Investigative Ophthalmology & Visual Science
● Association for Research in Vision and Ophthalmology (ARVO)
Preprints posted in the last 30 days, ranked by how well they match Investigative Ophthalmology & Visual Science's content profile, based on 25 papers previously published here. The average preprint has a 0.02% match score for this journal, so anything above that is already an above-average fit.
Solebo, A.; Chen, B.; Aznan, N.; Xochiale, M.; Roberts, T.; Petrushkin, H.; Lim, C.; Shu, R.; Jacobson, M.; Farisogullari, I.; Abdelfattah, K.; Tynan, D.; Lotay, J.; Vijjan, K.; Tsika, C.; Williams, O.; Clare, G.; Testi, I.; Tucker, W. R.; Addison, P.; Pavesio, C.; Rahi, J. S.; Taylor, P.; Chu, C. J.
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Objective: To investigate the performance of anterior segment (AS) OCT quantitative imaging of anterior chamber inflammation in uveitis patients with diverse demographics. Design: Prospective cross-sectional study. Participants: 144 adult patients managed at a tertiary care service in the UK Methods: Repeated swept-source ASOCT imaging was performed pre- and post-pupil dilation (i.e. 4 scan sets). Inflammation was quantified using a validated human in the loop automated image analysis pipeline, Minuscule Cell Detection (MCD), which identified and counted putative inflammatory cells on AS-OCT. Main Outcome Measures: Test-retest variability of ASOCT and diagnostic accuracy of various ASOCT derived measurands (minimum, maximum, median counts per cross sectional image, and total counts across volume image sets per eye or MINCC, MAXCC, MEDCC and TOTCC) versus Standardization of Uveitis Nomenclature (SUN) grading system as assessed by a uveitis specialist. Results: A total of 281 eyes were included in the analysis. Median age was 48 years (IQR 36 to 64). Strong test-retest measurand reliability was demonstrated, with a 95% tolerance interval ratio 0.3 to 3.0. The best diagnostic performances for SUN activity were observed with the MINCC threshold of 3 particles (negative predictive value for clinical activity of 89.8%, 95% CI 83.0 to 94.1). Associations between ASOCT measurands and patient age (adjusted coefficient 7.5 additional particles, 95% CI 0.5 to 14.6, p<0.04 for age over 60 years versus under 44), and pigment load (52.8, 11.8 to 92.9, p<0.01 in eyes with AC pigment versus without) were noted. Conclusions: ASOCT assessment of anterior chamber inflammation in uveitis meets current recommendations for quantitative imaging biomarkers, demonstrating strong repeatability, linearity with clinical assessment scores and stability with pupil dilation and patient characteristics of ethnicity and lens status. The absence of variability in diagnostic indices across derived measurands suggests similar performance across different acquisition protocols. Further longitudinal cross-platform studies are needed to determine limitations of use.
Huang, Y.; Zhang, Y.; Zhang, S.; Lissit, K.; Talley-Rostov, A.; Lin, C. C.; Tsai, P. S.; Hong, A.; Agrawal, A.; Thomas, J.; Chang, L.-Y.; Sulewski, M.; Cochella, L.; Xu, J.; Eghrari, A. O.
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Abstract Purpose: To expand the clinical and mechanistic understanding of the +57C>T seed-region mutation in miR-184 causing EDICT (endothelial dystrophy, iris hypoplasia, congenital cataract, and stromal thinning) syndrome. Design: Cross-sectional analysis and laboratory confirmation Participants: 18 members of a four-generation family with known +57C>T miR-184 status Methods: We used optical biometry, corneal topography, and medical history to characterize the clinical phenotype. Carrier effects on ocular biometric measurements were estimated using polygenic linear mixed models incorporating a pedigree-derived kinship matrix, adjusted for age and sex. Patient-derived and control induced pluripotent stem cells (iPSCs) were generated and differentiated into corneal endothelial cells (CECs). Main Outcome Measures: Axial length, keratometry (in diopters), white-to-white corneal diameter, topography mapping, central and peripheral corneal thickness, and history of retinal detachment or corneal transplant were compared between mutation carriers and noncarriers, adjusting for age and sex. Cellular analysis was conducted with immunostaining (ZO-1, ATP1A1), morphometric quantification, qRT-PCR of endothelial markers, and transendothelial electrical resistance (TEER). Results: 10 of 18 family members were heterozygous for +57C>T, with retinal detachment occurring in 5/10 affected individuals compared to 0/8 unaffected individuals (p=0.04). Affected eyes had 2.2 mm shorter axial length (p=0.02), 9.3 D steeper mean keratometry (p=0.004), 1.6 mm smaller horizontal corneal diameter (p=0.0001), and 139-micrometer thinner central corneas (p=0.003). Mutant iPSC-derived CECs were associated with irregular borders, increased cell and nucleus area, widened intercellular gaps, disrupted ATP1A1 membrane localization, and reduced barrier function on TEER (all p<0.05). Gene expression analysis showed downregulation of COL4A1, COL4A3, and AQP1 with upregulation of COL8A1. Conclusions: The miR-184 +57C>T mutation produces a broad ocular phenotype that includes smaller, thinner corneas and microphthalmia. Mechanistically, it disrupts CEC junctional integrity, extracellular matrix and pump-related genes, supporting a role for miR-184 in coordinated anterior-posterior eye morphogenesis.
Laird, J. G.; Soetedjo, J.; Inamdar, S. M.; Bock, A. R.; Ataman, E.; Pufall, M. A.; Berkowitz, B. A.; Baker, S. A.
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Purpose: Photoreceptor Kv2.1/Kv8.2 voltage-gated potassium channels carry an outward potassium current, helping to set the resting membrane potential and to shape dim light responses. Because potassium flux in the outer retina influences extracellular osmolarity and fluid distribution, we hypothesized that Kv2.1/Kv8.2 channels also contribute to fluid homeostasis in this region of the retina. Methods: OCT imaging was performed in Kv8.2 heterozygous (Het) and knockout (KO) mice aged 4-7 weeks under dark- and light-adapted conditions. Light-dark differences in the distance between the external limiting membrane (ELM) and retinal pigment epithelium (RPE) ({Delta}ELM-RPE) were calculated to quantify light-evoked expansion of the subretinal space (SRS). As a secondary outcome, outer nuclear layer (ONL) thickness was also measured under both lighting conditions. Retinal gene expression was assessed by RNA-seq and droplet digital RT-PCR. Retinal protein expression was determined by western blotting and immunolabeling. Results: {Delta}ELM-RPE was significantly reduced in Kv8.2 KO mice compared with Het controls, indicating reduced SRS hydration. ONL thickness exhibited a small but significant light-dark change that was different between genotypes. Transcriptomic analyses revealed upregulation of osmosensitive genes, including osmolyte transporters and aquaporins. AQP1 protein expression in photoreceptors increased. Conclusions: These findings reveal a previously unrecognized role for Kv2.1/Kv8.2 channels in outer retinal fluid homeostasis and support a model in which photoreceptor potassium efflux contributes to osmotic water movement into the subretinal space.
Lim, J.; Larimer-Picciani, A. M.; Moshiri, A.; Wang, J.-K.; Takahashi, N.; Raposo, A. C. S.; Motta, M. J.; Byrne, L.; Thomasy, S. M.
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PurposeOculocutaneous albinism type 1 (OCA1) is an inherited disorder caused by tyrosinase (TYR) gene mutations. Affected individuals experience visual impairment and severe photosensitivity from ocular hypomelanosis, with no current treatments. We evaluated the safety and efficacy of a TYR-encoding adeno-associated virus (AAV) vector in healthy rhesus macaques as a potential OCA1 treatment. MethodsA novel AAV2-based capsid (ATX002) was packaged with the human VMD2 promoter and TYR (hTYR) fused with mGreenLantern (mGL). Two adult rhesus macaques were injected with ATX002-hVMD2-hTYR-mGL subretinally (OD) and intravitreally (OS). Safety and efficacy were assessed via comprehensive ophthalmic examination, fundus photography, spectral-domain optical coherence tomography (SD-OCT), and full-field electroretinography at baseline and defined timepoints up to 12 weeks post-injection, followed by post-mortem immunohistochemistry (IHC). ResultsBoth subretinal doses induced localized hypermelanosis by 3 weeks post-injection, which persisted through the study endpoint and was accompanied by measurable thickening of the retinal pigment epithelium (RPE) on SD-OCT. Histological IHC confirmed successful RPE transduction via robust mGL fluorescence, corroborating in vivo findings by revealing localized RPE hyperplasia and transgene-expressing cells adjacent to regions of de novo hypermelanosis. Intravitreal delivery did not induce any changes to the RPE. Transient uveitis was observed but successfully managed with anti-inflammatory treatment. ConclusionsSubretinal AAV-TYR delivery is a safe and effective approach with the potential to induce RPE pigmentation. These findings support the use of AAV-TYR gene therapy for OCA1, demonstrating efficacy and a manageable safety profile in a large-animal model, and provide a critical bridge toward human clinical translation.
Yang, Y.; Shen, L.; Luna, E. C.; Zhou, L. Y.; Espino, P. C. H.; Li, G.; Chen, L.
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Purpose: Lymphatic system plays a critical role in fluid regulation and immune response. The conjunctiva of the ocular surface is endowed with a rich lymphatic network, and it provides an ideal site to study lymphatic structure and function. The purpose of this study is to investigate potential morphological and functional changes of conjunctival lymphatics with aging, a time-dependent biological deterioration process. Methods: Young and aged fluorescently labeled transgenic mice of Prox-1, the master control gene for lymphatic determination, were used in the study. For morphological assessment, conjunctival lymphatic vessels were examined in vivo by our advanced live imaging system. For functional analysis, lymphatic drainage efficiencies were measured by fluorescently labeled tracer injection. Results: Compared to young mice, both vascular branching points and intraluminal valves were significantly reduced in conjunctival lymphatic vessels of aged mice. Moreover, lymphatic functional deterioration and drainage deficiencies, such as fluid leakage and reflux, were also detected in the aged condition. Conclusions: Conjunctival lymphatic system undergoes morphological as well as functional changes with aging. Further investigation into this phenomenon may provide novel insights into lymphatic and age-related diseases inside and outside the eye.
Handel, K. W.; Lim, J.; Iwashita, H.; Khan, S.; Shevalye, H.; Park, S.; Echeverria, N.; Ferneding, M.; Khan, M. J.; Roszak, K. P.; Donovan, G. L.; Iwamoto, M.; Shim, J.; Young, L. J.; Ardon, M.; Le, S. M.; Leonard, B. C.; Skeie, J. M.; Greiner, M.; Thomasy, S.
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Col8a2Q455K/Q455K (Q455K) mice exhibit features of early-onset Fuchs endothelial corneal dystrophy (FECD), including decreased endothelial cell density (ECD) and guttae formation. Within the context of these clinical features, this study longitudinally evaluates ferroptosis in Q455K and wild-type (WT) mice using in vivo imaging, PCR and immunohistochemistry. Fifty-six Q455K and 56 WT mice were evaluated from 3 to 24 months of age with in vivo confocal microscopy; ECD and guttae were measured. Ferroptosis marker expression was determined with PCR and immunohistochemistry (IHC). Data were analyzed using two-way ANOVA with Tukeys post hoc test, Chi-square test and a paired t-test. The ECD significantly decreased in both groups from 3 to 24 months of age, but more markedly in Q455K (2285-/+317 to 1012-/+58 cells/mmSquare) versus WT mice (2714-/+139 to 2057-/+149 cells/mmSquare, P<0.0001). Guttae were observed exclusively in Q455K mice beginning at 3 months of age and increased over time (P=0.0003). The Q455K mice demonstrate guttae at the vertices of corneal endothelial cells rather than their centers (74.3% vs. 25.7%P<0.001). Expression of ferroptosis-related genes (Tfrc, Slc40a1, Ftl1, Gpx4) were significantly increased in the Q455K versus WT mice (P<0.05). Furthermore, corresponding protein expression (transferrin receptor 1, ferroportin, ferritin and glutathione peroxidase 4) was significantly elevated adjacent to guttae in Q455K versus WT mice (P<0.05). These findings implicate guttae in the initiation of ferroptosis as it relates to the pathophysiology of FECD and provide an optimal window for testing novel FECD therapies using this murine model, particularly those that target ferroptosis.
Rasmussen, D.;Marschall, P.;Lee, S.;Storm, T.;Jakobsen, T.;Wu, Q.;Askou, A.;Fenton, R.;Corydon, T.;Mahajan, V.;Nielsen, R.
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The multiligand endocytic receptor, megalin (LRP2), is expressed in the retinal pigment epithelium (RPE) and patients lacking the receptor develop high myopia. Despite its established role in retinal development, the contribution of megalin to retinal homeostasis in the normally developed/mature eye remains poorly understood. Here, we investigated megalin function using an inducible knockout mouse (KO) model and human iPSC-derived RPE with megalin knockdown (KD) to distinguish post-developmental homeostatic functions from developmental effects. In vivo, megalin ablation caused progressive retinal degeneration and visual impairment, with morphological abnormalities in the RPE but no changes in myopia-associated ocular phenotypes including axial length and intraocular pressure. Proteomic profiling of megalin-KO RPE revealed reduction of autophagy-related proteins. In line with this, megalin deficiency was associated with accumulation of pro-cathepsin D, and perturbed rhodopsin turnover. This was supported in vitro, where trafficking of photoreceptor outer segment (POS) containing phagosomes to lysosomes was reduced, suggesting disturbed phagosome maturation. Megalin KD did not measurably impair initial uptake of POS discs, but delayed rhodopsin degradation, indicating defective post-ingestion processing. Together, these findings establish megalin as a key regulator of retinal homeostasis in the mature eye by controlling phagosome-lysosome fusion in the RPE and suggest that megalin dysfunction contributes to slowly progressive retinal degeneration. This positions megalin as a potential therapeutic target in lysosomal degenerative diseases in the retina.
Bhuckory, M. B.; Mamchick, V.; Monkongpitukkul, N.; Pham-Howard, D.; Shautsova, V.; Vu, L. M.; Galambos, L.; Butt, E.; Mathieson, K.; Kamins, T.; Palanker, D.
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Subretinal photovoltaic implants provide central vision to patients blinded by atrophic age-related macular degeneration, with acuity limited by their 100-{micro}m pixels. Higher resolution requires smaller pixels incorporating three-dimensional electrodes, which can be fabricated by gold electroplating. However, the retinal response to exposed gold remains poorly characterized. Here, we evaluated gold biocompatibility on subretinal implants in Royal College of Surgeons rats and compared it with platinum- and titanium-coated surfaces. Although in-vivo optical coherence tomography revealed no overt structural disruption, gold implants induced cellular-scale anomalies, including abnormal morphology of rod bipolar cells, microglial accumulation near the implant, and increased cell death within days after implantation. These effects occurred across flat, pillar, and honeycomb geometries, indicating a material-rather than geometry-dependent response. By contrast, platinum- and titanium-coated implants showed substantially lower loss and morphological disruption of rod bipolar cells, together with markedly reduced microglial activation. These findings indicate that exposed gold surfaces can induce acute retinal inflammation and neuronal loss, whereas conformal platinum or titanium coatings substantially improve biocompatibility. Such coatings enable the development of three-dimensional subretinal prostheses with smaller pixels for improved visual resolution.
Schaefer, P.; Corna, A.; Kurth, T.; Hain, V.; Schoen, A.; Ferguson, S.; Cojocaru, A.-E.; Rabesandratana, O.; Allan, L.; Decembrini, S.; Arias, J. E. R.; GOUREAU, O.; Santos-Ferreira, T.; Zeck, G.; Ader, M.
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Cell replacement represents a potential treatment modality for retinal disorders characterized by photoreceptor loss. However, photoreceptor replacement approaches have not been clinically established. To take this forward, the main goal of this study was to systematically compare human photoreceptors of different ages and identify those that enable functional integration into the degenerative retina. Donor cells were isolated from iPSC-derived retinal organoids generated by a GMP-compliant protocol at differentiation days 120, 150, or 200 and transplanted subretinally into cone photoreceptor function loss 1 (Cpfl1) recipients, an inherited mouse model of cone degeneration. While younger photoreceptors showed slightly improved transplantation outcomes, donor photoreceptors of all culture stages displayed long-term survival, cone identity, structural integration into the host retina, and tight interactions with host Mueller glia, including formation of a continuous outer limiting membrane. Transplanted photoreceptors showed signs of advanced maturation, including correct polarization with generation of apical inner- and outer segments, while basal synapses were formed with host bipolar cells. Electrophysiological assessment of host retinal ganglion cells revealed light-evoked responses in transplant-containing regions, providing evidence for functional incorporation of human photoreceptors into the mouse neuro-retinal circuitry. Thus, GMP-compliant human iPSC-derived photoreceptors are stable over a wide range of differentiation stages and constitute a robust cell source for retinal transplantation and functional repair. The findings provide important prerequisites for the development of standardized procedures towards clinical translation of photoreceptor replacement in the retina.
Larimer-Picciani, A. M.; Jacob, L. B.; Sullinger, K. J.; Kriebel, W. G.; Sahel, J.-A.; Byrne, L. C.
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Oculocutaneous albinism type 1 (OCA1) is a pigmentation disorder caused by biallelic tyrosinase (TYR) mutations, an essential enzyme for melanin synthesis. TYR inactivity results in loss of hair, skin, and eye pigment, which is detrimental for ocular function. Hypopigmentation of iris, retinal pigment epithelium (RPE), and choroid results in severe photosensitivity and low visual acuity. There are currently no FDA-approved pigment restoring therapies for OCA1, making therapeutic development an unmet clinical need. To address this gap, we have advanced an adeno-associated viral (AAV)-mediated Tyr replacement approach for OCA1 ocular pigment restoration. We evaluated the optimal viral delivery strategy and vector cell-type specificity for iris, RPE, and choroid pigmentation in an OCA1 mouse model, testing intraocular and systemic viral delivery methods in conjunction with viral constructs of varying RPE-specificity. Early, systemic delivery of an RPE-directed AAV-Tyr construct, AAV9.2yf-VMD2-Tyr, achieved widespread ocular pigment rescue with minimal off-target expression in non-ocular tissues. Animals treated with AAV9.2yf-VMD2-Tyr demonstrated reduced photophobic behavior compared to untreated controls, indicating that ocular pigmentation restores a debilitating functional consequence of OCA1. Our findings establish a foundation for clinical translation of an AAV-TYR therapy aimed at improving light sensitivity, glare, and low vision through pigment restoration in patients with OCA1.
Hussain, A.; Tajdaran, K.; Katturajan, R.; Mirmoeini, K.; Crabtree, J.; Quddam, A. I.; Wu, X.; Blum, N.; Konig, D. J.; Pepose, J. S.; Ali, A.; Shalom-Feuerstein, R.; Gordon, T.; Kaplan, D. R.; Borschel, G. H.; Feinberg, K.
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Corneal epithelial integrity depends on continuous epithelial renewal by limbal epithelial stem cells (LESCs), a process tightly linked to sensory innervation. Loss or impairment of innervation causes neurotrophic keratopathy (NK), a sight-threatening degenerative disease for which rhNGF, the only FDA-approved pharmacologic therapy, often has limited efficacy in advanced or refractory disease. The mechanistic basis for this limited response remains unclear. Using surgical, genetic, and pharmacologic approaches in a rodent model of NK with corneal Schwann cell ablation or structural and functional denervation, together with primary human LESCs, we examined how denervation alters NGF receptor signaling during epithelial repair. In innervated corneas, NGF promoted epithelial regeneration through TrkA. Denervation, however, increased expression of a second NGF receptor, anti-regenerative p75NTR, and activation of its effector JNK, and reduced the activity of the TrkA effector AKT in LESCs. In this altered receptor context, denervation-induced elevation of endogenous NGF amplified p75NTR signaling, thereby explaining the failure of topical rhNGF to rescue severely denervated NK phenotype corneas. Conversely, selective TrkA activation, either with the clinical-stage agonist tavilermide, or pharmacologic or genetic inhibition/ablation of p75NTR, restored AKT signaling and rescued epithelial healing in denervated corneas independent of reinnervation. These findings identify a nerve-dependent NGF receptor switch as a key regulator of corneal epithelial renewal and establish receptor-selective modulation as a mechanistically rational therapeutic strategy for treating NK. One Sentence SummaryCorneal denervation shifts limbal epithelial stem cell signaling from pro-regenerative TrkA-AKT toward anti-regenerative p75NTR-JNK, explaining the limited efficacy of recombinant human nerve growth factor (rhNGF; cenegermin), the only approved pharmacologic therapy for neurotrophic keratopathy, in severely denervated corneas and identifying receptor-selective modulation as a mechanistically distinct therapeutic strategy.
Bentley-Ford, M. R.; Palumaa, T.; Lou, L.; Jonnalagadda, A.; Bade, M. L.; Balamurugan, S.; Mazade, R.; Pardue, M. T.
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Purpose: Animal models of myopia typically induce monocular refractive shifts via form deprivation (FD) or lens-induced myopia (LIM), modeling susceptibility to myopia, but with potentially limited applicability to childhood myopia. Here we describe a novel, genetically diverse mouse model of naturally occurring refractive error (NORE) with three distinct refractive phenotypes: hyperopic, myopic, and intermediate. Methods: C57BL/6J mice were mated to 129S2/SvPasCrl mice to create F1 or F2 offspring. Refractive errors in male and female F1 (N=21) and F2 (N=101) mice were assessed on postnatal days (P) 28 and 42 using photorefractometry. In a subset of mice (N=30 - 40), corneal radius of curvature, axial ocular dimensions, retinal and visual function were assessed. Results: F2 mice were classified as NORE with either hyperopic (RE [≥] 0 diopters (D) at P28 and P42), myopic (RE<0D at P28 and P42) or intermediate (RE<0D at P28 and RE [≥] 0D at P42) refractions based on individual trajectories. All ocular parameters changed with age, with significantly slower growth in axial length and vitreous chamber depth in the intermediate versus myopic mice (p<0.05). Lens thickness was smaller in the myopic group at P28. Differences in refraction were not attributed to variances in retinal function or dopamine signaling. Conclusions: NORE mice represent a novel, genetically diverse wild-type mouse model that, unlike traditional models, does not require interventions such as FD or LIM to induce myopia. NORE mice provide a valuable tool for future investigations of genetic and environmental mechanisms and targeted therapeutic strategies for refractive errors.
Sankaranarayanan, R.; Vasavada, A. R.; Agrawal, D.; Vasavada, S. A.; Vasavada, V. A.
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Purpose: To identify transcript-level variants in crystallin genes in paediatric patients with unilateral cataracts. Methods: Anterior capsulorhexis (n=12) from patients underwent surgical management of congenital unilateral cataracts was collected. Total RNA was isolated from lens epithelial cells, and complementary DNA (cDNA) was synthesized. Full-length RNA transcripts of 10 lens-specific crystallin genes were PCR-amplified and analysed via Sanger sequencing. Identified transcript variants were further validated using genomic DNA (gDNA) through Sanger sequencing. In addition, the full-length (~7,535 bp) CRYBA1 genomic region was sequenced using Oxford Nanopore Technology. Results: Aberrant low molecular weight (LMW) amplicons (~370 bp) of the CRYBA1 transcript were identified in three patients presented with unilateral cataract. Of 3 patients, 2 had persistent fetal vasculature (PFV) and 1 had pre-existing posterior capsular defect (PPCD). Sanger sequencing revealed a precise loss of exons 2 to 4 in the CRYBA1 RNA transcript. No coding, splice-site, or large deletion variants were detected in the genomic DNA of the patients or their parents. In silico analysis predicted two possible truncated proteins arising from these alternatively spliced transcripts: one comprising the first 11 amino acids of the N-terminal region with a loss of all Greek key motifs, and another comprising 90 amino acids encoded by exons 5 and 6, initiated from an alternative start codon in exon 5, and loss of Greek key motifs 1 & 2. Conclusion: The precise skipping of exons 2 to 4, consistent with canonical splicing signals (5-prime-GU...AG-3-prime), in the absence of genomic alterations, suggests the presence of alternatively spliced (AS) CRYBA1 transcripts in human lenses. This is the first report documenting AS-CRYBA1 transcripts in association with childhood cataracts with PFV and PPCD.
Adan-Castro, E.; Nunez-Amaro, C. D.; Villareal, J.; H. Islas, I.; Hernandez-Quijano, A.; Rodriguez-Chagoya,, B. E.; Garcia-Roa, M.; Lopez-Star, E.; Garcia-Franco,, R.; Robles-Osorio,, M. L.; Martinez de la Escalera, G.; Clapp, C.
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Background/Objective: Diabetic macular oedema (DMO) is a leading cause for visual impairment primarily managed with intravitreal anti-VEGF agents such as ranibizumab (RBZ). Levosulpiride (LSP), a prokinetic medication, was recently repositioned as a safe oral treatment for naive DMO. Here, we investigated the adjuvant effect of oral LSP in combination with intravitreal RBZ injections for treating persistent DMO. Subjects/Methods: Double-blinded, dual-centre, phase 2 trial in patients with centre-involving DMO randomly assigned to be orally treated with placebo (15 patients, 18 eyes) or LSP (18 patients, 19 eyes) along with 3 successive (4 weeks apart) RBZ intravitreal injections and a 24-week follow-up. Results: Baseline best-corrected visual acuity (BCVA) improved (p[≤]0.04) at week 12 in both RBZ+placebo and RBZ+LSP, but improvement was maintained (p=0.009) at week 24 only in RBZ+LSP. In agreement, longitudinal changes from baseline in BCVA from weeks 12 to 24 defined superior (p=0.02) visual gains measured by the Area Under the Curve (AUC) in RBZ+LSP vs. RBZ+placebo. The baseline value of mean central foveal thickness (CFT) decreased (p[≤]0.002) in both groups at week 12 and CFT reduction was significant (p=0.006) at week 24 only in RBZ+LSP. Also, longitudinal changes from baseline in CFT resulted in a higher AUC reduction (p[≤]0.04) at weeks 4 to12 in RBZ+LSP vs. RBZ+placebo. No significant adverse side effects were detected. Conclusions: Adjunctive LSP showed functional and anatomical benefits over the first-line therapy with RBZ. Adjuvant properties may involve the LSP-induced intraocular upregulation and downregulation of vasoinhibin and VEGF, respectively. Larger clinical trials are warranted.
Volz, S.; Montigel, S. H.; Ryl, T.; Afanasyeva, E.; Haag, D.; Reyes, P.; Mueller, J.; Puranachot, P.; Wedig, T.; Schwarz, N.; Mauermann, M.; Sadeghi Dehcheshmeh, I.; Sill, M.; Autry, R. J.; Sahm, F.; Biewald, E.; Ting, S.; Busch, M.; Jabbarli, L.; Kiefer, T.; Bechrakis, N.; Pfister, S. M.; Pajtler, K. W.; Ketteler, P.; Maass, K. K.
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Primary tumor biopsy in retinoblastoma carries an unacceptable risk of extraocular dissemination. As a result, children treated with eye-sparing approaches currently lack access to tumor-derived genomic information at diagnosis, limiting accurate risk stratification, preventing subtype-guided therapy, and obscuring insight into tumor evolution during conservative treatment. Aqueous humor (AH) liquid biopsy has emerged as a promising window into circulating tumor DNA (ctDNA) from eyes managed conservatively, yet its ability to comprehensively capture the genomic and epigenomic landscape of retinoblastoma and to deliver clinically actionable molecular stratification has not been rigorously evaluated. We analyzed 18 matched AH-tumor pairs using genome-wide methylation profiling, copy-number analysis, and targeted sequencing. AH samples consistently contained high ctDNA fractions (median 0.65), enabling robust detection of single-nucleotide variants, canonical copy-number alterations, and methylation signatures defining established retinoblastoma subtypes. Importantly, promoter methylation patterns associated with RB1 inactivation and optic nerve invasion were confidently detected in AH, highlighting that liquid biopsy enables functional interrogation of disease-relevant genes and pathways. To enable biopsy-independent molecular classification, we developed a methylation-based machine learning classifier trained on combined AH and tumor datasets (n=114). The classifier demonstrated exceptional performance, with AUCs of 0.96-1.00 in cross-validation and 0.97-1.00 in independent validation across 63 additional retinoblastoma cases. Together, these findings position AH liquid biopsy as powerful, minimally invasive platform for comprehensive molecular profiling in retinoblastoma. This work establishes the first clinically viable non-invasive molecular stratification tool for the disease, enabling pretreatment risk assessment and paving the way for next-generation precision diagnostics in eye-preserving care.
Jaurrieta Hinojos, J. N.; Gonzalez Saldivar, G.; Hernandez Vazquez, A. Y.; Saucedo Castillo, A.; Babayan Sosa, A.; Ramirez Estudillo, J. A.
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Purpose: To assess the feasibility of quantitative fundus autofluorescence (FAF) measurement in early age-related macular degeneration (AMD) using the freely available ImageJ software, to characterize signal intensity across FAF patterns, and to evaluate interobserver reproducibility in pattern classification. Methods: Single-center, non-blinded, retrospective, consecutive-case analytical study. FAF images acquired with Spectralis OCT+HRA (Heidelberg Engineering) from patients with early dry AMD seen at a tertiary referral center between January 2010 and September 2016 were analyzed. A standardized 300x300-pixel region of interest (ROI) centered on the fovea was evaluated in ImageJ v2.0.0-rc54/1.51h (Fiji distribution). Mean, minimum, and maximum autofluorescence (AF) pixel intensity were recorded. Each image was independently classified according to the Bindewald classification system by two graders; a third senior grader adjudicated discordances. Cohen's kappa (k) was used to assess interobserver agreement. Results: Of 423 patients with available FAF studies, 107 had dry AMD; 45 met quality and diagnostic criteria for early AMD and were included in the quantitative analysis. Mean age was 73.47 +/- 8.1 years; 62.2% were female. Mean FAF intensity was 120.26 (range 74.76-160.79); mean minimum was 32.07 (range 3-63) and mean maximum was 205.80 (range 125-255). Seven of eight Bindewald patterns were identified; the stippled pattern was absent. The most frequent pattern was minimal changes (31.1%), followed by increased focal (24.4%) and patchy (15.6%). Reticular pattern showed the highest mean AF (143.8), while lace pattern showed the lowest (88.4). Interobserver agreement for Bindewald pattern classification was almost perfect (k = 0.969; 95% CI, 0.908-1.000; p < 0.001). Agreement for lesion extent was moderate (k = 0.531) and for foveal involvement was substantial (k = 0.622). Conclusions: Quantitative FAF evaluation of early AMD using ImageJ is feasible and reproducible. ImageJ represents a cost-free alternative for multimodal retinal image analysis, with potential for automated screening applications in resource-limited settings. Keywords: age-related macular degeneration; fundus autofluorescence; ImageJ; quantitative autofluorescence; image analysis; Bindewald classification; interobserver agreement
Avesani, A.; Dal Cortivo, G.; Asteriti, S.; Targa, G.; Veschetti, L.; Marino, V.; Biasi, A.; Longo, C.; Cisterna, B.; Saran, K.; Malerba, G.; Foik, A. T.; Cambiaghi, M.; Cangiano, L.; Dell'Orco, D.
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Autosomal dominant cone-rod dystrophies (adCORDs) caused by mutations in GUCA1A, encoding the calcium sensor GCAP1 (guanylate cyclase-activating protein 1), lack a disease model combining a clinically severe variant with native expression at the endogenous locus. We addressed this gap by generating and comprehensively characterizing a knock-in mouse carrying p.(E111V), the most biochemically severe GUCA1A variant, uncovering retinal dysfunction that extends beyond phototransduction and reaches central visual pathways. E111V/ mice exhibited rod photoresponse alterations consistent with constitutive guanylate cyclase activation, selective visuospatial behavioral deficits, and progressive decline in visually evoked potentials across visual cortex and superior colliculus, indicating trans-synaptic propagation of delayed photoreceptor kinetics despite milder structural degeneration than in patients. Transcriptomic profiling revealed early Mertk downregulation and progressive synaptic, mitochondrial and inflammatory dysregulation confirmed by electron microscopy. Acute ex vivo delivery of recombinant wild-type GCAP1 partially shifted mutant photoresponses toward wild-type values, supporting feasibility of biochemical modulation via wild-type GCAP1 supplementation.
Guleser, U. Y.; Akkaya, N.; Kesim, C.; Cakmak, O. O.; Karslioglu, M. Z.; Basak, A. N.; Ertan, S.; Hasanreisoglu, M.; Vural, A.
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Purpose: To investigate corneal subbasal nerve plexus alterations using in vivo corneal confocal microscopy (IVCM) in patients with Autosomal Recessive Spastic Ataxia of Charlevoix-Saguenay (ARSACS) and Spastic Paraplegia Type 7 (SPG7). Methods: This cross-sectional pilot study included eight ARSACS patients, five SPG7 patients, and twenty age- and sex-matched healthy controls. All participants underwent neurological and ophthalmological examination followed by central corneal imaging using IVCM. Quantitative corneal nerve parameters were analyzed with automated software, and correlations with clinical severity scales were assessed. Results: The mean age was 34.2 +/- 3.4 years in controls, 34.5 +/- 0.7 years in the ARSACS group, and 38.2 +/- 3.5 years in the SPG7 group. Corneal nerve branch density (CNBD) and corneal nerve total branch density (CTBD) were significantly lower in ARSACS and SPG7 patients compared with healthy controls. CNFD, CNFL, CNFA, CNFW, and CNFrD were lower in ARSACS and SPG7 patients compared with healthy controls; however, these differences did not reach statistical significance. No statistically significant differences in IVCM parameters were detected between ARSACS and SPG7 patients. Spearman correlation analysis did not show significant correlations between corneal nerve parameters and FARS, SARA, ADL scores, or disease duration. Conclusion: IVCM revealed reduced corneal nerve branching parameters in patients with ARSACS and SPG7. These findings indicate involvement of the corneal subbasal nerve plexus and support the potential role of corneal confocal microscopy as a non-invasive ocular imaging modality for evaluating peripheral neural alterations in hereditary spastic ataxias.
Byrne, E. M.; Di Vicino, U.; Farah, N.; Cadevall Angles, M.; Fernandez Merino, M.; Rotkevich, M.; Caravaca Rodriguez, D.; Balashov, M.; Guerra Solano, J. M.; Ibrahim, M. S.; Marin Figuera, J. A.; Puig Galy, J. J.; Sandiumenge, A.; Casaroli Marano, R. P.; Lee, J.; Mandel, Y.; Cosma, M. P.
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Vision loss compromises the quality of life of millions of people worldwide. Currently, vision-restoring therapies are lacking. Post-mortem preservation of human eyes may enable whole eye transplantation (WET) or therapeutic development. We developed an approach to cannulate the ophthalmic artery and perfuse post-mortem pig and human eyes using a custom-built device, Eye-in-Care-Box (ECaBox). Retinal vasculature imaging and reconstruction were used to assess perfusion efficacy using a supervised deep learning model. Without intervention, the retina degrades post-mortem, whereas perfusion preserves retinal structure and cell viability for up to 24-hours. Eyes were perfused within 30 minutes post-extraction, and regained light-responses persisted for up to 10 hours after death, challenging the notion that response to light ends at death. Our findings show that intact eyes can be resuscitated and preserved outside the body, supporting the ECaBox platform for WET preservation and pre-clinical therapeutic testing. Ultimately, ECaBox may bring vision-restoring treatments to patients.
Maxwell, G. E.; Allen, R.; Hodge, L.; Kelley, S.; Craig, J. E.; Cohen-Woods, S.; Souzeau, E.
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Early glaucoma detection and treatment are critical to prevent irreversible blindness. Glaucoma polygenic risk scores (PRS) offer an effective approach for stratifying disease risk and are increasingly available in clinical practice. However, the psychosocial impact of receiving glaucoma PRS results is currently unknown. As such, this study investigated short-term psychosocial outcomes of disclosing glaucoma PRS to individuals over 50 years from the general population. Individuals from the bottom 10%, middle 45 to 55%, and top 10% of PRS scores were invited to receive their results and complete surveys before and 2 weeks after receiving results to assess anxiety, test-related distress, decisional regret, recall and understanding. Of invited participants, 51.7% (136/263) enrolled with 133 completing both surveys. Two weeks after disclosure, PRS recall was high (78.2%), although PRS knowledge remained limited. Privacy concerns were moderate, not differing across PRS groups (X^2 = 4.17, p = .124). Small reductions in glaucoma-related anxiety (z = -2.93, p = .003), generalised anxiety (z = -3.75, p < .001) and stress (z = -2.49, p = .013) were observed following disclosure. While scores remained within normal ranges, higher glaucoma-related anxiety (t = -2.36, p = .020), higher negative emotions (X^2 = 20.80, p < .001), and lower positive experience (F = 5.70, p = .004) were seen for high-risk participants compared to lower-risk participants. Decisional regret was low and did not differ across PRS groups (X^2 = 0.28, p = .869). These findings support the psychosocial safety of glaucoma PRS testing while highlighting the need for improved education and longer-term follow-up to support clinical implementation.