Search Results (1,211)

Introduction: This pilot study aimed to test the feasibility of a novel vectorial image analysis method to quantify coronal microvascular displacement in different retinal plexuses in intermediate age-related macular degeneration (iAMD) over 6 months. Material and methods: A retrospective series of iAMD patients with at least 6-month follow-up was included if they had complete medical records, best-corrected visual acuity (BCVA), optical coherence tomography (OCT), and OCT angiography (OCTA). En-face (coronal) vascular displacement between baseline and 6 months was assessed in the superficial capillary plexus (SCP), deep capillary plexus (DCP), and choriocapillaris (CC) using the Farneback motion tracking algorithm applied to consecutive OCTA scans. Results: Eighteen eyes of 18 iAMD patients met the inclusion criteria. Average coronal vascular displacement (T₀–T₆) was 13.7 ± 7.72 µm for the SCP, 15.11 ± 10.06 µm for the DCP, and 19.02 ± 12.25 µm for the CC slab. Reticular pseudodrusen (RPD) was associated with greater displacement in the DCP (p = 0.047), but not in the SCP (p = 0.980) or CC (p = 0.473). Quantitative analysis confirmed the highest DCP displacement in RPD eyes (66.7%, p = 0.02), while drusenoid pigment epithelial detachment showed the greatest reorganization in the CC (100%, p = 0.02). Discussion: Retinal vessels undergo significant tangential displacement in iAMD, suggesting a structural reorganization of the microvasculature. Such remodeling may constitute a compensatory response to ultrastructural alterations resulting in ischemia. Full article

Optical coherence tomography (OCT) is a leading imaging technique for diagnosing retinal disorders such as age-related macular degeneration and diabetic retinopathy. Its ability to detect structural changes, especially in the optic nerve head, has made it vital for early diagnosis and monitoring. This paper surveys techniques for ocular disease prediction using OCT, focusing on both hand-crafted and deep learning-based feature extractors. While the field has seen rapid growth, a detailed comparative analysis of these methods has been lacking. We address this by reviewing research from the past 20 years, evaluating methods based on accuracy, sensitivity, specificity, and computational cost. Key diseases examined include glaucoma, diabetic retinopathy, cataracts, amblyopia, and macular degeneration. We also assess public OCT datasets widely used in model development. A unique contribution of this paper is the exploration of adversarial attacks targeting OCT-based diagnostic systems and the vulnerabilities of different feature extraction techniques. We propose a practical, robust defense strategy that integrates with existing models and outperforms current solutions. Our findings emphasize the value of combining classical and deep learning methods with strong defenses to enhance the security and reliability of OCT-based diagnostics, and we offer guidance for future research and clinical integration. Full article

Chimpanzees (Pan troglodytes) rescued from the illegal wildlife trade often suffer from chronic, traumatic injuries that require specialized and prolonged medical treatment in wildlife rehabilitation centers. We present the case report of a two-year-old male chimpanzee admitted at the Tchimpounga Chimpanzee Rehabilitation Center in the Republic of Congo with a chronic periorbital abscess, likely caused by a machete wound sustained during the poaching of his mother. Despite receiving extended antimicrobial therapy, his condition was never fully controlled and progressed to a chronic orbital infection, causing him discomfort and producing chronic purulent discharge. Enucleation was performed under general anesthesia using ketamine and medetomidine, with surgical approach adapted to the distinctive orbital anatomy of chimpanzees. During the procedure, ligation of the optic nerve and ophthalmic vessels was required due to the confined orbital apex and extensive vascularization, ensuring adequate haemostasias and procedural safety. The chimpanzee made an uneventful postoperative recovery, resuming normal feeding and social behavior within 48 h, with complete wound healing occurring within two weeks. This case report highlights the importance of prompt surgical intervention when conservative medical management fails to resolve refractory ocular infections in chimpanzees. It also emphasizes the importance of specific anesthetic protocols, refined surgical techniques and tailored postoperative care in wildlife rehabilitation centers. Documenting and sharing detailed case reports such as this contributes to the limited veterinary literature on great ape surgery and supports evidence-based clinical decision-making to improve the welfare and treatment outcomes of rescued chimpanzees. Full article

Persistent luminescence nanoparticles (PLNPs) represent a unique class of optical materials. They possess the ability to absorb and store energy from external excitation sources and emit light persistently once excitation terminates. Because of this distinctive property, PLNPs have attracted considerable attention in various areas. Especially in recent years, PLNPs have revealed marked benefits and extensive application potential in fields such as biological detection, imaging, targeted delivery, as well as integrated diagnosis and treatment. Not only do they potently attenuate autofluorescence interference arising from biological tissues, but they also demonstrate superior signal-to-noise ratio and sensitivity in in vivo imaging scenarios. Therefore, regarding the current research, this paper firstly introduces the classification, synthesis methods, and luminescence mechanism of the materials. Subsequently, the research progress of PLNPs in biological detection and imaging and medical treatment in recent years is reviewed. The challenges faced by materials in biomedical applications and the outlook of future development trends are further discussed, which delivers an innovative thought pattern for developing and designing new PLNPs to cater to more practical requirements. Full article

Background/Objectives: Borderline personality disorder (BPD) is a psychiatric disorder characterized by emotional instability, impulsive behavior, and impaired interpersonal relationships. It is associated with a high prevalence of childhood trauma and neurobiological changes. This study aimed to compare ophthalmologic parameters, namely, optic nerve sheath diameter, intraocular pressure, and dry eye, in patients with BPD with healthy controls and to investigate the relations between these parameters and childhood trauma. Methods: This study included 51 female patients with BPD between the ages of 18 and 35 years, who were not using psychotropic medication, and 51 healthy controls matched for age and educational level. Optic nerve sheath diameter, intraocular pressure, and tear break-up time were measured, and trauma history was evaluated using the Childhood Trauma Questionnaire-Short Form. Independent t-test and Pearson correlation analysis were used in statistical analyses. Results: Patients with BPD were found to have significantly higher mean optic nerve sheath diameter scores (left: 3.94 ± 0.43, right: 3.97 ± 0.47) compared with healthy controls (left: 3.76 ± 0.44, right: 3.78 ± 0.45) (p < 0.05). The groups showed no significant difference in intraocular pressure and dry eye parameters (p > 0.05). A significant positive correlation was noted between emotional abuse scores and the optic nerve sheath diameter of the left eye in patients with BPD (p < 0.05; r = 0.364). Conclusions: An increased optic nerve sheath diameter may be a potential peripheral biomarker reflecting chronic stress or changes in intracranial physiology in patients with BPD. This increase is particularly associated with a history of emotional abuse. Ophthalmological parameters may contribute to understanding the neurobiological basis of BPD and serve as peripheral biomarkers or indicators of neurobiological changes. Full article

Volatile organic compounds (VOCs) present in human exhaled breath have emerged as promising biomarkers for non-invasive disease diagnosis. However, traditional VOC detection technology that relies on large instruments is not widely used due to high costs and cumbersome testing processes. Machine learning-assisted gas sensor arrays offer a compelling alternative by enabling the accurate identification of complex VOC mixtures through collaborative multi-sensor detection and advanced algorithmic analysis. This work systematically reviews the advanced applications of machine learning-assisted gas sensor arrays in medical diagnosis. The types and principles of sensors commonly employed for disease diagnosis are summarized, such as electrochemical, optical, and semiconductor sensors. Machine learning methods that can be used to improve the recognition ability of sensor arrays are systematically listed, including support vector machines (SVM), random forests (RF), artificial neural networks (ANN), and principal component analysis (PCA). In addition, the research progress of sensor arrays combined with specific algorithms in the diagnosis of respiratory, metabolism and nutrition, hepatobiliary, gastrointestinal, and nervous system diseases is also discussed. Finally, we highlight current challenges associated with machine learning-assisted gas sensors and propose feasible directions for future improvement. Full article

Background/Objectives: Glaucoma refers to a group of eye diseases that damage the optic nerve, causing irreversible vision loss. It typically begins with peripheral vision impairment and, in severe cases, leads to complete blindness. A major advancement in glaucoma treatment is Microinvasive Glaucoma Surgery (MIGS), including trabecular bypass and ab interno trabeculectomy, which are generally used for mild to moderate glaucoma. This review aimed to evaluate the efficacy and safety of iStent micro-bypass implantation and Kahook Dual Blade (KDB) goniotomy combined with phacoemulsification in patients with open-angle glaucoma (OAG). Methods: A review of recent studies was conducted using PubMed, Google Scholar, Scopus, Web of Science, and Embase. Both prospective and retrospective clinical studies were included. These MIGS methods were compared for reducing intraocular pressure (IOP) and medication burden at baseline and endpoint. Results: Eleven studies involving 1925 eyes were analyzed. All studies showed that iStent (first- and second-generation) micro-bypass implantation and KDB goniotomy reduced IOP, favoring the phaco-KDB group. Antiglaucoma medication use also decreased significantly. The success rate was sufficient and most complications were minimal. Conclusions: In conclusion, iStent implantation and KDB goniotomy offer a high safety profile, meaningful IOP reduction, a minimally invasive approach, and quick recovery. Full article

This study investigates the effects of repeated cleaning, disinfection, and sterilization cycles on the surface and mechanical properties of medical-grade silicone, including both pure silicone and silicone–steel composite samples. Given the critical importance of sterilization for infection control, understanding its long-term impact on material performance is essential. Samples were subjected to up to 1000 cycles, with evaluations at the initial state and after 200, 500, and 1000 cycles. The contact angle initially decreased from 117.1° to 104.0° after 200 cycles, then gradually increased, approaching the original value after 1000 cycles, likely due to the removal of degraded surface layers. Hardness measurements showed a steady increase at each stage, with an approximate 5% rise per cycle group. Notch growth testing revealed a sixfold increase in crack length after 200 cycles and a twofold increase between 500 and 1000 cycles, indicating substantial loss of mechanical integrity. Optical microscopy of the silicone–steel interface revealed progressive deterioration, including crack formation, erosion, and partial debonding, particularly after 1000 cycles. These findings highlight the material and interfacial vulnerabilities of silicone-based medical devices under prolonged sterilization protocols. Full article

Ultrafast laser welding of glass/metal heterostructures has found extensive applications in sensors, medical devices, and optical systems. However, achieving high-stability, high-quality welds under non-optical contact conditions remains challenging due to severe internal damage within glass materials. This study addresses thermal management through synergistic control of thermal accumulation effects and material ablation thresholds. Using the sapphire/Invar alloy system as a model for glass/metal welding, we investigated thermal accumulation effects during ultrafast laser ablation of Invar alloy through theoretical simulations. Under a repetition rate of 1 MHz, the femtosecond laser raised the lattice equilibrium temperature by 700 K within 10 microseconds, demonstrating that high repetition rate femtosecond lasers can induce effective heat accumulation in Invar alloy. Furthermore, ablation thresholds for both materials were determined across varying repetition rates via the D² method, with corresponding threshold curves systematically constructed. Finally, based on the simulation and ablation threshold calculation results, laser parameters were selected for ultrafast laser single point welding of sapphire and Invar alloy. The experimental results demonstrate effective thermal effect mitigation, achieving a maximum shear strength of 63.37 MPa. Comparative analysis against traditional scan welding further validates the superiority of our approach in thermal management. This work provides foundational theoretical and methodological guidance for ultrafast laser welding of glass/metal heterostructures. Full article

Low vision is a condition in which a person experiences a significant loss of visual acuity or visual field that ordinary glasses, surgery, or medication cannot correct. Individuals suffering from this condition struggle to perform daily tasks, even when using glasses or contact lenses. In some cases, telescopes are recommended for patients with low vision diagnosis because they could help them improve their quality of life. Therefore, we propose a 3D-printed Galilean telescope for low-vision patients, accessible to both the vulnerable and nonvulnerable sectors of the population, with the advantages that the fabrication time, cost, and weight are considerably reduced. The performance of the 3D-printed Galilean telescope was evaluated by comparing it to an identical N-BK7 glass Galilean telescope design, obtaining a difference of 0.49 lp/mm in optical resolution. Clinical results from a patient with low vision, obtained as part of a proof-of-concept study, showed that the 3D-printed Galilean telescope improved the patient’s visual acuity, increasing it by up to 4 lines on the LEA numbers, from 10/80 to 10/32. Additionally, the 3D telescope enhanced the patient’s contrast sensitivity, improving it from 6 cpd (cycles per degree) level 8 to 18 cpd level 4. Full article

We reported on a generation of 27 nm spectral bandwidth, two-port output ultrashort pulses directly from an all-normal-dispersion passively mode-locked Yb-fiber laser. Based on the nonlinear polarization rotation (NPR) mode-locking technique, high pump power and optical devices with high damage thresholds were introduced to achieve broad spectral bandwidth and strong output power. The dual wavelengths were emitted from the clockwise and counterclockwise ports, respectively, and self-started mode-locking was achieved. The bidirectional output laser generates stable pulses with up to 223.5 mW average power at a 46.04 MHz repetition rate, corresponding to a pulse energy of 5 nJ. The bidirectional ultrashort outputs of the laser provide potential applications in supercontinuum generation and medical and biological applications. Full article

Ultraviolet (UV) and blue-light photodetectors are vital in environmental monitoring, medical and biomedical applications, optical communications, and security and anti-counterfeiting technologies. However, conventional silicon-based devices suffer from limited sensitivity to short-wavelength light due to their narrow indirect bandgap. In this study, we investigate the influence of precursor concentration on the structural, optical, and photoresponse characteristics of nanostructured CdS thin films synthesized via chemical bath deposition. Among the CdS samples prepared at different precursor concentrations, the best photoresponsivity of 21.1 mA/W was obtained at 2 M concentration. Subsequently, a p–n heterojunction photodetector was fabricated by integrating a spin-coated CuSCN layer with the optimized CdS nanostructure. The resulting device exhibited pronounced rectifying behavior with a rectification ratio of ~750 and an ideality factor of 1.39. Under illumination and a 5 V bias, the photodetector achieved an exceptional responsivity exceeding 10⁴ A/W in the UV region—over six orders of magnitude higher than that of CdS-based metal–semiconductor–metal devices. This remarkable enhancement is attributed to the improved light absorption, efficient charge separation, and enhanced hole transport enabled by CuSCN incorporation and heterojunction formation. These findings present a cost-effective, solution-processed approach to fabricating high-responsivity nanostructured photodetectors, promising for future applications in smart healthcare, environmental surveillance, and consumer electronics. Full article

Breast cancer is the leading cause of cancer-related mortality among women world-wide, and early screening is critical for improving patient survival. Medical imaging plays a central role in breast cancer screening, diagnosis, and treatment monitoring. However, conventional imaging modalities—including mammography, ultrasound, and magnetic resonance imaging—face limitations such as low diagnostic specificity, relatively slow imaging speed, ionizing radiation exposure, and dependence on exogenous contrast agents. Photoacoustic imaging (PAI), a novel hybrid imaging technique that combines optical contrast with ultrasonic spatial resolution, has shown great promise in addressing these challenges. By revealing anatomical, functional, and molecular features of the breast tumor microenvironment, PAI offers high spatial resolution, rapid imaging, and minimal operator dependence. This review outlines the fundamental principles of PAI and systematically examines recent advances in its application to breast cancer screening, diagnosis, and therapeutic evaluation. Furthermore, we discuss the translational potential of PAI as an emerging breast imaging modality, complementing existing clinical techniques. Full article

Background: This study aimed to evaluate prognostic factors of early filtering blebs using anterior segment swept-source optical coherence tomography (AS SS-OCT) in patients with uveitic and neovascular glaucoma. Methods: This retrospective cohort study included 22 eyes from 22 patients who underwent trabeculectomy (11 eyes each with uveitic or neovascular glaucoma). Intrableb characteristics were assessed using AS SS-OCT at 1 month, postoperatively. Surgical success was defined as intraocular pressure (IOP) ≤ 18 mmHg and ≥30% IOP reduction without medication at 12 months. Logistic regression was used to identify the prognostic factors associated with IOP control. Results: Sixteen eyes (72.7%) achieved surgical success, while six (27.3%) were unsuccessful. Eyes with successful IOP control at 12 months showed thicker and less reflective bleb walls with microcysts compared with unsuccessful cases of IOP control, in the early postoperative phase (all p < 0.033). However, IOP at the time of OCT did not significantly differ between the groups (p = 0.083). Multivariate logistic regression analysis revealed that higher bleb wall reflectivity at 1-month post-trabeculectomy was significantly associated with a higher surgical failure rate at 12 months after trabeculectomy (hazard ratio = 1.072, p = 0.032). Conclusions: Early intrableb assessment using AS SS-OCT may be beneficial for managing filtering blebs after trabeculectomy in uveitic and neovascular glaucoma. Higher bleb wall reflectivity in the early post-trabeculectomy phase may indicate poor features of the filtering bleb, suggesting the need for timely interventions for refractory cases. Full article

Plaque erosion (PE) is now recognized as a common and clinically significant cause of acute coronary syndromes (ACSs), accounting for up to 40% of cases. Unlike plaque rupture (PR), PE involves superficial endothelial loss over an intact fibrous cap and occurs in a low-inflammatory setting, typically affecting younger patients, women, and smokers with fewer traditional risk factors. The growing recognition of PE has been driven by high-resolution intracoronary imaging, particularly optical coherence tomography (OCT), which enables in vivo differentiation from PR. Identifying PE with OCT has opened the door to personalized treatment strategies, as explored in recent trials evaluating the safety of deferring stent implantation in selected cases in favor of intensive medical therapy. Given its unexpectedly high prevalence, PE is now recognized as a common pathophysiological mechanism in ACS, rather than a rare exception. This growing awareness underscores the importance of its accurate identification through OCT in clinical practice. Early recognition and a deeper understanding of PE are essential steps toward the implementation of precision medicine, allowing clinicians to move beyond “one-size-fits-all” models toward “mechanism-based” therapeutic strategies. This narrative review aims to offer an integrated overview of PE, tracing its epidemiology, elucidating the molecular and pathophysiological mechanisms involved, outlining its clinical presentations, and placing particular emphasis on diagnostic strategies with OCT, while also discussing emerging therapeutic approaches and future directions for personalized cardiovascular care. Full article