The DLS on OCT can be used as a projection biomarker to assess the presence of a non-exudative MNV. [ABSTRACT FROM AUTHOR]

At present about 16.4 million people in the world suffer from retinal venous occlusions (RVO). The pathophysiology of RVO includes changes in the vascular wall, blood flow, blood clotting. The key role in the pathogenesis of this group of diseases is played by ischemia and retinal hypoxia, leading to neovascularization. Macular edema (ME) is the most common complication of retinal vein occlusions. Optical coherence tomography-angiography (OCTA) is considered as an informative and highly sensitive method for diagnosing macular edema (ME) and ischemic zones in RVO. Intravitreal administration of glucocorticosteroids and/or angiogenesis inhibitors is the priority treatment method for macular edema in RVO. The combination of antiangiogenic therapy and laser treatment is promising. The navigation treatment technology is implemented under the conditions of the Navilas 577 system. The Navilas 577 laser navigation system is a laser coagulator with a tracking system and a fundus camera. The possibility of planning the operation, superimposing the results of OCTA on a fundus image makes the treatment faster, more accurate, and minimizes damage to healthy tissues.Purpose: to evaluate the results of target topographically oriented threshold laser coagulation in the treatment of post-thrombotic ME using theNavilas 577 laser navigation system following intravitreal administration of angiogenesis inhibitors.Materials and methods. There was performed a prospective study of the results of navigation laser treatment on the Navilas 577 device after intravitreal injections of angiogenesis inhibitors in 14 patients (14 eyes), aged 51 to 83 years, with macular edema up to 390 μm due to the branch central retinal vein occlusion. Laser treatment was performed within 2 weeks to 1 month following the last injection of angiogenesis inhibitors. The zones of ischemia in the macula were determined according to OCT-A data, imported into the Navilas 577 navigation system and superimposed on a color fundus image. Then the treatment was planned — the position of the future coagulates was marked.Results. In 3 months, there was a decrease in the height of edema from 366.5 (323;390) to 280 (270;300) μm, an increase in light sensitivity in the central retinal zone from 17 to 21.2 dB and an increase in visual acuity from 0.4 (0.3;0.5) to 0.5 (0.45;0.6).Conclusion. The combination of navigation retinal laser coagulation and angiogenesis inhibitors in the treatment of low post-thrombotic edema (less than 390 μm) gives good results; therefore, it can be justified and advisable in real clinical practice.

Abstract Background and objectives Recent literature on multiple sclerosis (MS) demonstrates the growing implementation of optical coherence tomography–angiography (OCT-A) to discover potential qualitative and quantitative changes in the retina and optic nerve. In this review, we analyze OCT-A studies in patients with MS and examine its utility as a surrogate or precursor to changes in central nervous system tissue. Methods PubMed and EMBASE were systematically searched to identify articles that applied OCT-A to evaluate the retinal microvasculature measurements in patients with MS. Quantitative data synthesis was performed on all measurements which were evaluated in at least two unique studies with the same OCT-A devices, software, and study population compared to controls. A fixed-effects or random-effects model was applied for the meta-analysis based on the heterogeneity level. Results The study selection process yielded the inclusion of 18 studies with a total of 1552 evaluated eyes in 673 MS-associated optic neuritis (MSON) eyes, 741 MS without optic neuritis (MSNON eyes), and 138 eyes without specification for the presence of optic neuritis (ON) in addition to 1107 healthy control (HC) eyes. Results indicated that MS cases had significantly decreased whole image superficial capillary plexus (SCP) vessel density when compared to healthy control subjects in the analyses conducted on Optovue and Topcon studies (both P

AbstractOptical coherence tomography angiography (OCT-A) is a noninvasive diagnostic method for three-dimensional visualization of the vascular structures of the retina and choroid. The aim of this study was to evaluate the diagnostic role of OCT-A preoperatively and postoperatively in vitreoretinal interface (VRI) pathologies, by determining the size of the foveal avascular zone (FAZ) in the superficial (SCP) and deep capillary plexus (DCP) and to compare these parameters with control (healthy) eyes. Medical records of 19 patients were prospectively analyzed: nine with a full-thickness macular hole (FTMH) and ten with an idiopathic epiretinal membrane (ERM). All participants underwent unilateral Pars Plana Vitrectomy, peeling of internal limiting membrane and fluid-gas exchange tamponade. The FAZ area of the SCP and DCP was statistically significantly different preoperatively and postoperatively at the 1st month in the FTMH group (0.5311 ± 0.276 mm2 vs. 0.4278 ± 0.257 mm2, p-value .000; 1.4822 ± 0.727 mm2 vs. 0.5856 ± 0.498 mm2 p-value .005). The mean preoperative FAZ in both plexuses was bigger compared to the control eyes. The FAZ area of the SCP and DCP was nonsignificantly different preoperatively and postoperatively in patients with ERM, despite a decrease in the mean FAZ area at the 1st month (0.3120 ± 0.1134 mm2 vs. 0.2300 ± 0.1158 mm2, p-value .150; 0.7100 ± 0.6607 vs. 0.5190 ± 0.5591 mm2, p-value .091). The results of this prospective study suggest that OCT-A is an effective and safe method in VRI pathologies, giving a valuable information for surgical outcome. Due to its high diagnostic value, the prognosis for the recovery of visual function after surgical treatment can be assessed.

Purpose: to assess the vasculature and thickness of the macula using OCT-A in patients who had experienced a previous episode of Leber hereditary optic neuropathy (LHON) or non-arteritic anterior ischemic optic neuropathy (NA-AION). Methods: twelve eyes with chronic LHON and ten eyes with chronic NA-AION and eight NA-AION fellow eyes were examined using OCT-A. The vessel density was measured in the superficial and deep plexus of the retina. Moreover, the full and inner thicknesses of the retina were assessed. Results: There were significant differences in all sectors between the groups in regard to the superficial vessel density and the inner and full thicknesses of the retina. The nasal sector of the macular superficial vessel density was affected more in LHON than in NA-AION; the same with the temporal sector of the retinal thickness. There were no significant differences between the groups in the deep vessel plexus. There were no significant differences between the vasculature of the inferior and superior hemifields of the macula in all groups and no correlation with the visual function. Conclusions: The superficial perfusion and structure of the macula assessed with OCT-A are affected both in chronic LHON and NA-AION, but more in LHON eyes, especially in the nasal and temporal sectors. [ABSTRACT FROM AUTHOR]

PURPOSE: The purpose of this study was to identify biomarkers that predict the response of treatment-naive idiopathic choroidal neovascularization (iCNV) to anti-VEGF treatment. METHODS: Fourteen eyes diagnosed with iCNV underwent a dilated fundus examination, Swept Source Optical Coherence Tomography (SS-OCT) and Optical Coherence Tomography - Angiography (OCT-A), and were given an anti-VEGF injection. The same examinations were repeated at every follow-up visit. Analysis of the pre- and posttreatment images was done to identify possible biomarkers which were evaluated to check association with decreased need for multiple anti-VEGF injections. RESULTS: At presentation, 11 patients showed a compact pattern, while three patients showed an arborizing pattern on OCT angiography (P = 1). On follow-up imaging, seven patients showed a marked response, five patients showed a moderate response, and two patients showed a mild response to anti-VEGF injection. Among the seven patients showing a marked response, only one required a repeat injection (P = 0.03). On analysis of SS-OCT, a novel Retinal Pigment Epithelium (RPE) healing response was observed in posttreatment imaging of six patients (P = 0.59). CONCLUSION: A "marked" response to the first anti-VEGF injection results in a more sustained response and is a positive prognostic factor. RPE healing response is an interesting observation that merits further evaluation. Morphology of neovascular membranes has no effect on long-term need for multiple anti-VEGF injections. Keywords: [ABSTRACT FROM AUTHOR]

Copyright of Neurologie Pro Praxi is the property of SOLEN sro and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Mohamed A Awwad,1 Mohamed Masoud,1 Mona Ahmed Elhadad2 1Department of Ophthalmology, Benha University Hospital, Benha, Qualubia, Egypt; 2Department of Anesthesia and Surgical Intensive Care, Benha University Hospital, Benha, Qualubia, EgyptCorrespondence: Mohamed A Awwad, Department of Ophthalmology, Benha University Hospital, Benha, Qualubia, Egypt, Tel +20 1017014208, Email mohamed.awad@fmed.bu.edu.eg; mohdzahir82.ma@gmail.comObjective: To assess the effect of peribulbar anesthesia on retinal microvasculature in primary open-angle glaucoma (POAG) patients undergoing cataract surgery using OCT Angiography.Participants: Forty-nine patients undergoing cataract surgery were divided into two groups. Group I included patients with no history of glaucoma, while group II included patients previously diagnosed as POAG with controlled IOP. Each participant received 6 mL of peribulbar anesthetic injection of 4 mL lidocaine 2% containing 150 IU hyaluronidase and 2 mL bupivacaine 0.5%. They were scanned with the OCT-A 10 minutes before and 10 minutes after injection for foveal deep (DCP), superficial (SCP) capillary plexuses density and total vessel density, foveal avascular zone (FAZ) diameter, optic disc total vessel density, and radial peripapillary capillary (RPC) network density. In addition, IOP was checked before and 10 minutes after injection.Results: Median percent change in DCP post-injection was significantly greater in group II (− 43%) than in group I (− 2.5%) (P < 0.001). Also, DCP total density median percent change post-injection was significantly higher in group II (− 21%) than in group I (− 0.9%) (P < 0.001). Foveal SCP vessel density and total vessel density median percent change post-injection were − 62.6% and − 16.2%, respectively, in group II and were − 2.6% and − 1.1%, respectively, in group I, which are statistically significant (P < 0.001). The FAZ diameter median percentage change post-injection was higher in group II (40.6%) than in group I (2.5%) (P < 0.001). Optic disc total vessel density and radial peripapillary capillary (RPC) network density post-injection median percent change were significantly higher in group II (− 13.6%) and (− 13.1%) respectively than in group I (− 1.1%) and (− 1.25%) respectively (P < 0.001).Conclusion: Peribulbar anesthesia harbors a deleterious ischemic effect on the retinal vascular tree of glaucoma patients, which could harmfully affect the vision and the visual field in those vulnerable patients.Keywords: peribulbar, anesthesia, glaucoma, IOP, OCT-A, retinal blood flow

Purpose: To determine the prevalence and characteristics of foveal hypoplasia (also called fovea plana) in patients with Best disease using spectral-domain (SD) optical coherence tomography (OCT) and OCT-angiography (OCT-A). Design: A retrospective observational study including patients diagnosed with Best disease. Subjects and Participants: Fifty-nine eyes of thirty-two patients (fifteen females (46.9%) and seventeen males (53.1%), p = 0.9) diagnosed with Best disease were included. Patients' eyes were categorized into two groups: Eyes with a fovea plana appearance ('FP group') and eyes without fovea plana appearance ('no FP group'), based on the foveal appearance on B-scan SD-OCT. Methods and Main Outcome Measures: Cross-sectional OCT images were assessed for the persistence of inner retinal layers (IRL) and OCT-A was analyzed for the presence of a foveal avascular zone (FAZ), the size of which was determined when applicable. Results: Overall, 16 eyes (27.1%) of 9 patients had a fovea plana appearance ('FP group') with the persistence of IRL, and 43 eyes (72.9%) of 23 patients did not have fovea plana appearance ('no FP group'). Among FP eyes, OCT-A performed in 13 eyes showed bridging vessels through the FAZ in 100% of eyes with OCT-A. Using Thomas classification, 14 out of the 16 eyes with fovea plana (87.5%) had atypical foveal hypoplasia, and the 2 others (12.5%) had a grade 1b fovea plana. Conclusion: In our series, foveal hypoplasia was present in 27.1% of patients with Best disease. OCT-A showed bridging vessels through the FAZ in all eyes. These findings highlight the microvascular changes associated with Best disease, which can be an early sign of the disease in patients with a family history. [ABSTRACT FROM AUTHOR]

Copyright of Acta Medica Croatica is the property of Croatian Academy of Medical Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objectives:This study aimed to evaluate superficial peripapillary vascularization qualitatively and quantitatively in patients with acute non-arteritic anterior ischemic optic neuropathy (NAION) using optical coherence tomography angiography (OCT-A).Materials and Methods:Eleven patients with acute NAION and 14 controls were evaluated retrospectively. Complete ophthalmologic examination with best corrected visual acuity, peripheral visual field test, and disc angiography with OCT-A were performed. Quantitative optic disc perfusion indexes were evaluated by the device with automatically segmentation and qualitative comparison of choroidal, retinal, and en-face peripapillary perfusion angiogram images.Results:In the NAION and control groups, mean age was 57.55±12.34 years and 50.79±4.67 years (p=0.110), the proportion of women was 7/11 (63.6%) and 9/14 (60%), and best corrected visual acuity was 0.95±0.63 and 0.00±0.0 LogMAR (p=0.001), respectively. Visual field defect was present in 10/11 (91%) eyes in the NAION group. In 6 patients, visual field defects were correlated with areas of peripapillary and optic nerve head hypoperfusion. In the patient group, optic nerve head capillary density was significantly decreased (p=0.008) and radial peripapillary capillary density was significantly decreased in all sectors except the inferonasal sector.Conclusion:In our study, we observed that visual field evaluations were partially correlated with optic nerve head and peripapillary capillary perfusion assessed by OCT-A. Being practical and non-invasive, OCT-A is a useful and up-to-date method for evaluating perfusion in NAION.

The prevalence of multiple sclerosis (MS) has been increasing among young people in developing countries over the last years. With the continuous development of new technology, the diagnosis and follow-up of these patients has received new parameters that physicians may use in their practice. This paper reviews the main biomarkers identified through Optical Coherence Tomography Angiography (OCT-A) involved in the development and progression of MS and investigates the role it may have in detecting changes to the central nervous system (CNS).

There has been considerable progress in implicit neural representation to upscale an image to any arbitrary resolution. However, existing methods are based on defining a function to predict the Red, Green and Blue (RGB) value from just four specific loci. Relying on just four loci is insufficient as it leads to losing fine details from the neighboring region(s). We show that by taking into account the semi-local region leads to an improvement in performance. In this paper, we propose applying a new technique called Overlapping Windows on Semi-Local Region (OW-SLR) to an image to obtain any arbitrary resolution by taking the coordinates of the semi-local region around a point in the latent space. This extracted detail is used to predict the RGB value of a point. We illustrate the technique by applying the algorithm to the Optical Coherence Tomography-Angiography (OCT-A) images and show that it can upscale them to random resolution. This technique outperforms the existing state-of-the-art methods when applied to the OCT500 dataset. OW-SLR provides better results for classifying healthy and diseased retinal images such as diabetic retinopathy and normals from the given set of OCT-A images.

Background and Objectives: Early diagnosis of the exudative form of age-related macular degeneration (AMD) is very important for a timely first treatment, which is directly related to the preservation of functional visual acuity over a long period. The goal of this paper was to examine the correlation between the double-layer sign (DLS) and the presence of non-exudative macular neovascularization (MNV). Materials and Methods: Our research included 60 patients with AMD, exudative in one eye and non-exudative in the other eye. We analyzed only the non-exudative form using optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A). The patients were classified into three groups, depending on the duration of the disease (5 years). The onset of the disease was deemed the moment of establishing a diagnosis of exudative AMD in one eye. We defined the presence or absence of a DLS using OCT and the presence of non-exudative MNV using OCT-A, both on 3 × 3 mm and 6 × 6 mm sections. DLS was used as a projection biomarker for non-exudative MNV, with the aim of establishing a rapid diagnosis and achieving early treatment of the disease. Results: We found that there was a statistically significant correlation between the DLS diagnosed using OCT and non-exudative MNV diagnosed by OCT-A for both 3 × 3 mm (p < 0.001) and 6 × 6 mm (p < 0.001) imaging. There was a statistically significant difference between the frequencies of both DLS and MNV in Groups I and III on both 3 × 3 and 6 × 6 mm imaging. A statistically significant difference was also noted in the frequencies of DLS and MNV on 6 × 6 mm imaging, but not on 3 × 3 mm imaging, between Groups I and II. No differences were found between the frequencies of DLS and MNV between Groups II and III. Conclusions: The DLS on OCT can be used as a projection biomarker to assess the presence of a non-exudative MNV.

Purpose: To evaluate the retinal vasculature and vasoreactivity of patients with hypertension (HTN) using spectral domain optical coherence tomography angiography (SD-OCTA). Methods: Patients with and without a diagnosis of HTN were included in this cross-sectional observational study. All eyes were imaged with SD-OCTA using 3 mm × 3 mm and 6 mm × 6 mm centered on both the fovea and optic disk. A second 6 mm × 6 mm scan was taken after a 30 s breath-hold. Vessel density (VD), vessel skeletonized density (VSD), and fractal dimension (FD) were calculated using customized MATLAB scripts. Vessel diameter index (VDI) was obtained by taking the ratio of VD to VSD. Vasoreactivity was measured by subtracting the VD or VSD before and after breath-hold (∆VD, ∆VSD). Results: Twenty-three eyes with HTN (17 patients) and 17 control eyes (15 patients) were included. In the 6 mm × 6 mm angiogram centered on fovea, the superficial capillary plexus (SCP) VD (ß = − 0.029, p = 0.012), VSD (ß = − 0.004, p = 0.043) and the choriocapillaris VD (ß = − 0.021, p = 0.030) were significantly decreased in HTN compared to control eyes. Similarly, FD was decreased in both the SCP (ß = − 0.012, p = 0.013) and choriocapillaris (ß = − 0.009, p = 0.030). In the 3 mm × 3 mm angiogram centered on optic disk, SCP VDI (ß = − 0.364, p = 0.034) was decreased. ∆VD and ∆VSD were both reduced in the DCP (ß = − 0.034, p = 0.032; ß = − 0.013, p = 0.043) and ∆VSD was elevated in the choriocapillaris of HTN eyes (ß = 0.004, p = 0.032). Conclusions: The study used SD-OCTA to show significant differences in the retinal vasculature of hypertensive patients. It was also the first to demonstrate the potential of OCT-A to investigate retinal vascular reactivity in patients with HTN. [ABSTRACT FROM AUTHOR]

Purpose: Optical coherence tomography angiography (OCT-A) has been applied to uveitis and intraocular inflammation since its availability after 2014. The imaging of retinal and choroidal vascularization without the use of dyes was a major development and represented a potentially valuable tool in ocular research. In addition to such use, OCT-A is often put forward as being able to potentially replace invasive methods needing dye injection, such as fluorescein angiography (FA) and indocyanine green angiography (ICGA). The aim of this review was to establish whether OCT-A was sufficiently useful in everyday routine clinical practice to monitor disease evolution and to perform treatment adjustments to the extent that it could reliably replace the standard dye methods. Methods: Selective literature review and analysis of own data and experience. Results: OCT-A is a technologically high-grade imaging modality allowing to analyze retinal circulation in inflammatory diseases of the posterior pole with a high sensitivity useful for research purposes. However, there is no evidence that it reaches equal effectiveness in the routine management of posterior uveitis involving the retina. OCT-A is unable to show leakage. In choriocapillaritis involving pre-capillary vessels, it shows capillary drop-out but does not seem to have an advantage over ICGA except that it can be repeated easily, not being invasive, and so allows a closer follow-up. It is, however, less useful in end-choriocapillary non-perfusion, such as in MEWDS. For choroidal stromal inflammation, OCT-A is ill-suited as it only shows inconsistent secondary circulatory changes produced by choroidal foci. OCT-A seems to be useful in the diagnosis and follow-up of inflammatory chorioneovascularisation (iCNV), although dye exams are more precise in showing the activity of the iCNV. Conclusion: In summary, OCT-A is a very sensitive modality for the retinal circulation in uveitis for research purposes; it is sometimes useful for close follow of choriocapillary drop-out but not in end-capillary non-perfusion. Its use for monitoring purposes in stromal choroiditis, however, is questionable. Its claim to possibly replace classical angiographic work-up for the practical management of posterior uveitis is largely overrated. [ABSTRACT FROM AUTHOR]

To report two cases of acute syphilitic posterior placoid chorioretinitis (ASPPC) with choriocapillaris flow voids that partially resolved with systemic antibiotic treatment. Observational case report with multimodal imaging Two young healthy men suffered an acute monocular loss of vision. Spectral domain optical coherence tomography (SD-OCT) and OCT angiography (OCT-A) revealed outer retinitis with loss of the ellipsoid layer and choriocapillaris flow voids. Systemic work-up revealed syphilis. Upon systemic treatment with antibiotics, the patients recovered their vision and the OCT and OCT-A abnormalities partially resolved. Transient choriocapillaris flow voids characterize ASPPC and may be responsible for the visual loss seen in these patients. [ABSTRACT FROM AUTHOR]

Background: Age-related macular degeneration (AMD) is a progressive, degenerative disease of the central retina. AMD is subdivided into "dry" (atrophic), "wet" (exudative), and neovascular (nAMD) forms. In recent years, the concepts about nAMD changed with the development of optical coherence tomography–angiography (OCT-A) and intravitreal anti-VEGF treatment. The aim of this study was to define the morphologic type of the neovascular membrane (NVM) before treatment with OCT-A and to register vascular remodeling after treatment with anti-VEGF. We also analyzed the relationship between NVM and visual acuity. Methods: The study was retrospective and included 119 patients with newly diagnosed, treatment-naïve nAMD. All the patients underwent full ophthalmic examination and also fluoresceine angiography and optical coherence tomography–angiography (OCT-A). Results: Based on the collected data, we found repetitive regularities. Conclusion: The analysis of our results could be used as prognostic markers for the evolution of the disease and as a basis for new treatment strategies, depending on the naïve NVM morphologic type. [ABSTRACT FROM AUTHOR]

Abstract Purpose The aim of this case control study was to evaluate the prognostic value of automatically quantified retinal vessel tortuosity from fundus images and vessel density from OCT-A in Fabry disease and to evaluate the correlation of these with systemic disease parameters. Methods Automatically quantified perimacular retinal vessel tortuosity (MONA REVA software), acquired by fundus imaging, and perifoveal retinal vessel density, acquired by optic coherence tomography angiography (OCT-A) were compared between 26 FD patients and 26 controls. Gender and FD phenotype were analyzed to the obtained retinovascular data and correlated to the Mainz severity score index (MSSI) and plasma lyso-Gb3. Results Automatically quantified retinal vessel tortuosity indices of FD patients were significantly lower, reflecting an increased vessel tortuosity, compared to controls (p = 0.008). Males with a classical phenotype showed significantly lower retinal vessel tortuosity indices compared to males with an oligosymptomatic phenotype and females with a classical or oligosymptomatic phenotype (p

PurposeOptical coherence tomography angiography (OCT-A) is a noninvasive technology that allows visualization of retinal blood vessels. It is important to determine reproducibility of measurements as low precision can impair its diagnostic capabilities. The purpose of this study is to determine intravisit and intervisit reproducibility of optic nerve head (ONH) and macular vessel density measurements with OCT-A.Patients and methodsFifteen healthy volunteers and 14 glaucoma patients completed 2 OCT-A (AngioVue; Optovue Inc.) scanning sessions on each of 2 separate days to assess intravisit and intervisit reproducibility. A series of ONH and macula scans were acquired at each session. Vessel density (%), the proportion of vessel area over the total measurement area was calculated. Reproducibility was summarized using coefficients of variation (CV) and intraclass correlation coefficients calculated from variance component models.ResultsIn healthy eyes, the CV of intravisit and intervisit global vessel density measures ranged from 1.8% to 3.2% in ONH scans and 2.5% to 9.0% in macular scans. In glaucoma eyes, the CV of intravisit and intervisit global vessel density measures ranged from 2.3% to 4.1% in ONH scans and 3.2% to 7.9% in macular scans. CVs were lower for global than sectorial measures. Global OCT-A ONH intraclass correlation measurements for the retinal nerve fiber layer in healthy eyes were lower (range: 0.65 to 0.85) than in glaucoma eyes (range: 0.89 to 0.94). Scan size did not make large differences in measurement CVs.ConclusionsReproducibility of OCT-A ONH and macula vessel density measurements is good. Moreover, glaucoma patients have sparser vessel density with poorer reproducibility than healthy subjects.

INTRODUCCIÓN: El consumo de tabaco es un factor de riesgo para numerosas enfermedades respiratorias, cardiovasculares y tumorales principalmente pero también lo es para trastornos oculares. OBJETIVO: Comparar mediante angiografía-tomografía de coherencia óptica (OCT) la densidad de los vasos y la densidad de perfusión de la retina superficial y la zona avascular foveal (ZAF) de la retina entre un grupo de pacientes tabaquistas y un grupo de pacientes no tabaquistas. MATERIAL Y MÉTODO: Estudio de tipo prospectivo, analítico, observacional y transversal. Se estudiaron un total de 100 ojos de personas de ambos sexos, entre 20 y 70 años de edad, que asistieron al Instituto Oftalmológico de Córdoba en el período de un año. Se incluyeron pacientes sanos tabaquistas y no tabaquistas, los cuales firmaron consentimiento informado, excluyendo aquellos con alguna comorbilidad sistémica preexistente o con ametropías elevadas. Se les realizó una valoración oftalmológica completa y una angiografía mediante OCT- HD Cirrus Model 5000, registrando los valores de densidad de vasos (mm/mm2) y densidad de perfusión (%) de la retina superficial y el área de la zona avascular foveal (ZAF) (mm2), en un campo de análisis de 3 x 3 mm2. Como análisis estadístico se utilizó el Test MannWhitney y el Test de Kruskal-Wallis considerando p0.5) al comparar entre tabaquistas y no tabaquistas la densidad de vasos central (9.89 ±2.80 vs 9.88 ±3.76) la densidad de vasos periférica (21.16 ±1.57 vs 21.01 ±2.54), la medición de la densidad total de vasos (19.90 ±1.56 vs 19.75 ±2.54), la densidad de perfusión central (17.37 ±4.89 vs 17.20 ±6.50), la densidad de perfusión periférica (38.55±2.50 vs 37.54 ±6.24) y la medición total de perfusión (36.19 ±2.51 vs 35.67 ±4.29). Como así tampoco la Zona Avascular Foveal (0.29 ±0.12 vs 0.30 ±0.11). Se obtuvo un resultado significativo al comparar la capa de fibras nerviosas de la retina entre tabaquistas y no tabaquistas (94.18 ±8.83 vs 99.22 ±8.80). CONCLUSIONES: No se observó que el tabaquismo influye en la vascularización de la retina, pero si hubo una disminución en el espesor de la Capa de Fibras Nerviosas Retiniana (CFNR) siendo importante considerarlo en pacientes que tienen antecedente de glaucoma.

Purpose: To describe a case of late post-surgical sympathetic ophthalmia documented with multimodal imaging. Observations: A 74-year-old male presented to the urgent care of the New York Eye and Ear Infirmary with blurry vision and discomfort in his left eye for three weeks. His vision was 20/50, with intraocular pressure of 13 mmHg, and slit lamp examination was significant for conjunctival congestion, 1+ anterior segment cell and flare, and diffuse keratic precipitates. His right eye was no light perception with a condensed hyphema, intraocular lens and inferonasal tube. His medical history included coronary artery bypass, prostate cancer, hyperlipidemia, and hypertension. His ocular history included blunt trauma to the right eye at age 11 with development of a traumatic macular hole and later rhegmatogenous retinal detachment at age 53, repaired with multiple vitreoretinal procedures. He developed glaucoma in the right eye and was treated with a tube shunt and ultimately transscleral cyclophotocoagulation (TSCPC) 7 years later, 13 years prior to his presentation of the left eye. Dilated fundus examination of his left eye revealed diffuse chorioretinal folds in the macula without any discrete chorioretinal lesions. Ultrasound of the right showed serous macular detachments with scleral thickening. Presumptive diagnosis of sympathetic ophthalmia was made and oral corticosteroid therapy was initiated. Subsequent SD-OCT and en-face OCT-A demonstrated Dalen-Fuchs nodules within the macula underlying areas of resolved serous detachment, after 6 weeks of oral steroids and initiation of immunomodulatory therapy (IMT). Conclusions: Sympathetic ophthalmia may rarely present with very delayed onset, and TSCPC is an uncommon inciting event. These patients may develop serous detachment, choroidal folds and inflammatory nodules identifiable on exam and multimodal imaging, which can resolve when treated appropriately. OCT-A may provide utility in monitoring response to immunosuppressive treatment in these patients.

Abstract Purpose: This study aimed to evaluate responses in retinal tissue by swept source OCT angiography (OCT-A) to hyperoxia after hyperbaric oxygen (HBO2) therapy. Methods: The study was conducted in volunteers who received HBO2 treatment but did not have any eye disease. Patients underwent detailed eye examinations including dilated fundus examination, visual acuity, and refraction before being admitted for HBO2 therapy. Measurements were made before and immediately after HBO2 therapy. Enface images of the retinal vasculature were obtained from the superficial and deep retinal plexus (SP/DP). Quantitative analysis of the vessel density (VD) and foveal avascular zone (FAZ) area was performed. Results: In total, 31 patients (15 female) with healthy retina were included in the study. The mean age was 42.8 years. The mean SP vascular density measurements before HBO2 therapy for the right and left eyes were 15.18 ± 1.2 mm - 1 and 15.01 ± 1.3 mm - 1 , respectively; the measurements after HBO2 therapy for the right and left eyes were 14.34 ± 1.4 mm - 1 and 14.48 ± 1.19 mm - 1 . The mean DP vascular density measurements before HBO2 therapy for the right and left eyes were 16.03 ± 1.69 mm - 1 and 16.1 ± 1.45 mm - 1 , respectively; the measurements after HBO2 therapy for the right and left eyes were 15.02 ± 1.65 mm - 1 and 15.12 ± 2.16 mm - 1 , respectively. Reduction of mean VD in superficial and deep plexus after HBO2 was statistically significant (P = 0.001 and P = 0.000, respectively). Changes in mean FAZ area before and after HBO2 therapy were not statistically significant (P = 0.719). Conclusion: The healthy retina responds to oxygen supersaturation with HBO2 therapy by eventually decreasing vascular density in all layers. These findings may be important for further studies especially related to retina and choroidal oxygenation.

Background: OCT-A is developing as a new non-invasive rapid technique which may replace FFA as a gold standard procedure for diagnosis of DMI. Aim of the Work: Comparison between fluorescein angiography (FA) and optical coherence tomography angiography (OCTA) for imaging of foveal avascular zone (FAZ) in diabetic retinopathy patients (DR) affected and not affected by diabetic macular ischemia, (DMI). Subjects and Methods: In this prospective study, 30 eyes for 30 patients and separated by macular status as 19 eyes with DMI and 11 eyes without DMI instructed to undergo OCT-A scan, FFA. Full ophthalmological examination was done and patients signed their informed consents. Results: Of the 30 patients, 13 females and 17 males with a mean age of 52.63 ± 11.9 years. 17 eyes with DMI and 13 eyes without DMI have underwent full ophthalmological examination, BCVA measurement, FFA and OCT-A. BCVA was higher among eyes without DMI (0.5 ±0.2) as compared with eyes with DMI (0.25 ±0.2). Mean time for FFA was 9.4 ± 3.2 m and for OCT-A was 1.5 ± 0.8 m. OCTA can save time than FFA by 85%. 57% was affected with artifacts with OCT-A while 7% has allergic reactions to flourescien dye. Subjects with DMI presented a mean area on FA and OCTA of 0.85 ± 0.2 mm2 and 0.79± 0.2 mm2, respectively (p < /em> = 0.001). Patients without DMI presented a mean area on FA and OCTA of 0.39 ± 0.1 mm2 and 0.36 ± 0.1 mm2, respectively (p < /em> = 0.01). The ICC for the FAZ measurements between the 2 observers on FA and OCTA was 0.98 and 0.99, respectively. Conclusion: OCTA represents a novel technique to diagnose DMI and it may become an alternative to FA for this purpose.