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Background: Central retinal vein occlusion and cilioretinal artery occlusion are rare but serious ocular conditions that can lead to significant visual impairment. While few cases of central retinal vein occlusion and cilioretinal artery occlusion have been individually reported, concurrent occlusion of both vessels is extremely rare, particularly in younger patients without traditional vascular risk factors. We present the first reported case of simultaneous central retinal vein occlusion and cilioretinal artery occlusion in a young female patient associated with short-term use of progestin-only oral contraceptives (OCPs). Case presentation: A 28-year-old Pakistani female patient presented with sudden, painless vision loss in the left eye, 3 hours prior to her arrival at the ophthalmology clinic. Visual acuity in the affected eye was limited to counting fingers at a distance of 0.5 feet, with a best-corrected visual acuity of 6/6 in the right eye. Fundoscopic examination revealed optic disc edema, preretinal hemorrhages, venous dilation, and cotton wool spots consistent with central retinal vein occlusion, alongside ischemic changes in the foveal region suggestive of cilioretinal artery occlusion. On the basis of clinical examination, fundus fluorescein angiography, and optical coherence tomography findings, the patient was diagnosed with concurrent central retinal vein occlusion and cilioretinal artery occlusion. Systemic workup to rule out thrombophilia and other vascular risks was negative. She was treated with acetazolamide, aspirin, and ocular massage, alongside a dorzolamide-timolol combination for intraocular pressure control. Six weeks later, panretinal photocoagulation was performed to prevent neovascular complications. Conclusions: This case highlights the rare presentation of simultaneous central retinal vein occlusion and cilioretinal artery occlusion, likely precipitated by short-term progestin-only OCP use in a young female. The absence of other vascular risk factors emphasizes the potential thrombotic risk associated with hormonal contraception, even in brief courses. Careful consideration should be given to contraceptive choice, and ophthalmologic monitoring is recommended for early detection and intervention in at-risk patients. [ABSTRACT FROM AUTHOR]

Automatic classification of retinal arteries and veins (A/V) is crucial for assisting clinicians in diagnosing cardiovascular and eye diseases. Deep learning models have been widely employed for A/V classification, achieving remarkable performance. However, two primary challenges persist: vessel discontinuity and A/V confusion. To address the vessel discontinuity challenge, we have designed a multi-scale convolution block (MCB) that combines square and strip convolutions. This design enhances the segmentation of tiny vessels by capturing more discriminative vessel features, effectively resolving the issue of vessel discontinuity. Meanwhile, to tackle the A/V confusion challenge, we propose a dense color-invariant feature learning (DCIFL) method to improve the model's robustness to color variations in retinal images. Specifically, DCIFL uses KL divergences to align the distributions of both latent representations and prediction maps of the raw input image and its color-transformed counterpart. By integrating MCB and DCIFL, we introduce EAV-Net, an efficient model for retinal A/V classification. The proposed method has been tested on three publicly available datasets, achieving accuracies of 96.59%, 97.28%, and 99.34% on the AV-DRIVE, WIDE, and HRF datasets, respectively. These results demonstrate the superiority of our approach in outperforming state-of-the-art methods. Our code will be released at https://github.com/guomugong/EAV-Net. [ABSTRACT FROM AUTHOR]

Background: Gestational diabetes mellitus (GDM) is a temporary metabolic disorder in which small retinal vessels may have experience subtle changes before clinical lesions of the fundus retina appear. An innovative artificial intelligence image processing technology was applied to locate and analyze the small retinal vessel morphology and accurately evaluate the changes of the small retinal vessels in GDM patients and pregnant women with normal blood glucose and non-pregnant women with normal blood glucose. Methods: The subjects were divided into three groups:GDM group, pregnant control group (PC), and normal control group (NC). Use optical coherence tomography angiography (OCTA) to collect OCT images of subjects,and perform quantitative identification and analysis of retinal vessel parameters based on artificial intelligence measurement software integrated the prior knowledge supervised edge-aware multi-task network (PKSEA-Net): Retinal arteriolar lumen diameter (RALD), retinal arteriolar outer diameter (RAOD), retinal venular lumen diameter (RVLD),retinal venular outer diameter (RVOD),arterial wall thickness (AWT),venular wall thickness (VWT),arterial wall to lumen ratio (AWLR),venular wall to lumen ratio (VWLR),arterial wall cross-sectional area (AWCSA),venular wall cross-sectional area (VWCSA), arteriovenous ratio (AVR). Results: This study revealed significant differences in RVOD, RVLD, VWT, VWCSA and AVR between the GDM group and the PC group (p = 0.005, p < 0.027, p = 0.008, p = 0.001, p = 0.022), significant differences in RVOD, RVLD, VWT, VWCSA and AVR between the GDM group and the NC group (p < 0.001, p = 0.001, p < 0.001, p < 0.001, p = 0.001). In GDM group, RVOD, RVLD, VWT and VWCSA increased, while AVR decreased. There were no significant differences in RVOD, RVLD, VWT, VWCSA and AVR between PC group and NC group (p = 0.139, p = 0.263, p = 0.107, p = 0.059, p = 0.218), and no significant differences in VWLR among the three groups (p > 0.05). No significant difference was observed in retinal artery vascular parameters (RAOD, RALD, AWT, AWLR, AWCSA) across the three groups (p > 0.05). Conclusion: There were increases in RVOD, RVLD, VWT, and VWCSA, decrease in AVR in patients with GDM. However, no significant difference of retinal vascular parameters was shown between normal pregnant women and normal non-pregnant women. PKSEA-Net can assist to identify changes in retinal vascular morphology and diagnose micro-vascular lesion early in normal pregnant women and high-risk groups of GDM. [ABSTRACT FROM AUTHOR]

Objective: To examine the relationship between retinal vascular geometry and silent brain infarction (SBI) in the Chinese population. Methods: We conducted a cross-sectional study that retrospectively analyzed the fundus photographs, MRI and other clinical data of 227 SBIs and 227 controls who visited Shanghai Health And Medical Center for physical examination. The retinal vessel fractal dimension (FD), retinal artery fractal dimension (FDa), retinal vein fractal dimension (FDv), central retinal artery diameter in the region from 0.5 ~ 1.0 disc diameter (DD) from the disc margin (CRAEB), central retinal artery diameter in the region from 1.0 ~ 2.0 DD from the disc margin (CRAEC), central retinal vein diameter in the region from 0.5 ~ 1.0 DD from the disc margin (CRVEB), central retinal vein diameter in the region from 1.0 ~ 2.0 DD from the disc margin (CRVEC), retinal arteriovenous diameter ratio in the region from 0.5 ~ 1.0 DD from the disc margin (AVRB), and retinal arteriovenous diameter ratio in the region from 1.0 ~ 2.0 DD from the disc margin (AVRC) were accessed by the Singapore "I" Vessel Assessment (SIVA) software. Results: FD, FDa, FDv, CRAEB, CRAEC, CRVEB, CRVEC and AVRB in SBI subjects were 1.25 (1.21–1.28), 1.11 (1.08–1.14), 1.09 (1.06–1.13), 168.78 ± 19.39, 163.55 ± 18.97, 235.77 (222.64-254.08), 224.39 ± 23.29, 0.72 ± 0.06, respectively, significantly lower than those of control subjects [1.30 (1.28–1.32), 1.15 (1.13–1.18), 1.14 (1.12–1.16), 196.81 ± 27.94, 183.81 ± 25.46, 273.03 (247.59–296.30), 249.59 ± 32.03, and 0.73 ± 0.08]. Logistic regression results showed that higher FD (OR, 0.04), FDa (OR, 0.07), FDv (OR, 0.06), CRAEB (OR, 0.02), CRAEC (OR, 0.04), CRVEB (OR, 0.03), CRVEC (OR, 0.06), and AVRB (OR, 0.55) were associated with a lower of SBI. There was no significant difference in AVRC between the two groups. Conclusion: Our study shows the association between retinal vascular geometry and SBI, and the results may provide new biomarkers for the early detection of SBI. [ABSTRACT FROM AUTHOR]

Background/Objectives: Cardiovascular diseases are a leading cause of death, and psychosocial stress is considered a contributing factor to these issues. With the rising number of heart surgeries, proper rehabilitation post-surgery is essential. Previous studies have demonstrated the positive impact of yoga and transcendental meditation on the cardiovascular system. This pilot study aimed to investigate the effects of yoga and transcendental meditation on retinal microcirculation in cardiac patients before (admission), after (discharge), and following (3 weeks after discharge) rehabilitation. Methods: This study examined changes in retinal microcirculation in three rehabilitation groups of patients after heart surgery. The control group received standard exercise therapy, while the meditation group incorporated 20 min of meditation, and the yoga group incorporated 20 min of yoga practice, twice per day for the duration of four weeks of rehabilitation. Retinal images were captured using a non-mydriatic digital retinal camera (Canon CR-2, Canon Medical Systems Europe B.V., Netherlands), and the microcirculation parameters central retinal artery equivalent, central retinal vein equivalent, and artery-to-vein ratio were analyzed using MONA REVA software ((version 2.1.1), VITO, Mol, Belgium). Repeated measures ANOVA was performed to evaluate differences between the three groups in the course of rehabilitation. Results: None of the parameters revealed significant differences in retinal microcirculation between the three rehabilitation groups. Conclusions: The study evaluating changes in retinal microcirculation, as an indicator of central circulation in cardiac patients undergoing rehabilitation, did not observe any significant changes. As yoga and meditation are underestimated approaches in cardiac rehabilitation, this pilot study acts as a basis for providing preliminary information for future studies to encourage the research community to fill the gap in this area. [ABSTRACT FROM AUTHOR]

The article "What is Occluding Our Understanding of Retinal Vein Occlusion?" published in Ophthalmology & Therapy discusses the rising prevalence of retinal vein occlusion (RVO) and the complexity of its pathogenesis. It emphasizes the need to address unmet needs within the RVO patient journey by leveraging advancements in imaging, biomarkers, and novel treatments. The text highlights gaps in understanding the pathogenesis, risk factors, and treatment strategies for RVO, calling for individualized care and improved diagnostic investigations. The article also discusses recent clinical trials investigating faricimab and the potential of dual inhibition therapy in improving outcomes for patients with RVO. [Extracted from the article]

Purpose: Neurovascular coupling impairment and inner retinal layer thinning are early detectable retinal changes in diabetes, and both worsen during progression of diabetic retinopathy (DR). However, direct interactions between these features have not been investigated so far. Therefore, we aimed to analyze associations between the retinal functional hyperemic response to light stimulation and the thickness of individual neuroretinal layers in eyes with early non-proliferative DR. Methods: Thirty patients with type 1 diabetes featuring mild (n = 15) or moderate (n = 15) non-proliferative DR and 14 healthy subjects were included in this cross-sectional study. Retinal vessel diameters were measured before and during illumination with flickering light using a dynamic vessel analyzer. Individual layer thickness in the macula was analyzed from spectral domain optical coherence tomography. Results: Flicker light-induced vessel dilation was significantly reduced in patients compared to healthy controls (veins: 3.0% vs. 6.1%, p < 0.001; arteries: 1.3% vs. 5.1%, p = 0.005). Univariately, the response in retinal veins of diabetes patients correlated significantly with ganglion cell layer (GCL) thickness (r = 0.46, p = 0.010), and negatively with hemoglobin A1c (HbA1c) levels (r=-0.41, p = 0.023) and age (r=-0.38, p = 0.037), but not with baseline diameters, glucose levels, or diabetes duration. In a multiple regression model only GCL thickness (p = 0.017, β = 0.42) and HbA1c (p = 0.045, β=-0.35) remained significantly associated with the vascular flicker light response. Conclusion: The results indicate that thinner GCL and worse glycemic control both contribute to reduced retinal neurovascular coupling in patients with clinical signs of DR. Progression of neurovascular dysfunction in DR might be related to structural degeneration of the neurovascular complex in the inner retina. Key message: What is known: • Neurovascular coupling dysfunction and neurodegeneration in the inner retina are early features in eyes of diabetes patients, and both worsen during progression of diabetic retinopathy. However, direct interactions between these changes have not been investigated so far. What is new: • Our study shows that in patients with early diabetic retinopathy the reduced functional hyperemic response to flicker light stimulation correlates significantly with inner retinal layer thickness, and concurrently with worse glycemic control. • This demonstrates for the first time that retinal neurodegeneration may be an important contributor to the advancing disturbance of neurovascular coupling in eyes with clinically established diabetic retinopathy. [ABSTRACT FROM AUTHOR]

Veins have emerged as the origin of all other endothelial cell subtypes needed to expand vascular networks during developmental and pathological neoangiogenesis. Here, we uncover the role of the angioneurin Fibronectin Leucine Rich Transmembrane protein (FLRT) 2 in central nervous system (CNS) vascular development in the mouse. Early postnatal FLRT2 deletion reveals specific defects in retinal veins, impacting endothelial cell proliferation, sprouting and polarity that result in reduced tip cells at the vascular front. FLRT2 interacts with VE-cadherin and together with the endocytic adaptor protein Numb contribute to the modulation of adherens junction morphology in both retina and cerebral cortex in vivo. Utilizing expansion microscopy, we visualize the altered dynamic distribution of VE-cadherin in tissue of FLRT2 endothelial mutants. Additionally, FLRT2 in cortical vessels regulates the crosstalk between adherens and tight junctions, influencing blood-brain barrier development. Our findings position FLRT2 as a vein-specific regulator of CNS vascular development. Llao-Cid et al find FLRT2 (Fibronectin Leucine Rich Transmembrane protein) is present in the veins and capillaries of the central nervous system, where it regulates vascular development and the formation of the blood-brain barrier by influencing VE-cadherin turnover. [ABSTRACT FROM AUTHOR]

Introduction: To investigate the impact of posterior vitreous detachment (PVD) on the risk of developing neovascular glaucoma (NVG) in eyes with occlusions of the retinal artery (RAO) or retinal vein (RVO). Methods: Single-center retrospective case-control study of adults with a history of RVO/RAO. Cases (N = 101) who developed NVG were age and sex matched 1:2 to controls who did not develop NVG (N = 202). Multivariable logistic regression was used to estimate the association between history of PVD and risk of NVG while controlling for other related demographic or clinical factors. Results: In initial bivariate analyses, there was no difference in risk of NVG based on eye, lens status, hypertension, history of panretinal photocoagulation (PRP), or retinal surgery (all p > 0.10), a borderline difference based on diabetic retinopathy (DR) (p = 0.06) and prior anti-vascular endothelial growth factor (anti-VEGF) treatment (p = 0.08), and a significant difference based on race/ethnicity, type of vascular event, and PVD status (all p < 0.05). In the final multivariable model, patients without PVD were significantly more likely to develop NVG (OR = 3.07, p = 0.0001) independent of the other covariates. Risk of NVG was greater in those with DR (OR = 1.98, p = 0.0440) and in those with central RVO vs. branch RVO/hemiretinal RVO (OR = 5.77, p < 0.0001). Non-White/Non-Hispanics (OR = 2.56, p = 0.0051) and Hispanics (OR = 3.65, p = 0.0288) were more likely than White patients to develop NVG. Conclusions: Progression to NVG after retinal vascular occlusion is more likely in Non-White/Hispanic patients, those with concomitant DR, and those with CRVO/CRAO. The absence of PVD increases the risk for NVG. Further studies are necessary to understand this relationship. [ABSTRACT FROM AUTHOR]

Aims: To investigate the changes in retinal microvasculature by contemporary imaging techniques during episodes of acute decompensated heart failure (ADHF) and following recompensation compared to age‐matched controls without known cardiac or retinal disease. Methods and results: Adult patients hospitalized with a primary diagnosis of ADHF, regardless of left ventricular ejection fraction (LVEF) and treated with a minimum dose of 40 mg of intravenous furosemide or equivalent were included. Transthoracic echocardiography was conducted in all patients. Eye examinations were performed out within the initial 24 h after admission and after recompensation before discharge. All eyes underwent a general examination, including a best corrected visual acuity test, dilated fundoscopy, spectral‐domain optical coherence tomography (OCT) as well as OCT angiography (OCT‐A). In addition, 40 participants without documented cardiac or retinal diseases served as controls. Forty patients with ADHF (mean age 78.9 ± 8.8 years; 32% female) with a mean LVEF of 43 ± 12.8% were included. All patients were treated with intravenous diuretics for a median of 4.3 ± 2.8 days. There was a significant reduction in N‐terminal pro‐B‐type natriuretic peptide from baseline up to discharge (10 396 [interquartile range 6410] vs. 6380 [interquartile range 3933] pg/ml, p ≤ 0.001) and inferior vena cava diameters (2.13 ± 0.4 vs. 1.63 ± 0.3 cm, p = 0.003). Compared to the control group, patients with ADHF showed on admission impaired visual acuity (0.15 ± 0.1 vs. 0.35 ± 0.1 logMAR, p < 0.001), reduced macular vessel density (18.0 ± 1.9 vs. 14.3 ± 3.6 mm/mm2, p < 0.001) and perfusion density (42.6 ± 3.2 vs. 35.2 ± 9.7%, p < 0.001). After recompensation, the mean overall vessel density and mean overall perfusion density were markedly increased at discharge (14.3 ± 3.6 vs. 19.7 ± 2.6 mm/mm2, p = 0.001, and 35.2 ± 9.7 vs. 39.2 ± 6.5%, p = 0.005, respectively). The mean diameter of the superior temporal retinal vein at admission was significantly larger compared to the control group (136 ± 19 vs. 124 ± 22 μm, p = 0.008) and decreased significantly to 122 ± 15 μm at discharge (p < 0.001). Conclusion: This analysis revealed a remarkable reversible change in retinal microvasculature after ADHF. This could provide a valuable evidence for use of OCT‐A in the assessment of overall microperfusion and haemodynamic status in patients with acute heart failure. [ABSTRACT FROM AUTHOR]

Retinal vein occlusion (RVO) and cerebrovascular disease share common risk factors and may be independently associated; however, the strength and nature of this association remain unclear. We conducted a systematic review and meta-analysis, informed by studies from PubMed, Scopus, EMBASE, Web of Science, and Google Scholar until January 6, 2024, aimed to clarify this relationship. Eligible studies included cohorts observing stroke incidence in RVO patients for over a year. Pooled effect estimates were calculated using random-effects models, with subgroup analyses evaluating associations between RVO types (central and branch) and stroke subtypes (ischemic and hemorrhagic). Ten cohort studies with a total of 428,650 participants (86,299 RVO patients) were included. Compared to controls, RVO patients exhibited a significantly increased risk of stroke (pooled risk ratio [RR]=1.38, 95 % confidence interval (95 %CI)=1.34–1.41). Subgroup analyses indicated elevated risk for both ischemic (RR=1.37, 95 %CI=1.32–1.42) and hemorrhagic (RR=1.55, 95 %CI=1.08–2.22) strokes in RVO patients. Additionally, both central (RR=1.50, 95 %CI=1.27–1.78) and branch (RR=1.41, 95 %CI=1.32–1.50) RVO were associated with stroke risk. Sensitivity analyses confirmed consistent results across various criteria, and funnel plots indicated no publication bias. RVO significantly increases the risk of both ischemic and hemorrhagic stroke, regardless of RVO type, suggesting a strong independent association between these conditions. [ABSTRACT FROM AUTHOR]

Clinical relevance: Central retinal artery occlusion (CRAO) is an ophthalmic emergency with a poor prognosis. Several initial CRAO presentation factors can influence the final visual outcome. Fluorescein angiography filling of retinal vessels in CRAO has not been studied in great detail. Background: The aim of this paper is to study the aberrant filling of the retinal vessels on fluorescein angiography in patients with CRAO and understand its clinical relevance. Methods: Cases of CRAO diagnosed between June 2017 and May 2022 and who had undergone a fundus fluorescein angiography were included. Comparisons were made between the cases with and without aberrant filling of the retinal vessel. Results: Twenty-two eyes of 22 patients (14 males and 8 females) with CRAO underwent fluorescein angiography. Ages of the patients ranged from 18 to 73 years, while time interval between development of acute onset vision problems and presentation to the retinal clinic ranged from a minimum of 1 day to a maximum of 30 days. Snellen visual acuity at presentation ranged from perception of light (PL +) to 6/6. On fluorescein angiography, aberrant flow of the fluorescein dye into the retinal vein was observed in four of the 22 (18%) eyes with CRAO. All these cases showed a patient's temporal cilioretinal artery. The cases with aberrant filling of the retinal vessels showed a better presenting visual acuity (6/6–6/60), lesser severity of inner retinal damage and a better final visual acuity (6/6–6/60) compared to CRAO cases without aberrant filling. Conclusion: Aberrant filling of the retinal vein can be seen on fluorescein angiography in eyes with CRAO and a patent temporal cilioretinal artery. Such eyes with aberrant retinal vessel filling have a better visual prognosis. [ABSTRACT FROM AUTHOR]

Lipoprotein(a) [Lp(a)], a low-density lipoprotein-like particle containing a highly polymorphic apolipoprotein(a) [apo(a)] homologous in > 80% to plasminogen, was identified as a genetically determined independent risk factor for cardiovascular disease. Elevated Lp(a) levels, found in about 20% of Europeans, are strongly linked to higher rates of myocardial infarction, major adverse cardiac events, accelerated plaque progression, ischemic stroke (especially in younger adults), and calcific aortic valve disease. However, its role in venous thromboembolism, including atypical locations like cerebral and retinal vein thrombosis, remains controversial despite several shared mechanisms underlying arterial and venous thromboembolism. The most robust evidence supports antifibrinolytic properties of elevated Lp(a), particularly smaller apo(a) isoforms, which inhibit plasminogen activation mainly by interacting with the tissue-type plasminogen activator, plasminogen, and fibrin. Other prothrombotic mechanisms include increased synthesis of plasminogen activator inhibitor (PAI-1), formation of denser fibrin networks composed of thinner fibers, less susceptible to lysis, increased platelet activation, enhanced oxidation of phospholipids leading to a low-grade proinflammatory state, upregulated tissue factor expression, and suppression of tissue factor pathway inhibitor. Targeted Lp(a) lowering therapies are currently being tested in randomized clinical trials and could potentially have clinically relevant antithrombotic effects, evidenced by the reduced risk of thromboembolism. This review summarizes the available data on the prothrombotic and antifibrinolytic actions of Lp(a), along with clinical evidence for the increased risk of thromboembolic events related to elevated Lp(a). It also introduces new concepts to explain discrepant clinical results regarding venous events, highlighting the impact of oxidized phospholipids on a prothrombotic state under conditions of high Lp(a). [ABSTRACT FROM AUTHOR]

A 51‐year‐old male underwent vitrectomy with retrobulbar anesthesia for retinal detachment. Post surgery, he experienced systemic hypotension which normalized after 3 h. The day after, he complained of a central scotoma in the operated eye. Intraocular pressure was normal, but fundus examination revealed hemorrhages and whitening along the papillomacular bundle and macula, with additional whitening in the upper midperipheral region. Multimodal imaging confirmed branch retinal vein, artery, and cilioretinal artery occlusion. Further examination revealed mild‐to‐moderate obstructive sleep apnea syndrome. Vascular occlusions are potential complications of vitreoretinal surgery, warranting thorough preoperative assessment for underlying risk factors, even if causative mechanism is still unknown. [ABSTRACT FROM AUTHOR]

Purpose: To present a novel optical model explaining why the vast majority of patients with Asteroid Hyalosis (AH) do not perceive any floaters. This changes our understanding of floater perception and undermines the operation mode of YAG laser vitreolysis. Methods: Relying on a previously published model of floater perception based on astronomical equations of a solar eclipse, and on ultrasound images of the vitreous in three eyes with AH, we explain why such patients do not perceive floaters in spite of opaque bodies filling their entire vitreous, to the point of, in severe cases of AH, obscuring the fundus view during ophthalmoscopy. Main outcome measures: Developing an optical model of light rays that can quantify the maximal distance upon which a vitreous floater or opacity will cast a shadow on the retina. Results: Calculations using the proposed model demonstrated that with a 3 mm pupil, for a floater located between 1.5 mm and 2 mm from the retina, its shortest diameter must be > 215 microns and > 286 microns, respectively, to be perceived. Since AH floaters, based on ultrasound imaging, do not exist in the most peripheral 1.5 mm of the vitreous, it becomes understandable why these patients are asymptomatic. Conclusions: Based on the proposed model and our findings, we deduced that even large, degenerative floaters whose width is usually narrower than a large retinal vein (125 microns), must be located very close to the retina and hence are not the floaters that are aimed at when performing YAG laser vitreolysis. We speculate that in successful cases, YAG vitreolysis works by a different mechanism, most likely a shock wave that displaces floaters further away from the retina. Hence, vitreolysis might not necessarily require the laser be aimed at the floaters, as symptomatic floaters may be located in the outer 1.5–2.0 mm of the vitreous body, a very risky zone for YAG laser shots. [ABSTRACT FROM AUTHOR]

Background: Chronic myeloid leukemia (CML) can manifest ocular complications stemming from hematologic irregularities or direct infiltration of neoplastic cells. This article details the case of a patient with newly diagnosed CML exhibiting elevated platelet counts (PLT) who developed panuveitis accompanied by retinal vascular occlusion. Case presentation: A 52-year-old woman experienced a notable decline in vision in her left eye over a 2-week period. Classical anterior uveitis, vitreous cavity opacity, optic nerve edema, and retinal vascular obstruction were observed. The right eye exhibited papilledema and retinal vein tortuosity. Despite admission, the condition of both eyes deteriorated, accompanied by a continuous increase in PLT. She was diagnosed with CML based on bone marrow biopsy and chromosomal examination. Following platelet apheresis therapy and chemotherapy, the condition of her right eye significantly improved, but the left eye's condition remained irreversible. Conclusions: This is a rare case of newly diagnosed CML presenting with diverse ocular manifestations in both eyes. The disparate outcomes in eyes with varying lesion stages underscore the importance of prompt diagnosis. [ABSTRACT FROM AUTHOR]

Purpose: To assess the long-term outcomes in the management of macular edema (ME) secondary to retinal vein occlusion (RVO). Materials and methods: This study comprised 25 patients with branch RVO (BRVO) and 30 patients with central RVO (CRVO). Initial treatment consisted of monthly anti-VEGF injections for 6 months in BRVO and 6 to 12 months in CRVO. Subsequent treatment for patients who did not meet stability criteria was based on response to treatment. Results: The mean follow-up time was 46 months. The mean number of injections per patient in the first year was 7.7 for BRVO and 9.2 for CRVO and decreased dramatically in the years thereafter. About 67% of the eyes received anti-VEGF agents only. At the final visit, for patients with BRVO and CRVO,respectively, central subfield thickness had decreased -167 and -280 µm, and visual acuity gain gain was 11.5 and 19.0 letters. ME had resolved in 84% of patients with BRVO and 67% of patients with CRVO. Older age (P<0.001),diabetes (P=0.01) and persistence of ME (P<0.001) limited the visual improvement in BRVO, and retinal ischemia (P<0.001) and severe disorganization of the retinal inner layers (P<0.001) after treatment limited the visual improvement in CRVO. Conclusion: Initiating early intensive intervention with anti-VEGF during the early phase of ME can suppress recurrence in chronic phase. In the chronic phase, when the disease becomes resistant to anti-VEGF therapy, scatter laser photocoagulation may decrease the treatment burden in ischemic BRVO, and dexamethasone implant may improve cost-effectiveness in both BRVO and CRVO. [ABSTRACT FROM AUTHOR]

Introduction: Branch retinal vein occlusion (BRVO) is a leading cause of vision impairment globally and the second most common retinal vascular disease leading to blindness. Affecting over 20 million people worldwide, the prevalence of BRVO is expected to increase with the aging population. Branch retinal vein occlusion occurs due to the obstruction of small veins draining blood from the retina, leading to hemorrhages, fluid leakage and retinal damage. Its pathogenesis involves a complex interplay of ocular conditions and genetic predispositions. Methods: A comprehensive literature search was conducted using PubMed and Google Scholar for articles published between January 2010 and January 2024. The search terms included "retinal vein occlusion", "BRVO" and "risk factors." After initial screening of 642 articles, non-English articles, animal studies and in vitro models were excluded. In total, 63 articles were analyzed for ocular and genetic risk factors associated with BRVO. Results: Ocular risk factors for BRVO include glaucoma, short axial length and optic disc drusen. Elevated intraocular pressure in glaucoma can compress retinal veins, while short axial length increases the likelihood of venous compression. Optic disc drusen cause vascular anomalies that heighten BRVO risk. Genetic polymorphisms affecting coagulation, endothelial function, inflammation and oxidative stress, such as MTHFR C677T and Factor V Leiden, also influence BRVO susceptibility. Familial clustering and genetic variations in inflammatory pathways further contribute to the risk. Conclusion: The significant impact of BRVO on vision health underscores the need for comprehensive strategies for early detection, prevention and treatment. Understanding the ocular and genetic risk factors is crucial for developing personalized treatment and effective public health initiatives. Ongoing research into genetic and molecular mechanisms will enhance management approaches and improve patient outcomes. [ABSTRACT FROM AUTHOR]

BackgroundGestational diabetes mellitus (GDM) is a temporary metabolic disorder in which small retinal vessels may have experience subtle changes before clinical lesions of the fundus retina appear. An innovative artificial intelligence image processing technology was applied to locate and analyze the small retinal vessel morphology and accurately evaluate the changes of the small retinal vessels in GDM patients and pregnant women with normal blood glucose and non-pregnant women with normal blood glucose.MethodsThe subjects were divided into three groups:GDM group, pregnant control group (PC), and normal control group (NC). Use optical coherence tomography angiography (OCTA) to collect OCT images of subjects,and perform quantitative identification and analysis of retinal vessel parameters based on artificial intelligence measurement software integrated the prior knowledge supervised edge-aware multi-task network (PKSEA-Net): Retinal arteriolar lumen diameter (RALD), retinal arteriolar outer diameter (RAOD), retinal venular lumen diameter (RVLD),retinal venular outer diameter (RVOD),arterial wall thickness (AWT),venular wall thickness (VWT),arterial wall to lumen ratio (AWLR),venular wall to lumen ratio (VWLR),arterial wall cross-sectional area (AWCSA),venular wall cross-sectional area (VWCSA), arteriovenous ratio (AVR).ResultsThis study revealed significant differences in RVOD, RVLD, VWT, VWCSA and AVR between the GDM group and the PC group (p = 0.005, p < 0.027, p = 0.008, p = 0.001, p = 0.022), significant differences in RVOD, RVLD, VWT, VWCSA and AVR between the GDM group and the NC group (p < 0.001, p = 0.001, p < 0.001, p < 0.001, p = 0.001). In GDM group, RVOD, RVLD, VWT and VWCSA increased, while AVR decreased. There were no significant differences in RVOD, RVLD, VWT, VWCSA and AVR between PC group and NC group (p = 0.139, p = 0.263, p = 0.107, p = 0.059, p = 0.218), and no significant differences in VWLR among the three groups (p > 0.05). No significant difference was observed in retinal artery vascular parameters (RAOD, RALD, AWT, AWLR, AWCSA) across the three groups (p > 0.05).ConclusionThere were increases in RVOD, RVLD, VWT, and VWCSA, decrease in AVR in patients with GDM. However, no significant difference of retinal vascular parameters was shown between normal pregnant women and normal non-pregnant women. PKSEA-Net can assist to identify changes in retinal vascular morphology and diagnose micro-vascular lesion early in normal pregnant women and high-risk groups of GDM.

Automatic segmentation of the fundus retinal vessels and accurate classification of the arterial and venous vessels play an important role in clinical diagnosis. This article proposes a fundus retinal vascular segmentation and arteriovenous classification network that combines the adversarial training and attention mechanism to address the issues of fundus retinal arteriovenous classification error and ambiguous segmentation of fine blood vessels. It consists of three core components: discriminator, generator, and segmenter. In order to address the domain shift issue, U‐Net is employed as a discriminator, and data samples for arterial and venous vessels are generated with a generator using an unsupervised domain adaption (UDA) approach. The classification of retinal arterial and venous vessels (A/V) as well as the segmentation of fine vessels is improved by adding a self‐attention mechanism to improve attention to vessel edge features and the terminal fine vessels. Non‐strided convolution and non‐pooled downsampling methods are also used to avoid losing fine‐grained information and learning less effective feature representations. The performance of multi‐class blood vessel segmentation is as follows, per test results on the DRIVE dataset: F1‐score (F1) has a value of 0.7496 and an accuracy of 0.9820. The accuracy of A/V categorization has increased by 1.35% when compared to AU‐Net. The outcomes demonstrate that by enhancing the baseline U‐Net, the strategy we suggested enhances the automated classification and segmentation of blood vessels. [ABSTRACT FROM AUTHOR]

Central retinal vein occlusion typically manifests in older individuals with underlying systemic pathology, leading to a spectrum of symptoms ranging from blurred vision to complete vision loss. While odontogenic infections are recognized for causing complications affecting the eye and vision, their potential role as an etiological factor in cases of sudden vision impairment merits consideration. This article presents a case involving central retinal vein thrombosis, wherein resolution was achieved through a combination of ophthalmic therapy and the surgical removal of a concurrently existing large inflamed odontogenic cyst located in the ipsilateral hemimaxilla. This case underscores the importance of recognizing odontogenic factors in the assessment of sudden vision impairment and the efficacy of a multidisciplinary therapeutic approach. [ABSTRACT FROM AUTHOR]

Purpose: This study is to investigate the increase in retinal venous pressure (RVP) induced by a stepwise increase in airway pressure (AirP) using the new IOPstim method, which is designed to artificially increase the intraocular pressure (IOP) and thus to stimulate vascular pulsation. Methods: Twenty-eight healthy subjects were examined in the left eye. The RVP was measured at baseline and at four different levels of AirP (10, 20, 30, and 40 mmHg) using the new IOPstim method: a half balloon of 8 mm diameter is inflated laterally to the cornea under observation of the central retinal vein. As soon as the vein pulsates at a certain AirP level, the IOP is measured with a commercially available tonometer, which then corresponds to the RVP. Results: Spontaneous venous pulsation was observed in all study participants. The mean RVP values at baseline and at the AirP levels of 10, 20, 30, and 40 mmHg were 17.6 ± 2.8 mmHg; 20.1 ± 3.0 mmHg; 22.1 ± 3.5 mmHg; 24.3 ± 3.7 mmHg, and 26.6 ± 4.2 mmHg, respectively. The mean RVP values of each AirP level were statistically significantly different from each other in pairwise comparison. In a linear mixed model, the effect of AirP on RVP was highly significant (p < 0.001). In the model, a 10-mmHg increase in AirP resulted in a linear increase in RVP of 2.2 mmHg. Conclusion: An increase in AirP was accompanied by a linear increase in RVP. The influence of AirP on RVP, and thus on retinal perfusion pressure during the Valsalva maneuver, is less than was assumed based on previous studies in which contact lens dynamometry was used. [ABSTRACT FROM AUTHOR]

Retinal vein occlusion (RVO) is a significant cause of vision loss, characterized by the occlusion of retinal veins, leading to conditions such as central retinal vein occlusion (CRVO) and branch retinal vein occlusion (BRVO). Macular edema (ME), a prevalent consequence of RVO, is the primary cause of vision impairment in affected patients. Anti-VEGF agents have become the standard treatment, showing efficacy in improving visual acuity (VA) and reducing ME. However, a subset of patients exhibit a suboptimal response to anti-VEGF therapy, necessitating alternative treatments. Corticosteroids, which address inflammatory pathways implicated in ME, have shown promise, particularly in cases resistant to anti-VEGF. This review aims to identify biomarkers that predict treatment response to corticosteroids in RVO-associated ME, utilizing multimodal imaging and cytokine assessments. Baseline imaging, including SD-OCT and OCT-A, is essential for evaluating biomarkers like hyperreflective foci (HRF), serous retinal detachment (SRF), and central retinal thickness (CRT). Elevated cytokine levels, such as IL-6 and MCP-1, correlate with ME severity and poor anti-VEGF response. Early identification of these biomarkers can guide timely transitions to corticosteroid therapy, potentially enhancing treatment outcomes. The practical conclusion of this review is that integrating biomarker assessment into clinical practice enables personalized treatment decisions, allowing for earlier and more effective management of RVO-associated ME by transitioning patients to corticosteroid therapy when anti-VEGF agents are insufficient. Advanced diagnostics and machine learning may further refine personalized treatment strategies, improving the management of RVO-associated ME. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Modern Laboratory Medicine is the property of Journal of Modern Laboratory Medicine Editorial Department 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.)

Purpose: To investigate the effects of topically applied 1% tropicamide, 2.5% phenylephrine and 1% cyclopentolate on retinal vessel calliper (VC) using optical coherence tomography (OCT). Methods: Patients who came to the ophthalmology clinic for routine examination and whose OCT films were taken before dilatation and after 30 min of last dilatation drop were included in the study. 90 ophthalmologically healthy subjects were divided into 3 groups of 30 subject each according to the application of the drops as follows: Tropicamide group (Group 1), Phenylephrine group (Group 2), Cyclopentolate group (Group 3). The right eyes of the subjects were dilated with drops and the left eyes were taken as the control group. VC of retinal artery and vein passing through an area one-half to one-disc diameter from the optic disc margin were measured from OCT films. The mean of the sum of superior retinal artery (SRA) and inferior retinal artery (IRA) VC and the mean of the sum of superior retinal vein (SRV) and inferior retinal vein (IRV) VC before and after the drop were compared. Results: There was no statistically significant change in the mean sum of SRA and IRA VC and the mean sum of SRV and IRV VC before and after dilatation drops in all three groups. Conclusion: Dilatation drops have no statistically significant effect on retinal artery and vein VC. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the impact of high-risk optic disc (HROD) on central retinal vein occlusion (CRVO) in patients with metabolic disorder(s). Design: Retrospective case-control study. Methods: A case-control study involving CRVO patients with metabolic disorder(s) was performed. PART I. All eligible patients with CRVO were included in CRVO group, and a similar number of patients with metabolic disorder(s) without CRVO were matched by sex, age and blood glucose level in the non-CRVO group. Various parameters were compared between groups. The impact of risk factors associated with CRVO was presented as odds ratios (ORs) and 95% confidence interval (95% CI). PART II. All eyes with CRVO that underwent intravitreal treatment (IVT) with a follow-up duration of ≥1 year were divided into non-HROD and HROD groups, and the differences between the two groups were compared. Results: In PART I, a total of 45 and 63 eyes were enrolled in the CRVO and non-CRVO groups, respectively, with a significant statistical difference in HROD (51.16% vs 26.98%, p = 0.010) between them. In further multivariate regression analysis, HROD was the independent risk factor for CRVO (OR = 5.036, 95% CI 1.847-13.729, p = 0.002). In PART II, demographic, follow-up information, treatment, and prognosis showed no significant statistical difference between the two groups (all p > 0.05).* Conclusion: HROD was likely to be an independent risk factor for CRVO occurrence in patients with metabolic disorder(s), but it did not affect the treatment and prognosis of CRVO eyes with HROD. [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]

Purpose: In this study, we aimed to evaluate and compare the effects of intravitreal aflibercept (IVA) and intravitreal faricimab (IVF) injections on the blood flow of retinal vessels in the peripapillary region and optic nerve head (ONH) in eyes with diabetic macular edema (DME) using laser speckle flowgraphy (LSFG). Patients and Methods: This study included 20 eyes of 18 patients treated with IVA and 15 eyes of 11 patients treated with IVF for DME. The mean blur rate (MBR) of the ONH and retinal artery and vein of the peripapillary region were measured using LSFG at baseline and 1 month after injection. Central retinal thickness (CRT) and best-corrected visual acuity (BCVA) were measured for all patients. Results: CRT decreased significantly in both IVA-treated (p = 0.0003) and IVF-treated groups (p = 0.0004). Some of the MBR-related parameters of the ONH, such as MBR of all areas (MA), MBR of vascular areas (MV), and MBR of tissue areas (MT), decreased significantly 1 month after IVA and IVF compared to baseline values (MA of IVA, p < 0.0001; MT of IVA, p = 0.0220; MA of IVF, p = 0.0002; MT of IVF, p = 0.0461). MBR of the retinal artery (MBR-A) and vein (MBR-V) also decreased significantly 1 month after IVA and IVF compared with baseline values (MBR-A of IVA, p = 0.0002; MBR-V of IVA, p = 0.0010; MBR-A of IVF, p = 0.0368). No significant difference in ocular perfusion was observed between the IVA-treated and IVF-treated groups. Conclusion: Intravitreal injection led to a reduction in ocular blood flow in both retinal peripapillary vessels and the ONH in both IVA-treated and IVF-treated groups. No significant difference was observed in MBR reduction between the IVA-treated and IVF-treated groups. Our findings warrant further long-term investigations to reveal differences between aflibercept and faricimab. [ABSTRACT FROM AUTHOR]

Background: Carotid artery stenosis (CAS) is one of the most common macrovascular complications of hypertension. The ophthalmic artery springs from the internal carotid artery; however, the effect of CAS on ocular microcirculation has not been quantified in hypertension patients. This study aimed to quantify ocular microcirculation metrics in hypertension with CAS (HCAS) patients and to explore the relationship between micro- and macroangiopathy in hypertension. Methods: All participants (community-based) underwent detailed assessments, including carotid ultrasonography, optical coherence tomography angiography (OCTA), and enhanced depth imaging (EDI)-OCT. CAS was diagnosed using carotid ultrasonography. Retinal microcirculation metrics, including vessel density (VD), skeleton density (SD), fractal dimension (FD), and foveal avascular zone (FAZ), were quantified using OCTA and ImageJ software. Choroidal microcirculation metrics, including subfoveal choroidal thickness (SFCT), luminal area (LA), and choroidal vascularity index (CVI), were quantified using EDI-OCT and ImageJ. Retinal vessel caliber metrics, including central retinal artery equivalent (CRAE), central retinal vein equivalent (CRVE), and artery/vein ratio (AVR), were calculated using revised formulas. The above metrics were compared among the HCAS group, hypertension with no CAS (HNCAS) group, and healthy control group. The mutual effects between ocular metrics and CAS were evaluated using regression analyses. Results: In a comparison of the HCAS vs. HNCAS groups, retinal metrics including VD, SD, FD, and choroidal metrics including CVI and LA were significantly decreased in the HCAS group (all p < 0.05); however, FAZ, SFCT, and retinal vessel caliber metrics including CRAE, CRVE, and AVR were comparable between groups (all p > 0.05). In a comparison of HNCAS and the healthy control group, VD, SD, and CRAE showed that AVR was significantly decreased in the HNCAS group (all p < 0.05); meanwhile, choroidal metrics were comparable between groups (all p > 0.05). Linear regression analyses showed that intimamedia thickness (IMT) (p = 0.01) and peak systolic velocity (PSV) (p = 0.002) were negatively related to retinal VD in hypertension patients. Logistic regression analyses disclosed that older age (p < 0.001), smoking history (p = 0.002), lower VD (p = 0.04), SD (p = 0.02), and CVI (p < 0.001) were related to the presence of CAS in hypertension patients. Conclusion: CAS in hypertension-induced hypoperfusion in retinal and choroidal microcirculation and the decreased retinal VD and choroidal CVI were significantly associated with the presence of CAS in patients with hypertension, suggesting that hypertension macro- and microangiopathy were mutually affected and share the common pathophysiology. Furthermore, OCT could be a useful tool to assess hypertension patient's CAS risk profiles in a non-invasive way. [ABSTRACT FROM AUTHOR]

Retinal vein cannulation involves puncturing an occluded vessel on the micron scale. Even single millinewton force can cause permanent damage. An ophthalmic robot with a piezo-driven injector is precise enough to perform this delicate procedure, but the uncertain viscoelastic characteristics of the vessel make it difficult to achieve the desired contact force without harming the retina. The paper utilizes a viscoelastic contact model to explain the mechanical characteristics of retinal blood vessels to address this issue. The uncertainty in the viscoelastic properties is considered an internal disturbance of the contact model, and an active disturbance rejection controller is then proposed to precisely control the contact force. The experimental results show that this method can precisely adjust the contact force at the millinewton level even when the viscoelastic parameters vary significantly (up to 403.8%). The root mean square (RMS) and maximum value of steady-state error are 0.32 mN and 0.41 mN. The response time is below 2.51 s with no obvious overshoot. [ABSTRACT FROM AUTHOR]

Copyright of MN Opthalmology / MN Oftalmoloji is the property of Medical Network 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.)

Central serous chorioretinopathy (CSC) is a leading cause of permanent vision loss, ranking fourth among macular diseases, trailing only age-related macular degeneration, diabetic retinopathy, and retinal vein obstruction. While mounting evidence implicates inflammation as a pivotal factor in the onset and advancement of CSC, the specific pathophysiological process and molecular mechanisms underlying inflammation remain incompletely understood. A complex network of cytokines, chemokines, and adhesion molecules interplay to trigger inflammatory and pathological cascades, highlighting the need for a comprehensive comprehension of the inflammation-related mechanisms behind CSC progression. In this piece, we examine the existing comprehension of CSC’s pathology and pathogenesis. Additionally, we present an overview of the mechanisms underlying the onset and progression of CSC inflammation, followed by a thorough analysis and discussion of the potential of targeted inflammatory intervention for both preventing and treating CSC. [ABSTRACT FROM AUTHOR]

Kounis Syndrome (KS) is a clinical entity triggered by allergic or hypersensitivity reactions capable of inducing acute coronary events. Several causes can induce KS, including drugs and insect stings. Here, a rare case of post mortem assessment of fatal KS related to fluorescein retinal angiography has been reported. An 80-year-old man in follow-up for a retinal vein thrombosis underwent a retinal fluoroangiography. Approximately 30 min later, the patient complained of sweating and dizziness, and suddenly lost consciousness due to a cardiac arrest. Despite the immediate cardiopulmonary resuscitation, he died. The autopsy revealed foamy yellowish edema in the respiratory tract and coronary atherosclerosis with eccentric plaques partially obstructing the lumen. The routine histology highlighted lung emphysema and myocyte break-up with foci of contraction band necrosis at the myocardial tissue. Biochemistry showed increased serum tryptase, troponin, and p-BNP. Activated and degranulated (tryptase) mast cells were detected, using immunohistochemistry, in the larynx, lungs, spleen, and heart. Acute myocardial ischemia due to allergic coronary vasospasm related to fluorescein hypersensitivity has been assessed as cause of death. KS-related deaths are considered rare events, and the post mortem assessment of KS quite difficult. The integration of several investigations (gross and microscopic examination, biochemistry, immunohistochemistry) can provide useful findings to support the diagnosis, helping to reduce the unrecognized cases as much as possible. [ABSTRACT FROM AUTHOR]

To develop a highly efficient and fully automated method that measures retinal vessel caliber using digital retinal photographs and evaluate the association between retinal vessel caliber and hypertension. The subjects of this study were from two sources in Beijing, China, a hypertension case-control study from Tongren Hospital (Tongren study) and a community-based atherosclerosis cohort from Peking University First Hospital (Shougang study). Retinal vessel segmentation and arteriovenous classification were achieved simultaneously by a customized deep learning model. Two experienced ophthalmologists evaluated whether retinal vessels were correctly segmented and classified. The ratio of incorrectly segmented and classified retinal vessels was used to measure the accuracy of the model's recognition. Central retinal artery equivalents, central retinal vein equivalents and arteriolar-to-venular diameter ratio were computed to analyze the association between retinal vessel caliber and the risk of hypertension. The association was then compared to that derived from the widely used semi-automated software (Integrative Vessel Analysis). The deep learning model achieved an arterial recognition error rate of 1.26%, a vein recognition error rate of 0.79%, and a total error rate of 1.03%. Central retinal artery equivalents and arteriolar-to-venular diameter ratio measured by both Integrative Vessel Analysis and deep learning methods were inversely associated with the odds of hypertension in both Tongren and Shougang studies. The comparisons of areas under the receiver operating characteristic curves from the proposed deep learning method and Integrative Vessel Analysis were all not significantly different (p >.05). The proposed deep learning method showed a comparable diagnostic value to Integrative Vessel Analysis software. Compared with semi-automatic software, our deep learning model has significant advantage in efficiency and can be applied to population screening and risk evaluation. [ABSTRACT FROM AUTHOR]

Purposes: Retinal vein occlusion (RVO) is a major cause of vision loss. Its pathogenesis is still not completely understood. Our aim was to describe patients with RVO, to precise risk factors responsible to retinal vasculopathy in our population and to assess the prevalence of thrombophilia disorders patients with RVO, compared to population-based group of age- and sex-matched controls. Patients & methods: Our study was retrospective conducted from 1 January 2013, until 30 June 2019, including 57 patients with RVO compared to 105 controls patient's age- and sex-matched free of any visual disorders. Among 57 RVO cases, 26 were men and 31 were women. Results: The mean age was 45.0±14.7 years. Among systemic and ocular risk factors for RVO we found hypertension in 12 patients (31.6%), dyslipidemia in four patients (10.5%), diabetes in four patients (10.5%), and smoking in six patients (16.2%). Three patients (9.7%) had glaucoma and two patients (6.5%) had diabetic retinopathy. Ophthalmology examination found unilateral RVO in 52 patients (91.0%) and bilateral RVO in five patients (11.1%). Retinal angiography showed ischemic signs in seven patients (18.4%). Non-ischemic RVO was retained in 31 cases (81.6%). Macular edema was present in 12 patients (38.7%). Six cases (19.4%) developed neovascular glaucoma and two cases (6.5%) presented reversible blindness. Measures of thrombophilia practiced in 57 patients revealed 13 abnormalities (22.8%): Isolated thrombophilia disorder in 11 patients (71.4%) and combined prothrombotic disorder in two others. Conclusions: Among systemic and ocular risk factors for RVO, we found hypertension in 12 patients (31.6%). Thrombophilia disorders were also common. [ABSTRACT FROM AUTHOR]

Insufficient blood flow within the retinal vessels is believed to be the root cause of several optical problems, including partial vision loss and blindness. The appearance and growth of veins in retinal images are crucial for identifying ocular contamination. It is therefore a significant task for the research community to explore and segment these retinal blood vessels. For a wide range of purposes, including biometric authentication, computer-assisted laser surgery, automated screening, and the detection of ophthalmic pathologies like diabetic retinopathy (DR), age-related macular degeneration, and hypertensive retinopathy, among others, accurate blood vessel delineation in retinal images is used. Stroke and cardiovascular disease are severe illnesses that are preceded by changes in the properties of retinal blood vessels. There are many alternatives to identifying an infection a person has through their eyes in the broad development of innovation, such as diabetes, hypertension, heart disease, rheumatoid arthritis, etc. Examining retinal vascular features can therefore help to spot these changes and allow a person to respond quickly while the illness is still in its early stages. The use of computer-based automation in this procedure would reduce the costs associated with hiring qualified graders and solve the issue of inconsistency that results from manual grading. Numerous tasks involving retinal analysis require the segmentation of retinal vessels because it facilitates the execution of subsequent measures. As a result, segmentation is crucial to the study of retinal images. In the current study, a successful method for automatically extracting blood vessels from coloured retinal pictures is described. In order to solve the retinal blood vessel segmentation problem, we applied feature extraction methodologies and machine learning (ML) techniques in this research. This method uses pixel-based feature extraction, where each pixel has its own feature vector. Five distinct feature groups are employed for feature extraction: the basic line detector for line strength, the orthogonal line detector, the frangi filter, the average grey level features, and the gabor filter. The four machine learning classifiers—K-Nearest Neighbour (KNN), Support Vector Machine (SVM), Naive Bayes, and Decision Tree—are trained using the training data. A DRIVE dataset is used to test the system; it is a benchmark, standard, widely accepted, and openly accessible to the general public. Blood vessel segmentation from fundus pictures is measured using performance metrics like precision, sensitivity, specificity, area under the curve (AUC), and accuracy as success indicators. With the given method, the maximum accuracy achieved is 0.9623 using KNN, 0.9463 using SVM, 0.9459 using Naive Bayes, and 0.9624 using Decision Tree. The findings of previously published extremely efficient approaches are comparable to the performance of the suggested strategy, which has demonstrated great performance. The recommended method can be used as an alternate automated tool for segmenting retinal blood vessels. [ABSTRACT FROM AUTHOR]

Purpose: To compare the results of retinal venous pressure (RVP) measurement performed with contact lens dynamometry (CLD) and with the new IOPstim. Methods: In this cross-sectional study, we included 36 patients with primary open angle glaucoma with a median age (Q25; Q75) of 74 (64; 77) years (m/f = 18/18), baseline intraocular pressure (IOP): 13.9 (12.2; 15.1) mmHg. Median mean defect: − 5.8 (− 11.9; − 2.6) db. Principle of the IOPstim: an empty balloon with a diameter of 8 mm is positioned on the eye, laterally of the limbus. Under observation of the central retinal vein (CRV), the examiner inflates the balloon. As soon as the CRV starts pulsation, the inflation is stopped and the IOP is measured, equaling the RVP at this moment. In the CLD, the pulsation of the CRV is observed with a contact lens. The RVP is calculated from the attachment force applied when pulsation appears. Course of examinations: Three single measurements of RVP in quick succession with both methods. The sequence of the two methods was randomized. The means of the three RVP measurements were compared. Results: Pressures in mmHg. RVP: IOPstim: 19.4 ± 5.4 (mean ± SD), CLD: 20.3 ± 5.9. Range of three single measurements: IOPstim: 2.9 ± 1.5, CLD: 2.2 ± 1.1. The differences were RVPIOPstim − RVPCLD = − 0.94 ± 1.15, and approximately normally distributed. Bland–Altman analysis: only one data point was 0.5 mmHg higher than the upper line of agreement. The confidence interval of this line was 0.65 mmHg. Concordance correlation coefficient according to Lin (CCC): 0.96. Intraclass correlation coefficient: both methods, 0.94. Conclusion: In both methods, the range of the single measurements may be taken as a sign of good reliability, the CCC of 0.96 as a sign of a very good agreement. At the mean, the IOPstim RVP values were 1 mmHg lower than those obtained with the CLD. This difference may be due to the different directions of the prevailing force vectors induced by the instruments. The IOPstim seems applicable in glaucoma diagnostics. [ABSTRACT FROM AUTHOR]

Since coronavirus disease infection-19 (COVID-19) entry to the cells is angiotensin enzyme receptor (ACEII) dependent, extrapulmonary manifestations have been suspected. Ocular manifestations reported in several studies to involve the anterior as well as posterior eye segments. However, the predominance of the anterior eye segment reduced the attention of the scientific community on the posterior eye segment. Our results showed that the incidence of changes in the posterior eye segment is 1/5 of the anterior eye segment. Posterior eye segment manifestations include acute macular neuroretinopathy and paracentral middle maculopathy, central retinal vein/artery occlusion, reactivation of previous uveitis, varicella zoster virus-related acute retinal necrosis in an immunocompromised patient, chorioretinitis, macular hemorrhage, paracentral acute middle maculopathy, retinal detachment, and vitritis with outer retinal abnormalities. The pathogenesis of posterior eye segment manifestations under COVID-19 includes viremia, autoimmune vasculitis, hyperimmune response, coagulopathy, and cytokine storm. A full ophthalmological examination is crucial for patients recovering from COVID-19. The paper provided up-to-date manifestations with potential underlying pathophysiological mechanisms of development, as well as pathogenetic therapy. [ABSTRACT FROM AUTHOR]

Introduction: The classically defined two retinal microglia layers are distributed in inner and outer plexiform layers. Although there are some reports that retinal microglia are also superficially located around the ganglion cell layer (GCL) in contact with the vitreous, there has been a lack of detailed descriptions and not fully understood yet. Methods: We visualized the microglial layers by using CX3CR1-GFP (C57BL6) transgenic mice with both healthy and disease conditions including NaIO3- induced retinal degeneration models and IRBP-induced auto-immune uveitis models. Result: We found the GCL microglia has two subsets; peripheral (pph) microglia located on the retinal parenchyma and BAM (CNS Border Associated Macrophage) which have a special stretched phenotype only located on the surface of large retinal veins. First, in the pph microglia subset, but not in BAM, Galectin-3 and LYVE1 are focally expressed. However, LYVE1 is specifically expressed in the amoeboid or transition forms, except the typical dendritic morphology in the pph microglia. Second, BAM is tightly attached to the surface of the retinal veins and has similar morphology patterns in both the healthy and disease conditions. CD86+ BAM has a longer process which vertically passes the proximal retinal veins. Our data helps decipher the basic anatomy and pathophysiology of the retinal microglia in the GCL. Discussion: Our data helps decipher the basic anatomy and pathophysiology of the retinal microglia in the GCL. [ABSTRACT FROM AUTHOR]

Microinjection is usually applied to the treatment of some retinal disorders, such as retinal vein cannulation and displaced submacular hemorrhage. Currently, the microinjection procedure is usually performed by using the viscous fluid control of a standard vitrectomy system, which applies a fixed air pressure through foot pedal activation. The injection process with the fixed pressure is uncontrollable and lacks feedback, the high flow rate of the injected drug may cause damage to the fundus tissue. In this paper, a liquid-driven microinjection system with a flow sensor is designed and developed specifically for fundus injection. In addition, a PID sliding mode control (SMC) method is proposed to achieve precise injection in the injection system. The experimental results of fundus simulation injection demonstrate that the microinjection system meets the requirements of fundus injection and reduces the impact of the injection process on the fundus tissue. [ABSTRACT FROM AUTHOR]

The given text is a list of references related to Terson's Syndrome, a condition characterized by bleeding in the eye that occurs as a result of subarachnoid hemorrhage. The references include studies, case reports, and reviews that discuss various aspects of Terson's Syndrome, such as its incidence, clinical features, diagnostic methods, and treatment options. The references provide valuable information for researchers and healthcare professionals interested in understanding and managing this condition. [Extracted from the article]

Aim of the study: To study the peculiarities of retinal changes’ structure and frequency according to fundoscopy data in patients with different clinical course of COVID-19. Material and methods: This was prospective, uncontrolled crosssectional study. A total of 117 patients (234 eyes) with varying severity of COVID-19 clinical course were divided into groups: 1) an extremely severe course; 2) a severe course; 3) moderate severity with decompensated accompanying pathology; 4) moderate severity with compensated concomitant pathology. Registration of patients’ eye fundus with the portable fundus camera Pictor Plus Fundus Camera and VistaView (Volk Optical). Results: Cotton wool spots, narrowed retinal vessels, central retinal vein occlusion (CRVO) (8.8%), petechial and intraretinal hemorrhages (23.5%), tortuosity and dilatation of retinal venules (11.8%), prethrombosis of the central retinal vein (CRV) (a state determined by venous blood stasis, characterized by dilated appearance of the eye fundus veins, their dark color, curved structure, optic nerve edema) (2.9%) and vitreous hemorrhage (5.9%) were found in 1st group patients; in 29.4% of cases there were no retinal changes. Retinal changes were absent in 59.3% in 4th group patients and in 86.7% in 3rd group patients; no clinically significant retinal changes were detected in these patients. Conclusions: Retinal changes’ structure and frequency in patients with COVID-19 correlate with the severity of its clinical course. Within 1st group patients cotton wool spots, narrowed retinal vessels, petechial and intraretinal hemorrhages, thrombosis/prethrombosis of CRV, tortuosity and dilatation of retinal venules, and vitreous hemorrhage are diagnosed, which is significantly more common than in patients of 3rd and 4th groups (p < 0.05). A trend of decreasing risk of clinically significant retinal changes (thrombosis/ prethrombosis of CRV) and vitreous hemorrhage with decreasing severity of the disease was observed. [ABSTRACT FROM AUTHOR]

"Advancing the Frontiers of Retinal Vasculitis: Insights, Challenges, and Future Directions" published in Ophthalmologica explores the complexities of retinal vasculitis (RV), an inflammatory condition that can lead to severe vision loss if not promptly diagnosed and treated. The article highlights the diverse etiologies of RV, ranging from systemic inflammatory diseases to infectious agents, and the challenges in diagnosis and management. It emphasizes the importance of multimodal imaging, biologic therapies, and standardized diagnostic criteria to improve patient outcomes. The need for harmonized treatment approaches, imaging protocols, and a universally accepted classification system for RV is also underscored to advance research and enhance patient care. [Extracted from the article]

We conducted a scoping review of studies examining ambient air pollution as a risk factor for chronic eye disease influencing the lens, retina, and intraocular pressure in adults. Terms related to air pollution and eye disease outcomes were used to search for publications on Embase, Web of Science Core Collection, Global Health, PubMed, and the Cochrane Central Register of Controlled Trials from January 1, 2010, through April 11, 2022. We identified 27 articles, focusing on the following non-mutually exclusive outcomes: cataract (n = 9), presbyopia (n = 1), retinal vein occlusion or central retinal arteriolar and venular equivalents (n = 5), intraocular pressure (IOP) (n = 3), glaucoma (n = 5), age-related macular degeneration (AMD) (n = 5), diabetic retinopathy (n = 2), and measures of retinal morphology (n = 3). Study designs included cross-sectional (n = 16), case–control (n = 4), and longitudinal (n = 7). Air pollutants were measured in 50% and 95% of the studies on lens and retina or IOP, respectively, and these exposures were assigned to geographic locations. Most research was conducted in global regions with high exposure to air pollution. Consistent associations suggested a possibly increased risk of cataract and retina-associated chronic eye disease with increasing exposure to particulate matter (PM2.5-PM10), NO2, NOx, and SO2. Associations with O3 were less consistent. Accumulating research suggests air pollution may be a modifiable risk factor for chronic eye diseases of the lens and retina. The number of studies on each specific lens- or retina-related outcome is limited. Guidelines regarding the role of air pollution in chronic eye disease do not exist. [ABSTRACT FROM AUTHOR]

Background: To review cases of branch retinal vein occlusion (BRVO) secondary to rhegmatogenous retinal detachment (RRD) and its surgical management and presume their mechanism. Methods: Medical records of patients who underwent surgery for RRD between 2015 and 2019 at a single tertiary care center were retrospectively reviewed. New BRVO secondary to RRD or its surgical procedure was diagnosed based on the fundus examination and its clinical course. Results: A total of 734 RRD surgeries were performed for five years, and six cases of new BRVOs were noticed in the first year after surgery (incidence was 0.68%: six cases of BRVO / 734 cases of surgical RRD); five cases occurred after vitrectomy, and one occurred after scleral buckling. In three cases, retinal veins were presumed to already be partially occluded related due to a kink of the retinal vein seen before surgery. In the other three cases, the retinal veins were presumed to have incurred damage during vitrectomy. Conclusion: In the present cohort, RRD or its related procedures caused BRVO within a year of surgery at an incidence of 0.68%. The proposed mechanisms are kinks of the retinal vein on the detached retina and damage to the retinal vein during vitrectomy. [ABSTRACT FROM AUTHOR]

Background: High cholesterol impacts blood vesssels in every part of the body. Lipemia retinalis is a rare retinal presentation of severe hypertriglyceridemia (usually greater than 2000 mg/dl), resulting in a creamy-white discoloration of retinal blood vessels. The following case presents a pediatric case of lipemia retinalis. Case Report: A 15-year-old Hispanic female presented for an annual diabetic eye exam. She reported that her vision had been blurry OU since she lost her glasses. Her medical history included type 2 DM, diagnosed 1 year prior. Her last blood glucose was 208 mg/dL, and she did not know her HbA1c. Her medications included metformin and insulin. DFE revealed creamy-white colored arteries and veins in both eyes and a salmon-colored fundus, but no evidence of diabetic retinopathy. OCT showed increased signal in the blood vessel lumens. Her lab work showed total cholesterol of 1328 mg/dL and triglycerides of 7337 mg/ dL. The PCP started the patient on a low-fat diet, antitryglyceride, and anticholesteral medication. Conclusion: Visual sequelae associated with lipemia retinalis is rare, as most patients are visually asymptomatic. There is no treatment for the lipemia retinalis itself, other than managing the underlying systemic metabolic pathologies. Coordination with the primary care physician is required. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to assess the effect of bariatric surgery on retinal microvascular calibre, peripheral microvascular function, peripheral pressure waveforms, and the general cardiovascular disease (CVD) risk in obese individuals after undergoing Roux-en-Y gastric bypass (RYGB) surgery. Methods: A total of 29 obese participants were included in the study. All of the measurements were conducted at two time points: before and one year following the bariatric surgery procedure. General anthropometric data, as well as blood markers for glucose, cholesterol, and triglycerides were assessed in all individuals. In all participants, the Framingham risk score (FRS), and retinal vessel calibre measurements, using a Zeiss fundus camera and VesselMap software (ImedosSystems, Jena, Germany), were performed. Systemic arterial stiffness was measured by pulse wave analysis (PWA), and peripheral microvascular reactivity by way of digital thermal monitoring (DTM) in all participants. Results: As expected, various general anthropometric parameters, including body mass index (BMI), waist circumference and neck circumference, were significantly decreased post-surgery comparing to baseline in all individuals (all p < 0.001). In addition, their general CVD risk, as measured using FRS, was significantly improved (p < 0.001). At the retinal vascular level, central retinal artery equivalent (CRAE) as well as, central retinal vein equivalent (CRVE) had increased after surgery comparing to the baseline values (p = 0.003 and p = 0.007, respectively). In addition, both systemic arterial stiffness and peripheral microvascular reactivity had improved in all participants (p < 0.001 and p = 0.008 respectively). Conclusions: Our findings suggest that bariatric surgery has a positive effect on the overall vascular health, as well as on the general CVD risk of the obese patients undergoing this procedure. [ABSTRACT FROM AUTHOR]