Search Results (253)

Disorders of the cornea are responsible for a significant portion of preventable blindness worldwide. Various types of corneal transplantation procedures have successfully restored vision in many individuals; however, they carry the risk of graft failure due to immune rejection, endothelial cell dysfunction, infections and limbal stem cell deficiency. Thus, regenerative therapies of the cornea serve as promising alternatives or adjunct therapies. With improved understanding of limbal stem cell function and advancement in limbal stem cell culture technologies, major progress has been made in the in vivo and ex vivo cell-based therapies for treatment of corneal diseases. In this review, we summarize the recent developments achieved in cell-based therapeutics to target corneal epithelial, stromal, and endothelial cell disorders. Full article

Background/Objectives: An increasing number of older individuals require general anaesthesia for major non-cardiac surgery, with 20% displaying postoperative complications. Regional cerebral oxygen saturation (rSO₂) correlates with the gold standard of mixed venous oxygen saturation, indicating global perfusion. We hypothesised that rSO₂-based anaesthesia reduces organ dysfunction and morbidity after major non-cardiac surgery. Methods: In Singapore and Toronto, we conducted a prospective, double-blind, randomised controlled trial in elderly patients undergoing major non-cardiac surgery, after obtaining research ethics board permission and informed consent. This RCT followed the CONSORT guidelines. Patients received bilateral cerebral oximetry sensors, and the control group received standard care. In the intervention group, an algorithm restored rSO₂ if it dropped 10% below baseline for >15 s by adjusting cerebral perfusion pressure, inspired oxygen concentration, end-tidal carbon dioxide, depth of anaesthesia, haemoglobin, and cardiac index. Postoperative complications and outcomes were noted. Categorical data were analysed using Chi-square or Fisher’s exact tests and continuous data using a t-test or a Mann–Whitney U test. The study was powered for 394 patients, but due to the COVID-19 pandemic and funding constraints, this study was terminated at 101 patients. Results: Of 101 patients, 49 were randomised to the control and 52 to the intervention group. A total of 31 (63%) patients in the control group and 30 (58%) in the interventional exhibited bilateral cerebral desaturation. Time of cumulative cerebral desaturation was longer in the control group (23 ± 48 min vs. 9 ± 15 min, respectively, p = 0.01). A total of 142 algorithm-based treatments were employed, restoring rSO₂ in 29 (86%) patients. Both groups displayed equal postoperative outcomes. Conclusions: In major non-cardiac surgery, cerebral desaturation is prevalent in over 85% of patients. Although algorithm-guided therapy restored rSO₂ in the majority of patients, it did not result in reduced postoperative morbidity. Full article

Corneal endothelial dysfunction is a leading cause of vision impairment globally, traditionally managed through donor-dependent keratoplasty procedures. However, limitations in donor tissue availability, surgical complexity, and long-term graft survival have prompted the development of cell-based regenerative therapies. Among these, corneal endothelial cells (CECs) injection therapy has emerged as a minimally invasive alternative, offering the potential to restore endothelial function. This review provides a comprehensive analysis of recent advances in bioengineering strategies for CECs therapy, including cell sourcing from donor tissue, pluripotent stem cells, and transdifferentiated somatic cells; optimization of culture conditions and substrates; and delivery protocols that enhance cell adhesion and survival. We further examine clinical trial outcomes and propose future directions for clinical translation. The convergence of cell biology, biomaterials engineering, and translational medicine positions CECs injection therapy as a transformative solution to corneal blindness. Full article

Keratoconus is a potentially blinding condition characterized by progressive thinning and steepening of the cornea, leading to visual impairment due to irregular astigmatism and myopia. While the exact pathophysiology is still unknown, it is believed to involve genetic, environmental, and cellular factors. Treatment options for keratoconus have significantly expanded over the past few decades. Historically, glasses were the primary means of managing mild cases, whereas rigid gas permeable contact lenses were used in moderate to advanced diseases; yet the latter were rarely tolerated by patients with steep cones, in which full-thickness corneal transplantation was often performed. However, a variety of innovative treatments have been introduced in the past decades. Corneal collagen cross-linking (CXL) has revolutionized the field by halting the progression of keratoconus through creating new covalent bonds between individual corneal fibers. Custom, soft, and scleral contact lenses have improved visual outcomes for many patients. Additionally, surgical interventions such as intrastromal ring segments and Bowman layer transplantation have provided alternatives for visual restoration and postponing a potential keratoplasty. Furthermore, innovative cellular and pharmacological KCN treatments are on the horizon, awaiting clinical trials. This review article aims to provide a comprehensive overview of the current treatment options for keratoconus. Full article

This study proposes an image-enhancement method to address the challenges of low visibility and color distortion in images captured during yellow sandstorms for an image sensor based outdoor surveillance system. The technique combines traditional image processing with deep learning to improve image quality while preserving color consistency during transformation. Conventional methods can partially improve color representation and reduce blurriness in sand–dust environments. However, they are limited in their ability to restore fine details and sharp object boundaries effectively. In contrast, the proposed method incorporates Retinex-based processing into the training phase, enabling enhanced clarity and sharpness in the restored images. The proposed framework comprises three main steps. First, a cycle-consistent generative adversarial network (CycleGAN) is trained with unpaired images to generate synthetically paired data. Second, CycleGAN is retrained using these generated images along with clear images obtained through multiscale image decomposition, allowing the model to transform dust-interfered images into clear ones. Finally, color preservation is achieved by selecting the A and B chrominance channels from the small-scale model to maintain the original color characteristics. The experimental results confirmed that the proposed method effectively restores image color and removes sand–dust-related interference, thereby providing enhanced visual quality under sandstorm conditions. Specifically, it outperformed algorithm-based dust removal methods such as Sand-Dust Image Enhancement (SDIE), Chromatic Variance Consistency Gamma and Correction-Based Dehazing (CVCGCBD), and Rank-One Prior (ROP+), as well as machine learning-based methods including Fusion strategy and Two-in-One Low-Visibility Enhancement Network (TOENet), achieving a Blind/Referenceless Image Spatial Quality Evaluator (BRISQUE) score of 17.238, which demonstrates improved perceptual quality, and an Local Phase Coherence-Sharpness Index (LPC-SI) value of 0.973, indicating enhanced sharpness. Both metrics showed superior performance compared to conventional methods. When applied to Closed-Circuit Television (CCTV) systems, the proposed method is expected to mitigate the adverse effects of color distortion and image blurring caused by sand–dust, thereby effectively improving visual clarity in practical surveillance applications. Full article

Regenerative endodontic approaches for immature necrotic permanent teeth must balance biological efficacy, clinical practicality and long-term aesthetic outcomes. This study evaluates a novel regenerative protocol using autologous advanced platelet-rich fibrin plus (A-PRF+) scaffold sealed exclusively with glass ionomer cement (GIC) and compares it to conventional calcium hydroxide apexification used as the control. Twenty-eight patients were prospectively enrolled and followed for 12 months alongside a retrospectively selected historical control group. Outcomes were evaluated through standardised blinded clinical, radiographic and vitality assessments. The A-PRF+ protocol demonstrated significantly faster periapical healing, superior root lengthening, increased dentinal wall thickness and apical closure (p < 0.0001), with excellent aesthetic outcomes and no reported tooth discolouration. Pulpal blood flow measured by laser Doppler flowmetry indicated vitality restoration in 93% of cases. Preliminary linear regression identified treatment duration as a significant predictor of apical closure (p < 0.0001), with possible enhancement by additional patient-specific variables. These findings validate the A-PRF+ protocol as a highly effective, aesthetically favourable and predictable regenerative strategy, establishing a new benchmark for the management of immature necrotic teeth and laying the foundation for personalised predictive endodontic care. Future studies should include multicentre randomised controlled trials to confirm long-term clinical sustainability and generalisability. Full article

Background: Vitamin A deficiency (VAD) can occur due to malnutrition or reduced intestinal absorption, such as in short bowel syndrome (SBS). The main causes of SBS in adults include post-radiotherapy and surgery (e.g., repeated bowel resections). VAD mostly involves rods producing nyctalopia and reduced amplitudes of the electroretinogram (ERG) in scotopic conditions, with a characteristic negative ERG pattern (b/a < 1). Case Report: We report a 67-year-old woman with a history of gastric adenocarcinoma and several surgeries, who developed a progressive 3-month clinical picture of night blindness. Results: Urgent blood tests, biomicroscopy, intraocular pressure measurements, fundoscopy, and a cranial MRI were all normal. Visual evoked potentials showed increased latencies in both eyes, and full-field ERG showed a significant alteration in responses under scotopic conditions, and, to a lesser extent, under photopic conditions. Laboratory tests confirmed VAD, probably due to post-surgery and radiotherapy SBS. After parenteral vitamin replacement, VAD was clinically, analytically, and electroretinographically resolved. Discussion: VAD diagnosis is based on history, neuro-ophthalmological examination, and serum levels of retinol (<0.3 µg/mL) and/or retinol/retinol-binding protein (<0.8). In cases of a history of SBS, acquired nyctalopia, negative ERG, and clinical, analytical, and electroretinographic improvement with restoration of vitamin A levels, VAD should be suspected. ERG is crucial for early and appropriate management. Conclusions: As far as we know, this is the first reported VAD case secondary to SBS following surgical resections and radiotherapy of gastric adenocarcinoma with neuro-ophthalmological, laboratory, and electroretinographic monitoring of VAD recovery. Full article

Early-stage knee osteoarthritis (knee OA) lacks effective regenerative therapies. This study aimed to compare the cartilage regenerative effects, clinical efficacy, and safety of intra-articular injections of autologous adipose-derived mesenchymal stem cells (ADSCs) versus hyaluronic acid (HA). Forty-eight patients with early knee OA were enrolled in a prospective open-blinded multi-center study at Suranaree University of Technology Hospital and Phramongkutklao Hospital. Participants were randomized into either the ADSC or HA group. Primary outcomes included MRI-based cartilage lesion volume, synovial thickness via ultrasound, and WOMAC scores over 6 months. MRI results revealed significant and progressive cartilage regeneration in the ADSC group. In particular, medial femoral cartilage lesion volume decreased by 50.06 mm³, whereas the HA group showed an increase of 36.44 mm³. Synovial thickness also declined significantly in the ADSC group at 3 and 6 months. Both groups demonstrated reduced symptoms, but the ADSC group achieved superior and sustained improvements in WOMAC pain, stiffness, and function scores throughout the 6-month follow-up. The clinical benefits were consistent and more pronounced compared with HA. No serious adverse events occurred. In conclusion, intra-articular ADSC injections show superior cartilage restoration on MRI and better clinical outcomes than HA injection, making them a promising treatment for early-stage knee OA. Full article

Background: Glaucoma is a progressive optic neuropathy marked by retinal ganglion cells (RGCs), apoptosis, vascular insufficiency, oxidative stress, mitochondrial dysfunction, excitotoxicity, and neuroinflammation. While intraocular pressure (IOP) reduction remains the primary intervention, many patients continue to lose vision despite adequate pressure control. Emerging neuroprotective agents—citicoline, coenzyme Q10 (CoQ10), pyruvate, nicotinamide, pyrroloquinoline quinone (PQQ), homotaurine, berberine, and gamma-aminobutyric acid (GABA)—target complementary pathogenic pathways in experimental and clinical settings. Methods: This literature review synthesizes current evidence on glaucoma neuroprotection, specifically drawing on the most relevant and recent studies identified via PubMed. Results: Citicoline enhances phospholipid synthesis, stabilizes mitochondrial membranes, modulates neurotransmitters, and improves electrophysiological and visual field outcomes. CoQ10 preserves mitochondrial bioenergetics, scavenges reactive oxygen species, and mitigates glutamate-induced excitotoxicity. Pyruvate supports energy metabolism, scavenges reactive oxygen species, and restores metabolic transporter expression. Nicotinamide and its precursor nicotinamide riboside boost NAD⁺ levels, protect against early mitochondrial dysfunction, and enhance photopic negative response amplitudes. PQQ reduces systemic inflammation and enhances mitochondrial metabolites, while homotaurine modulates GABAergic signaling and inhibits β-amyloid aggregation. Berberine attenuates excitotoxicity, inflammation, and apoptosis via the P2X7 and GABA-PKC-α pathways. Preclinical models demonstrate synergy when agents are combined to address multiple targets. Clinical trials of fixed-dose combinations—such as citicoline + CoQ10 ± vitamin B3, citicoline + homotaurine ± vitamin E or PQQ, and nicotinamide + pyruvate—show additive improvements in RGCs’ electrophysiology, visual function, contrast sensitivity, and quality of life without altering IOP. Conclusions: A multi-targeted approach is suitable for glaucoma’s complex neurobiology and may slow progression more effectively than monotherapies. Ongoing randomized controlled trials are essential to establish optimal compound ratios, dosages, long-term safety, and structural outcomes. However, current evidence remains limited by small sample sizes, heterogeneous study designs, and a lack of long-term real-world data. Integrating combination neuroprotection into standard care holds promise for preserving vision and reducing the global burden of irreversible glaucoma-related blindness. Full article

Background: Immediate implant placement in the esthetic zone, particularly in Class II extraction sockets with partial facial bone loss, presents challenges in achieving soft and hard tissue stability. Customized computer-aided design/computer-aided manufacturing (CAD/CAM) titanium abutments may offer advantages over prefabricated stock abutments. This study compared the clinical, radiographic, and patient-reported outcomes of customized CAD/CAM titanium abutments versus stock Laser-Lok stock abutments. Materials and methods: In a single-center, double-blind randomized clinical trial, 48 patients received immediate maxillary anterior implants restored with either customized CAD/CAM titanium abutments (n = 24) or stock titanium abutments (n = 24). Primary outcomes included peri-implant probing depth (PD), mucosal height, Pink Esthetic Score (PES), crestal bone level changes, and patient satisfaction assessed at baseline, 6, and 12 months post-loading. Statistical analysis included effect sizes and 95% confidence intervals. Results: At 12 months, the customized abutment group showed significantly shallower PD (mean difference: −0.54 mm; 95% CI: −0.72 to −0.35; p < 0.001), higher PES (12.21 ± 0.35 vs. 10.41 ± 1.17; p < 0.0001; Cohen’s d = 2.08), and less crestal bone loss (1.75 ± 0.36 mm vs. 2.33 ± 0.52 mm; p < 0.0001). Patient satisfaction scores were also higher in the customized group (p = 0.003). Within-group improvements were observed in both groups over time. No implant failures occurred. Conclusions: At 1-year follow-up, customized CAD/CAM titanium abutments demonstrated improved peri-implant soft tissue parameters, esthetics, and patient satisfaction compared to stock abutments. While these findings support their use in esthetically demanding immediate implant cases, the short-term duration and single-center design warrant further long-term multicenter studies to confirm durability. Trial registration: Registered at ClinicalTrials.gov on 19/01/2025 (NCT06791655). Full article

Electrophysiological studies reveal significant organizational and functional differences in the cortex of blind individuals compared to sighted individuals. These differences result from the nervous system’s reorganization to adapt to new sensory modalities used in daily life. Cortical visual prostheses offer a means to restore visual sensations in blind individuals by generating phosphenes, luminous perceptions that provide information about their surroundings. This study investigates the cortical changes associated with the use of a visual neuroprosthesis, focusing on how the brain adapts to the restored visual input. Our findings aim to contribute to understanding neuroplasticity in sensory restoration processes. Full article

Gene therapy has emerged as a promising treatment for several eye diseases since it may restore vision and stop blindness. Many eye diseases, including retinitis pigmentosa and macular degeneration, have historically been rather difficult to treat and usually cause permanent vision loss. However, thanks to advances in gene therapy, many disorders can now be effectively targeted and genetically changed, providing a safer, more direct, maybe even curative approach. By introducing, altering, or repairing specific genes inside the eye, gene therapy seeks to fix the defective genes causing these disorders, thereby improving general eye health and visual ability. Voretigene neparvovec is one FDA- and EMA-approved treatment for RPE65 mutations. Retinitis pigmentosa, age-related macular degeneration, X-linked retinoschisis, choroideremia, and Stargardt disease are among the several eye disorders still under clinical trials, and experimental treatment is in progress. As research on gene therapy develops, it opens the path for groundbreaking treatments that could fundamentally change the ophthalmic care scene. Full article

Cataracts remain one of the leading causes of reversible blindness in low- and middle-income countries such as Ecuador. This study assessed the efficacy of Small Incision Cataract Surgery (SICS) and analyzed sociodemographic and clinical factors associated with postoperative visual outcomes. A retrospective multicenter analysis was conducted across six ophthalmology clinics along the Ecuadorian coast between 2023 and 2024, including 558 patients aged 30 years or older. Postoperative visual acuity, measured using the LogMAR scale, improved significantly (mean improvement of 0.525 LogMAR units in the right eye (OD) and 0.489 LogMAR units in the left eye; p < 0.001). Ages between 60 and 69 years were associated with better outcomes in the right eye, while male sex was a protective factor against poor visual acuity in the left eye. Although diabetes mellitus and hypertension were prevalent, neither condition showed a significant association with postoperative visual outcomes. The findings confirm that SICS is a safe, effective, and cost-efficient surgical approach for restoring vision in resource-limited settings, supporting its inclusion in national public health strategies to reduce avoidable blindness in developing countries. Full article

Age-related macular degeneration (AMD) is a common cause of blindness worldwide, and it is projected to affect several million individuals by 2040. The human retinal pigment epithelium (hRPE) degenerates in dry AMD, prompting the need to develop stem cell therapies to replace the lost tissue by autologous transplantation and restore the visual function. Nevertheless, the molecular factors behind the hRPE cell fate determination have not been elucidated. Here we identify all molecular determinants of the hRPE cell fate identity by comprehensive and unbiased screening of predicted pioneer factors in the human genome: such TFs mediate coordinated transitions in chromatin accessibility and transcriptional outcome along three major stages of the hRPE genesis. Furthermore, we compile a complete census of all transcription factor-specific binding sites by footprinting analysis of the human epigenome along the RPE developmental trajectory. Gene regulatory networks were found to be involved in cellular responses to glucose and hypoxia, RPE nitrosative stress, type II epithelial-to-mesenchymal transition (EMT), and type III tumorigenic EMT, providing routes for therapeutic intervention on pleiotropic targets dysregulated in AMD, diabetic retinopathy, and cancer progression. Genome editing technologies may leverage this repository to devise functional screenings of regulatory elements and pharmacogenomic therapies in complex diseases, paving the way for strategies in precision medicine. Full article

Cataracts, characterized by the opacification of the eye lens, remain a leading cause of reversible blindness globally. Age and diabetes are key risk factors, and with the increasing aging and diabetic population, the global burden of cataracts is projected to rise significantly. Current treatment is predominantly surgical; however, pharmacological strategies could offer a non-invasive alternative with the potential to delay, prevent, or even reverse cataract progression. Recent research has enhanced our understanding of cataractogenesis, emphasizing oxidative stress as a key underlying mechanism, but also including other processes such as calcium dysregulation and altered lens homeostasis or specific events induced by hyperglycemia in diabetic cataracts. New therapeutic approaches have emerged considering the molecular mechanisms involved in cataracts, most of which focus on pharmacological agents with antioxidant properties. Additionally, small-molecule chaperones, aldose reductase inhibitors, and protein aggregation inhibitors have also demonstrated potential in stabilizing or restoring lens protein structure and transparency. While experimental results have shown encouraging results, further research is needed to optimize drug delivery systems to the lens, assess long-term safety, and confirm the clinical efficacy of these treatments. This article reviews current progress in pharmacological treatments for cataracts, outlining challenges and prospects for future integration into clinical practice. Full article