Search Results (727)

Tissue-engineered scaffolds, particularly composite scaffolds composed of polymers combined with ceramics, bioactive glasses, or nanomaterials, play a vital role in regenerative medicine by providing structural and biological support for tissue repair. As scaffold designs grow increasingly complex, the need for non-invasive imaging modalities capable of monitoring scaffold integration, degradation, and tissue regeneration in real-time has become critical. This review summarizes current non-invasive imaging techniques used to evaluate tissue-engineered constructs, including optical methods such as near-infrared fluorescence imaging (NIR), optical coherence tomography (OCT), and photoacoustic imaging (PAI); magnetic resonance imaging (MRI); X-ray-based approaches like computed tomography (CT); and ultrasound-based modalities. It discusses the unique advantages and limitations of each modality. Finally, the review identifies major challenges—including limited imaging depth, resolution trade-offs, and regulatory hurdles—and proposes future directions to enhance translational readiness and clinical adoption of imaging-guided tissue engineering (TE). Emerging prospects such as multimodal platforms and artificial intelligence (AI) assisted image analysis hold promise for improving precision, scalability, and clinical relevance in scaffold monitoring. Full article

Background: Despite advances in coronary artery disease (CAD) treatment, challenges persist, particularly in complex lesions. While percutaneous coronary intervention (PCI) is widely used, its outcomes can be affected by complications like restenosis. Optical coherence tomography (OCT), offering higher-resolution imaging than angiography, shows promise in guiding PCI. However, meta-analytical comparisons between OCT-guided and angiography-guided PCI remain limited. Methods: Databases, including PubMed, Scopus, Cochrane Library, and ClinicalTrials.gov, were queried through May 2025 to identify randomized controlled trials (RCTs) comparing OCT-guided PCI with angiography-guided PCI. Data were pooled using risk ratios (RRs) and mean difference (MD) with 95% confidence intervals (CIs) in a random-effects model. Results: Five RCTs involving 5737 patients (OCT: 2738 and angiography: 2999) were included. On pooled analysis, OCT-guided PCI was associated with a notable reduction in major adverse cardiovascular event (MACE) (RR: 0.71, p = 0.0001), cardiac mortality (RR: 0.43, p = 0.003), target lesion revascularization (TLR) (RR: 0.53, p = 0.007), and stroke (RR: 0.17, p = 0.02), compared to angiography-guided PCI. No significant differences were noted for all-cause mortality and myocardial infarction. Conclusions: In patients with complex coronary lesions, OCT-guided PCI reduces the risk of MACE, cardiac mortality, TLR, and stroke, compared to angiography-guided PCI only. This study supports incorporating advanced imaging techniques like OCT to improve clinical outcomes, especially in complex PCIs. Full article

Background: Patients with primary angle-closure disease (PACD), those with no history of acute angle-closure glaucoma or laser iridotomy, rarely present with prominent corneal endothelial cell density (CECD) loss. To identify factors associated with decreased CECD in PACD, anterior segment parameters were compared in patients with PACD and normal CECD and patients with PACD and decreased CECD, using anterior segment optical coherence tomography (AS-OCT). Patients and Methods: Ten patients with PACD and CECD of less than 1500/mm² without a history of cataract surgery, acute angle-closure glaucoma, or prior laser glaucoma procedures were identified at the Kyorin Eye Center from January 2018 to July 2023. Patients with an obvious corneal guttata or apparent corneal edema were also excluded. Seventeen patients with PACD and normal CECD (normal CECD group) were used as the control. Simultaneous biometry of all anterior segment structures, including the cornea, anterior chamber, and iris, were assessed using a swept-source AS-OCT system. Results: Corneal curvature radius was significantly larger in the decreased CECD group compared with the corneal refractive power in the normal CECD group (p = 0.022, Mann–Whitney test). However, no significant differences were detected in other anterior segment morphology parameters. Multiple regression analysis with CECD as the dependent variable revealed that a large corneal curvature radius was a significant explanatory variable associated with corneal endothelial loss. Conclusions: Flattened corneal curvature may be a risk factor for corneal endothelial loss in patients with PACD. Full article

Background: Often, neoadjuvant therapy, which relies on the induction of double-strand breaks (DSBs), is used prior to surgery to shrink tumors by inducing cancer cell apoptosis. However, recent studies have suggested that this treatment may also induce a fluctuating state between senescence and stemness in PA-1 embryonal carcinoma cells, potentially affecting therapeutic outcomes. Thus, the respective epigenetic pathways are up or downregulated over a time period of days. These fluctuations go hand in hand with changes in spatial DNA organization. Methods: By means of Single-Molecule Localization Microscopy in combination with mathematical evaluation tools for pointillist data sets, we investigated the organization of euchromatin and heterochromatin at the nanoscale on the third and fifth day after etoposide treatment. Results: Using fluorescently labeled antibodies against H3K9me3 (heterochromatin tri-methylation sites) and H3K4me3 (euchromatin tri-methylation sites), we found that the induction of DSBs led to the de-condensation of heterochromatin and compaction of euchromatin, with a peak effect on day 3 after the treatment. On day 3, we also observed the co-localization of euchromatin and heterochromatin, which have marks that usually occur in exclusive low-overlapping network-like compartments. The evaluation of the SMLM data using topological tools (persistent homology and persistent imaging) and principal component analysis, as well as the confocal microscopy analysis of H3K9me3- and H3K4me3-stained PA-1 cells, supported the findings that distinct shifts in euchromatin and heterochromatin organization took place in a subpopulation of these cells during the days after the treatment. Furthermore, by means of flow cytometry, it was shown that the rearrangements in chromatin organization coincided with the simultaneous upregulation of the stemness promotors OCT4A and SOX2 and senescence promotors p21Cip1 and p27. Conclusions: Our findings suggest potential applications to improve cancer therapy by inhibiting chromatin remodeling and preventing therapy-induced senescence. Full article

Age-related ocular conditions like macular degeneration (AMD), diabetic retinopathy (DR), and glaucoma are leading causes of irreversible vision loss globally. Optical coherence tomography (OCT) provides essential non-invasive visualization of retinal structures for early diagnosis, but manual analysis of these images is labor-intensive and prone to variability. Deep learning (DL) techniques have emerged as powerful tools for automating the segmentation of the retinal layer in OCT scans, potentially improving diagnostic efficiency and consistency. This review systematically evaluates the state of the art in DL-based retinal layer segmentation using the PRISMA methodology. We analyze various architectures (including CNNs, U-Net variants, GANs, and transformers), examine the characteristics and availability of datasets, discuss common preprocessing and data augmentation strategies, identify frequently targeted retinal layers, and compare performance evaluation metrics across studies. Our synthesis highlights significant progress, particularly with U-Net-based models, which often achieve Dice scores exceeding 0.90 for well-defined layers, such as the retinal pigment epithelium (RPE). However, it also identifies ongoing challenges, including dataset heterogeneity, inconsistent evaluation protocols, difficulties in segmenting specific layers (e.g., OPL, RNFL), and the need for improved clinical integration. This review provides a comprehensive overview of current strengths, limitations, and future directions to guide research towards more robust and clinically applicable automated segmentation tools for enhanced ocular disease diagnosis. Full article

Background/Objectives: This study aimed to prospectively assess the incidence of retinal embolization and to evaluate the vascular and structural changes in the retina and choroid in 52 patients with asymptomatic severe carotid artery disease who underwent carotid artery revascularization. Methods: In our study, 35 patients underwent carotid endarterectomy (CEA) and 17 underwent carotid artery stenting (CAS). Biomicroscopy, fundoscopy, optical coherence tomography (OCT), and OCT-angiography (OCTA) were performed at baseline and 1 month after revascularization. Results: The subfoveal choroidal thickness (SFCT), peripapillary choroidal thickness inferior to the optic nerve head (ppCTi), total overall average retinal vascular density (rVDtot), and total overall average choriocapillaris vascular density (ccVDtot) of the eyes ipsilateral to the operated carotid artery increased significantly after revascularization, whereas a statistically significant increase was also found in the SFCT, rVDtot, and ccVDtot of the contralateral eyes in the overall cohort. Comparing the two study groups, we found that the SFCT, superior and inferior peripapillary choroidal thicknesses (ppCTs, ppCTi), rVDtot, and ccVDtot increased in both groups after revascularization, but significantly only in the CEA group. Furthermore, the temporal choriocapillaris vascular density (ccVDt) increased significantly after revascularization in both groups to a similar degree. Conclusions: Carotid artery revascularization led to a statistically significant increase in retinal and choroidal vascular densities, which indicates significantly improved ocular perfusion. The analysis of the findings of the two study groups suggests the superiority of CEA in terms of improving ocular perfusion in asymptomatic severe carotid artery disease. The rate of retinal embolization was similar in both surgical groups. Full article

Background: Optical Coherence Tomography has become a common imaging technique that enables a non-invasive and detailed visualization of the retina and allows for the identification of various diseases. Through the advancement of technology, the volume and complexity of OCT data have rendered manual analysis infeasible, creating the need for automated means of detection. Methods: This study investigates the ability of state-of-the-art object detection models, including the latest YOLO versions (from v8 to v12), YOLO-World, YOLOE, and RT-DETR, to accurately detect pathological biomarkers in two retinal OCT datasets. The AROI dataset focuses on fluid detection in Age-related Macular Degeneration, while the OCT5k dataset contains a wide range of retinal pathologies. Results: The experiments performed show that YOLOv12 offers the best balance between detection accuracy and computational efficiency, while YOLOE manages to consistently outperform all other models across both datasets and most classes, particularly in detecting pathologies that cover a smaller area. Conclusions: This work provides a comprehensive benchmark of the capabilities of state-of-the-art object detection for medical applications, specifically for identifying retinal pathologies from OCT scans, offering insights and a starting point for the development of future automated solutions for analysis in a clinical setting. Full article

Coronary plaque vulnerability, more than luminal stenosis, drives acute coronary syndromes. Optical coherence tomography (OCT), intravascular ultrasound (IVUS), and coronary computed tomography angiography (CCTA) visualize plaque morphology in vivo, but manual interpretation is time-consuming and operator-dependent. We performed a narrative literature survey of artificial intelligence (AI) applications—focusing on machine learning (ML) architectures—for automated coronary plaque segmentation and risk characterization across OCT, IVUS, and CCTA. Recent ML models achieve expert-level lumen and plaque segmentation, reliably detecting features linked to vulnerability such as a lipid-rich necrotic core, calcification, positive remodelling, and a napkin-ring sign. Integrative radiomic and multimodal frameworks further improve prognostic stratification for major adverse cardiac events. Nonetheless, progress is constrained by small, single-centre datasets, heterogeneous validation metrics, and limited model interpretability. AI-enhanced plaque assessment offers rapid, reproducible, and comprehensive coronary imaging analysis. Future work should prioritize large multicentre repositories, explainable architectures, and prospective outcome-oriented validation to enable routine clinical adoption. Full article

Hotpot dishes are widely favored by consumers for their flavor profiles developed during the cooking process. This study investigated the quality characteristics and volatile compounds (VOCs) of donkey meat slices across varying boiling durations (0–42 s) using gas chromatography–ion mobility spectrometry (GC-IMS). The results demonstrated that donkey meat boiled for 12–18 s exhibited optimal characteristics in terms of meat retention, color parameters, shear force values, and pH measurements. Forty-eight distinct VOCs were identified in the samples, with aldehydes, alcohols, ketones, acids, furans, and esters representing the predominant categories. Among these compounds, 18 were identified as characteristic aroma compounds, including 3-hexanone, 2, 3-butanedione, and oct-1-en-3-ol. Samples subjected to different boiling durations were successfully differentiated through topographic plots, fingerprint mapping, and multivariate analysis. The abundance and diversity of VOCs reached peak values in samples boiled for 12–18 s. Furthermore, 28 VOCs were identified as potential markers for distinguishing between different boiling durations, including 2-butoxyethanol D, benzaldehyde D, and (E)-2-pentenal D. This study concludes that a boiling duration of 12–18 s for donkey meat during hotpot preparation yields optimal quality characteristics and volatile flavor compound profiles and provides valuable insights for standardizing cooking parameters in hotpot preparations of other meat products. It is necessary to confirm this finding with sensory evaluations in further research. Full article

Coastal climate processes that affect landscape hydrology and beach dynamics are studied using local and remote data sets near Cape Vidal (28.12° S, 32.55° E). The sporadic intra-seasonal pulsing of coastal runoff, vegetation, and winds is analyzed to understand sediment inputs and transport by near-shore wind-waves and currents. River-borne sediments, eroded coral substrates, and reworked beach sand are mobilized by frequent storms. Surf-zone currents ~0.4 m/s instill the northward transport of ~6 10⁵ kg/yr/m. An analysis of the mean annual cycle over the period of 1997–2024 indicates a crest of rainfall over the Umfolozi catchment during summer (Oct–Mar), whereas coastal suspended sediment, based on satellite red-band reflectivity, rises in winter (Apr–Sep) due to a deeper mixed layer and larger northward wave heights. Sediment input to the beaches near Cape Vidal exhibit a 3–6-year cycle of southeasterly waves and rainy weather associated with cool La Nina tropical sea temperatures. Beachfront sand dunes are wind-swept and release sediment at ~10³ m³/yr/m, which builds tall back-dunes and helps replenish the shoreline, especially during anticyclonic dry spells. A wind event in Nov 2018 is analyzed to quantify aeolian transport, and a flood in Jan–Feb 2025 is studied for river plumes that meet with stormy seas. Management efforts to limit development and recreational access have contributed to a sustainable coastal environment despite rising tides and inland temperatures. Full article

Compared to widely used near-infrared OCT (NIR-OCT) systems, visible light OCT (vis-OCT) is an emerging imaging modality that leverages visible light to achieve high-resolution, high-contrast imaging and enables detailed spectroscopic analysis of biological tissues. In this review, we provide an overview of the state-of-the-art technology development and biomedical applications of vis-OCT. We also discuss limitations and future perspectives for advancing vis-OCT. Full article

Background/Objectives: This study evaluates whether ultrawide-field optical coherence tomography angiography (UWF-OCTA) can guide navigated laser therapy for non-perfused areas (NPAs) in branch retinal vein occlusion (BRVO). It further explores whether the laser spots can be accurately placed according to plan, considering that the retina is three-dimensional (3D), while UWF-OCTA provides two-dimensional (2D) images. Methods: UWF-OCTA images from three devices—VG200, Xephilio OCT-S1, and Bmizar—guided the treatments. These images were superimposed onto NAVILAS^® system images to guide NPA treatments. Pre-treatment planning was strategically designed to avoid normal and collateral vessels, with immediate post-laser OCTA and en face images assessing the efficacy of the laser spots in avoiding these vessels as planned. The accuracy of navigated laser therapy was further analyzed by comparing the intended laser locations with the actual spots. Results: All montaged OCTA images from the three devices were seamlessly integrated into the navigated laser system without registration errors. All patients received treatments targeting the NPAs as planned. However, not all collateral or normal vessels were successfully avoided by the laser spots. A further analysis revealed that the actual locations of the laser spots deviated slightly from the planned locations, particularly in the mid-periphery areas. Conclusions: UWF-OCTA-guided navigated laser photocoagulation is feasible and precise for treating NPAs in BRVO. Nonetheless, minor deviations between planned and actual locations were observed. This discrepancy, particularly important when treating diseases of the macular area, should be carefully considered when employing OCTA-guided navigated laser photocoagulation. Full article

Aminoglycoside antibiotics are critical in clinical use for treating severe infections, but they can occasionally cause irreversible sensorineural hearing loss. To establish a rational pathway for otoprotectant discovery, we provide an integrated, three-tier methodology—comprising cell-model selection, transcriptomic analysis, and a gentamicin–Texas Red (GTTR) uptake assay—to guide the development of otoprotective strategies. We first utilized two murine auditory cell lines—UB/OC-2 and HEI-OC1. We focused on TMC1 and OCT2 and further explored the underlying mechanisms of ototoxicity. UB/OC-2 exhibited a higher sensitivity to gentamicin, which correlated with elevated OCT2 expression confirmed via RT-PCR and Western blot. Transcriptomic analysis revealed upregulation of PI3K-Akt, calcium, and GPCR-related stress pathways in gentamicin-treated HEI-OC1 cells. Protein-level analysis further confirmed that gentamicin suppressed phosphorylated Akt while upregulating ER stress markers (GRP78, CHOP) and apoptotic proteins (cleaved caspase 3, PARP). Co-treatment with PI3K inhibitors (LY294002, wortmannin) further suppressed Akt phosphorylation, supporting the role of PI3K-Akt signaling in auditory cells. To visualize drug entry, we used GTTR to evaluate its applicability as a fluorescence-based uptake assay in these cell lines, which were previously employed mainly in cochlear explants. Sodium thiosulfate (STS) and N-acetylcysteine (NAC) significantly decreased GTTR uptake, suggesting a protective effect against gentamicin-induced hair cell damage. In conclusion, our findings showed a complex ototoxic cascade involving OCT2- and TMC1-mediated drug uptake, calcium imbalance, ER stress, and disruption of PI3K-Akt survival signaling. We believe that UB/OC-2 cells serve as a practical in vitro model for mechanistic investigations and screening of otoprotective compounds. Additionally, GTTR may be a simple, effective method for evaluating protective interventions in auditory cell lines. Overall, this study provides molecular-level insights into aminoglycoside-induced ototoxicity and introduces a platform for protective strategies. Full article

Glaucoma is a leading cause of irreversible blindness worldwide, yet early detection can prevent vision loss. This paper proposes a novel deep learning approach that combines two ophthalmic imaging modalities, fundus photographs and optical coherence tomography scans, as paired images from the same eye of each patient for automated glaucoma detection. We develop separate convolutional neural network models for fundus and optical coherence tomography images and a fusion model that integrates features from both modalities for each eye. The models are trained and evaluated on a private clinical dataset (Bangladesh Eye Hospital and Institute Ltd.) consisting of 216 healthy eye images (108 fundus, 108 optical coherence tomography) from 108 patients and 200 glaucomatous eye images (100 fundus, 100 optical coherence tomography) from 100 patients. Our methodology includes image preprocessing pipelines for each modality, custom convolutional neural network/ResNet-based architectures for single-modality analysis, and a two-branch fusion network combining fundus and optical coherence tomography feature representations. We report the performance (accuracy, sensitivity, specificity, and area under curve) of the fundus-only, optical coherence tomography-only, and fusion models. In addition to a fixed test set evaluation, we perform five-fold cross-validation, confirming the robustness and consistency of the fusion model across multiple data partitions. On our fixed test set, the fundus-only model achieves 86% accuracy (AUC 0.89) and the optical coherence tomography-only model, 84% accuracy (AUC 0.87). Our fused model reaches 92% accuracy (AUC 0.95), an absolute improvement of 6 percentage points and 8 percentage points over the fundus and OCT baselines, respectively. McNemar’s test on pooled five-fold validation predictions (b = 3, c = 18) yields ${\chi }^2=10.7$ (p = 0.001), and on optical coherence tomography-only vs. fused (b_o = 5, c_o = 20) ${\chi }_o^2=9.0$ (p = 0.003), confirming that the fusion gains are significant. Five-fold cross-validation further confirms these improvements (mean AUC $0.952\pm 0.011$. We also compare our results with the existing literature and discuss the clinical significance, limitations, and future work. To the best of our knowledge, this is the first time a novel deep learning model has been used on a fusion of paired fundus and optical coherence tomography images of the same patient for the detection of glaucoma. Full article

Objective: The clinical presentation of inherited retinal dystrophies associated with pathogenic variants in PRPH2 is highly variable. Here we present bilateral sector macular dystrophy as a novel clinical phenotype. Methods and analysis: Ophthalmologic examination, detailed retinal imaging with optical coherence tomography (OCT), OCT-angiography, fundus and near-infrared autofluorescence and molecular genetic testing were performed on a 30-year-old female. Results: The patient reported the onset of subjective visual disturbances 4.5 months prior to our first examination. Clinical examination and retinal imaging revealed bilateral sharply demarcated paracentral lesions in the temporal lower macula and otherwise normal retinal findings. Patient history revealed no medication or other possible causes for these unusual retinal lesions. Molecular genetic testing revealed a heterozygous c.623G>A variation (p.(Gly208Asp)) in the PRPH2 gene. Conclusions: Bilateral sectoral macular dystrophy has not been reported previously in any inherited retinal dystrophy. This feature adds to the wide spectrum of PRPH2-associated clinical presentations. Full article