Search Results (132)

Background: Rowing is a highly demanding endurance sport, requiring simultaneous work of approximately 70% of the body’s muscle mass and the combined contribution of aerobic and anaerobic energy systems. Objective: This study aimed to analyze the cardiorespiratory responses and performance characteristics of elite junior male and female rowers during maximal effort over 2000 m on a rowing ergometer. Methods: Fifteen junior rowers (six males aged 15–17 and nine females aged 15–18) participated in the study. Anthropometric data (body height, weight, and body surface area) were recorded. All participants performed a maximal 2000 m test on a Concept2 D-model ergometer. Throughout the test, oxygen uptake (VO₂), carbon dioxide production (VCO₂), heart rate, and ventilation parameters were continuously measured. Performance and physiological data were analyzed in three intensity zones, defined by ventilatory thresholds (VT1–VT3), as well as at peak exercise. Results: Significant anthropometric differences were observed between genders. In terms of performance, males completed the 2000 m test significantly faster than females (208.83 ± 87.66 s vs. 333.78 ± 97.51 s, p = 0.0253). Relative VO₂ at peak exercise was higher in males (58.73 ± 5.25 mL·kg⁻¹·min⁻¹) than females (48.32 ± 6.09 mL·kg⁻¹·min⁻¹, p = 0.0046). In most cardiorespiratory parameters, males outperformed females significantly, except for heart rate and ventilatory equivalents. Ranking analysis revealed that higher VO₂max values were generally associated with a better placement in both genders, though this relationship was not perfectly linear. Performance time was negatively correlated with VO₂Peak (r = −0.8286; p < 0.001), rVO₂Peak (r = −0.6781; p < 0.01), and O₂P_Peak (r = −0.7729; p < 0.01). Conclusions: The findings confirm significant gender differences in anthropometric and cardiorespiratory characteristics of elite junior rowers and reinforce VO₂max as a key determinant of performance. Yet, deviations from a direct VO₂max–rank correlation highlight the influence of tactical, psychological, and biomechanical factors. Future research should provide practical recommendations for monitoring performance and tailoring training to optimize adaptation and long-term athlete development. Full article

Obstructive sleep apnea (OSA) is a common condition associated with intermittent hypoxia, systemic inflammation, and vascular dysfunction; mechanisms implicated in retinal disease pathogenesis. This real-world retrospective cohort study used data from the TriNetX Research Network to assess whether continuous positive airway pressure (CPAP) therapy reduces retinal disease incidence among adults with OSA and BMI between 25.0 and 30.0 kg/m². After 1:1 propensity score matching, 101,754 patients were included in the analysis. Retinal outcomes included diabetic retinopathy (DR), age-related macular degeneration (AMD), retinal vein occlusion (RVO), and central serous chorioretinopathy (CSC). CPAP use was associated with a modest but statistically significant reduction in DR (3.2% vs. 3.4%, RR: 0.922, p = 0.016) and AMD (2.1% vs. 2.3%, RR: 0.906, p = 0.018), while no significant differences were found for RVO or CSC. These findings support prior evidence linking CPAP to improved retinal microvascular health and suggest a protective effect against specific retinal complications. Limitations include a lack of data on CPAP adherence, OSA severity, and imaging confirmation. Still, this study highlights the importance of interdisciplinary care between sleep and eye health, and the need for further prospective studies to validate CPAP’s role in preventing retinal disease progression in OSA patients. Full article

Background: Retinal diseases are becoming an important public health issue, with early diagnosis and timely intervention playing a key role in preventing vision loss. Optical coherence tomography (OCT) remains the leading non-invasive imaging technique for identifying retinal conditions. However, distinguishing between diabetic macular edema (DME) and macular edema resulting from retinal vein occlusion (RVO) can be particularly challenging, especially for clinicians without specialized training in retinal disorders, as both conditions manifest through increased retinal thickness. Due to the limited research exploring the application of deep learning methods, particularly for RVO detection using OCT scans, this study proposes a novel diagnostic approach based on stacked convolutional neural networks. This architecture aims to enhance classification accuracy by integrating multiple neural network layers, enabling more robust feature extraction and improved differentiation between retinal pathologies. Methods: The VGG-16, VGG-19, and ResNet50 models were fine-tuned using the Kermany dataset to classify the OCT images and afterwards were trained using a private OCT dataset. Four stacked models were then developed using these models: a model using the VGG-16 and VGG-19 networks, a model using the VGG-16 and ResNet50 networks, a model using the VGG-19 and ResNet50 models, and finally a model using all three networks. The performance metrics of the model includes accuracy, precision, recall, $F_2$-score, and area under of the receiver operating characteristic curve (AUROC). Results: The stacked neural network using all three models achieved the best results, having an accuracy of 90.7%, precision of 99.2%, a recall of 90.7%, and an $F_2$-score of 92.3%. Conclusions: This study presents a novel method for distinguishing retinal disease by using stacked neural networks. This research aims to provide a reliable tool for ophthalmologists to improve diagnosis accuracy and speed. Full article

Background: Retinal vascular occlusion (RVO) and retinal artery occlusion (RAO) have been reported as rare adverse events following COVID-19 vaccination, raising concerns about vaccine safety. This review synthesizes cohort and case–control studies assessing the association between COVID-19 vaccines and RVO/RAO, while exploring potential pathophysiological mechanisms. Methods: We analyzed large-scale population-based studies from South Korea, Europe, and the TriNetX database, focusing on odds ratios (OR), hazard ratios (HR), and relative risks (RR) across mRNA and adenoviral vector vaccines. Pathological processes were hypothesized based on molecular and clinical evidence. Results: Studies investigating the association between COVID-19 vaccination and retinal vascular occlusion show conflicting results; some studies report no association (e.g., OR 0.93, 95% CI 0.60–1.45), others suggest reduced risk (e.g., OR 0.80, 95% CI 0.64–0.99), and one indicates increased risk over two years (HR 2.19, 95% CI 2.00–2.39). Adenoviral vector vaccines, particularly ChAdOx1, show higher RAO incidence in specific cohorts. Proposed mechanisms include vaccine-induced immune thrombotic thrombocytopenia (VITT) via anti-PF4 antibodies, spike protein-mediated endothelial dysfunction, and adjuvant-driven inflammation. Conclusions: While causality remains unproven, temporal heterogeneity and vaccine type-specific risks warrant further investigation. Longitudinal studies with robust controls are needed to clarify these associations in the post-pandemic context. Full article

For tropical forests characterized by tall and densely packed trees, even long-wavelength SAR signals may fail to achieve full penetration, posing a significant challenge for retrieving sub-canopy terrain using polarimetric interferometric SAR (InSAR)(PolInSAR) techniques. This paper proposes a single-baseline PolInSAR-based correction method for sub-canopy terrain estimation based on a one-dimensional lookup table (LUT) that links forest height to unpenetrated depth. The approach begins by applying an optimal normal matrix approximation to constrain the complex coherence measurements. Subsequently, the difference between the PolInSAR Digital Terrain Model (DTM) derived from the Random Volume over Ground (RVoG) model and the LiDAR DTM is defined as the unpenetrated depth. A nonlinear iterative optimization algorithm is then employed to estimate forest height, from which a fundamental mapping between forest height and unpenetrated depth is established. This mapping can be used to correct the bias in sub-canopy terrain estimation based on the PolInSAR RVoG model, even with only a small amount of sparse LiDAR DTM data. To validate the effectiveness of the method, experiments were conducted using fully polarimetric P-band airborne SAR data acquired by the European Space Agency (ESA) during the AfriSAR campaign over the Mabounie region in Gabon, Africa, in 2016. The experimental results demonstrate that the proposed method effectively mitigates terrain estimation errors caused by insufficient signal penetration or the limitation of single-interferometric geometry. Further analysis reveals that the availability of sufficient and precise forest height data significantly improves sub-canopy terrain accuracy. Compared with LiDAR-derived DTM, the proposed method achieves an average root mean square error (RMSE) of 5.90 m, representing an accuracy improvement of approximately 38.3% over traditional RVoG-derived InSAR DTM retrieval. These findings further confirm that there exist unpenetrated phenomena in single-baseline low-frequency PolInSAR-derived DTMs of tropical forested areas. Nevertheless, when sparse LiDAR topographic data is available, the integration of fully PolInSAR data with LUT-based compensation enables improved sub-canopy terrain retrieval. This provides a promising technical pathway with single-baseline configuration for spaceborne missions, such as ESA’s BIOMASS mission, to estimate sub-canopy terrain in tropical-rainforest regions. Full article

Background/Objectives: Retinal vein occlusion (RVO) represents a common ophthalmological disorder that, if untreated, often leads to severely impaired vision. The classic vascular risk factors, aging and glaucoma, represent the core pathogenic factors for RVO. However, antiphospholipid syndrome (APS) has been involved in a non-negligible number of patients with RVO. The main objective of the present study was to assess the performance of the new 2023 ACR/EULAR classification criteria for APS in a cohort of patients with RVO fulfilling the Sydney classification criteria. Methods: A prospective study of consecutive patients with RVO diagnosed with APS in a third-level university hospital. The new 2023 ACR/EULAR classification criteria for APS were applied to all patients. Vascular risk factors, the antiphospholipid antibody (aPL) profile, clinical management, and clinical outcomes were assessed and compared between those fulfilling the Sydney and the 2023 ACR/EULAR criteria. Results: Sixty-nine RVO-APS patients were included in the study. After applying the new classification criteria, 18 patients (26.1%) did not fulfill the new criteria for APS. Specifically, 17 (24.6%) were excluded due to the new Domain 8 (p < 0.001) as they presented only aPL IgM serology, and 1 patient (1.4%) was excluded due to having high venous thromboembolic risk (VTE) with a clinical domain score < 3. Interestingly enough, the presence of high arterial risk (45.1% vs. 50%; p = 0.72) was greater than the presence of high VTE (3.9% vs. 5.6%; p = 0.99); in both cases, the 51 RVO-APS patients were classified with the 2023 ACR/EULAR criteria, and the 18 cases were excluded according to the new classification criteria. Except for the expected differences in serological domains (Domain 7, p < 0.001, and Domain 8, p < 0.001), we did not find other significant differences in terms of prognosis or risk of recurrence between both groups of patients. Conclusions: The implementation of the new ACR/EULAR 2023 classification criteria for APS resulted in the exclusion of about one out of four previously diagnosed RVO-APS patients. The higher prevalence of manifestations of high arterial risk compared with high VTE among both newly classified and excluded APS patients highlights the importance of monitoring cardiovascular risk factors for both the prevention and the management of potential retinal and cardiovascular events. Full article

Background/Objectives: Retinal vein occlusion (RVO) is a major cause of vision loss globally. Although magnesium (Mg) is crucial for vascular health, its association with RVO risk is unknown. Thus, we aimed to further examine this association. Methods: This cross-sectional study included participants of the Korean National Health and Nutrition Examination Survey 2017–2021 aged ≥19 years (n = 16,358). RVO diagnosis was based on fundus imaging or was self-reported. Based on their daily Mg intake, we categorized participants into low (<120 mg), intermediate (men: 120–300 mg; women: 120–400 mg), and sufficient (men: ≥300 mg; women: ≥400 mg) intake groups and compared their characteristics across groups. Results: RVO prevalence was 0.7%. Compared to the non-RVO group, the RVO group was characterized by older individuals, fewer current alcohol consumers, a higher prevalence of hypertension and chronic kidney disease, and a lower intake of fiber, iron, calcium, vitamin E, and Mg. After full adjustment, sufficient Mg intake was significantly associated with a 64% reduced risk of RVO (odds ratio [OR] 0.36, 95% confidence interval [CI] 0.18–0.71, p = 0.003). This association was particularly notable among individuals aged 19–59 years (OR 0.18, 95% CI 0.04–0.82, p = 0.027), those with hypertension (OR 0.29, 95% CI 0.13–0.67, p = 0.003), and those without glaucoma (OR 0.33, 95% CI 0.15–0.71, p = 0.004). Conclusions: Sufficient Mg intake may reduce RVO risk among adults aged <60 years, individuals with hypertension, and those without glaucoma. Further research should validate the benefits of Mg supplementation in preventing RVO. Full article

Background/Objectives: Macular edema (ME), due to retinal vein occlusion (RVO), is a major cause of vision impairment. Many patients experience suboptimal responses to anti-vascular endothelial growth factor (anti-VEGF) monotherapy, necessitating alternative treatment approaches. Faricimab, a bispecific antibody targeting VEGF-A and angiopoietin-2 (Ang-2), introduces a novel dual-mechanism therapy. This study evaluates the short-term real-world efficacy of switching to Faricimab in patients with treatment-resistant ME secondary to RVO. Methods: This retrospective study included patients from LMU University Hospital who were switched to Faricimab due to an inadequate response or adverse events related to prior intravitreal therapy (Ranibizumab, Aflibercept, or Ozurdex^TM). All patients completed a structured loading phase of four monthly injections. Key outcome measures included changes in best-corrected visual acuity (BCVA, logMAR), central subfield thickness (CST, µm), and intraretinal fluid (IRF) presence on optical coherence tomography (OCT). Changes were assessed from baseline (mo0) to three months (mo3). Results: The study included 19 eyes from 19 patients (mean age 63.0 ± 14.2 years). BCVA improved from 0.20 logMAR at baseline to 0.00 logMAR at mo3 (p < 0.01). CST decreased from 325 µm to 280 µm (p < 0.01). The proportion of eyes with IRF reduced from 100% to 32% (p < 0.01). Significant reductions in retinal volume within the 1 mm and 6 mm (both p < 0.01) circles of the ETDRS grid were observed. Conclusions: Switching to Faricimab in patients resulted in significant short-term improvements in BCVA, CST, and IRF resolution. Given the small sample size and retrospective design, these findings should be interpreted as exploratory and hypothesis-generating. Further studies are needed to evaluate long-term efficacy and optimal treatment regimens. Full article

Purpose: To assess the feasibility and effectiveness of remote monitoring for patients with retinal vein occlusion (RVO) treated with intravitreal anti-VEGF injections. Methods: A retrospective analysis was conducted at the Eye Clinic of the University of Catania. Thirty-four eyes of 34 patients with RVO were included for a 12-month follow-up period. After a comprehensive baseline ophthalmic examination, the patients received a loading treatment consisting of three monthly intravitreal injections of anti-VEGF, followed by monthly or bimonthly remote follow-up visits at peripheral centers. Optical coherence tomography (OCT) images and clinical data were shared online with our eye clinic for remote evaluations. Data on hospital and peripheral center visits, intravitreal injections, and OCT scans were collected and analyzed. Results: The patients had an average of 5.71 ± 1.14 visits to peripheral centers and 2.1 ± 0.8 visits to our center for fluorescein angiography. The mean number of injections was 5.26 ± 1.29 and the mean improvement in best-corrected visual acuity (BCVA) was 11.47 ± 5.56 letters. Remote OCT evaluations accounted for 194 scans, there was a high agreement between two expert in-hospital examinators (Cohen’s κ = 0.927) with only 14 cases requiring hospital visits for inconclusive results. Conclusions: Remote monitoring for RVO patients significantly reduced hospital admissions for follow-up visits, reducing the clinical burden on medical staff, patients, and caregivers, while maintaining reliable patient assessments. Full article

Objectives: This study aimed to investigate the possible relationship between aortic stenosis (AS) occupancy and the incidence of subsequent macular diseases. Methods: A retrospective cohort study was conducted using the TriNetX database, and participants with AS were enrolled and matched to non-AS participants. A total of 421,860 and 421,860 participants were evenly divided into the AS and non-AS groups, respectively. The major outcomes of the present study include the development of age-related macular degeneration (AMD), retinal vascular occlusion (RVO), epiretinal membrane (ERM), and central serous chorioretinopathy (CSC). Cox proportional hazard regression was utilized for statistical analysis. Results: There were 4426 and 3013 AMD events; 7315 and 4753 RVO events; 2780 and 1910 ERM events; and 113 and 64 CSC events in the AS and non-AS groups, respectively. According to the results of Cox proportional hazard regression analysis, the AS group demonstrated significantly higher incidences of all macular diseases, including AMD, RVO, ERM, and CSC, compared to the non-AS group (all p < 0.05). The cumulative probabilities of all macular diseases were significantly higher in the AS group than in the non-AS group (all p < 0.05). In the sensitivity analysis, the developmental risks of AMD were significantly higher in the AS group than in the non-AS group with all traits. Conclusions: This study determined that AS occupancy is related to a higher risk of developing macular diseases, which positively correlated to the disease time of AS. Full article

Intraocularly, fatty acid-binding protein 4 (FABP4) and 5 (FABP5) mainly originate from human ocular choroidal fibroblasts (HOCF), and human nonpigmented ciliary epithelium (HNPCE) cells have been suggested to be pivotally involved in intraocular pathophysiology. To elucidate the unidentified regulatory mechanisms of the gene expression and protein secretion of FABPs, the effects of glucose levels, fatty acids (FAs), and peroxisome proliferator-activated receptor (PPAR) modulators were studied. To elucidate the additional biological role of FABPs, laser choroidal neovascularization (CNV) in Fabp4^−/− and Fabp4/5^−/− mice was analyzed by fluorescein angiography. By changing glucose levels, the secretion and expression of FABP4 in HOCF were significantly upregulated, whereas the secretion and expression of FABP5 in HNPCE decreased. The administration of various FAs, particularly docosahexaenoic acid (DHA), markedly increased the expression and secretion of both FABPs. PPAR modulators also influenced the secretion and expression of FABPs. In vivo, wild-type retina exhibited evident CNV with high fluorescein intensity, while Fabp4^−/− retina showed reduced CNV formation and Fabp4/5^−/− retina displayed evident CNV along with vitreous leakage. These findings suggest that (1) the production and secretion of intraocular FABP4 and FABP5 are distinctly regulated by glucose levels, FAs, and PPARs; and (2) intraocular FABP4 and FABP5 are critical for inducing retinal neovascularization and maintaining the blood-aqueous barrier. Full article

Background/Objectives: To provide insight into populations at higher risk of COVID-19-related retinal vascular occlusion, we identified the baseline characteristics of COVID-19 patients and vaccine recipients who developed this condition by conducting a systematic review to summarize the findings and evaluate the current knowledge on this subject. Methods: An electronic search on the PubMed and Scopus databases was performed for relevant case reports or series regarding retinal vascular occlusion in patients with past or present COVID-19 infection or SARS-CoV-2 immunization. This study was conducted using a pre-determined protocol following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: A total of 34 studies were enrolled in this systematic review. A total of 21 patients (14 males, 66.7%) have been diagnosed with COVID-19 related retinal vein occlusion (RVO, mean age = 41.9 ± 10.3 years), and 15 patients (12 males, 80%) have been diagnosed with retinal artery occlusion (RAO, mean age = 56.9 ± 13.2 years). The time to RVO since COVID-19 infection or SARS-CoV-2 immunization ranged from 8 h to 51 days (mean = 12.3 ± 15.7 days), while the time to RAO ranged from 2 to 40 days (mean = 14.9 ± 10.8 days). Fifteen out of the twenty-one patients (71.4%) with RVO had a significant improvement in visual acuity after the resolution of symptoms while eight out of the fifteen patients (53.3%) with RAO did not show improvement. Conclusions: COVID-19 seems to play a significant role in the pathogenesis of vascular occlusion, as it is suggested to increase the risk of thromboembolic episodes. However, the pathophysiologic mechanisms have not been fully elucidated, and further studies are expected to shed light on this phenomenon. Full article

Background: Retinal diseases are emerging as a significant health concern, making early detection and prompt treatment crucial to prevent visual impairment. Optical coherence tomography (OCT) is the preferred imaging modality for non-invasive diagnosis. Both diabetic macular edema (DME) and macular edema secondary to retinal vein occlusion (RVO) present an increase in retinal thickness, posing etiologic diagnostic challenges for non-specialists in retinal diseases. The lack of research on deep learning classification of macular edema secondary to RVO using OCT images motivated us to propose a convolutional neural network model for this task. Methods: The VGG-19 network was fine-tuned with a public dataset to classify OCT images. This network was then used to develop three models: unimodal—the input is only the OCT B-scan; multimodal—the inputs are the OCT B-scan and diabetes information, and multi-image—the inputs are the OCT B-scan, the infrared image, and the diabetes information. Seven hundred sixty-six patients from ULS São João were selected, comprising 208 healthy eyes, 207 with macular edema secondary to RVO, 218 with DME, and 200 with other pathologies. The performance metrics include accuracy, precision, recall, F_0.5 score, and area under the receiver operating characteristic curve (AUROC). Results: The multi-image model achieved better results, with an accuracy of 95.20%, precision of 95.43%, recall of 95.20%, F_0.5-score of 95.32%, F₁-score of 95.21%, and AUROC of 99.59% on the classification task between four classes. Conclusions: This study presents a novel method to distinguish macular edema secondary to RVO and DME using diabetes diagnosis, OCT, and infrared images. This research aims to provide a reliable tool for ophthalmologists, improving the accuracy and speed of diagnoses. Full article

Objectives: This study aimed to predict the unknown etiology of fundus-obscuring vitreous hemorrhage (FOVH) based on preoperative conditions using machine learning (ML) and to identify key preoperative factors. Methods: Medical records of 223 eyes from 204 patients who underwent vitrectomy for FOVH of unknown etiology between January 2012 and July 2022 were retrospectively reviewed. Preoperative data, including demographic information, systemic disease, ophthalmic history, and retinal status of the unaffected eye, were collected. The postoperatively identified etiologies of FOVH were categorized into six groups: proliferative diabetic retinopathy (PDR), retinal vein occlusion (RVO) or rupture of retinal arterial macroaneurysm, neovascular age-related macular degeneration (nAMD), retinal tear, Terson syndrome, and other causes. Four ML algorithms were trained and evaluated using seven-fold cross-validation. Results: The ML algorithms achieved mean accuracies of 76.2% for artificial neural network, 74.5% for XG-Boost, 74.4% for LASSO logistic regression, and 68.5% for decision tree. Key predictive factors commonly selected by the ML algorithms included PDR in the fellow eye, underlying diabetes mellitus, subarachnoid hemorrhage, and a history of retinal tear, RVO, or nAMD in the affected eye. Conclusions: The unknown etiology of FOVH could be predicted preoperatively with considerable accuracy by ML algorithms. Previous ophthalmic conditions in the affected eye and the condition of the fellow eye were important variables for prediction. This approach might assist in determining appropriate treatment plans. Full article

We aimed to evaluate the accuracy and reproducibility of right ventricular output (RVO) using different anatomical landmarks: the internal pulmonary valve diameter (PVD) between the valve hinge points (hinge-PVD) according to the traditional technique, and PVD between the valve leaflet tips (tip-PVD). This was a retrospective analysis of prospective collected data. All neonates with echocardiographic measurements of RVO and left ventricular output (LVO) without congenital heart disease, including patent ductus arteriosus and patent foramen ovale > 3 mm, were included. Accuracy was assessed by comparison with LVO. Intra- and inter-observer reproducibility of the off-line analysis were assessed. Forty-five neonates were included. RVO calculation with tip-PVD was more accurate than hinge-PVD in comparison with LVO, r² 0.712 versus 0.464, bias (95% limits of agreement) 1.4 mL/kg/min (−26–29 mL/kg/min) versus 61 mL/kg/min (−11–132 mL/kg/min), respectively. Both hinge-PVD and tip-PVD presented similar reproducibility, with an intra-observer bias (95% LOA) of 0.3 (−1.0–0.5) and –0.2 (−0.8–0.5) respectively, and an inter-observer bias of 0.1 (−1.3–1.6) and 0.1 (−1.4–1.6). RVO calculation using tip-PVD was more accurate than the conventional technique, with similar reproducibility. Full article