Search Results (2,863)

Background: Optical coherence tomography (OCT) is the main diagnostic technology used to detect damage to the retinal ganglion cells (RGCs) in glaucoma. However, it remains unclear which OCT parameter demonstrates the best diagnostic performance for eyes with early, especially preperimetric glaucoma (PPG). We determined the diagnostic performance of ganglion cell–inner plexiform layer (GCIPL) parameters using spectral-domain OCT (SD-OCT) in primary open-angle preperimetric and early perimetric glaucoma and compared them with optic nerve head (ONH) and peripapillary retinal nerve fiber layer (pRNFL) parameters. Methods: We analyzed 101 eyes: 36 normal eyes, 33 with PPG, and 32 with early perimetric glaucoma. All patients underwent Topcon SD–OCT imaging using the Optic Disc and Macular Vertical protocols. The diagnostic abilities of the GCIPL, rim area, vertical cup-to-disc ratio (CDR), and pRNFL were assessed using the area under the receiver operating characteristic curve (AUC). Results: For PPG, the AUCs ranged from 0.60 to 0.63 (GCIPL), 0.82 to 0.86 (ONH), and 0.49 to 0.75 (pRNFL). For early perimetric glaucoma, the AUCs for GCIPL and pRNFL ranged from 0.81 to 0.88 and 0.57 to 0.91, respectively, whereas both ONH parameters demonstrated an AUC of 0.89. The GCIPL parameters were significantly lower than both ONH parameters in detecting preperimetric glaucoma (p < 0.05). For early perimetric glaucoma, comparisons between the AUCs of the best-performing mGCIPL parameters and those of the best-performing pRNFL and ONH parameters revealed no significant differences in their diagnostic abilities (p > 0.05). Conclusions: GCIPL parameters exhibited a diagnostic performance comparable to that of ONH and pRNFL parameters for early perimetric glaucoma. However, their ability to detect preperimetric glaucoma was significantly lower than the ONH parameters. Full article

Background: This study aimed to evaluate the influence of scleral contact lens (SCL) wear on optical coherence tomography (OCT) scan quality and structural measurements in patients with keratoconus. Methods: This retrospective observational study included 28 eyes of 28 keratoconus patients. All participants underwent a comprehensive ophthalmologic evaluation, including corneal topography and spectral-domain OCT (Optopol REVO 60). Two OCT measurement sessions were performed on the same day: one without SCLs and one after a 30–75 min adaptation period with Mini Misa^® scleral lenses. Recorded parameters included corneal and epithelial thicknesses, ganglion cell–inner plexiform layer (GCIPL) thickness, retinal nerve fiber layer (RNFL) thickness, and device-reported quality index (QI). Correlation analyses between topographic values, age, and OCT parameters were also conducted. Results: The mean age of participants was 32.96 ± 13.72 years. SCL wear significantly decreased anterior segment QI (6.76 ± 1.73 vs. 5.57 ± 2.34, p = 0.019) but improved posterior segment QI in both the ganglion (2.52 ± 1.03 vs. 5.76 ± 2.17, p < 0.001) and disc (2.82 ± 0.94 vs. 4.39 ± 1.87, p < 0.001) modules. Central corneal thickness remained stable, while central epithelial thickness decreased slightly (50.53 ± 6.66 µm vs. 47.59 ± 7.20 µm, p = 0.007). RNFL and GCIPL thicknesses showed no significant changes, except for minor sectoral variations. Steeper keratometry values correlated with lower QI in both conditions. Conclusions: SCLs enhanced posterior OCT scan quality while reducing anterior segment image clarity. These findings suggest that SCLs not only provide visual rehabilitation but also facilitate more reliable posterior segment imaging in keratoconus patients, despite mild interference with anterior segment OCT metrics. Further prospective studies are warranted to validate these results. Full article

Objectives: To evaluate the relationship between hyperreflective dots (HRDs) observed on spectral-domain optical coherence tomography (SD-OCT) and the outcomes following treatment with intravitreal ranibizumab or dexamethasone injections in patients with diabetic macular edema (DME). Methods: This retrospective study focused on individuals suffering from diabetic macular edema (DME) who underwent a sequence of three intravitreal ranibizumab injections. Based on treatment response, the eyes were categorized into two groups: responders and non-responders. The non-responder group subsequently received intravitreal dexamethasone (IVO) implants. Treatment results were evaluated by changes in BCVA, HRD number, and central macular thickness (CMT). Results: This research involved 112 eyes from 78 participants who had been diagnosed with DME. Seventy-three eyes (65%) were identified as ranibizumab responders and 39 eyes (35%) as ranibizumab non-responders. Of the 39 individuals who had suboptimal response to ranibizumab and subsequently received treatment with an intravitreal dexamethasone implant, 26 eyes (66.67%) exhibited a favorable response, while 13 eyes (33.33%) showed an insufficient response. IVR responders demonstrated significantly greater improvements in BCVA (0.54 ± 0.73 to 0.35 ± 0.40 logMAR vs. 0.52 ± 0.61 to 0.47 ± 0.38 logMAR) and CMT (456.53 ± 109.73 μm to 235.47 ± 49.13 μm vs. 468.99 ± 127.10 μm to 427.45 ± 52.91 μm) reduction. Baseline analysis revealed IVR non-responders had higher counts of both inner and outer retinal HRDs compared to responders (9.09 ± 3.38 vs. 7.07 ± 2.32 and 5.46 ± 2.03 vs. 4.27 ± 1.87, p < 0.05, respectively). Eyes with initially higher numbers of inner retinal HRDs, outer retinal HRDs, and subretinal HRDs demonstrated a significantly enhanced response to dexamethasone therapy (9.03 ± 3.18 vs. 7.55 ± 2.72, 6.55 ± 2.46 vs. 4.79 ± 1.88 and 0.27 ± 0.54 vs. 0.21 ± 0.47, p < 0.05, respectively). Conclusions: HRDs could potentially be used as a predictive biomarker to assess the effectiveness of anti-VEGF therapy in treating DME. Patients exhibiting a greater number of retinal HRDs tend to have less favorable reactions to anti-VEGF treatments but experience improved results with dexamethasone. Full article

Background: Sturge–Weber syndrome (SWS) typically presents with a port-wine stain on the face, accompanied by leptomeningeal capillary malformations and ocular vascular anomalies. The aim of our study was to evaluate retinal vascular density and vessel diameter to better characterize the presence of vascular alterations. Methods: 15 patients diagnosed with Sturge–Weber syndrome and 15 healthy controls underwent comprehensive ophthalmologic evaluation, Optical Coherence Tomography (OCT) and Optical Coherence Tomography Angiography (OCTA), to evaluate the microvascular architecture of the retina and choroid. Results: Analysis of the processed images revealed a significant increase (p < 0.05 *) in the density of the deep capillary plexus in patients with SWS compared to healthy controls. Vascular diameter was found to be increased overall in several retinal vascular plexuses in SWS patients compared to controls, reaching statistical significance (p < 0.05 *) in the deep vascular complex. Conclusions: The findings from our analysis highlight the potential role of OCTA in predicting the progression or worsening of ocular diseases over time. The introduction of new assessment parameters offers additional perspectives in evaluating ocular health. Since this examination allows for the detection of changes in the morphology and density of blood vessels as revealed by OCTA, these changes can be correlated with disease progression and the effectiveness of therapies. Full article

Background/Objectives: Carbapenem-resistant Klebsiella pneumoniae (CRKP) threatens Intensive Care Units (ICU), particularly in settings where serine (KPC) and metallo-β-lactamases (NDM) co-circulate. The aim of this study was to assess CRKP susceptibility especially to novel β-lactam/β-lactamase inhibitor combinations, characterize the genetic determinants of resistance, and contribute to the understanding of local epidemiology in the ICU of our hospital. Methods: We studied 32 non-duplicate CRKP isolates (30 ICU, 2 wards) collected at Hippokration General Hospital, Thessaloniki (May–Oct 2023). Bacterial identification and Antimicrobial susceptibility testing (AST) were performed by VITEK-2; Minimum inhibitory concentrations (MICs) for ceftazidime/avibactam (CAZ/AVI), meropenem/vaborbactam (MER/VAB), and imipenem/relebactam (IMI/REL) were determined by E-tests. Colistin MICs were performed by broth microdilution. Carbapenemases were screened phenotypically and by immunochromatography and confirmed by multiplex PCR. One bronchial isolate co-harboring bla_NDM and bla_KPC genes underwent WGS. Results: All isolates were carbapenem-resistant and showed extensive resistance to β-lactams and fluoroquinolones. By PCR, 8/32 (25%) carried bla_KPC alone, 8/32 (25.0%) bla_NDM alone, and 16/32 (50%) co-harbored bla_KPC and bla_NDM. KPC-only isolates were generally susceptible in vitro to CAZ/AVI, MER/VAB, and IMI/REL, whereas dual KPC-NDM producers were resistant to all three combinations. Tigecycline showed the highest retained activity; colistin remained active in a minority. WGS of one ST512 (CG258) isolate revealed co-harboring bla_NDM-1 and bla_KPC-3 with additional resistance determinants and plasmid replicons, consistent with high-risk spread. Conclusions: Half of CRKP isolates in this ICU-predominant series co-produced KPC and NDM, severely limiting β-lactam/β-lactamase inhibitor options. These data support routine screening for carbapenemases, strict infection prevention, antimicrobial stewardship, and access to agents active against MBLs. Full article

Background: Optical Coherence Tomography (OCT) is a high-resolution imaging technique capable of quantifying Blood Flow at Depth (BD) and the Attenuation Coefficient (AC). However, the clinical relevance of these parameters in burn assessment remains unclear. This study investigated whether OCT-derived metrics can differentiate between superficial and deep pediatric hand burns. Method: This prospective, single-center study analyzed 73 OCT scans from 37 children with thermal hand injuries. A structured algorithm was used to evaluate AC and BD. Results: The mean AC was 1.61 mm⁻¹ (SD ± 0.48), with significantly higher values in deep burns (2.11 mm⁻¹ ± 0.53) compared to superficial burns (1.49 mm⁻¹ ± 0.38; p < 0.001), reflecting increased optical density in more severe burns. BD did not differ significantly between burn depths, although superficial burns more often showed visible capillary networks. Conclusions: This is the first study to assess both AC and BD using OCT in pediatric hand burns. AC demonstrated potential as a diagnostic marker for burn depth, whereas BD had limited utility. Image quality limitations highlight the need for technical improvements to enhance OCT’s clinical application. Full article

Background: Optical coherence tomography angiography (OCTA) enables non-invasive, high-resolution visualization of the retinal microvasculature and is increasingly utilized in pediatric ophthalmology. However, its clinical application in children is limited by the absence of age-specific normative data. Methods: In this cross-sectional study, macular vessel density (VD) and foveal avascular zone (FAZ) area were assessed in 118 healthy Caucasian children aged 4 to 17 years. OCTA scans were obtained using the OCT Topcon Triton^® device with 3 × 3 mm and 6 × 6 mm macular cubes. Vascular metrics from the superficial (SCP) and deep capillary plexuses (DCP) were analyzed in relation to demographic, refractive, biometric, and structural OCT parameters. Correlation and multivariate linear regression analyses were performed to evaluate associations. Results: Age-stratified reference percentiles for macular VD and FAZ area in SCP and DCP are presented for 118 children. Key associations included: (1) Increased macular thickness correlated with higher VD in the fovea and inner ring (SCP and DCP, all p < 0.05); (2) Thicker maculas were associated with smaller FAZ areas (SCP: r = −0.72, DCP: r = −0.58, both p < 0.001); (3) Older age was linked to reduced VD in the inner macular ring and smaller FAZ area (SCP and DCP, all p < 0.001); and (4) longer axial length correlated with lower central VD (SCP: r = −0.27, DCP: r = −0.37, both p < 0.05). No significant sex-based differences were observed. Conclusions: This study provides normative OCTA data for macular VD and FAZ area in healthy Caucasian children and identifies key associations with ocular parameters. These findings support improved diagnostic accuracy and clinical decision-making in pediatric retinal evaluation. Full article

A vision-based autonomous system for emasculating okra enhances agriculture by enabling precise flower bud identification, overcoming the labor-intensive, error-prone challenges of traditional manual methods with improved accuracy and efficiency. This study presents a framework for an adaptive, automated bud identification method to assist the emasculation process, hybridized optical coherence tomography (OCT). Three YOLOv8 variants were evaluated for accuracy, detection speed, and frame rate to identify the most efficient model. To strengthen the findings, YOLO was hybridized with OCT, enabling non-invasive sub-surface verification and precise quantification of the emasculated depth of both sepal and petal layers of the flower bud. To establish a solid benchmark, gold standard color histograms and a digital imaging-based method under optimal lighting conditions with confidence scoring were also employed. The results demonstrated that the proposed method significantly outperformed these conventional frameworks, providing superior accuracy and layer differentiation during emasculation. Hence, the developed YOLOv8 hybridized OCT method for flower bud identification and emasculation offers a powerful tool to significantly improve both the precision and efficiency of crop breeding practices. This framework sets the stage for implementing scalable, artificial intelligence (AI)-driven strategies that can modernize and optimize traditional crop breeding workflows. Full article

Cataract surgery is the most common eye operation worldwide and is regarded as one of the safest procedures in medicine. Yet, despite its low complication rates, it generates a disproportionate share of litigation. The gap between excellent safety profiles and rising medico-legal claims is driven less by surgical outcomes than by patient expectations, often shaped by healthcare marketing and the promise of risk-free recovery. This narrative review explores the clinical and legal dimensions of cataract surgery, focusing on complications, perioperative risk factors, and medico-legal concepts of predictability and preventability. Particular emphasis is given to European frameworks, with the Italian Gelli-Bianco Law (Law No. 24/2017) providing a model of accountability that balances innovation and patient safety. Analysis shows that liability exposure spans all phases of surgery: preoperative (inadequate consent, poor documentation), intraoperative (posterior capsule rupture, zonular instability), and postoperative (endophthalmitis, poor follow-up). Practical strategies for risk reduction include advanced imaging such as macular OCT, rigorous adherence to updated guidelines, systematic video recording, and transparent perioperative communication. Patient-reported outcomes further highlight that satisfaction depends more on visual quality and dialogue than on spectacle independence. By translating legal principles into clinical strategies, this review offers surgeons actionable “surgical–legal pearls” to improve outcomes, strengthen patient trust, and reduce medico-legal vulnerability in high-volume cataract surgery. Full article

Physical activity has been shown to influence ocular health, yet the acute effects of exercise on retinal and choroidal structures remain underexplored. This prospective pre-post study evaluated 30 low-fit adults without diagnosed cardiovascular disease who underwent comprehensive ophthalmologic assessments, including OCT and OCTA imaging, before and after a submaximal aerobic capacity test. Statistically significant thinning was observed in specific retinal sectors, affecting both inner and outer layers, including the retinal pigment epithelium (RPE). Vascular analysis using the OCTAVA toolbox revealed a significant post-exercise reduction in vessel length density, total vessel length, branchpoint density and fractal dimension in the peripapillary plexus; and mean tortuosity in the macular superficial vascular complex (SVC). Choroidal thickness also showed a significant reduction in several regions. No significant changes were found in the foveal avascular zone (FAZ). These findings suggest that acute submaximal physical activity induces transient yet measurable changes in retinal and choroidal microvasculature. The results have potential implications for understanding ocular vascular dynamics and for evaluating ocular health in clinical and sports medicine contexts. Full article

Background: Age-related macular degeneration is a major cause of vision loss, and improved visualization of macular neovascularization (MNV) on OCT angiography (OCTA) could enhance clinical assessment. This study aimed to establish a simple and accessible image enhancement method. Methods: We retrospectively analyzed 24 eyes from 22 patients with MNV at the Doheny UCLA Eye Centers. Grayscale-inverted OCTA images were generated using the basic “Invert” function in ImageJ 1.51 23. Each original and inverted image pair was assessed for seven MNV-related features: structure and area within 3 × 3 mm, 6 × 6 mm and 12 × 12 mm scans, and presence of polypoidal lesions. Twenty-one ophthalmologists graded visibility using a standardized five-point scale. Paired comparisons were performed using the Wilcoxon signed-rank test. Results: Grayscale inversion significantly improved the visualization of MNV structure in 6 × 6 mm scans (mean difference: +0.67 ± 1.02; p = 0.008), 12 × 12 mm scans (+0.62 ± 1.07; p = 0.013), and detection of polypoidal lesions (+0.43 ± 0.98; p = 0.030). No significant differences were found for 3 × 3 mm structure (p = 0.793) or area-related features (all p > 0.3). Conclusions: Grayscale inversion may enhance MNV visibility and polypoidal lesion detection on OCTA. As this study relied solely on subjective assessments, future work should incorporate quantitative image analysis. Full article

Purpose: This study sets out to analyze the correlation of ET-1, a vasoactive peptide, along with various cytokines and vascular factors, with clinical parameters and OCT/OCT-A measurements in glaucoma participants. Methods: Eyes of participants with cataract (n = 30) or glaucoma (n = 87) were examined with optical coherence tomography (OCT) and OCT angiography (OCT-A). Aqueous humor (AqH) from the examined eye and plasma were sampled during cataract or glaucoma surgery and analyzed by means of ELISA and Luminex assay to determine their levels of ET-1 and 35 proteins deemed relevant for regulation of the AqH outflow pathway, ocular perfusion (OP), and glucose metabolism. Results: Glaucomatous eyes are characterized by reductions in RNFL thickness and OP, reflected by reduced vessel density. Furthermore, significantly elevated peripheral ET-1 levels were detected in participants with glaucoma. In addition, significantly elevated AqH levels of MMP-2, MMP-3, ET-1, sEMMPRIN, ZAG, sLOX-1, follistatin, cortisol, endostatin, sTIE-2, and PDGF-BB were detected in the glaucomatous eyes, with correlation to reduced VD for APN, C3a, MMP-3, resistin, sTIE-2, and ZAG. Multivariable analysis showed a correlation of AqH APN levels with the reduced VD in glaucomatous eyes. Conclusions: The peripheral ET-1 level and the intraocular levels of APN, C3a, MMP-3, resistin, sTIE-2, and ZAG are associated with impaired OP in glaucoma. Furthermore, elevated intraocular levels of MMP-3, ZAG, and APN were identified as biomarkers for impaired perfusion in glaucoma. Full article

Glioblastoma (GBM) remains the most lethal primary brain tumor, owing to profound intratumoral heterogeneity and the limited efficacy of standard treatments. The mesenchymal (MES) molecular subtype is particularly aggressive, exhibiting heightened invasiveness, therapy resistance, and dismal patient survival compared with the proneural (PN) subtype. Emerging evidence implicates the High Mobility Group Box 1 (HMGB1) protein and its cognate receptor, the Receptor for Advanced Glycation End Products (RAGE), as drivers of malignant progression, yet their contribution to the PN-to-MES transition is incompletely defined. We integrated transcriptomic analyses of TCGA-GBM and TCGA-LGG cohorts with immunohistochemistry on in-house patient specimens. Functional studies in patient-derived and established GBM cell lines included migration and invasion assays, tumorsphere formation assays, shRNA knockdowns, and Seahorse XF metabolic profiling to interrogate the HMGB1-RAGE axis. HMGB1 and RAGE expression was markedly elevated in MES GBM tissues and cell lines. Importantly, higher HMGB1 expression correlated with shortened overall survival (p < 0.009). HMGB1 silencing curtailed cell motility and downregulated core epithelial-to-mesenchymal transition markers (N-cadherin, Snail). RAGE knockdown diminished tumorsphere formation efficiency and reduced transcription of stemness genes (OCT4), underscoring its role in sustaining tumor-initiating capacity. Metabolically, HMGB1/RAGE activation boosted both mitochondrial respiration and glycolysis, conferring the bioenergetic flexibility characteristic of MES GBM. The HMGB1-RAGE signaling axis orchestrates mesenchymal identity, invasiveness, stem cell-like properties, and metabolic reprogramming in GBM. Targeting this pathway may disrupt the PN-to-MES transition, mitigate therapeutic resistance, and ultimately improve outcomes for glioblastoma patients. Full article

Retinal vasculature is essential for maintaining visual function by supporting metabolically active neurons. However, the retina lacks redundant blood supply, rendering it highly susceptible to vascular dysfunction. Understanding mechanisms of retinal vascular abnormalities is critical for therapies that preserve vascular and neuronal integrity, yet progress has been hindered by limited models and genetic diversity. To address this gap, we examined the retinal vasculature in multiple aged strains from the BXD recombinant inbred mouse panel, a genetically diverse, tractable, and physiologically relevant platform for uncovering novel genetic drivers and disease mechanisms. We identified BXD32 as a striking outlier with dramatically reduced vessel density. Using optical coherence tomography, optical coherence tomography angiography, and histological analyses, we comprehensively characterized retinal vasculature and structural integrity of BXD32 mice during aging. We found progressive, age-dependent vascular dysfunction and degeneration, beginning in the deep capillary plexus and advancing to the intermediate and superficial layers. These changes were accompanied by neuronal degeneration, including photoreceptor loss and thinning of the ganglion cell complex. Our findings establish BXD32 as a spontaneous and genetically tractable model of inherited retinal neurovascular degeneration and provide a foundation for future studies to identify causative genetic loci and underlying molecular mechanisms. Full article

Uveal melanoma is the most common primary intraocular malignancy in adults, most frequently arising from the choroid, followed by the ciliary body and iris. Its diagnosis and management require precise characterization of tumor morphology, localization, and associated complications to optimize visual and systemic outcomes. Recent advances in optical coherence tomography (OCT), anterior segment OCT (AS-OCT), and OCT angiography (OCTA) have expanded the ophthalmologist’s ability to non-invasively visualize structural and vascular changes associated with this disease. In fact, enhanced depth imaging (EDI) and swept-source (SS) OCT can provide detailed views of deep ocular structures, enabling early detection of hallmark features such as subretinal fluid, retinal pigment epithelium disruption, and dome- or mushroom-shaped choroidal elevations; AS-OCT improves evaluation of lesions of the anterior segment, revealing iris architecture distortion and angle involvement; OCTA facilitates the visualization of abnormal tumor vasculature and detection of radiation-induced microvascular changes, including capillary dropout and foveal avascular zone enlargement. Moreover, these imaging modalities have demonstrated utility in differentiating uveal melanoma from pseudomelanomas, such as choroidal nevi, hemangiomas, and metastases. The present review aims at objectively assessing the use of OCT and OCTA in the diagnosis, treatment, and follow up of ocular melanoma, emphasizing their crucial role in identifying pathologic biomarkers of this potentially fatal ocular disease. Full article