Lipopeptide-mediated Cas9 RNP delivery: A promising broad therapeutic strategy for safely removing deep-intronic variants in ABCA4

Deep-intronic (DI) variants represent approximately 10%-12% of disease-causing genetic defects in ABCA4-associated Stargardt disease (STGD1). Although many of these DI variants are amenable to antisense oligonucleotide-based splicing-modulation therapy, no treatment is currently available. These molecules are mostly variant specific, limiting their applicability to a broader patient population. In this study, we investigated the therapeutic potential of the CRISPR-Cas9 system combined with the amphipathic lipopeptide C18:1-LAH5 for intracellular delivery to correct splicing defects caused by different DI variants within the same intron. The combination of these components facilitated efficient editing of two target introns (introns 30 and 36) of ABCA4 in which several recurrent DI variants are found. The partial removal of these introns did not affect ABCA4 splicing or its expression levels when assessed in two different human cellular models: fibroblasts and induced pluripotent stem cell-derived photoreceptor precursor cells (PPCs). Furthermore, the DNA editing in STGD1 patient-derived PPCs led to a ∼50% reduction of the pseudoexon-containing transcripts resulting from the c.4539+2001G>A variant in intron 30. Overall, we provide proof-of-concept evidence of the use of C18:1-LAH5 as a delivery system for therapeutic genome editing for ABCA4-associated DI variants, offering new opportunities for clinical translation.

Zotarolimus alleviates post-trabeculectomy fibrosis via dual functions of anti-inflammation and regulating AMPK/mTOR axis

OBJECTIVE

Postoperative scar formation is the primary cause of uncontrolled intraocular pressure following trabeculectomy failure. This study aimed to evaluate the efficacy of zotarolimus as an adjuvant anti-scarring agent in the experimental trabeculectomy.

METHODS

We performed differential gene and Gene Ontology enrichment analysis on rabbit follicular transcriptome sequencing data (GSE156781). New Zealand white Rabbits were randomly assigned into three groups: Surgery only, Surgery with mitomycin-C treatment, Surgery with zotarolimus treatment. Rabbits were euthanized 3 days or 28 days post-trabeculectomy. Pathological sections were analyzed using immunohistochemistry, immunofluorescence, and Masson staining. In vitro, primary human tenon's capsule fibroblasts (HTFs) were stimulated by transforming growth factor-β1 (TGF-β1) and treated with either mitomycin-C or zotarolimus. Cell proliferation and migration were evaluated using cell counting kit-8, cell cycle, and scratch assays. Mitochondrial membrane potential was detected with the JC-1 probe, and reactive oxygen species were detected using the DCFH-DA probe. RNA and protein expressions were quantified using RT-qPCR and immunofluorescence.

RESULTS

Transcriptome sequencing analysis revealed the involvement of complex immune factors and metabolic disorders in trabeculectomy outcomes. Zotarolimus effectively inhibited fibrosis, reduced proinflammatory factor release and immune cell infiltration, and improved the surgical outcomes of trabeculectomy. In TGF-β1-induced HTFs, zotarolimus reduced fibrosis, proliferation, and migration without cytotoxicity via the dual regulation of the TGF-β1/Smad2/3 and AMPK/AKT/mTOR pathways.

CONCLUSION

Our study demonstrates that zotarolimus mitigates fibrosis by reducing immune infiltration and correcting metabolic imbalances, offering a potential treatment for improving trabeculectomy surgical outcomes.

Small molecule SIRT1 activators counteract oxidative stress-induced inflammasome activation and nucleolar stress in retinal degeneration

BACKGROUND

The nicotinamide adenosine dinucleotide-dependent deacetylase Sirtuin 1 (SIRT1) has been identified as a protective factor that inhibits the activation of nucleotide-binding and oligomerization domain-, leucine-rich repeat-, and pyrin domain-containing protein 3 (NLRP3) inflammasome. However, whether pharmacological SIRT1 activators can protect retinal pigment epithelial (RPE) cells against oxidative and inflammatory injuries related to age-related macular degeneration remains to be explored.

METHODS

Two small molecule specific SIRT1 activators (SRT2104 and CAY10602) were tested, with resveratrol being used as a positive control. Mouse models with sodium iodate-induced retinal degeneration were constructed. ARPE-19 cells in culture were used for in vitro experiments. The effects of SIRT1 activators on H2O2-induced ARPE-19 cell injury were determined by reactive oxygen species quantification, western blotting, flow cytometry and immunofluorescence staining. In vivo, the severity of retinal damage was assessed using flash electroretinography and histopathological analysis.

RESULTS

In vitro, SRT2104, CAY10602 and resveratrol significantly attenuated H2O2-induced cell death, nucleolar stress response, and reactive oxygen species accumulation. In H2O2-stimulated cells, SIRT1 activators reduced the level of NLRP3, inhibited the activation of caspase-1, and decreased the production of interleukin (IL)-1β and IL-18. The inhibitory effects of SIRT1 activators on caspase-1 activation and IL-1β production were blunted by SIRT1 gene silencing. In vivo, treatment with SRT2104 or CAY10602 in mice with sodium iodate-induced retinal degeneration markedly improved the retinal functions and reduced the loss of RPE cells.

CONCLUSION

Our study suggests that small molecule SIRT1 activators are effective for protection of RPE cells against oxidative stress-induced NLRP3 inflammasome activation, highlighting potential applications in the treatment of macular degeneration associated RPE dysfunctions.

Underlying mechanisms of traditional Chinese medicine in the prevention and treatment of diabetic retinopathy: Evidences from molecular and clinical studies

As one of the most serious microvascular complications of diabetes mellitus (DM), diabetic retinopathy (DR) can cause visual impairment and even blindness. With the rapid increase in the prevalence of DM, the incidence of DR is also rising year by year. Preventing and effectively treating DR has become a major focus in the medical field. Traditional Chinese medicine (TCM) has a wealth of experience in treating DR and has achieved significant results with various herbs and TCM prescriptions. Traditional Chinese Medicine (TCM) provides a comprehensive therapeutic strategy for diabetic retinopathy (DR), encompassing anti-inflammatory and antioxidant actions, anti-neovascularization, neuroprotection, regulation of glucose metabolism, and inhibition of apoptosis. This review provides an overview of the current status of TCM treatment for DR in recent years, including experimental studies and clinical researches, to explore the clinical efficacy and the underlying modern mechanisms of herbs and TCM prescriptions. Besides, we also discussed the challenges TCM faces in treating DR, such as drug-drug interactions among TCM components and the lack of high-quality evidence-based medicine practice, which pose significant obstacles to TCM's application in DR.

Bone morphogenetic protein 4 inhibits corneal neovascularization by blocking NETs-induced disruption to corneal epithelial barrier

Corneal neovascularization (CoNV) is the second leading cause of visual impairment worldwide, and current drugs have certain limitations. Inflammatory response is the core pathological process of CoNV. Neutrophil extracellular traps (NETs) are generated after neutrophil activation, which promotes neovascularization. Prior studies demonstrated that bone morphogenetic protein 4 (BMP4) could significantly reduce inflammation and CoNV formation, its exact molecular mechanism remains unclear. Therefore, we stimulated human peripheral blood neutrophils with phorbol myristate acetate (PMA) or deoxyribonuclease I (DNase I) to induce or inhibit NETs formation. By using corneal sutures and subconjunctival injections of NETs or DNase I, rat CoNV models were established. Compared with the suture group, NETs formation and inflammatory cell infiltration in the corneal stroma were significantly increased, corneal edema was aggravated, and the length, area and diameter of CoNV were significantly enhanced in the NETs group. Furthermore, by curetting the corneal epithelial apical junctional complexes (AJCs), a crucial component in preserving the function of the corneal epithelial barrier, we discovered that the damage of AJCs had a significant role in inducing CoNV formation. NETs could induce CoNV formation by injuring corneal epithelial AJCs. Finally, by comparing the aforementioned indicators after the intervention of BMP4, BMP4 inhibitor Noggin and NADPH oxidase (NOX) inhibitor, we finally demonstrated that BMP4 could inhibit NETs-induced inflammation and corneal epithelial AJC injury, repair corneal epithelial barrier function and eventually inhibit CoNV formation by blocking NOX-2-dependent NETs formation.

Salidroside alleviates ferroptosis in FAC-induced Age-related macular degeneration models by activating Nrf2/SLC7A11/GPX4 axis

INTRODUCTION

Age-related macular degeneration (AMD) is a significant contributor to irreversible impairment in visual capability, particularly in its non-neovascular (dry) form. Ferroptosis, an emerging form of programmed necrosis, involves generating lipid peroxidation (LOS) through free iron and reactive oxygen species (ROS). Salidroside, a glycoside from Rhodiola rosea, known for anti-inflammatory and antioxidant properties. The research aim was exploring whether ferroptosis exists in dry AMD pathogenesis and elucidate salidroside's protective mechanisms against ferroptosis in AMD murine models and ARPE-19 cells.

METHODS

ARPE-19 cells were treated with varying concentrations of ferrous ammonium citrate (FAC) and salidroside. In an in vivo model, C57BL/6 mice were administered intraperitoneal injections of salidroside for 7 consecutive days, followed by an intravitreal injection (IVT) of FAC. After 7 days, the eyeballs were harvested for subsequent analyses. Ferroptosis markers were assessed using western blotting, immunofluorescence staining, and flow cytometry. To further elucidate the modulatory role of Nrf2 in ferroptosis, ARPE-19 cells were transfected with si-Nrf2.

RESULTS

In vitro, FAC-treated ARPE-19 cells exhibited reduced viability, decreased mitochondrial membrane potential (MMP), and accumulation of iron and lipid peroxidation (LOS) products. In vivo, FAC administration by IVT led to outer nuclear layer thinning and compromised tight junctions in RPE cells. The GPX4, Nrf2, and SLC7A11 expressions were downregulated both in vitro and in vivo. Salidroside upregulated Nrf2 and ameliorated these outcomes, but its effects were attenuated in ARPE-19 cells transfected with si-Nrf2.

CONCLUSION

Our study establishes that FAC induces RPE cell ferroptosis within dry AMD, and salidroside exerts therapeutic effects by triggering Nrf2/SLC7A11/GPX4 signaling axis.

Postnatal weight gain and retinopathy of prematurity in preterm infants: a population-based retrospective cohort study

OBJECTIVE

Infants who meet the screening guidelines for retinopathy of prematurity (ROP) based on birth weight and gestational age undergo serial ophthalmological examinations for its detection and treatment. However, <10% of patients require treatment, and less than half develop ROP. Poor postnatal weight gain has been reported to be a strong indicator of ROP development; however, the information regarding this is unclear. Therefore, this study aimed to determine the relationship between postnatal weight gain and ROP development in preterm infants.

METHODS

The data of 675 preterm infants with gestational age ≤32 weeks, who were hospitalized in our neonatal intensive care unit, were obtained retrospectively from file records. The infants' demographic characteristics, clinical findings, and weekly weight gain (g/kg/day) during the first 8 weeks were recorded. The univariate was used to examine the risk factors for ROP followed by multivariate regression.

RESULTS

The incidence of ROP in the infants included in the study was 41% (n = 278) and 13.3% (n = 37) of them required treatment. In the infants of the group that developed ROP, the mean birth weight and gestational age were significantly lower than those in the group that did not develop ROP (973 ± 288 and 1301 ± 349 g, p = 0.001 and 28.48 ± 1.95 and 30.08 ± 1.60 weeks, p = 0.001, respectively). As the gestational week and birth weight decreased, ROP development and the risk of ROP-requiring treatment increased. In the infants of the group that developed ROP, the mean weight gain in the postnatal third week was detected as significantly lower compared to those in the group that did not develop ROP (13.9 ± 8.2 and 15.4 ± 6.8 g, p = 0.034). On multiple logistic regression analysis, birth weight (<750 g) (odds ratio [OR], 8.67; 95% confidence interval [CI], 3.99-18.82, p = 0.001), blood transfusion (OR, 2.39; 95% CI, 1.34-4.24, p = 0.003), necrotizing enterocolitis (OR, 4.79; 95% CI, 1.05-26.85, p = 0.045), bronchopulmonary dysplasia (OR, 2.03; 95% CI, 1.22-3.36, p = 0.006), antenatal steroid therapy (OR, 1.60; 95% CI, 1.05-2.43, p = 0.028), surfactant administration (OR, 2.06; 95% CI, 1.32-3.2, p = 0.001) were independent risk factors for ROP development.

CONCLUSION

Postnatal weight gain may not be an accurate predictor of ROP development after adjusting for confounding factors. However, the analysis of independent risk factors that influenced the development of ROP revealed a statistically significant effect in cases of low birth weight, blood transfusion, necrotizing enterocolitis, bronchopulmonary dysplasia, and antenatal steroid and surfactant therapies. These findings may help ophthalmologists and neonatologists to pay special attention to this patient group during ROP scanning.

A GUCY2D variant associated cone-rod dystrophy with electronegative ERG: A case report and review

Purpose

Cone-rod dystrophies (CORD) are inherited retinal dystrophies characterized by primary cone degeneration with secondary rod involvement. We report two patients from the same family with a dominant variant in the guanylate cyclase 2D (GUCY2D) gene with different phenotypes in the electroretinogram (ERG).

Observations

A 21-year-old lady (Patient 1) was referred due to experiencing blurry vision and color vision impairment. Visual field testing revealed a central scotoma. Spectral-domain optical coherence tomography (SD-OCT) and fundus autofluorescence (FAF) documented macula dysfunction. Reduced amplitude was observed in the photopic responses of ERG. Her 54-year-old father (Patient 2) had similar issues with blurry vision. A dilated fundus examination displayed bilateral macular atrophy. Loss of the ellipsoid zone line and collapse of the outer nuclear segment were noted on the SD-OCT. Photopic ERG responses were extinguished, and an electronegative ERG was observed in the dark-adapted 3.0 ERG. The gene report revealed a c.2512C > T (p.Arg838Cys) variant in GUCY2D for both patients. They were respectively diagnosed as cone dystrophy (COD) and cone-rod dystrophy (CORD).

Conclusions

We report two different clinical phenotypes in GUCY2D-associated COD despite sharing the same variant. A dysfunction in the synaptic junction between the photoreceptor and the secondary neuron was proposed to explain the electronegative ERG. This explanation might extend to other gene-related cases of CORD with electronegative ERG.

A comprehensive long-term follow-up study of Brown-McLean syndrome

Purpose

This report aims to document a long-term follow-up of a rare case of Brown-McLean syndrome where high-density central corneal endothelial cells (CECs) were maintained, yet the peripheral area developed corneal edema.

Observations

A 72-year-old Japanese male was referred to our hospital. He had a history of three instances of rhegmatogenous retinal detachment in the right eye, requiring three intraocular surgeries. While the circumferential corneal peripheral regions, predominantly in the nasal and temporal areas, exhibited corneal edema, the central region remained clear. The central corneal thickness was measured at 541 μm, and the thickness in the nasal and temporal regions exceeded 700 μm. CEC density at the center was determined to be 2499 cells/mm2 using a non-contact specular microscope, but imaging of the nasal and temporal cornea was obscure due to corneal edema. Panoramic images of the corneal endothelial layer, captured via slit-scanning wide-field contact specular microscopy, showed a high-density and uniform distribution of cells across the clear corneal region, close to the border between edematous and non-edematous areas. Twelve years after the initial visit, the central cornea maintained its transparency and a CEC density of 2456 cells/mm2. Despite the entire peripheral corneal edema, there was no noted deterioration from twelve years prior. The annual reduction in central cornea CECs was a mere 0.09 %.

Conclusions and importance

This case implies the unintended formation of a biological barrier at the border or a possible lack of CEC affinity of centrifugal movement, among other unidentified factors. Such factors may hinder the migration of CECs from the central to the peripheral regions of the cornea, a discovery that is crucial for advancing our knowledge of corneal endothelial biology and exploring new treatment options.

Implementing mobile eye tracking in psychological research: A practical guide

Eye tracking provides direct, temporally and spatially sensitive measures of eye gaze. It can capture visual attention patterns from infancy through adulthood. However, commonly used screen-based eye tracking (SET) paradigms are limited in their depiction of how individuals process information as they interact with the environment in "real life". Mobile eye tracking (MET) records participant-perspective gaze in the context of active behavior. Recent technological developments in MET hardware enable researchers to capture egocentric vision as early as infancy and across the lifespan. However, challenges remain in MET data collection, processing, and analysis. The present paper aims to provide an introduction and practical guide to starting researchers in the field to facilitate the use of MET in psychological research with a wide range of age groups. First, we provide a general introduction to MET. Next, we briefly review MET studies in adults and children that provide new insights into attention and its roles in cognitive and socioemotional functioning. We then discuss technical issues relating to MET data collection and provide guidelines for data quality inspection, gaze annotations, data visualization, and statistical analyses. Lastly, we conclude by discussing the future directions of MET implementation. Open-source programs for MET data quality inspection, data visualization, and analysis are shared publicly.

Demographic Characteristics, Clinical Presentations, and Risk Factors Impacting Visual Outcomes in Peripheral Ulcerative Keratitis

PURPOSE

To assess the demographic characteristics, ophthalmic and systemic presentations, and risk factors impacting the outcomes in patients diagnosed with peripheral ulcerative keratitis (PUK).

METHODS

This retrospective study includes patients diagnosed with PUK at a tertiary care center over 13 years. A descriptive analysis of the demographics, clinical history, and presentation was performed. A reverse risk analysis was performed to assess the PUK resolution in patients with underlying autoimmune and non-autoimmune etiologies. Finally, we evaluated the correlation between treatment duration and final best corrected visual acuity (BCVA) and continuous and categorical variables.

RESULTS

A total of 58 eyes of 51 patients with a mean age of 59.67 ± 13.41 years diagnosed with PUK were included in the study; 58.82% were female. The resolution duration was significantly shorter in patients with autoimmune etiologies (vs. non-autoimmune etiologies, P = 0.028) and female patients (vs. male patients, P = 0.008). The BCVA worsened in patients with non-autoimmune etiologies after treatment ( P = 0.17). Despite worse BCVA at presentation in patients with underlying autoimmune etiologies, significantly better final vision outcomes were observed ( P = 0.04). Linear regression analysis showed that longer treatment duration ( P = 0.001; R 2 = 0.1704) and worse vision ( P = 0.002; R 2 = 0.1502) at presentation were the primary risk factors of poor vision outcomes. Similarly, the treatment duration was significantly longer in male compared with female patients ( P < 0.001; R 2 = 0.2027).

CONCLUSIONS

The clinical outcomes in PUK with underlying autoimmune disorders were observed to be better than non-autoimmune etiologies, which may be attributed to the early detection of the PUK-related changes and aggressive medical management. A delayed diagnosis of PUK leads to poor vision outcomes.

Plasma monomeric ApoA1 and high-density lipoprotein bound ApoA1 are markedly decreased and associated with low levels of lipophilic antioxidants in sickle cell disease: A potential new pathway for therapy

Patients with sickle cell disease (SCD) exhibit high levels of reactive oxygen species and low plasma levels of lipophilic antioxidants, which may contribute to end-organ damage and disease sequelae. Apolipoprotein A1, the major apolipoprotein of high-density lipoprotein (HDL), is mainly secreted by the intestine and liver in the form of monomeric ApoA1 (mApoA1) present in plasma. Cholesterol and α-tocopherol are delivered to ApoA1 via the ATP-binding cassette transporter, subfamily A, member 1 (ABCA1). We measured cholesterol, mApoA1, ApoA1, and lipophilic antioxidants in the plasma of 17 patients with SCD and 40 healthy volunteers. Mean HDL cholesterol (-C) levels in SCD patients and healthy subjects were 59.3 and 48.1 mg/dL, respectively, and plasma lutein, zeaxanthin, and α-tocopherol were 64.0%, 68.7%, and 9.1% lower, respectively. To compare SCD to healthy subjects with similar HDL-C, we also performed subgroup analyses of healthy subjects with HDL-C above or below the mean. In SCD, the mApoA1 level was 30.4 μg/mL; 80% lower than 141 μg/mL measured in healthy volunteers with similar HDL-C (56.7 mg/dL). The mApoA1 level was also 38.4% greater in the higher versus lower HDL-C subgroups (p = .002). In the higher HDL-C subgroup, lutein and zeaxanthin transported by HDL were 48.9% (p = .01) and 41.9% (p = .02) higher, respectively, whereas α-tocopherol was 31.7% higher (p = .003), compared to the lower HDL-C subgroup. Plasma mApoA1 may be a marker of the capacity of HDL to capture and deliver liposoluble antioxidants, and treatments which raise HDL may benefit patients with high oxidative stress as exemplified by SCD.

Exploring and identifying the imaging biomarkers for predicting anti-VEGF treatment response in polypoidal choroidal vasculopathy: a prospective multicenter study

BACKGROUND

Polypoidal choroidal vasculopathy (PCV) is a hemorrhagic fundus disease that can lead to permanent vision loss. Predicting the treatment response to anti-VEGF monotherapy in PCV is consistently challenging. We aimed to conduct a prospective multicenter study to explore and identify the imaging biomarkers for predicting the anti-VEGF treatment response in PCV patients, establish predictive model, and undergo multicenter validation.

METHODS

This prospective multicenter study utilized clinical characteristics and images of treatment naïve PCV patients from 15 ophthalmic centers nationwide to screen biomarkers, develop model, and validate its performance. Patients from Peking Union Medical College Hospital were randomly divided into a training set and an internal validation set. A nomogram was established by univariate, LASSO regression, and multivariate regression analysis. Patients from the other 14 centers served as an external test set. Area under the curve (AUC), sensitivity, specificity, and accuracy were calculated. Decision curve analysis (DCA) and clinical impact curve (CIC) were utilized to evaluate the practical utility in clinical decision-making.

FINDINGS

The eye distribution for the training set, internal validation set, and external test set were 66, 31, and 71, respectively. The 'Good responder' exhibited a thinner subfoveal choroidal thickness (SFCT) (230.67 ± 61.96 vs. 314.42 ± 88.00 μm, p < 0.001), lower choroidal vascularity index (CVI) (0.31 ± 0.08 vs. 0.36 ± 0.05, p = 0.006), fewer choroidal vascular hyperpermeability (CVH) (31.0 vs. 62.2%, p = 0.012), and more intraretinal fluid (IRF) (58.6 vs. 29.7%, p = 0.018). SFCT (OR 0.990; 95% CI 0.981-0.999; p = 0.033) and CVI (OR 0.844; 95% CI 0.732-0.971; p = 0.018) were ultimately included as the optimal predictive biomarkers and presented in the form of a nomogram. The model demonstrated AUC of 0.837 (95% CI 0.738-0.936), 0.891 (95% CI 0.765-1.000), and 0.901 (95% CI 0.824-0.978) for predicting 'Good responder' in the training set, internal validation set, and external test set, respectively, with excellent sensitivity, specificity, and practical utility.

INTERPRETATION

Thinner SFCT and lower CVI can serve as imaging biomarkers for predicting good treatment response to anti-VEGF monotherapy in PCV patients. The nomogram based on these biomarkers exhibited satisfactory performances.

Bioprinting of anisotropic functional corneal stroma using mechanically robust multi-material bioink based on decellularized cornea matrix

Corneal scarring is a common cause of blindness, affecting millions globally each year. A huge gap between the demand and supply of donor tissue currently limits corneal transplantation, the only definitive therapy for patients with corneal scarring. To overcome this challenge, researchers have harnessed the efficacy of 3D bioprinting to fabricate artificial corneal stromal constructs. With all the different bioinks available, the decellularized corneal matrix-based bioprinted construct can fulfill the required biological functionality but is limited by the lack of mechanical stiffness. Additionally, from a biophysical standpoint, it is necessary for an ideal corneal substitute to mimic the anisotropy of the cornea from the central optic zone to the surrounding periphery. In this study, we enhanced the mechanical robustness of decellularized cornea matrix (DCM) hydrogel by blending it with another natural polymer, sonicated silk fibroin solution in a defined ratio. Although hybrid hydrogel has an increased complex modulus than DCM hydrogel, it has a lower in vitro degradation rate and increased opaqueness due to the presence of crystalline beta-sheet conformation within the hydrogel. Therefore, we used this multi-material bioink-based approach to fabricate a corneal stromal equivalent where the outer peripheral corneal rim was printed with a mechanically robust polymeric blend of DCM and sonicated silk fibroin and the central optic zone was printed with only DCM. The bioprinted corneal stroma thus maintained its structural integrity and did not break when lifted with forceps. The two different bioinks were encapsulated with human limbus-derived mesenchymal stem cells (hLMSC) individually and 3D bioprinted in different patterns (concentric and parallel) to attain a native-like structure in terms of architecture and transparency. Thus, the bilayer cornea constructs maintained high cell viability and expressed keratocyte core proteins indicating optimal functionality. This approach helped to gain insight into bioprinting corneas with heterogeneous mechanical property without disturbing the structural clarity of the central optic zone.

SCINet: A Segmentation and Classification Interaction CNN Method for Arteriosclerotic Retinopathy Grading

As a common disease, cardiovascular and cerebrovascular diseases pose a great harm threat to human wellness. Even using advanced and comprehensive treatment methods, there is still a high mortality rate. Arteriosclerosis, as an important factor reflecting the severity of cardiovascular and cerebrovascular diseases, is imperative to detect the arteriosclerotic retinopathy. However, the detection of arteriosclerosis retinopathy requires expensive and time-consuming manual evaluation, while end-to-end deep learning detection methods also need interpretable design to high light task-related features. Considering the importance of automatic arteriosclerotic retinopathy grading, we propose a segmentation and classification interaction network (SCINet). We propose a segmentation and classification interaction architecture for grading arteriosclerotic retinopathy. After IterNet is used to segment retinal vessel from original fundus images, the backbone feature extractor roughly extracts features from the segmented and original fundus arteriosclerosis images and further enhances them through the vessel aware module. The last classifier module generates fundus arteriosclerosis grading results. Specifically, the vessel aware module is designed to highlight the important areal vessel features segmented from original images by attention mechanism, thereby achieving information interaction. The attention mechanism selectively learns the vessel features of segmentation region information under the proposed interactive architecture, which leads to reweighting the extracted features and enhances significant feature information. Extensive experiments have confirmed the effect of our model. SCINet has the best performance on the task of arteriosclerotic retinopathy grading. Additionally, the CNN method is scalable to similar tasks by incorporating segmented images as auxiliary information.

Ocular mucoadhesive and biodegradable spanlastics loaded cationic spongy insert for enhancing and sustaining the anti-inflammatory effect of prednisolone Na phosphate; Preparation, I-optimal optimization, and In-vivo evaluation

This study aimed to formulate and statistically optimize spanlastics loaded spongy insert (SPLs-SI) of prednisolone Na phosphate (PRED) to enhance and sustain its anti-inflammatory effect in a controlled manner. An I-optimal optimization was employed using Design-Expert® software. The formulation variables were sonication time, the Span 60: EA ratio and type of edge activator (Tween 80 or PVA) while Entrapment efficiency (EE%), Vesicles' size (VS) and Zeta potential (ZP) were set as the dependent responses. This resulted in an optimum spanlastics (SPLs) formulation with a desirability of 0.919. It had a Span60:Tween80 ratio of 6:1 with a sonication time of 9.5 min. It was evaluated in terms of its EE%, VS, ZP, release behavior in comparison to drug solution in addition to the effect of aging on its characteristics. It had EE% of 87.56, VS of 152.2 nm and ZP of -37.38 Mv. It showed sustained release behavior of PRED in comparison to drug solution with good stability for thirty days. TEM images of the optimized PRED SPLs formulation showed spherical non-aggregated nanovesicles. Then it was loaded into chitosan spongy insert and evaluated in terms of its visual appearance, pH and mucoadhesion properties. It showed good mucoadhesive properties and pH in the safe ocular region. The FTIR, DSC and XRD spectra showed that PRED was successfully entrapped inside the SPLs vesicles. It was then exposed to an in-vivo studies where it was capable of enhancing the anti-inflammatory effect of PRED in a sustained manner with once daily application compared to commercial PRED solution. The spongy insert has the potential to be a promising carrier for the ocular delivery of PRED.

Prediction of molecular subclasses of uveal melanoma by deep learning using routine haematoxylin-eosin-stained tissue slides

AIMS

Uveal melanoma has a high propensity to metastasize. Prognosis is associated with specific driver mutations and copy number variations, and these can only be obtained after genetic testing. In this study we evaluated the efficacy of patient outcome prediction using deep learning on haematoxylin and eosin (HE)-stained primary uveal melanoma slides in comparison to molecular testing.

METHODS

In this retrospective study of patients with uveal melanoma, 113 patients from the Erasmus Medical Centre who underwent enucleation had tumour tissue analysed for molecular classification between 1993 and 2020. Routine HE-stained slides were scanned to obtain whole-slide images (WSI). After annotation of regions of interest, tiles of 1024 × 1024 pixels were extracted at a magnification of 40×. An ablation study to select the best-performing deep-learning model was carried out using three state-of-the-art deep-learning models (EfficientNet, Vision Transformer, and Swin Transformer).

RESULTS

Deep-learning models were subjected to a training cohort (n = 40), followed by a validation cohort (n = 20), and finally underwent a test cohort (n = 48). A k-fold cross-validation (k = 3) of validation and test cohorts (n = 113 of three classes: BAP1, SF3B1, EIF1AX) demonstrated Swin Transformer as the best-performing deep-learning model to predict molecular subclasses based on HE stains. The model achieved an accuracy of 0.83 ± 0.09 on the validation cohort and 0.75 ± 0.04 on the test cohort. Within the subclasses, this model correctly predicted 70% BAP1-mutated, 61% SF3B1-mutated and 80% EIF1AX-mutated UM in the test set.

CONCLUSIONS

This study showcases the potential of the deep-learning methodology for predicting molecular subclasses in a multiclass manner using HE-stained WSI. This development holds promise for advanced prognostication of UM patients without the need of molecular or immunohistochemical testing. Additionally, this study suggests there are distinct histopathological features per subclass; mainly utilizing epithelioid cellular morphology for BAP1-classification, but an unknown feature distinguishes EIF1AX and SF3B1.

Longitudinal SS-OCT choroidal imaging following thrombosis of the superior ophthalmic vein

Purpose

To report longitudinal changes in choroidal thickness and the choroidal vasculature using SS-OCT imaging in a patient with superior ophthalmic vein thrombosis (SOVT).

Observations

In a 93-year-old woman with a left-sided SOVT, the choroid in the left eye was thickened and the choroidal vessels were dilated both superiorly and inferiorly, with greater changes evident in the inferotemporal region of the choroid. After the superior ophthalmic vein was decompressed, a decrease in the choroidal thickness and choroidal vessel dilatation was observed both superiorly and inferiorly.

Conclusions and importance

In an eye with thrombosis of the superior ophthalmic vein, longitudinal SS-OCT choroidal imaging showed a greater increase in choroidal thickness and choroidal vessel dilation away from the obstructed quadrant, which improved after treatment. These observations associated with outflow obstruction may be applicable to other choroidal diseases characterized by venous overload.

The use of artificial intelligence to assess diabetic eye disease among the Greenlandic population

Background: Retina fundus images conducted in Greenland are telemedically assessed for diabetic retinopathy by ophthalmological nurses in Denmark. Applying an AI grading solution, in a Greenlandic setting, could potentially improve the efficiency and cost-effectiveness of DR screening.Method: We developed an AI model using retina fundus photos, performed on persons registered with diabetes in Greenland and Denmark, using Optos® ultra wide-field scanning laser ophthalmoscope, graded according to ICDR.Using the ResNet50 network we compared the model's ability to distinguish between different images of ICDR severity levels in a confusion matrix.Results: Comparing images with ICDR level 0 to images of ICDR level 4 resulted in an accuracy of 0.9655, AUC of 0.9905, sensitivity and specificity of 96.6%.Comparing ICDR levels 0,1,2 with ICDR levels 3,4, we achieved a performance with an accuracy of 0.8077, an AUC of 0.8728, a sensitivity of 84.6% and a specificity of 78.8%. For the other comparisons, we achieved a modest performance.Conclusion: We developed an AI model using Greenlandic data, to automatically detect DR on Optos retina fundus images. The sensitivity and specificity were too low for our model to be applied directly in a clinical setting, thus optimising the model should be prioritised.

A Causal Inference Approach to Mediation Analysis in Vitreomacular Traction: How Much Does Traction Resolution Mediate Functional Outcomes?

Modern mediation analysis techniques supplement the primary intention-to-treat analysis with the aim to shed light onto the treatment mechanism. We investigate to what extent the anatomic marker vitreomacular adhesion resolution (VMAR) mediates vision benefits, comparing ocriplasmin vs. a sham regimen. A causal mediation analysis is applied to randomized trial data including 218 participants with vitreomacular traction. Logistic regression models are used to estimate the total treatment effect (TTE) on binary outcomes. Outcomes, assessed at month 24, included visual acuity improvement (VA-I): ≥2-line increase in VA; visual function questionnaire improvement (VFQ-I): ≥5-point increase in the 25-item visual function questionnaire composite score (VFQ-25cs); visual function improvement (VF-I): defined as either a VA-I or a clinically meaningful improvement in the VFQ-25cs. Quantity of interest is the breakdown of TTE into an indirect (through VMAR) and direct effect to estimate the extent to which the TTE is transmitted through the mediating variable (VMAR) vs. other pathways. Causal effects are expressed as risk differences. Indirect effects for VFQ-I, VA-I, and VF-I are 5.7%, 11.8%, and 5.2%, respectively, representing the increase in the probability of a vision improvement if VMAR status were changed for each participant to the extent that it is affected by ocriplasmin. The direct effects are 8.3%, 12.1%, and 24.1% respectively, capturing the effect of treatment on the probability of a vision improvement if ocriplasmin left each participant's VMAR status unchanged. The relative treatment effect of ocriplasmin on the functional outcome VA-I is to a large extent the result of its effect on VMAR, while an improvement in the patient-reported outcomes VFQ-I or VF-I was only partially mediated by VMAR.

An insight into the placental growth factor (PlGf)/angii axis in Covid-19: a detrimental intersection

Coronavirus disease 2019 (Covid-19) is a recent and current infectious pandemic caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Covid-19 may lead to the development of acute lung injury (ALI), acute respiratory distress syndrome (ARDS), and extrapulmonary manifestations in severe cases. Down-regulation of angiotensin-converting enzyme (ACE2) by the SARS-CoV-2 increases the production of angiotensin II (AngII), which increases the release of pro-inflammatory cytokines and placental growth factor (PlGF). PlGF is a critical molecule involved in vasculogenesis and angiogenesis. PlGF is stimulated by AngII in different inflammatory diseases through a variety of signaling pathways. PlGF and AngII are interacted in SARS-CoV-2 infection resulting in the production of pro-inflammatory cytokines and the development of Covid-19 complications. Both AngII and PlGF are interacted and are involved in the progression of inflammatory disorders; therefore, we aimed in this review to highlight the potential role of the PlGF/AngII axis in Covid-19.

Melanin in the Retinal Epithelium and Magnetic Sensing: A Review of Current Studies

Coming in a variety of forms, melanin is one of the most abundant, stable, diverse, and evolutionarily ancient pigments found in living things in nature. These pigments often serve protective functions, typically well-adapted to their specific roles. One such protective function is metal chelation and cation exchange, which help regulate and buffer metal concentrations within cells. By binding to certain metals, melanin can acquire magnetic properties. Because of this, it may play a role in magnetic effects and possibly in the response of organisms to external magnetic fields and magnetic sensing. While there is melanin in plants, microbes, fungi, and invertebrates, certain types of melanin are specifically associated with the retina in vertebrates, including migrating bird and fish species. In this review, we examine studies focusing on the properties of melanin in these parts of the body and their possible association with magnetic sensing, and generally, magnetic sensing in the retina.

Trehalose: Neuroprotective Effects and Mechanisms-An Updated Review

Trehalose is a naturally occurring disaccharide that has recently gained significant attention for its neuroprotective properties in various models of neurodegeneration. This review provides an overview of available experimental data on the beneficial properties of trehalose for central nervous system pathological conditions. Trehalose's impact on neuronal cell survival and function was also examined. As a result, we identified that trehalose's neuroprotection includes autophagy modulation as well as its capability to stabilize proteins and inhibit the formation of misfolded ones. Moreover, trehalose mitigates oxidative stress-induced neuronal damage by stabilizing cellular membranes and modulating mitochondrial function. Furthermore, trehalose attenuates excitotoxicity-induced neuroinflammation by suppressing pro-inflammatory cytokine release and inhibiting inflammasome activation. A possible connection of trehalose with the gut-brain axis was also examined. These findings highlight the potential therapeutic effects of trehalose in neurodegenerative diseases. According to the conclusions drawn from this study, trehalose is a promising neuroprotective agent as a result of its distinct mechanism of action, which makes this compound a candidate for further research and the development of therapeutic strategies to combat neuronal damage and promote neuroprotection in various neurological diseases.

Neuronal and glial cell alterations involved in the retinal degeneration of the familial dysautonomia optic neuropathy

Familial dysautonomia (FD) is a rare genetic neurodevelopmental and neurodegenerative disorder. In addition to the autonomic and peripheral sensory neuropathies that challenge patient survival, one of the most debilitating symptoms affecting patients' quality of life is progressive blindness resulting from the steady loss of retinal ganglion cells (RGCs). Within the FD community, there is a concerted effort to develop treatments to prevent the loss of RGCs. However, the mechanisms underlying the death of RGCs are not well understood. To study the mechanisms underlying RGC death, Pax6-cre;Elp1loxp/loxp male and female mice and postmortem retinal tissue from an FD patient were used to explore the neuronal and non-neuronal cellular pathology associated with the FD optic neuropathy. Neurons, astrocytes, microglia, Müller glia, and endothelial cells were investigated using a combination of histological analyses. We identified a novel disruption of cellular homeostasis and gliosis in the FD retina. Beginning shortly after birth and progressing with age, the FD retina is marked by astrogliosis and perturbations in microglia, which coincide with vascular remodeling. These changes begin before the onset of RGC death, suggesting alterations in the retinal neurovascular unit may contribute to and exacerbate RGC death. We reveal for the first time that the FD retina pathology includes reactive gliosis, increased microglial recruitment to the ganglion cell layer (GCL), disruptions in the deep and superficial vascular plexuses, and alterations in signaling pathways. These studies implicate the neurovascular unit as a disease-modifying target for therapeutic interventions in FD.

Endothelial Unfolded Protein Response-Mediated Cytoskeletal Effects

The endothelial semipermeable monolayers ensure tissue homeostasis, are subjected to a plethora of stimuli, and their function depends on cytoskeletal integrity and remodeling. The permeability of those membranes can fluctuate to maintain organ homeostasis. In cases of severe injury, inflammation or disease, barrier hyperpermeability can cause irreparable damage of endothelium-dependent issues, and eventually death. Elucidation of the signaling regulating cytoskeletal structure and barrier integrity promotes the development of targeted pharmacotherapies towards disorders related to the impaired endothelium (e.g., acute respiratory distress syndrome, sepsis). Recent reports investigate the role of unfolded protein response in barrier function. Herein we review the cytoskeletal components, the unfolded protein response function; and their interrelations on health and disorder. Moreover, we emphasize on unfolded protein response modulators, since they ameliorate illness related to endothelial leak.

Branch retinal artery occlusion from laser pointer misuse

Purpose

To report a case of branch retinal artery occlusion (BRAO) following exposure to a blue laser pointer in a healthy 22-year-old male.

Observations

A 22-year-old healthy male presented with sudden visual field impairment in his right eye, occurring 18 hours after exposure to a blue laser pointer. He complained of an immediate persistent curtain-like obstruction in the upper visual field of the affected eye. Clinical examinations revealed BRAO in the inferior half of the retina, confirmed by Optical coherence tomography (OCT) showing edema. Fluorescein angiography indicated delayed filling and a focal hyperfluorescence area, consistent with a leak. Due to a lack of established management, the patient was offered follow-up care. Though reperfusion was observed on fluorescein angiography one month later, thinning of the retinal layers was evident on OCT, and there was no visual recovery.

Conclusions and Importance

In conclusion, laser pointers, though often considered innocuous, can lead to serious ocular damage. The clinical implications of laser-induced retinal injury are severe and sometimes irreversible, warranting special attention. The observed clinical course underscores the complex nature of such injuries and emphasizes the importance of awareness and caution regarding laser pointer use.

Periocular granulomatous inflammatory lesions mimicking conjunctival melanoma recurrence in the setting of systemic nivolumab treatment

Purpose

Conjunctival melanoma is a rare neoplasm with high rates of recurrence and metastasis. Traditional management includes surgical excision and cryotherapy, followed by adjuvant therapy as needed. Immune checkpoint inhibitors, including nivolumab, are a targeted treatment option with improved survival rates. However, various immune-related adverse effects have been reported with these drugs. While systemic granulomatous inflammation is a documented systemic side effect, it has rarely been reported in the conjunctiva and ocular adnexa.

Observation

A patient with a history of recurrent metastatic conjunctival melanoma presented with both a left sub-conjunctival and upper eyelid lesion after the commencement of treatment with nivolumab. The lesions were excised with a clinical suspicion for metastasis and consisted of noncaseating granulomatous inflammation with no evidence of malignancy on histopathologic examination. Infectious and primary autoimmune etiologies were ruled out.

Conclusion and importance

This is a biopsy-proven case of periocular immune checkpoint inhibitor-associated granulomatous inflammation.

Improvement in signs and symptoms of severe dry eye disease after dual therapy with high-potency steroids and 0.05% cyclosporine

OBJECTIVE

To evaluate the effectiveness and safety of combining 0.05% cyclosporine A (CsA) with high-potency steroids for treating severe dry eye disease (DED).

MATERIALS AND METHODS

This retrospective comparative case series included 93 patients treated with 0.05% CsA for severe DED. Among them, we included data from 54 eyes of 27 patients who received high-potency steroids in the study group and from 132 eyes of 66 patients who did not receive high-potency steroids in the control group. Data on demographic characteristics, comorbidities, medications and intraocular pressure (IOP) were recorded. The primary outcomes were changes in symptom and sign scores. The ocular surface disease index was used as the symptom score, whereas tear break-up time, Schirmer I test without anaesthesia, ocular surface staining scores and presence of meibomian gland dysfunction were considered as sign scores. Repeated one-way ANOVA and generalized linear mixed models were used to evaluate differences.

RESULTS

In the control group, symptom scores decreased from 1 to 2 months and from 2 to 3 months after treatment (p = .002 and .049). In the high-potency steroid group, symptom scores improved during these intervals (p = .003 and .005). The sign score in the control group remained unchanged (all p > .05), while the high-potency steroid group exhibited progressive improvement in sign scores (all p < .05). The high-potency steroid group had more favourable symptom (p = .035) and sign (p < .001) scores than did the control group. However, multiple systemic diseases were associated with poor symptom (p = .025) and sign (p = .014) scores. The risks for glaucoma and cataract formation were similar between the two groups (all p > .05).

CONCLUSIONS

Dual therapy combining high-potency steroids and 0.05% CsA significantly improved the signs and symptoms of severe DED compared with 0.05% CsA monotherapy, without severe complications.

MUC1‑ND interacts with TRPV1 to promote corneal epithelial cell proliferation in diabetic dry eye mice by partly activating the AKT signaling pathway

Although both mucin1 (MUC1) and transient receptor potential cation channel subfamily V member 1 (TRPV1) have been reported to be associated with dry eye (DE) disease, whether they interact and their regulatory roles in diabetic DE disease are unknown. Diabetic DE model mice were generated by streptozotocin induction and assessed by corneal fluorescein staining, tear ferning (TF) tests, phenol red thread tests, hematoxylin and eosin staining of corneal sections and periodic acid Schiff staining of conjunctival sections. Cell proliferation was measured by CCK8 assay. Western blotting was performed to measure protein expression. Primary mouse corneal epithelial cells (MCECs) were cultured after enzymatic digestion. Immunofluorescence staining of MCECs and frozen corneal sections was conducted to assess protein expression and colocalization. Coimmunoprecipitation was performed to detect protein‑protein interactions. It was found that, compared with control mice, diabetic DE mice exhibited increased corneal epithelial defects, reduced tear production, poorer TF pattern grades and impaired corneal and conjunctival tissues. In vivo and in vitro experiments showed that hyperglycemia impaired cell proliferation, accompanied by decreased levels of the MUC1 extracellular domain (MUC1‑ND) and TRPV1. Additionally, it was found that capsazepine (a TRPV1 antagonist) inhibited the proliferation of MCECs. Notably, MUC1‑ND was shown to interact with the TRPV1 protein in the control group but not in the diabetic DE group. It was also found that the AKT signaling pathway was attenuated in the diabetic DE mice and downstream of TRPV1. MUC1‑ND interacted with TRPV1, partly activating the AKT signaling pathway to promote MCEC proliferation. The present study found that the interaction of MUC1‑ND with TRPV1 promotes MCEC proliferation by partly activating the AKT signaling pathway, providing new insight into the pathogenesis of corneal epithelial dysfunction in diabetic DE disease.

Implementation of deep learning artificial intelligence in vision-threatening disease screenings for an underserved community during COVID-19

INTRODUCTION

Age-related macular degeneration, diabetic retinopathy, and glaucoma are vision-threatening diseases that are leading causes of vision loss. Many studies have validated deep learning artificial intelligence for image-based diagnosis of vision-threatening diseases. Our study prospectively investigated deep learning artificial intelligence applications in student-run non-mydriatic screenings for an underserved, primarily Hispanic community during COVID-19.

METHODS

Five supervised student-run community screenings were held in West New York, New Jersey. Participants underwent non-mydriatic 45-degree retinal imaging by medical students. Images were uploaded to a cloud-based deep learning artificial intelligence for vision-threatening disease referral. An on-site tele-ophthalmology grader and remote clinical ophthalmologist graded images, with adjudication by a senior ophthalmologist to establish the gold standard diagnosis, which was used to assess the performance of deep learning artificial intelligence.

RESULTS

A total of 385 eyes from 195 screening participants were included (mean age 52.43  ±  14.5 years, 40.0% female). A total of 48 participants were referred for at least one vision-threatening disease. Deep learning artificial intelligence marked 150/385 (38.9%) eyes as ungradable, compared to 10/385 (2.6%) ungradable as per the human gold standard (p < 0.001). Deep learning artificial intelligence had 63.2% sensitivity, 94.5% specificity, 32.0% positive predictive value, and 98.4% negative predictive value in vision-threatening disease referrals. Deep learning artificial intelligence successfully referred all 4 eyes with multiple vision-threatening diseases. Deep learning artificial intelligence graded images (35.6  ±  13.3 s) faster than the tele-ophthalmology grader (129  ±  41.0) and clinical ophthalmologist (68  ±  21.9, p < 0.001).

DISCUSSION

Deep learning artificial intelligence can increase the efficiency and accessibility of vision-threatening disease screenings, particularly in underserved communities. Deep learning artificial intelligence should be adaptable to different environments. Consideration should be given to how deep learning artificial intelligence can best be utilized in a real-world application, whether in computer-aided or autonomous diagnosis.

A possible origin of the inverted vertebrate retina revealed by physical modeling

The evolutionary origin of the inverted retina in the vertebrate eye is unknown. This paper explores a hypothetical evolutionary scenario that explains the unique orientation of the photoreceptors in the vertebrate retina. The proposed scenario follows the scientific accepted scenario for eye evolution and gradually builds up towards an eye prototype by considering light direction detection and increase in achievable spatial resolution as the driving forces. It suggests that eye retinas developed along two different morphological processes, an evagination process that results in the inverted retina in vertebrate eyes and an invagination process that results in a verted retina in cephalopod eyes. The development of the inverted vertebrate retina and eye prototype morphology is strongly substantiated by physics of vision. The proposed evolutionary sequence for vertebrate eye development is simple and has the full potential to explain the origin of the inverted retina and leads to an eye prototype enabling visual detection and orientation. It allows the emergence of eye structures like, extraocular muscles, tapetum lucidum, biconvex lens, cornea, and pupil. This study supports the suggestion that a primitive inverted retina in the predecessor of vertebrates is of ectodermal origin and available before neurulation occurred.

A dataset of color fundus images for the detection and classification of eye diseases

The retina is a critical component of the eye responsible for capturing visual information, making the importance of retinal health for clear vision. Various eye diseases, such as age-related macular degeneration, diabetic retinopathy, and glaucoma, can severely impair vision and even lead to blindness if not detected and treated early. Therefore, automated systems using machine learning and computer vision techniques have shown promise in the early detection and management of these diseases, reducing the risk of vision loss. In this context, to facilitate the development and evaluation of machine learning models for eye disease detection, we introduced a comprehensive dataset which was collected during a span of eight months from Anawara Hamida Eye Hospital & B.N.S.B. Zahurul Haque Eye Hospital using Color Fundus Photography machine. The dataset has two categories of data: color fundus photographs and anterior segment images. The color fundus photographs categorized into nine classes: Diabetic Retinopathy, Glaucoma, Macular Scar, Optic Disc Edema, Central Serous Chorioretinopathy (CSCR), Retinal Detachment, Retinitis Pigmentosa, Myopia, Healthy and anterior segment images has one class: Pterygium. This dataset comprises 5335 primary images. By providing a rich and diverse collection of color fundus photographs, this dataset serves as a valuable resource for researchers and clinicians in the field of ophthalmology for the automatic detection of nine different classes of eye diseases.

Macular telangiectasia type 2 in a patient with Down syndrome: A possible association

Purpose

Down syndrome (DS) is one of the most prevalent genetic diseases associated with a variety of ophthalmic disorders, including reported retinal abnormalities. Macular telangiectasia type 2 (MacTel 2) is a late-onset neurodegenerative retinal disease with a substantial genetic component. We hereby describe a case of a female with DS who presented with MacTel 2, and we discuss the possible pathways associating both entities.

Observation

We report the case of a 49-year-old female with a medical history of DS and hydroxychloroquine (HCQ) intake. She was referred for HCQ retinal toxicity screening. The multimodal imaging revealed a temporal perifoveal gray area with crystal deposits on multicolor fundoscopy with parafoveal outer retinal atrophy and ellipsoid zone loss with inner retinal cavitations in both eyes on the optical Coherence Tomography (OCT) B scan. The corresponding swept-source OCT angiography confirmed the presence of bilateral macular telangiectasia.

Conclusion and importance

Metabolic pathways including serine/glycine and sphingolipids are incriminated in both entities' pathogenesis suggesting a possible association, hence, the importance of raising awareness of this association. More cases are likely to be found since DS patients currently have a nearly normal lifespan. Additional retinal examination of DS adults is then necessary to look for signs of MacTel 2.

Decreased sialylation elicits complement-related microglia response and bipolar cell loss in the mouse retina

Sialylation plays an important role in self-recognition, as well as keeping the complement and innate immune systems in check. It is unclear whether the reduced sialylation seen during aging and in mice heterozygous for the null mutant of UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (Gne+/-), an essential enzyme for sialic acid biosynthesis, contributes to retinal inflammation and degeneration. We found a reduction of polysialic acid and trisialic acid expression in several retinal layers in Gne+/- mice at 9 months of age compared to Gne+/+ wildtype (WT) mice, which was associated with a higher microglial expression of the lysosomal marker CD68. Furthermore, the total number of rod bipolar cells was reduced in 12 months old Gne+/- mice in comparison to WT mice, demonstrating loss of these retinal interneurons. Transcriptome analysis showed up-regulation of complement, inflammation, and apoptosis-related pathways in the retinas of Gne+/- mice. Particularly, increased gene transcript levels of the complement factors C3 and C4 and the pro-inflammatory cytokine Il-1β were observed by semi-quantitative real-time polymerase chain reaction (sqRT-PCR) in 9 months old Gne+/- mice compared to WT mice. The increased expression of CD68, loss of rod bipolar cells, and increased gene transcription of complement factor C4, were all prevented after crossing Gne+/- mice with complement factor C3-deficient animals. In conclusion, our data show that retinal hyposialylation in 9 and 12 months old Gne+/- mice was associated with complement-related inflammation and lysosomal microglia response, as well as rod bipolar cells loss, which was absent after genetic deletion of complement factor C3.

Advances in the study of tissue-engineered retinal pigment epithelial cell sheets

Regarded as the most promising treatment modality for retinal degenerative diseases, retinal pigment epithelium cell replacement therapy holds significant potential. Common retinal degenerative diseases, including Age-related Macular Degeneration, are frequently characterized by damage to the unit comprising photoreceptors, retinal pigment epithelium, and Bruch's membrane. The selection of appropriate tissue engineering materials, in conjunction with retinal pigment epithelial cells, for graft preparation, can offer an effective treatment for retinal degenerative diseases. This article presents an overview of the research conducted on retinal pigment epithelial cell tissue engineering, outlining the challenges and future prospects.

Emerging role and the signaling pathways of uncoupling protein 2 in kidney diseases

OBJECTIVES

Uncoupling protein 2 (UCP2) was involved in the pathogenesis and development of kidney diseases. Many signaling pathways and factors regulate the expression of UCP2. We aimed to investigate the precise role of UCP2 and its signaling pathways in kidney diseases.

METHODS

We summarized the available evidence to yield a more detailed conclusion of the signal transduction pathways of UCP2 and its role in the development and progression of kidney diseases.

RESULTS

UCP2 could interact with 14.3.3 family proteins, mitochondrial phospholipase iPLA2γ, NMDAR, glucokinase, PPARγ2. There existed a signaling pathway between UCP2 and NMDAR, PPARγ. UCP2 can inhibit the ROS production, inflammatory response, and apoptosis, which may protect against renal injury, particularly AKI. Meanwhile UCP2 can decrease ATP production and inhibit the secretion of insulin, which may alleviate chronic renal damages, such as diabetic nephropathy and kidney fibrosis.

CONCLUSIONS

Homeostasis of UCP2 is helpful for kidney health. UCP2 may play different roles in different kinds of renal injury.

The clinical and genetic spectrum of mitochondrial diseases in China: A multicenter retrospective cross-sectional study

Mitochondrial diseases (MtDs) present diverse clinical phenotypes, yet large-scale studies are hindered by their rarity. This retrospective, multicenter study, conducted across five Chinese hospitals' neurology departments from 2009 to 2019, aimed to address this gap. Nationwide, 1351 patients were enrolled, with a median onset age of 14.0 (18.5) years. The predominant phenotype was mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) (45.0%). Mitochondrial DNA (mtDNA) mutations were prevalent (87.4%), with m.3243A>G being the most common locus (48.7%). Meanwhile, POLG mutations in nuclear DNA (nDNA) accounted for 16.5%. Comparative analysis based on age groups (with a cut-off at 14 years) revealed the highest prevalence of MELAS, with Leigh syndrome (LS) and chronic progressive external ophthalmoplegia (CPEO) being the second most common phenotypes in junior and senior groups, respectively. Notably, the most commonly mutated nuclear genes varied across age groups. In conclusion, MELAS predominated in this Chinese MtD cohort, underscored by m.3243A>G and POLG as principal mtDNA mutations and pathogenic nuclear genes. The phenotypic and genotypic disparities observed among different age cohorts highlight the complex nature of MtDs.

Targeted Neonatal Echocardiography: Basics of Knobology 101

Targeted neonatal echocardiography (TNE) is essential when approaching hemodynamic instability in neonates. Competency in this field requires standardized training, including robust hands-on experience. Proficiency in understanding the key elements of ultrasound knobology is indispensable for optimal acquisition of imaging. This is a narrative review summarizing the key elements of knobology in TNE. Literature review was mainly done through PubMed. There was no funding allocated for the production of this manuscript. KEY POINTS: · Robust and structured training is essential. · Understanding knobology is required to achieve competency in TNE. · Optimizing knobology is critical for an accurate hemodynamic interpretation report.

Vessel-promoted OCT to OCTA image translation by heuristic contextual constraints

Optical Coherence Tomography Angiography (OCTA) is a crucial tool in the clinical screening of retinal diseases, allowing for accurate 3D imaging of blood vessels through non-invasive scanning. However, the hardware-based approach for acquiring OCTA images presents challenges due to the need for specialized sensors and expensive devices. In this paper, we introduce a novel method called TransPro, which can translate the readily available 3D Optical Coherence Tomography (OCT) images into 3D OCTA images without requiring any additional hardware modifications. Our TransPro method is primarily driven by two novel ideas that have been overlooked by prior work. The first idea is derived from a critical observation that the OCTA projection map is generated by averaging pixel values from its corresponding B-scans along the Z-axis. Hence, we introduce a hybrid architecture incorporating a 3D adversarial generative network and a novel Heuristic Contextual Guidance (HCG) module, which effectively maintains the consistency of the generated OCTA images between 3D volumes and projection maps. The second idea is to improve the vessel quality in the translated OCTA projection maps. As a result, we propose a novel Vessel Promoted Guidance (VPG) module to enhance the attention of network on retinal vessels. Experimental results on two datasets demonstrate that our TransPro outperforms state-of-the-art approaches, with relative improvements around 11.4% in MAE, 2.7% in PSNR, 2% in SSIM, 40% in VDE, and 9.1% in VDC compared to the baseline method. The code is available at: https://github.com/ustlsh/TransPro.

Hyperglycemia-induced oxidative stress exacerbates mitochondrial apoptosis damage to cochlear stria vascularis pericytes via the ROS-mediated Bcl-2/CytC/AIF pathway

OBJECTIVES

Diabetes is closely linked to hearing loss, yet the exact mechanisms remain unclear. Cochlear stria vascularis and pericytes (PCs) are crucial for hearing. This study investigates whether high glucose induces apoptosis in the cochlear stria vascularis and pericytes via elevated ROS levels due to oxidative stress, impacting hearing loss.

METHODS

We established a type II diabetes model in C57BL/6J mice and used auditory brainstem response (ABR), Evans blue staining, HE staining, immunohistochemistry, and immunofluorescence to observe changes in hearing, blood-labyrinth barrier (BLB) permeability, stria vascularis morphology, and apoptosis protein expression. Primary cultured stria vascularis pericytes were subjected to high glucose, and apoptosis levels were assessed using flow cytometry, Annexin V-FITC, Hoechst 33342 staining, Western blot, Mitosox, and JC-1 probes.

RESULTS

Diabetic mice showed decreased hearing thresholds, reduced stria vascularis density, increased oxidative stress, cell apoptosis, and decreased antioxidant levels. High glucose exposure increased apoptosis and ROS content in pericytes, while mitochondrial membrane potential decreased, with AIF and cytochrome C (CytC) released from mitochondria to the cytoplasm. Adding oxidative scavengers reduced AIF and CytC release, decreasing pericyte apoptosis.

DISCUSSION

Hyperglycemia may induce mitochondrial apoptosis of cochlear stria vascularis pericytes through oxidative stress.

M2 macrophages promote subconjunctival fibrosis through YAP/TAZ signalling

PURPOSE

To evaluate the role of M2 macrophages in subconjunctival fibrosis after silicone implantation (SI) and investigate the underlying mechanisms.

MATERIALS AND METHODS

A model of subconjunctival fibrosis was established by SI surgery in rabbit eyes. M2 distribution and collagen deposition were evaluated by histopathology. The effects of M2 cells on the migration (using wound-scratch assay) and activation (by immunofluorescence and western blotting) of human Tenon's fibroblasts (HTFs) were investigated.

RESULTS

There were more M2 macrophages (CD68+/CD206+ cells) occurring in tissue samples around silicone implant at 2 weeks postoperatively. Dense collagen deposition was observed at 8 weeks after SI. In vitro experiment showed M2 expressed high level of CD206 and transforming growth factor-β1 (TGF-β1). The M2-conditioned medium promoted HTFs migration and the synthesis of collagen I and fibronectin. Meanwhile, M2-conditioned medium increased the protein levels of TGF-β1, TGF-βR II, p-Smad2/3, yes-associated protein (YAP), and transcriptional coactivator with PDZ-binding motif (TAZ). Verteporfin, a YAP inhibitor, suppressedTGF-β1/Smad2/3-YAP/TAZ pathway and attenuated M2-induced extracellular matrix deposition by HTFs.

CONCLUSIONS

TGF-β1/Smad2/3-YAP/TAZ signalling may be involved in M2-induced fibrotic activities in HTFs. M2 plays a key role in promoting subconjunctival fibrosis and can serve as an attractive target for anti-fibrotic therapeutics.

Minocycline-induced retinal pigment epithelium hyperpigmentation masquerading as age-related macular degeneration: Case presentation and proposed mechanism

Purpose

We describe the case of an 80-year-old man with bilateral minocycline-induced retinal pigment epithelium (RPE) hyperpigmentation, which initially masqueraded as AMD. Secondarily, using multimodal imaging features, we propose a mechanism for the development of minocycline-induced RPE hyperpigmentation.

Observations

The patient was referred with concern for AMD given the presence of macular drusenoid deposits on optical coherence tomography. However, funduscopic evaluation showed dense granular parafoveal hyperpigmentation, with a diffuse slate-colored hyperpigmentation throughout the peripheral fundus. Short-wavelength fundus autofluorescence of the macula disclosed no irregularities (as would be expected with drusen) while on near-infrared reflectance (NIR) imaging, numerous hyperreflective foci were noted corresponding to the hyperpigmented granules observed clinically (as would instead be seen with melanin deposits). Clinical examination was notable for blue-gray hyperpigmentation of the lower and upper extremities, as well as of the face, periorbital skin, and sclera. Upon further questioning, the patient disclosed daily oral minocycline use for 15 years for acne rosacea, confirming a diagnosis of minocycline-induced hyperpigmentation of the RPE.

Conclusions

Multimodal imaging can be useful for differentiating minocycline-induced RPE hyperpigmentation from similar masquerade entities. Timely diagnosis can prevent progressive vision loss.

An unusual pAIR: Anti-PKM2 antibody and occult pancreatic adenocarcinoma

Purpose

To describe the clinical, laboratory and multimodal imaging findings in paraneoplastic autoimmune retinopathy (p-AIR) associated with anti-pyruvate kinase M2 antibody (anti-PKM2) and occult pancreatic adenocarcinoma.

Observations

A 70 year old male with blurred vision, nyctalopia and concurrent difficulty with glucose control had retinal vascular attenuation and diffuse punctate pigment clumping in both eyes. Multimodal imaging demonstrated corresponding stippled hypofluorescence on fluorescein angiography, stippled hyperautofluorescence and a hyperautoflourescent macular ring with fundus autofluorescence, and focal hyperreflectivity at the level of the RPE-Bruch's membrane complex with diffuse loss of outer retinal layers on ocular coherence tomography. In addition, diffuse ganglion cell loss and severe visual field constriction were present. Genetic testing for retinitis pigmentosa was normal. Screening for anti-retinal antibodies was positive for only anti-PKM2. Systemic evaluation revealed previously undiagnosed adenocarcinoma of the pancreas.

Conclusions and importance

Anti-PKM2 in the setting of autoimmune retinopathy may be associated with occult pancreatic cancer. The diagnosis of pAIR should be considered and systemic investigation for occult malignancy initiated even in the absence of more commonly associated anti-retinal antibodies.

Ultra-processed foods consumption and risk of age-related eye diseases: a prospective cohort study with UK biobank

PURPOSE

Consumption of ultra-processed foods (UPF) has been associated with increased risks of various age-related diseases. However, the potential association between UPF consumption and age-related eye diseases (AREDs) remains unclear. We aim to assess the associations between consumption of UPF and risk of AREDs including age-related macular degeneration (AMD), cataract and glaucoma.

METHODS

We included 156,232 individuals aged 50 or older, who were free from AREDs from UK biobank study. Dietary intake data were collected using 24-h dietary assessments. UPF is defined according to the NOVA classification, and all participants are divided into four quartiles based on the weight proportion (%) of UPF. During a median of 10 years of follow-up. Cox proportional hazards were used to estimate the association between the proportion of UPF in the diet and the subsequent risk of various AREDs.

RESULTS

After adjusting for multiple variables, individuals in the highest quartiles for UPF consumption exhibited an increased risk of AMD (hazard ratio (HR): 1.28; 95% confidence interval (CI): 1.01-1.63; p = 0.03), cataract (HR: 1.10; 95% CI: 1.01-1.20; p = 0.04), and glaucoma (HR: 1.27; 95% CI: 0.98-1.63; p = 0.06) compared to those in the lowest quartiles. Moreover, a 10% increase in the weight of UPF in diet was associated with an 8% higher risk of AMD (HR: 1.08; 95% CI: 1.01-1.15; p = 0.03), a 3% higher risk of cataract (HR: 1.03; 95% CI: 1.00-1.06; p = 0.04), and a 7% higher risk of glaucoma (HR: 1.07; 95% CI: 1.00-1.15; p = 0.05).

CONCLUSION

Our results suggest that a higher proportion of UPF in the diet was significantly link with an elevated risk of AMD and cataract. While additional research is necessary to validate these findings in diverse populations and settings, these results offer initial evidence to endorse public health initiatives that encourage limiting consumption of UPF.

Activation of retinoid X receptors protects retinal neurons and pigment epithelial cells from BMAA-induced death

Exposure to the non-protein amino acid cyanotoxin β-N-methylamino-L-alanine (BMAA), released by cyanobacteria found in many water reservoirs has been associated with neurodegenerative diseases. We previously demonstrated that BMAA induced cell death in both retina photoreceptors (PHRs) and amacrine neurons by triggering different molecular pathways, as activation of NMDA receptors and formation of carbamate-adducts was only observed in amacrine cell death. We established that activation of Retinoid X Receptors (RXR) protects retinal cells, including retina pigment epithelial (RPE) cells from oxidative stress-induced apoptosis. We now investigated the mechanisms underlying BMAA toxicity in these cells and those involved in RXR protection. BMAA addition to rat retinal neurons during early development in vitro increased reactive oxygen species (ROS) generation and polyADP ribose polymers (PAR) formation, while pre-treatment with serine (Ser) before BMAA addition decreased PHR death. Notably, RXR activation with the HX630 agonist prevented BMAA-induced death in both neuronal types, reducing ROS generation, preserving mitochondrial potential, and decreasing TUNEL-positive cells and PAR formation. This suggests that BMAA promoted PHR death by substituting Ser in polypeptide chains and by inducing polyADP ribose polymerase activation. BMAA induced cell death in ARPE-19 cells, a human epithelial cell line; RXR activation prevented this death, decreasing ROS generation and caspase 3/7 activity. These findings suggest that RXR activation prevents BMAA harmful effects on retinal neurons and RPE cells, supporting this activation as a broad-spectrum strategy for treating retina degenerations.

Biomaterial engineering strategies for modeling the Bruch's membrane in age-related macular degeneration

Age-related macular degeneration, a multifactorial inflammatory degenerative retinal disease, ranks as the leading cause of blindness in the elderly. Strikingly, there is a scarcity of curative therapies, especially for the atrophic advanced form of age-related macular degeneration, likely due to the lack of models able to fully recapitulate the native structure of the outer blood retinal barrier, the prime target tissue of age-related macular degeneration. Standard in vitro systems rely on 2D monocultures unable to adequately reproduce the structure and function of the outer blood retinal barrier, integrated by the dynamic interaction of the retinal pigment epithelium, the Bruch's membrane, and the underlying choriocapillaris. The Bruch's membrane provides structural and mechanical support and regulates the molecular trafficking in the outer blood retinal barrier, and therefore adequate Bruch's membrane-mimics are key for the development of physiologically relevant models of the outer blood retinal barrier. In the last years, advances in the field of biomaterial engineering have provided novel approaches to mimic the Bruch's membrane from a variety of materials. This review provides a discussion of the integrated properties and function of outer blood retinal barrier components in healthy and age-related macular degeneration status to understand the requirements to adequately fabricate Bruch's membrane biomimetic systems. Then, we discuss novel materials and techniques to fabricate Bruch's membrane-like scaffolds for age-related macular degeneration in vitro modeling, discussing their advantages and challenges with a special focus on the potential of Bruch's membrane-like mimics based on decellularized tissue.

Altered fatty acid distribution in lysosome-associated membrane protein-2 deficient mice

Lysosome-associated membrane protein-2 (LAMP2) deficiency causes the human Danon disease and represents a lysosomal dysfunction because of its pivotal role in regulating autophagy and lysosome biogenesis. LAMP2-deficient mice exhibit a spectrum of phenotypes, including cardioskeletal myopathy, mental retardation, and retinopathy, similar to those observed in patients with Danon disease. Its pathology is thought to involve altered energy metabolism and lipid dysregulation; however, the lipidomic profiles of LAMP2-deficient animals have not been investigated. In this study, we investigated lipid alterations in LAMP2 KO mice tissues, including those of the liver, plasma, and retina, using liquid chromatography-mass spectrometry. Our results revealed significantly increased free fatty acid (FFA) levels and decreased in triglyceride (TG) levels in LAMP2 KO liver tissues at three and six months. Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) species significantly decreased in LAMP2 KO mice livers at six months. Similarly, plasma TG and PC/PE levels decreased in LAMP2 KO mice. In contrast, plasma FFA levels were significantly lower in LAMP2 KO mice. Retina FFA levels were elevated in LAMP2 KO mice, accompanied by a partial decrease in PC/PE at six months. In summary, FFA levels increased in several tissues but not in the LAMP2 KO mice plasma, suggesting the potential consumption of FFA as an energy source in the peripheral tissues. The depletion of TG and PC/PE accelerated with age, suggesting an underlying age-dependent energy crisis condition. Our findings underscore the dysregulated distribution of fatty acids in LAMP2-deficient animals and provide new mechanistic insights into the pathology of Danon disease.

Development of a novel SupraChoroidal-to-Optic-NervE (SCONE) drug delivery system

PURPOSE

Targeted drug delivery to the optic nerve head may be useful in the preclinical study and later clinical management of optic neuropathies, however, there are no FDA-approved drug delivery systems to achieve this. The purpose of this work was to develop an optic nerve head drug delivery technique.

METHODS

Different strategies to approach the optic nerve head were investigated, including standard intravitreal and retroorbital injections. A novel SupraChoroidal-to-Optic-NervE (SCONE) delivery was optimized by creating a sclerotomy and introducing a catheter into the suprachoroidal space. Under direct visualization, the catheter was guided to the optic nerve head. India ink was injected. The suprachoroidal approach was performed in New Zealand White rabbit eyes in vivo (25 animals total). Parameters, including microneedle size and design, catheter design, and catheter tip angle, were optimized ex vivo and in vivo.

RESULTS

Out of the candidate optic nerve head approaches, intravitreal, retroorbital, and suprachoroidal approaches were able to localize India ink to within 2 mm of the optic nerve. The suprachoroidal approach was further investigated, and after optimization, was able to deposit India ink directly within the optic nerve head in up to 80% of attempts. In eyes with successful SCONE delivery, latency and amplitude of visual evoked potentials was not different than the naïve untreated eye.

CONCLUSIONS

SCONE delivery can be used for targeted drug delivery to the optic nerve head of rabbits without measurable toxicity measured anatomically or functionally. Successful development of this system may yield novel opportunities to study optic nerve head-specific drug delivery in animal models, and paradigm-shifting management strategies for treating optic neuropathies.

TRANSLATIONAL RELEVANCE

Here we demonstrate data on a new method for targeted delivery to the optic nerve head, addressing a significant unmet need in therapeutics for optic neuropathies.

Causal relationship between 731 immune cells and the risk of diabetic nephropathy: a two‑sample bidirectional Mendelian randomization study

OBJECTIVE

Previous observational studies have indicated associations between various immune cells and diabetic nephropathy (DN). However, the causality remains unclear. We aimed to further evaluate the causal association between immune cells and DN using bidirectional two-sample Mendelian randomization (MR) analysis.

METHOD

The DN data were retrieved from the IEU OpenGWAS Project database, while the data for 731 immune cells were sourced from GWAS summary statistics by Orru ̀ et al. The investigation into the causal relationship between immune cells and DN employed the inverse variance weighted (IVW), weighted median (WME), and MR-Egger methods. The stability and reliability of the findings underwent evaluation through Cochran's Q test, MR-Egger intercept's P-value, MR-PRESSO, and Leave-One-Out (LOO) method.

RESULT

The IVW estimates suggested a positive causal effect of CD25 on IgD-CD38dim B cell, CD25 on naive-mature B cell, CD127 on granulocyte, SSC-A on HLA DR + Natural Killer, HLA DR on plasmacytoid Dendritic Cell, and HLA DR on Dendritic Cell on DN. Conversely, the abundance of Myeloid Dendritic Cell, CD62L- Dendritic Cell %Dendritic Cell, CD86+ myeloid Dendritic Cell %Dendritic Cell, CD14- CD16-, CX3CR1 on CD14- CD16-, and SSC-A on CD4+ T cell had negative causal effects on DN. However, after correcting the P value for significant causality results using the FDR method, it was concluded that only Myeloid Dendritic Cells had a causal relationship with DN (FDR-p = 0.041), while the other immune cells showed no significant association with DN, so their relationship was suggestive. The results were stable with no observed horizontal pleiotropy and heterogeneity. Reverse MR analysis indicated no causal relationship between DN and the increased risk of positively identified immune cells.

CONCLUSION

This study provides an initial insight into the genetic perspective of the causal relationship between immune cells and DN. It establishes a crucial theoretical foundation for future endeavors in precision medicine and individualized treatment.

The relationship between contact lens ultraviolet light transmittance and myopia progression: a large-scale retrospective cohort study

Background

The prevalence of myopia is increasing dramatically around the world, and many studies have suggested the possibility that ultraviolet (UV) light is effective to prevent the onset and progression of myopia. However, UV is a risk factor for diseases that cause refractive errors such as cataract and pterygium. In this study, we evaluated the relationship between UV exposure and myopia progression.

Methods

The dataset consisted of a total of 337 396 eyes of patients in the 12-to-29-year age range, who were prescribed soft contact lenses (SCL) for refractive error at Okada Eye Clinic in Japan between 2002 and 2011. They were tracked over a five-year period and did not change the type of SCL. In this retrospective cohort study based on medical records, we divided patients into two groups, one prescribed SCL with UV protection (UV-SCL), and another prescribed SCL without UV protection (UV + SCL).

Results

Change in refractive power over five years was measured and results compared. It was -0.413 diopter (D) in the UV-SCL group and -0.462 D in the UV + SCL group. Thus, the progression of myopia was slower in the UV-SCL group. The results were also analyzed separately by gender and degree of myopia at the time of initial prescription, which all showed significant differences (P < 0.001).

Conclusion

Results suggest that UV exposure may advance myopia. Further research is needed to investigate the underlying mechanisms that could explain this.