Development of Non-Invasive miRNA Markers for Assessing the Quality of Human Induced Pluripotent Stem Cell-Derived Retinal Organoids.

Human retinal organoids (ROs) have emerged as valuable tools for studying retinal development, modeling human retinal diseases, and screening drugs. However, their application is limited primarily due to time-intensive generation, high costs, and low reproducibility. Quality assessment of RO differentiation is crucial for their application in research. However, traditional methods such as morphological evaluation and immunohistochemical analysis have limitations due to their lack of precision and invasiveness, respectively. This study aims to identify non-invasive biomarkers for RO differentiation quality using exosomal microRNAs (miRNAs), which are known to reflect cell-specific functions and development in the retina. We differentiated ROs from human induced pluripotent stem cells (hiPSCs) and classified them into 'superior' and 'inferior' groups based on morphological and immunohistochemical criteria. Exosomes from the conditioned media were isolated and analyzed for miRNA content. Our findings revealed distinct miRNA profiles between superior and inferior ROs, with superior ROs exhibiting higher miRNA diversity and specifically up- or down-regulated miRNAs. Gene ontology and pathway enrichment analyses indicated that the target genes of these miRNAs are involved in neuron proliferation and differentiation. The study suggests the potential of exosomal hsa-miR-654-3p and hsa-miR-451a as non-invasive biomarkers for real-time monitoring of RO quality, facilitating the development of standardized, efficient, and cost-effective culture methods.

Early Developmental Characteristics and Features of a Three-Dimensional Retinal Organoid Model of X-Linked Juvenile Retinoschisis.

X-linked juvenile retinoschisis (XLRS) is a hereditary retinal degeneration affecting young males caused by mutations in the retinoschisin (RS1) gene. We generated human induced pluripotent stem cells (hiPSCs) from XLRS patients and established three-dimensional retinal organoids (ROs) for disease investigation. This disease model recapitulates the characteristics of XLRS, exhibiting defects in RS1 protein production and photoreceptor cell development. XLRS ROs also revealed dysregulation of Na/K-ATPase due to RS1 deficiency and increased ERK signaling pathway activity. Transcriptomic analyses of XLRS ROs showed decreased expression of retinal cells, particularly photoreceptor cells. Furthermore, relevant recovery of the XLRS phenotype was observed when co-cultured with control ROs derived from healthy subject during the early stages of differentiation. In conclusion, our in vitro XLRS RO model presents a valuable tool for elucidating the pathophysiological mechanisms underlying XLRS, offering insights into disease progression. Additionally, this model serves as a robust platform for the development and optimization of targeted therapeutic strategies, potentially improving treatment outcomes for patients with XLRS.

Intravitreal Administration of Retinal Organoids-Derived Exosomes Alleviates Photoreceptor Degeneration in Royal College of Surgeons Rats by Targeting the Mitogen-Activated Protein Kinase Pathway.

Increasing evidence suggests that exosomes are involved in retinal cell degeneration, including their insufficient release; hence, they have become important indicators of retinopathies. The exosomal microRNA (miRNA), in particular, play important roles in regulating ocular and retinal cell functions, including photoreceptor maturation, maintenance, and visual function. Here, we generated retinal organoids (ROs) from human induced pluripotent stem cells that differentiated in a conditioned medium for 60 days, after which exosomes were extracted from ROs (Exo-ROs). Subsequently, we intravitreally injected the Exo-RO solution into the eyes of the Royal College of Surgeons (RCS) rats. Intravitreal Exo-RO administration reduced photoreceptor apoptosis, prevented outer nuclear layer thinning, and preserved visual function in RCS rats. RNA sequencing and miRNA profiling showed that exosomal miRNAs are mainly involved in the mitogen-activated protein kinase (MAPK) signaling pathway. In addition, the expression of MAPK-related genes and proteins was significantly decreased in the Exo-RO-treated group. These results suggest that Exo-ROs may be a potentially novel strategy for delaying retinal degeneration by targeting the MAPK signaling pathway.

Clinical Manifestations and Genetic Analysis of 5 Korean Choroideremia Patients Initially Diagnosed With Retinitis Pigmentosa.

BACKGROUND: To investigate the clinical findings of choroideremia patients and perform genetic analysis by whole-exome sequencing (WES). METHODS: A total of 94 patients initially diagnosed with retinitis pigmentosa (RP) at another hospital, and who visited our hospital for genetic analysis by WES, were included in the study, along with 64 family members. All subjects underwent comprehensive ophthalmic evaluation, including best-corrected visual acuity, slit lamp examination, fundus photography, fundus autofluorescence (FAF), fluorescein angiography (FAG), visual field (VF), electroretinogram (ERG), and optical coherence tomography (OCT). RESULTS: In six male patients with suspected choroideremia, extensive retinal pigment epithelium (RPE) and severe loss of choroid were observed in the fundus, but not in the macula. CHM gene mutation was confirmed in five patients. A novel single nucleotide variant at a splice site was observed in one patient. OCT showed marked thinning of the outernuclear layer and choroid, except in the macula. FAF showed a small area of hyperfluorescence in the posterior pole. In addition, characteristic interlaminar bridges were observed in four patients. On FAG, hypofluorescence was seen up to the far-peripheral retina in five patients. CONCLUSION: Of the 94 patients initially diagnosed with RP, CHM mutation was identified in five (5.3%) by WES. Choroideremia should be considered as a differential diagnosis of RP. WES would be useful for identifying the causes of hereditary retinal disease.

mTOR-dependent dysregulation of autophagy contributes to the retinal ganglion cell loss in streptozotocin-induced diabetic retinopathy.

BACKGROUND: Neurodegeneration, an early event in the pathogenesis of diabetic retinopathy (DR), precedes clinically detectable microvascular damage. Autophagy dysregulation is considered a potential cause of neuronal cell loss, however underlying mechanisms remain unclear. The mechanistic target of rapamycin (mTOR) integrates diverse environmental signals to coordinate biological processes, including autophagy. Here, we investigated the role of mTOR signaling in neuronal cell death in DR. METHODS: Diabetes was induced by a single intraperitoneal injection of streptozotocin and tissue samples were harvested at 1, 2, 3, 4, and 6 months of diabetes. Early-stage of DR was investigated in 1-month-diabetic mice treated with phlorizin (two daily subcutaneous injections at a dose of 200 mg/kg of body weight during the last 7 full days of the experiment and the morning of the 8th day, 3 h before sacrifice) or rapamycin (daily intraperitoneal injections, at a dose of 3 mg/kg for the same period as for phlorizin treatment). The effect of autophagy modulation on retinal ganglion cells was investigated in 3-months-diabetic mice treated with phlorizin (two daily subcutaneous injections during the last 10 full days of the experiment and the morning of the 11th day, 3 h before sacrifice) or MHY1485 (daily i.p. injections, at a dose of 10 mg/kg for the same period as for phlorizin treatment). Tissue samples obtained from treated/untreated diabetic mice and age-matched controls were used for Western blot and histologic analysis. RESULTS: mTOR-related proteins and glucose transporter 1 (GLUT1) was upregulated at 1 month and downregulated in the following period up to 6 months. Diabetes-induced neurodegeneration was characterized by an increase of apoptotic marker-cleaved caspase 3, a decrease of the total number of cells, and NeuN immunoreactivity in the ganglion cell layer, as well as an increase of autophagic protein. Insulin-independent glycemic control restored the mTOR pathway activity and GLUT1 expression, along with a decrease of autophagic and apoptotic proteins in 3-months-diabetic mice neuroretina. However, blockade of autophagy using MHY1485 resulted in a more protective effect on ganglion cells compared with phlorizin treatment. CONCLUSION: Collectively, our study describes the mechanisms of neurodegeneration through the hyperglycemia/ mTOR/ autophagy/ apoptosis pathway. Video Abstract.

mTORC1 and mTORC2 are differentially engaged in the development of laser-induced CNV.

BACKGROUND: The mechanistic target of rapamycin (mTOR) pathway is a potential target to inhibit pathologic processes in choroidal neovascularization. However, the exact role of mTOR signaling in the development of CNV remains obscure. In this study, we assessed the role of mTORC1 and mTORC2 as well as the effect of rapamycin (sirolimus) on choroidal neovascularization (CNV) in a laser-induced mouse model. METHODS: In experiment A, we observed the natural course of CNV development and the dynamics of mTOR-related proteins during the 12 days after the laser injury. The expression of mTOR-related proteins was evaluated using Western blot (WB). Cryosections of CNV-induced mice were immunostained for the visualization of the vascular and extravascular components of the CNV. Experiment B was performed to confirm the critical period of mTOR signaling in the development of laser-induced CNV, we administered rapamycin before and/or during the active period of mTOR complexes. WB and immunofluorescence staining was performed to evaluate the mode of action and the effect of mTOR inhibition on CNV development. RESULTS: In experiment A, we detected high levels of p-mTOR S2448 and p-mTOR S2481 from the 5th to 12th day of laser injury. Immunofluorescence imaging of cryosections of mice sacrificed on day 7 revealed greater co-immunoreactivity of p-mTOR S2448 positive cells with CD11b and F4/80, while p-mTOR S2481 positive cells showed colocalization with CD31, α-SMA, and cytokeratin. In experiment B, rapamycin injection during the active period of mTOR signaling demonstrated near-complete inhibition of CNV lesion as well as significant induction of autophagy. CONCLUSION: Our study suggests the mTOR as a critical player during CNV development in laser-induced mouse model through differentially acting with the mTORC1 and mTORC2. mTORC1 activity was high predominantly in inflammatory cells in CNV lesion, while mTORC2 activity was higher in vascular components and the RPE.

Essential Role of mTOR Signaling in Human Retinal Pigment Epithelial Cell Regeneration After Laser Photocoagulation.

This study assessed the role of mechanistic target of rapamycin (mTOR) pathway in the human adult retinal pigment epithelial (ARPE) cell response after laser photocoagulation (LP). The effect of mTOR inhibition on ARPE-19 cell was investigated by rapamycin treatment after LP. Cell viability and proliferation were explored using MTT and EdU assays, respectively. The expression of mTOR-related proteins and epithelial-mesenchymal transition (EMT) markers was verified by Western blot. Rapamycin retarded the LP area recovery in a dose-dependent manner by the 120 h, while LP+DMSO vehicle-treated cells completely restored the lesion zone (P ≤ 0.01). ARPE-19 cell viability is significantly lower in LP + rapamycin 80 and 160 ng/ml treated cultures compared to LP control at 120 h (P ≤ 0.001). LP control group demonstrated significantly more proliferative cells compared to untreated cells at the 72 and 120 h, whereas EdU-positive cell numbers in cultures treated with rapamycin at concentrations of 80 and 160 ng/ml were similar to baseline values (P ≤ 0.01). mTOR pathway activation is essential for regulation of the RPE cell migration and proliferation after LP. mTOR inhibition with rapamycin effectively blocks the migration and proliferation of the RPE cells. Our results demonstrate that mTOR has an important role in ARPE-19 cell as a regulator of cell behavior under stress conditions, suggesting that mTOR could be a promising therapeutic target for numerous retinal diseases.

The role of Wnt/ß-catenin signaling in the restoration of induced pluripotent stem cell-derived retinal pigment epithelium after laser photocoagulation.

To investigate the role of Wnt/ß-catenin signaling pathway in the restoration of induced pluripotent stem cell-derived retinal pigment epithelium (hiPSC-RPE) after laser photocoagulation. After differentiation of RPE cells from hiPSCs, laser photocoagulation was performed. Activation of Wnt/ß-catenin signaling at days 1 and 5 after laser photocoagulation was evaluated by expression of ß-catenin. Cell proliferation and alteration in cell-to-cell contact at day 5 after laser photocoagulation with or without Dickkopf-1 (Dkk-1) treatment were studied using ethynyl-2'-deoxyuridine (EdU) assay and zonula occludens-1 (ZO-1) expression analysis, respectively. The mRNA levels of Wnt genes at day 5 after laser photocoagulation were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Activation of Wnt/ß-catenin signaling at days 1 and 5 after laser photocoagulation was confirmed by ß-catenin accumulation in the cytoplasm and nucleus of hiPSC-RPE. Many EdU-positive cells also expressed ß-catenin, and the number of EdU-positive cells was decreased at day 5 after laser photocoagulation after Dkk-1 treatment, indicating that Wnt/ß-catenin signaling mediated hiPSC-RPE proliferation. ZO-1 expression was not decreased with Dkk-1 treatment at day 5 after laser photocoagulation, indicating that Wnt/ß-catenin signaling mediated hiPSC-RPE restoration. At day 5, after laser photocoagulation, mRNA levels of Wnt2b, Wnt3, Wnt5a, Wnt7a, and Wnt10b were increased. Wnt/ß-catenin signaling has a crucial role in restoration of hiPSC-RPE proliferation after laser photocoagulation. Manipulation of Wnt/ß-catenin signaling while elucidating the underlying mechanisms of RPE restoration might have a therapeutic potential in retinal degenerative diseases.

The retinal pigment epithelial response after retinal laser photocoagulation in diabetic mice.

To investigate the characteristics of regenerated retinal pigment epithelial (RPE) cells after retinal laser photocoagulation in diabetic mice. C57BL/6J mice were used to induce diabetes using intraperitoneal injection of streptozotocin. The proliferation of RPE cells after laser photocoagulation was determined using the 5-ethynyl-2'-deoxyuridine (EdU) assay in both diabetic and wild-type mice. The morphological changes of RPE cells were evaluated by using Voronoi diagram from immunostaining for ß-catenin. Characteristics of regenerated cells were evaluated by quantifying the mRNA and protein levels of RPE and epithelial-mesenchymal transition (EMT) markers. There were significantly less EdU-positive cells in laser-treated areas in diabetic mice than wild-type mice. Hexagonality was extensively lost in diabetic mice. Many EdU-positive cells were co-localized with Otx2-positive cells in the center of the laser-treated areas in wild-type mice, but only EdU-positive cells were widely distributed in diabetic mice. Quantitative analysis of mRNA and protein levels showed that the expression levels of RPE markers, Pax6, Mitf, and Otx2, were significantly decreased in RPE of diabetic mice compared with that of wild-type mice, whereas the expression levels of EMT markers, vimentin and fibronectin, were significantly increased. The proliferation and hexagonality of regenerating RPE cells were impaired after laser photocoagulation, and the regenerated RPE cells lost their original properties in diabetic mice. Further clinical research is needed to elucidate the RPE response after laser photocoagulation in diabetic patients.

Comparison of the neuroinflammatory responses to selective retina therapy and continuous-wave laser photocoagulation in mouse eyes.

PURPOSE: This study investigated microglia and inflammatory cell responses after selective retina therapy (SRT) with microsecond-pulsed laser in comparison to continuous-wave laser photocoagulation (cwPC). METHODS: Healthy C57BL/6 J mice were treated with either a train of short pulses (SRT; 527-nm, Q-switched, 1.7-µs pulse) or a conventional thermal continuous-wave (532-nm, 100-ms pulse duration) laser. The mice were sacrificed and their eyes were enucleated 1, 3, 7, and 14 days after both laser treatments. Pattern of cell death on retinal section was evaluated by TUNEL assay, and the distribution of activated inflammatory cells and glial cells were observed under immunohistochemistry. Consecutive changes for the expression of cytokines such as IL-1ß, TNF-α, and TGF-ß were also examined using immunohistochemistry, and compared among each period after quantification by Western blotting. RESULTS: The numbers of TUNEL-positive cells in the retinal pigment epithelium (RPE) layer did not differ in SRT and cwPC lesions, but TUNEL-positive cells in neural retinas were significantly less on SRT. Vague glial cell activation was observed in SRT-treated lesions. The population of inflammatory cells was also significantly decreased after SRT, and the cells were located in the RPE layer and subretinal space. Proinflammatory cytokines, including IL-1ß and TNF-α, showed significantly lower levels after SRT; conversely, the level of TGF-ß was similar to the cwPC-treated lesion. CONCLUSIONS: SRT resulted in selective RPE damage without collateral thermal injury to the neural retina, and apparently produced negligible glial activation. In addition, SRT showed a markedly less inflammatory response than cwPC, which may have important therapeutic implications for several macular diseases.

Nestin Expression in the Adult Mouse Retina with Pharmaceutically Induced Retinal Degeneration.

The present study investigated the temporal pattern and cellular localization of nestin in the adult mouse retina with pharmaceutically induced retinal degeneration using N-methyl-N-nitrosourea (MNU). After a single intraperitoneal injection of MNU in 8-week-old C57BL/6 mice, the animals were sacrificed at 1, 3, 5, 7, and 21 days (n = 6, in each stage). The eyes were examined by means of immunohistochemical tests using nestin, ionized calcium-binding adaptor molecule (Iba-1), CD11b, F4/80, and glial fibrillary acidic protein (GFAP). Western blot analysis and manual cell counting were performed for quantification. Nestin expression was increased after MNU administration. Nestin+/Iba-1+ cells were migrated into outer nuclear layer (ONL) and peaked at day 3 post injection (PI). Nestin+/CD11b+ cells were also mainly identified in ONL at day 3 PI and peaked at day 5. Nestin+/F4/80+ cells were shown in the subretinal space and peaked at day 3 PI. Nestin+/GFAP+ cells were distinctly increased at day 1 PI and peaked at day 5 PI. The up-regulation of nestin expression after MNU administration in adult mouse retinal microglia, and monocyte/macrophage suggests that when retinal degeneration progresses, these cells may revert to a more developmentally immature state. Müller cells also showed reactive gliosis and differentiational changes.

Expression of Aquaporin-6 in Rat Retinal Ganglion Cells.

Several aquaporins (AQPs) have been identified to be present in the eyes, and it has been suggested that they are involved in the movement of water and small solutes. AQP6, which has low water permeability and transports mainly anions, was recently discovered in the eyes. In the present study, we investigate the localization of AQP6 in the rat retina and show that AQP6 is selectively localized to the ganglion cell layer and the outer plexiform layer. Along with the gradual decrease in retinal ganglion cells after a crushing injury of optic nerve, immunofluorescence signals of AQP6 gradually decreased. Confocal microscope images confirmed AQP6 expression in retinal ganglion cells and Müller cells in vitro. Therefore, AQP6 might participate in water and anion transport in these cells.

Linezolid induced retinopathy.

PURPOSE: While optic neuropathy is a well-known cause of visual disturbances in linezolid-treated patients, the possibility of linezolid-related retinopathy has not been investigated. Here, we report a case of retinopathy demonstrated by multifocal electroretinogram (mfERG) in a linezolid-treated patient. METHOD AND RESULTS: A 61-year-old man with extensively drug-resistant pulmonary tuberculosis treated with linezolid for 5 months presented with painless loss of vision in both eyes. The patient's best corrected visual acuity was 20/50 in the right eye and 20/100 in the left eye. Fundus examination revealed mild disc edema, and color vision was defective in both eyes. Humphrey visual field tests showed a superotemporal field defect in the right eye and central and pericentral field defect in the left eye. Optical coherence tomography (OCT) revealed only mild optic disc swelling. In mfERG, central amplitudes were depressed in both eyes. Four months after the cessation of linezolid, visual acuity was restored to 20/20 right eye and 20/25 left eye. The color vision and visual field had improved. The OCT and mfEFG findings improved as well. CONCLUSIONS: Although the clinical features were similar to linezolid-induced optic neuropathy, the mfERG findings suggest the possibility of a retinopathy through cone dysfunction.

Low-fluence photodynamic therapy versus ranibizumab for chronic central serous chorioretinopathy: one-year results of a randomized trial.

PURPOSE: To compare the efficacy and safety between low-fluence photodynamic therapy (PDT) and the intravitreal ranibizumab in the treatment of chronic central serous chorioretinopathy (CSC). DESIGN: Prospective, randomized, single-center, parallel-arm, controlled trial. PARTICIPANTS: Thirty-four eyes of 32 patients with chronic CSC with >6 months' duration of symptoms or recurrent CSC were randomly placed into the low-fluence PDT group (n = 18) or the ranibizumab group (n = 16). INTERVENTION: The patients underwent a single session of low-fluence PDT or 3 consecutive monthly injections of ranibizumab. Rescue treatment was available from month 3 if the subretinal fluid (SRF) persisted or recurred after primary treatment; low-fluence PDT was given to the ranibizumab group and intravitreal ranibizumab to the low-fluence PDT group. MAIN OUTCOME MEASURES: The primary outcome was the proportion of eyes with complete resolution of SRF without rescue treatment. Secondary outcomes included the mean changes in logarithm of the minimum angle of resolution best-corrected visual acuity (BCVA), central retinal thickness (CRT), and angiographic findings from baseline to 12 months. RESULTS: At month 12, 16 eyes (88.9%) of the low-fluence PDT group maintained complete resolution of SRF without rescue treatment versus 2 eyes (12.5%) in the ranibizumab group (P <0.001). Two eyes (11.1%) in the low-fluence PDT group and 11 eyes (68.8%) in the ranibizumab group met the criteria for rescue treatment (P = 0.001). In the low-fluence PDT group, the mean decrease in CRT from baseline was significantly greater than that in the ranibizumab group until month 6 (P <0.05), but the differences became insignificant thereafter. The improvement in BCVA from baseline was superior in the low-fluence PDT group to that in the ranibizumab group, but the differences were not statistically significant except at month 3 (P = 0.025). On indocyanine green angiography, a significantly greater proportion of the low-fluence PDT group (16 eyes; 88.9%) showed a marked reduction in choroidal hyperpermeability after primary treatment than that of the ranibizumab group (0 eyes; P <0.001). No serious adverse events related to the drugs or procedures were observed. CONCLUSIONS: This study represents the overall superiority of low-fluence PDT compared with intravitreal ranibizumab in the treatment of chronic CSC.

Endogenous endophthalmitis in the Korean population: a six-year retrospective study.

PURPOSE: To identify the clinical features, treatment outcomes, and prognostic factors of endogenous endophthalmitis in multiple tertiary referral centers of South Korea over a 6-year period. METHODS: The authors conducted a retrospective review of medical records of 57 eyes of 43 patients diagnosed with endogenous endophthalmitis from January 2005 to December 2011, which was referred to tertiary referral centers. RESULTS: Fifty-seven cases of 43 patients were followed for a mean of 18.7 months (range, 0.5-50 months). The common underlying diseases were diabetes mellitus (46.5%) and liver cirrhosis (20.93%). Liver abscess (39.5%) was the most common infection source. Among prognostic factors, the initial visual acuity was associated with favorable visual outcome significantly (P < 0.001). Endogeneous endophthalmitis with gram-negative bacteria had worse visual outcomes than gram-positive bacteria or fungus (P = 0.014). CONCLUSION: Similar to the findings of previous East Asian studies, this study showed that Klebsiella pneumoniae was the most common causative organism of endogenous endophthalmitis and liver abscess was the most common infection focus. Although endogenous endophthalmitis is generally associated with poor visual acuity outcomes, the prognosis depends mainly on the initial visual acuity and the pathogen.

Intranasal delivery of the cytoplasmic domain of CTLA-4 using a novel protein transduction domain prevents allergic inflammation.

CTLA-4 is a negative regulator of T-cell activation, and its inhibitory effects can be accomplished either by competition with CD28 or by transmitting negative signals through its intracellular domain. To utilize the cytoplasmic domain of CTLA-4 to suppress allergic inflammation, we fused it to a novel protein-transduction domain in the human transcriptional factor Hph-1. Transduction efficiency was verified in vitro and in vivo after ocular, intranasal and intradermal administration. After transduction into T cells, the Hph-1-ctCTLA-4 fusion protein inhibited the production of interleukin (IL)-2, and downregulated CD69 and CD25. Intranasal administration of Hph-1-ctCTLA-4 resulted in markedly reduced infiltration of inflammatory cells, secretion of T helper type 2 (T(H)2) cytokines, serum IgE levels and airway hyper-responsiveness in a mouse model of allergic airway inflammation. These results indicated that Hph-1-ctCTLA-4 constitutes an effective immunosuppressive protein drug for potential use in the treatment of allergic asthma, via nasal administration.

Evaluation of structural and functional changes in non-pathologic myopic fundus using multifocal electroretinogram and optical coherence tomography.

PURPOSE: To evaluate structural and functional changes in non-pathologic myopic fundus using multifocal electroretinogram (mfERG) and spectral domain-optical coherence tomography (SD-OCT). METHODS: A total of 90 myopic subjects underwent mfERG and SD-OCT. The subjects were divided into four groups according to spherical equivalent refractive error: Group 1 (-0.50 to -2.75 D), Group 2 (-3.00 to -5.75 D), Group 3 (-6.00 to -9.75 D), and Group 4 (-10.0 to -15.0 D). Total retinal thickness, photoreceptor retinal thickness (PR), outer nuclear retinal thickness and mid-inner retinal thickness (MIR) were measured using SD-OCT in foveola and two perifoveal retinal regions 2.0 mm nasal and temporal from the foveola. The amplitude and implicit time of N1 and P1 mfERG responses were analyzed using six-concentric-ring grouping. Correlations between each retinal thickness, amplitude, and implicit time among the four myopic groups were analyzed. RESULTS: PR thickness in the foveola and MIR thickness in the perifoveal retina were significantly reduced with increasing myopic refractive errors (p = 0.001, respectively). Significant correlations appeared between N1 amplitude, P1 amplitude, P1 implicit time, and refractive errors (p = 0.001, respectively). Significant correlations appeared between MIR thickness and N1, P1 amplitude (p = 0.001, respectively) as well as N1, P1 implicit time (p = 0.02 and 0.03, respectively) in the perifoveal retina corresponding to ring 4. CONCLUSIONS: The correlation between structural and functional changes in myopia should be considered when interpreting retinal structure and function using SD-OCT and mfERG, especially in high myopia.

Extrafoveal changes following intravitreal bevacizumab injections for macular edema secondary to branch retinal vein occlusion: an mfERG and OCT study.

PURPOSE: To evaluate the functional and structural changes of extrafoveal macula after intravitreal bevacizumab (IVB) injection in patients with macular edema due to branch retinal vein occlusion (BRVO) using multifocal electroretinogram (mfERG) and optical coherence tomography (OCT). METHODS: A total of 19 eyes of 19 patients with macular edema due to BRVO received three consecutive IVB injections with a 6-week interval. Spectral domain optical coherence tomography (SD-OCT), mfERG, and fluorescein angiography (FA) were performed at baseline. The macular area was divided into four quadrants (Q1-Q4) based on FA. The mean retinal thickness (MRT) and mfERG parameters in each of the four quadrants were measured at baseline and 4 weeks after the third injection. RESULTS: The MRT in the four quadrants improved significantly after IVB injections (p < 0.01 for Q1 and Q2, p < 0.05 for Q3 and Q4) compared to baseline. The significant improvements in mfERG responses were seen in Q1 and Q2. In Q1, there were 68 and 56% improvement in N1 and P1 amplitude, respectively (p < 0.01). N1 and P1 amplitude in Q2 increased significantly by 43 and 46%, respectively, compared to baseline (p < 0.05). The MRT and P1 amplitude were significantly correlated at baseline in Q1 and Q2, but no significant correlations were found after three IVB injections. CONCLUSIONS: The injection of IVB improved functional and structural outcomes in the primarily affected half of the extrafoveal macula effectively. The measurements of structural and functional changes using mfERG and OCT may be appropriate for monitoring the effects of IVB injection in BRVO patients.

Visual prognostic value of photopic negative response and optical coherence tomography in central retinal vein occlusion after anti-VEGF treatment.

OBJECTIVE: To investigate the potential of optical coherence tomography (OCT) and photopic negative response (PhNR) for predicting visual outcome after intravitreal bevacizumab in patients with macular edema secondary to central retinal vein occlusion (CRVO). METHODS: Thirty-two consecutive patients with macular edema secondary to unilateral CRVO who were treated with three times of 6 weeks interval intravitreal bevacizumab were enrolled. LogMAR visual acuity (Va), OCT and PhNR were done before and 4 weeks after first and third injection. Stepwise multiple regression analysis was conducted between pre-treatment Va, central retinal thickness, b wave amplitude, PhNR amplitude, PhNR relative amplitude (affected eye/unaffected fellow eye, % presentation) and post-treatment Va at 4 weeks after the third injection. The predictive values of pre-treatment parameters for good visual outcome (0.2 ≤ LogMAR Va) were assessed using receiver-operating characteristics (ROC) analysis. RESULTS: In multiple regression analysis, pre-treatment Va (ß = 0.615, P = 0.001) and PhNR relative amplitude (ß = -0.352, P = 0.032) were correlated significantly with post-treatment Va. In ROC analysis, pre-treatment Va showed a 80 % sensitivity and 80 % specificity for predicting good visual outcome, at a cutoff value of 0.52 LogMAR. Pre-treatment PhNR relative amplitude demonstrated a 88 % sensitivity and 75 % specificity for predicting good visual outcome, at a cutoff value of 40.00 %. CONCLUSIONS: The PhNR relative amplitude can be a useful prognostic factor for visual outcome after intravitreal bevacizumab therapy in patient with macular edema secondary to CRVO. Patients with larger pre-treatment PhNR relative amplitude with better pre-treatment Va showed a better post-treatment visual outcome.

Short-term Efficacy and Safety of Intravitreal Brolucizumab Injection for Treatment-Naive Exudate Age-related Macular Degeneration: A Multicenter Study.

PURPOSE: To compare short-term efficacy and safety of intravitreal brolucizumab injection with aflibercept in treatment-naive neovascular age-related macular degeneration (nAMD) patients. METHODS: A total of 59 eyes from 59 treatment-naive nAMD patients in three hospitals were retrospectively reviewed. Of which, 27 patients underwent intravitreal brolucizumab injections and 32 received aflibercept. After monthly consecutive three injections, best-corrected visual acuity (BCVA; in logarithm of minimal angle of resolution [logMAR]), central macular thickness (CMT), dry macula achievement rate, and intraocular inflammation (IOI) incidence were compared. RESULTS: After loading-phase treatment, BCVA was significantly increased from 0.48 ± 0.30 logMAR at baseline to 0.33 ± 0.21 logMAR at 3 months in the brolucizumab group (p = 0.002) and 0.40 ± 0.39 logMAR at baseline to 0.33 ± 0.36 logMAR at 3 months in the aflibercept group (p = 0.007). But there was no significant difference in BCVA improvement at 3 months between the two groups. CMT significantly decreased from 429.67 ± 250.59 µm at baseline to 210.67 ± 93.53 µm at 3 months in the brolucizumab group and from 346.69 ± 159.09 µm to 234.52 ± 83.42 µm in the aflibercept group (both p < 0.001). The amount of CMT reduction was significantly greater in the brolucizumab group after 3 months (p = 0.036). In typical AMD eyes, brolucizumab showed similar BCVA improvement but better CMT reduction at 3 months (p = 0.018). Dry macula achievement rate was not significantly different between the two groups. One IOI was observed in the brolucizumab group. CONCLUSIONS: Intravitreal injections of brolucizumab and aflibercept showed similar anatomical and functional outcomes. But CMT reduction was greater in the brolucizumab group. One IOI was identified, which was tolerable for topical agents. These results suggest that brolucizumab could be a novel first line treatment option for treating naive nAMD patients.