Clinicopathological findings in refractory diabetic macular edema: A case report.

The present study describes the case of a patient with refractory diabetic cystoid macular edema who underwent vitrectomy with en bloc removal of the cystoid lesion component. The current study also performed histopathological and immunohistochemical analyses of the cystoid lesion component to assess fibrin/fibrinogen and advanced glycation end-products (AGEs) immunoreactivity. A 69-year-old Japanese man presented with visual loss in the left eye due to residual cystoid macular edema (CME) refractory to anti-vascular endothelial growth factor therapy. Best-corrected visual acuity was 1.2 in the right eye (OD) and 0.5 in the left eye (OS). Fundus examination showed dot hemorrhages and hard exudates in the peri-macular region with pan-retinal photocoagulation scars in both eye. Swept-source optical coherence tomography revealed CME with slight hyperreflectivity in the cyst OS. A total of 3 months after the initial visit, pars plana vitrectomy was performed, and the translucent solidified component within the cystoid lesion was isolated. Histopathologically, the excised component was elliptical in shape, measuring 0.7x0.4 mm and exhibited homogeneous eosinophilic material without cellular components. No membranous structure was observed surrounding the component. Immunohistochemistry demonstrated that the tissue was positive for fibrin/fibrinogen and weakly positive for AGEs, but was negative for glial fibrillary acidic protein, type 1 collagen and receptor for AGEs. To the best of our knowledge, the present case report is the first to histopathologically examine the contents of refractory CME, and to immunohistochemically demonstrate that fibrin in diabetic CME may be post-translationally modified by AGEs. These results suggested that fibrin in CME may escape degradation by plasmin due to post-translational modifications.

Two-year clinical outcomes of triple therapy with photodynamic therapy, anti-vascular endothelial growth factor agent, and triamcinolone acetonide for neovascular age-related macular degeneration.

PURPOSE: To analyze the 2-year treatment outcomes of triple therapy with standard-fluence photodynamic therapy (PDT), intravitreal injection of ranibizumab (IVR)/aflibercept (IVA), and sub-tenon injection of triamcinolone acetonide (STTA) for neovascular age-related macular degeneration (nAMD) in Japanese patients. STUDY DESIGN: A retrospective, clinical case-series study. METHODS: Forty-four eyes of 44 patients with treatment-naïve nAMD followed for more than 24 months were evaluated. Initial treatment was given with triple therapy and retreatment with IVR/IVA as a pro re nata regimen. Best-corrected visual acuity (BCVA), central retinal thickness (CRT), the number of treatments, and intraocular pressure elevation were analyzed. RESULTS: The mean age was 73.3 ± 10.0 years. The mean BCVA significantly improved from 0.61 ± 0.30 at baseline to 0.50 ± 0.46 at 24 months (p = 0.034). CRT significantly improved from 373 ± 162 µm at baseline to 200 ± 107 µm at 24 months (p < 0.001). The number of treatments given during the 2-year treatment period was 2.7 ± 1.8. No retreatments were necessary in 18 of 44 eyes (40.9%), with no significant difference between IVR (46.4%) or IVA (31.3%) used during the 2-year follow-up of triple therapy (p = 0.51). Four eyes (9.1%) temporarily required glaucoma eye drop treatments. CONCLUSION: In nAMD patients, induction treatment with triple therapy resulted in approximately 40% of the patients requiring no retreatment for 2 years. The type of anti-VEGF agents used made no difference in the results.

Insidious progression of atrophic lesions in a case of posterior polar annular choroidal dystrophy.

Purpose: To describe the clinical course of a case of posterior polar annular choroidal dystrophy (PPACD) followed for 5 years. Observations: A 64-year-old female patient presented with blurred vision. The patient had no subjective symptoms of night blindness or visual field defects. At the initial visit, the patient's visual acuity was 20/20 in both eyes. Bilateral fundus examination revealed atrophic lesions surrounding the optic nerve head, extending to the temporal arcades in an annular pattern. Fundus autofluorescence (FAF) revealed hypoautofluorescent areas corresponding to atrophic lesions, and Goldmann perimetry revealed ring scotomas consistent with lesions in the fundus. Swept-source optical coherence tomography revealed retinal pigment epithelium atrophy, loss of the choriocapillaris, and dilation of the choroidal medium and large vessels in the atrophic area. Full-field electroretinography revealed a mild reduction in the combined rod-cone response. Laser speckle flowgraphy revealed a cold color in the posterior pole of both eyes. Based on clinical and imaging findings, the patient was diagnosed with PPACD and followed up for 5 years. At the 5-year visit, visual acuity remained unchanged, while FAF and Goldmann perimetry revealed a slight enlargement of the atrophic lesions and scotoma in both eyes, respectively. Conclusions and Importance: In the present case, atrophic lesions insidiously progressed and resulted in a slight enlargement of the hypoautofluorescent area and scotoma over a 5-year follow-up period, indicating that PPACD is a gradually progressive dystrophy.

Relationship between Brachial-Ankle Pulse Wave Velocity and Fundus Arteriolar Area Calculated Using a Deep-Learning Algorithm.

PURPOSE: Retinal vessels reflect alterations related to hypertension and arteriosclerosis in the physical status. Previously, we had reported a deep-learning algorithm for automatically detecting retinal vessels and measuring the total retinal vascular area in fundus photographs (VAFP). Herein, we investigated the relationship between VAFP and brachial-ankle pulse wave velocity (baPWV), which is the gold standard for arterial stiffness assessment in clinical practice. METHODS: Retinal photographs (n = 696) obtained from 372 individuals who visited the Keijinkai Maruyama Clinic for regular health checkups were used to analyze VAFP. Additionally, the baPWV was measured for each patient. Automatic retinal-vessel segmentation was performed using our deep-learning algorithm, and the total arteriolar area (AA) and total venular area (VA) were measured. Correlations between baPWV and several parameters, including AA and VA, were assessed. RESULTS: The baPWV was negatively correlated with AA (R = -0.40, n = 696, P < 2.2e-16) and VA (R = -0.36, n = 696, P < 2.2e-16). Independent variables (AA, sex, age, and systolic blood pressure) selected using the stepwise method showed a significant correlation with baPWV. The estimated baPWV, calculated using a regression equation with variables including AA, showed a better correlation with the measured baPWV (R = 0.70, n = 696, P < 2.2e-16) than the estimated value without AA (R = 0.68, n = 696, P < 2.2e-16). CONCLUSIONS: AA and VA were significantly correlated with baPWV. Moreover, baPWV estimated using AA correlated well with the actual baPWV. VAFP may serve as an alternative biomarker for evaluating systemic arterial stiffness.

Imbalanced choroidal circulation in eyes with asymmetric dilated vortex vein.

PURPOSE: Asymmetric dilated vortex vein (ADVV) observed in eyes with pachychoroid spectrum diseases is thought to be due to congestion of choroidal blood flow. The purpose of this study was to quantitatively investigate the blood flow velocity of ADVV using laser speckle flowgraphy (LSFG). STUDY DESIGN: Retrospective case series. METHODS: This was a retrospective case series with 23 eyes of 18 patients with ADVV on en-face OCT. A pair of choroidal veins from ADVV side (defined as ADVV vein) and non-ADVV side (defined as non-ADVV vein) was selected in each eye under the following criteria: (i) equivalent proximity to the deviated watershed, (ii) does not overlap with retinal blood vessels in the en-face OCT image, (iii) has approximately the same blood vessel diameter. Rubber bands were placed on the selected choroidal veins on the LSFG color map. Mean blur rate (MBR) values of ADVV and non-ADVV veins were statistically compared. RESULTS: The average MBR was 10.11 ± 1.9 in the ADVV veins and 13.49 ± 6.2 in the non-ADVV veins, showing significantly lower values in the ADVV veins (P = 0.03). The blood vessel diameter of the ADVV was 10.26 ± 3.0 and in the non-ADVV veins, 10.63 ± 2.9 pixels; not significantly different (P = 0.66). The distance from the deviated watershed to the ADVV was 53.3 ± 24.8 and to the non-ADVV veins, 46.80 ± 20.3 pixels; not significantly different (P = 0.41). CONCLUSION: In eyes with ADVV, the blood flow velocity in the ADVV veins was lower than in the non-ADVV veins, suggesting anatomical congestion of ADVV.

Choroidal vascular structures in diabetic patients: a meta-analysis.

PURPOSE: Choroidal vascular structures are likely to be affected in diabetic patients. The aim of this study was to conduct a meta-analysis of choroidal vascular structures in diabetic eyes with no diabetic retinopathy (NDR) and healthy control eyes, which was systematically evaluated by various factors involving the measurements. METHODS: This study identified clinical data from publications in PubMed and web of science until May 2020. Independent retrospective or prospective clinical studies comparing NDR and healthy control eyes regarding choroidal vascular structures were extracted. Five related studies were enrolled, cumulating in a total of 282 diabetic eyes and 511 control eyes examined in this study. Heterogeneity was statistically quantified by I2 statistics, and meta-analysis was performed using a random effects model. This study included 2 different algorisms of binarization determining the ratio of luminal areas in total choroidal areas, both of which were consolidated and called "choroidal vascular ratio." RESULTS: Meta-analysis clearly showed that the choroidal vascular ratio was significantly lower in NDR eyes than in healthy control eyes (weighted mean difference = - 2.16; 95%CI: - 3.19 to - 1.13; P < 0.005). Similar results were obtained in sub-analysis based on adjustment of serum HbA1c levels and duration of diabetes. CONCLUSIONS: The choroidal vascular ratio of NDR eyes was significantly lower than that of healthy control eyes. The ratio might contribute to a better understanding of the pathophysiology involved in the development of diabetic retinopathy, although there was some heterogeneity in primary analysis studies.

Comparison of clinical characteristics in patients with acute zonal occult outer retinopathy according to anti-retinal antibody status.

PURPOSE: To evaluate the clinical characteristics of patients with acute zonal occult outer retinopathy (AZOOR), according to the presence or absence of anti-retinal antibodies (ARAs) that are frequently detected in autoimmune retinopathy. METHODS: Retrospective observational case series. This study included 33 patients with acute-stage AZOOR who had been followed up for more than 6 months after the initial visit. The median follow-up period was 26 months. Immunoblot analyses were used to detect autoantibodies for recoverin, carbonic anhydrase II, and α-enolase in serum from these patients. Main outcome measures comprised clinical factors at the initial and final visits, including best-corrected visual acuity, mean deviation on Humphrey perimetry, and retinal morphology, which were statistically compared between patients with AZOOR who exhibited ARAs and those who did not. RESULTS: At least one serum ARA was detected in 42% of patients with AZOOR. There were no significant differences in clinical factors between the two groups, including follow-up period, best-corrected visual acuity and mean deviation at the initial and final visits, a-wave amplitude on single-flash electroretinography at the initial visit, and frequencies of improvement of the macular ellipsoid zone and AZOOR recurrence. CONCLUSIONS: Our findings suggest that the presence of ARAs did not influence visual outcomes or outer retinal morphology in patients with AZOOR.

Outcomes of a 2-year treat-and-extend regimen with aflibercept for diabetic macular edema.

This prospective, open-label, single-arm, non-randomized clinical trial, assessed the efficacy of a 2-year treat-and-extend (T&E) regimen involving intravitreal aflibercept injection (IAI), with the longest treatment interval set to 16 weeks, and adjunct focal/grid laser in diabetic macula edema (DME) patients. We examined 40 eyes (40 adults) with fovea-involving DME from 8 Japanese centers between April 2015 and February 2017. Participants received IAI with an induction period featuring monthly injections and a subsequent T&E period featuring 8-16-week injection interval, adjusted based on optical coherence tomography findings. The primary endpoints were mean changes in the best-corrected visual acuity (BCVA) and central subfield macular thickness (CST) from baseline. Thirty patients (75%) completed the 2-year follow-up. The mean BCVA and CST changed from 60.5 ± 15.6 letters and 499.2 ± 105.6 µm at baseline to 66.6 ± 17.1 letters (P = 0.217) and 315.2 ± 79.0 µm (P < 0.001), respectively, after 2 years. The treatment interval was extended to 12 and 16 weeks in 6.7% and 66.7% of patients, respectively, at the end of 2 years. The T&E aflibercept regimen with the longest treatment interval set to 16 weeks, with adjunct focal/grid laser may be a rational 2-year treatment strategy for DME.

Treat-and-extend therapy with aflibercept for diabetic macular edema: a prospective clinical trial.

PURPOSE: To investigate the efficacy and safety of a treat-and-extend (T&E) regimen using aflibercept (Eylea) for diabetic macular edema (DME). STUDY DESIGN: Prospective, open-label, multicenter, single-arm, nonblinded clinical study. METHODS: Forty eyes of 40 patients with DME received a T&E regimen of intravitreal aflibercept injection (IAI) with the longest treatment interval set to 16 weeks and adjunct focal/grid laser for 1 year. An intent-to-treat analysis was performed using the same last-observation-carried-forward method. A per-protocol analysis was also performed for patients who completed a 1-year T&E regimen. The primary endpoints were mean changes in best-corrected visual acuity (BCVA) and central subfield macular thickness (CST) from baseline. Secondary endpoints included IAI-interval extension and resultant IAI numbers and the association between an early response to IAI and final BCVA gain at 1 year. RESULTS: Thirty-one patients (77.5%) completed the 1-year aflibercept T&E regimen. In these per-protocol participants, the mean CST improvement/reduction was 187.3 ± 145.0 µm (P < .001), but the mean BCVA gain was limited to 4.3 ± 12.2 letters (P = .782). Subanalysis revealed that eyes that gained ≥ 4 letters (median at week 12) after the initial 3 consecutive IAIs (induction phase) achieved greater vision improvement (13.8 ± 9.5 letters) than did the residual eyes (- 4.3 ± 9.2 letters) at 1 year (P < .001). Treatment intervals were extended to 12 and 16 weeks in 16.1% (5/31) and 45.2% (14/31) of the patients, respectively. The mean IAI number was 7.0 ± 1.1. CONCLUSIONS: The results of this study suggest that although the BCVA improvement might be somewhat less than that of frequent treatment, a T&E aflibercept regimen with the longest treatment interval set to 16 weeks is a realizable rational strategy for DME treatment over 1 year.

A Deep Learning Architecture for Vascular Area Measurement in Fundus Images.

Purpose: To develop a novel evaluation system for retinal vessel alterations caused by hypertension using a deep learning algorithm. Design: Retrospective study. Participants: Fundus photographs (n = 10 571) of health-check participants (n = 5598). Methods: The participants were analyzed using a fully automatic architecture assisted by a deep learning system, and the total area of retinal arterioles and venules was assessed separately. The retinal vessels were extracted automatically from each photograph and categorized as arterioles or venules. Subsequently, the total arteriolar area (AA) and total venular area (VA) were measured. The correlations among AA, VA, age, systolic blood pressure (SBP), and diastolic blood pressure were analyzed. Six ophthalmologists manually evaluated the arteriovenous ratio (AVR) in fundus images (n = 102), and the correlation between the SBP and AVR was evaluated manually. Main Outcome Measures: Total arteriolar area and VA. Results: The deep learning algorithm demonstrated favorable properties of vessel segmentation and arteriovenous classification, comparable with pre-existing techniques. Using the algorithm, a significant positive correlation was found between AA and VA. Both AA and VA demonstrated negative correlations with age and blood pressure. Furthermore, the SBP showed a higher negative correlation with AA measured by the algorithm than with AVR. Conclusions: The current data demonstrated that the retinal vascular area measured with the deep learning system could be a novel index of hypertension-related vascular changes.

Morphological features of macular telangiectasia type 2 in Japanese patients.

PURPOSE: This study aimed to demonstrate the clinical course of Japanese patients with macular telangiectasia type 2 (MacTel-2). METHODS: This retrospective observational case series included 16 eyes of 8 Japanese patients (3 men and 5 women) with MacTel-2. The mean age and follow-up duration was 66.9 years and 42.8 months, respectively. Differences in best-corrected visual acuity (BCVA), funduscopic macular findings, central macular thickness (CMT), and the length of macular ellipsoid zone (EZ) loss were compared between the initial/baseline and final visits. Optical coherence tomographic changes in CMT by ≥ 20% and in EZ loss by ≥ 20% or ≥ 100 µm were defined as improved or worsened. RESULTS: Numerical changes in BCVA and EZ loss during follow-up were not statistically significant. However, the mean CMT at baseline, which was lower than that of healthy control eyes (P < 0.001), significantly increased during follow-up (P = 0.041). A certain proportion of eyes showed improvement in several parameters: funduscopic findings (both parafoveal retinal graying and foveal retinal pigment epithelium depigmentation) in 29% of eyes, CMT in 21% of eyes, and EZ loss in 43% of eyes. CONCLUSIONS: The non-negligible proportion of eyes with improved parameters, marked especially by macular EZ loss, suggests that Japanese patients with MacTel-2 have milder clinical features than Caucasian patients reported in the literature.

Choroidal Thickness in Diabetic Patients Without Diabetic Retinopathy: A Meta-analysis.

PURPOSE: To evaluate the relationship between diabetic eyes without diabetic retinopathy and healthy eyes in subfoveal choroidal thickness. DESIGN: Systematic review and meta-analysis. METHODS: An independent retrospective or prospective clinical study comparing diabetic eyes without diabetic retinopathy and healthy control eyes in the subfoveal choroidal thickness was selected. This study compiled data from publications in PubMed and Web of Science between January 1, 2008, and November 15, 2019. Heterogeneity was statistically quantified by I2 statistics, and meta-analysis was performed using a random-effects model. RESULTS: Seventeen related studies were identified, including a total of 4,213 eyes, which consisted of 1,197 diabetic eyes without diabetic retinopathy and 3,016 healthy eyes. Meta-analysis clearly showed that the subfoveal choroidal thickness of diabetic eyes without retinopathy was significantly thinner than that of healthy control eyes (weighted mean difference = -14.34 µm; 95% confidence interval: -24.37 to -4.32 µm; P < .005). Similar results were obtained in sub-analysis based on the adjustment of the axial length. CONCLUSIONS: This study suggests that the subfoveal choroidal thickness was thin in diabetic eyes without retinopathy compared to healthy eyes. Subfoveal choroidal thickness might be an important parameter for the development of diabetic retinopathy in diabetic eyes without retinopathy.

Alteration of choroidal vascular structure in diabetic macular edema.

PURPOSE: The aim of this study was to analyze choroidal structures in healthy subjects and patients with/without diabetic macular edema (DME). METHODS: This was a retrospective observation case control study. Four hundred and two eyes of patients with diabetes mellitus (DM), and 124 age-matched eyes of healthy subjects were enrolled in this study. DM patients were divided into 3 groups: presence of central-involved (CI) DME (n = 81) and nonCI-DME/non-DME (n = 321), based on OCT findings. Central choroidal thickness (CCT) and total choroidal, luminal, and stromal areas were determined using EDI-OCT and a binarization method, respectively. The luminal area expressed as a ratio of the total choroidal area was defined as the L/C ratio. RESULTS: DM eyes showed a significantly lower L/C ratio than control eyes, whereas there was no significant difference in CCT or total choroidal, luminal, or stromal areas. There was no significant difference between CI-DME and non-DME groups in HbA1c, blood pressure, dyslipidemia, or renal function. CCT and total choroidal, luminal, and stromal areas were significantly greater in the CI-DME group than non-DME group (each P < 0.05). CONCLUSIONS: These results suggest that CCT was thickened in the presence of DME, associated with both increased luminal and stromal areas, which might be related to the pathology of DME.

Relationship between diabetic macular edema and choroidal layer thickness.

PURPOSE: To investigate the relationship between diabetic macular edema (DME) and the choroidal layer thickness in diabetic patients. METHODS: This is a retrospective observation study. Three hundred eighteen eyes of 159 diabetes mellitus (DM) patients and age-matched 100 eyes of 79 healthy controls were enrolled. DME was defined as over 300 µm in the central retinal subfield of the Early Treatment Diabetic Retinopathy Study (ETDRS) grid sector. The central choroidal thickness (CCT), as well as inner and outer layers were determined based on enhanced depth imaging (EDI)-OCT. Diabetic patients with/without systemic diabetic treatments (DT) at the start of this study was defined as DT+ and DT-, respectively. The number of eyes examined was 62 and 256 eyes in DME+and DME-groups, respectively. DM patients were further subdivided into 4 groups with/without DME and DT; DME+DT+(35 eyes), DME-DT+(159 eyes), DME+DT-(27 eyes), and DME-DT-group (97 eyes). Multiple comparisons on CCT layers including control and each DM group were statistically examined. RESULTS: The total CCT layer was 254±83, 283±88, and 251±70 µm in the control, DME+, and DME-group, respectively. A total CCT layer in DME+was significantly thicker than the DME-group (P < 0.05). The outer CCT layer was 195±75, 222±83, and 193±63 µm in the control, DME+, and DME-group, respectively. The outer CCT layer in DME+ was significantly thicker than the DME-group (P < 0.05). In the subdivided groups, the total CCT layers in the control, DME+DT+, DME-DT+, DME+DT-and DME-DT-groups were 254±83, 274±88, 247±66, 290±84 and 258±75 µm, respectively. The outer CCT layers in each group were 195±75, 214±83, 189±58, 228±77, and 201±70 µm, respectively. Total CCT and the outer layer in DME+DT-was significantly thicker than the DME-DT+group (each P < 0.05). In contrast, there was no significant difference in inner layer between the groups. CONCLUSIONS: The total and outer CCT layers of diabetic eyes were significantly thickened in the DME+DT-as compared with the DME-DT+group, suggesting that CCT may be related to the pathology of DME.

Alteration of choroidal vascular structure in diabetic retinopathy.

PURPOSE: The aim of this study was to analyse choroidal structures in normal patients and patients with diabetes with various severities of diabetic retinopathy (DR). METHODS: This is a retrospective observation case control study. Three hundred and forty-two diabetic eyes, and age-matched 112 eyes without diabetes mellitus (DM) were enrolled in this study. Patients with DM were classified into no DR, mild/moderate non-proliferative DR (mNPDR), severe NPDR and proliferative DR (PDR). Patients with DM were further divided into two groups based on information regarding systemic DM treatment situation: DM-treated and untreated groups. Central choroidal thickness (CCT), and total choroidal area (TCA), luminal area (LA) and stromal area (SA) were determined using enhanced depth imaging optical coherence tomography and a binarisation method, respectively. The ratio of LA in the TCA was defined as L/C ratio. RESULTS: The haemoglobin A1c (HbA1c) value was significantly higher in the DM-untreated than in the DM-treated subjects. L/C ratio was significantly lower in all the diabetic eyes than control eyes (p<0.05). TCA, LA, L/C ratio and CCT were significantly greater in the DM-untreated than treated group (each p<0.05). In the DM-untreated group, TCA and LAs (p<0.05) and L/C ratio (p<0.01) were significantly lower in mNPDR subjects than normal controls (p<0.05). PDR in the DM-untreated group showed significantly larger SA and LA, and greater CCT than normal controls (each p<0.05). CONCLUSIONS: These results suggest that choroidal vasculature was initially involved at an early DR, whereas thickened LA and SA were noted in advanced DR.

Increased choroidal blood flow and choroidal thickness in patients with hypertensive chorioretinopathy.

PURPOSE: To investigate the alterations of central choroidal thickness (CCT) and macular choroidal blood flow in patients with hypertensive chorioretinopathy treated with antihypertensive agents. METHODS: In retrospective observational case series, ten eyes of 9 patients with hypertensive chorioretinopathy were enrolled (5 men and 4 women; 43.1 ± 19.6 years of age). CCT and mean blur rate (MBR) had been observed during follow-up using enhanced depth imaging optical coherence tomography and laser speckle flowgraphy, respectively. RESULTS: With the medication for hypertension, serous retinal detachment (SRD) disappeared in all the eyes (mean period, 57.8 ± 50.4 days), and the mean blood pressure decreased (122.7 ± 13.0 mmHg and 93.4 ± 13.2 mmHg at the initial visit and at the day of subretinal fluid absorption, respectively; P < 0.01). The mean logMAR value of best corrected visual acuity showed a tendency toward improvement with the resolution of SRD (0.15 ± 0.30 and 0.08 ± 0.28, P = 0.15). The average MBR significantly decreased when SRD was absorbed (11.4 ± 4.5 and 7.7 ± 2.2, P < 0.01). Similarly, the mean values of CCT decreased (473.2 ± 218.0 µm and 325.7 ± 112.0 µm, P < 0.01). The changing rates of CCT and MBR showed a significant positive correlation (P < 0.01, R = 0.88). CONCLUSION: The current study demonstrated a novel finding that choroidal blood flow velocity and thickness concurrently increased in the acute phase of hypertensive chorioretinopathy, suggesting the role of choroidal hyperperfusion in the pathogenesis of hypertensive chorioretinopathy.

Unsaturated Aldehyde Acrolein Promotes Retinal Glial Cell Migration.

Purpose: To investigate the effect of the unsaturated aldehyde acrolein on retinal glial cell migration. Methods: Müller glial cell markers expression in TR-MUL5 were confirmed by RT-PCR and immunostaining. Cell viability and migration rate of TR-MUL5 cells were assessed after the stimulation with acrolein. DNA microarray analysis was performed to analyze changes in the expression levels of migration-related genes in Müller glial cells stimulated with acrolein. Real-time PCR and ELISA were performed to validate DNA microarray analysis results. Inhibitors of C-X-C motif chemokine ligand 1 (CXCL1), one of the genes highly upregulated after the exposure to acrolein, and blockers of its receptor, CXCR2, were used to investigate the role of the CXCL1-CXCR2 axis on glial cell migration. CXCL1 concentration was measured in vitreous fluid samples obtained from proliferative diabetic retinopathy (PDR) and nondiabetic control eyes. CXCL1 and CXCR2 expression in glial cells of fibrovascular tissues obtained from PDR patients was examined by immunostaining. Results: At a high concentration, acrolein (100 µM) significantly decreased cell viability. However, in moderate, sublethal concentrations (25-50 µM), acrolein induced cell migration and substantially increased the production of CXCL1 in TR-MUL5 cells. CXCL1 concentration was significantly elevated in vitreous fluids of PDR patients, and CXCL1 and CXCR2 were present in glial cells in fibrovascular tissues of PDR patients. CXCL1 stimulation increased glial cell migration in a dose-dependent manner, which was abrogated by the neutralization of the CXCL1-CXCR2 axis. Conclusions: Our data demonstrate that acrolein promotes retinal Müller glial cell migration by enhancing CXCL1 production.

Increased thickness and decreased blood flow velocity of the choroid in a patient with acute macular neuroretinopathy.

BACKGROUND: The involvement of choroidal lesions in acute macular neuroretinopathy (AMN) is not yet fully understood. We quantitatively examined sequential changes in the morphology and circulation hemodynamics of the choroid using enhanced depth imaging optical coherence tomography (EDI-OCT) and laser speckle flowgraphy (LSFG) in a patient with AMN. CASE PRESENTATION: A 15-year-old boy was referred to our hospital due to AMN in his right eye alone. The next day AMN developed in his left eye. Three months later, AMN lesions in both eyes spontaneously resolved and the morphology of macular photoreceptors improved. Using EDI-OCT, central choroidal thickness (CCT) was examined for a period of three months, starting from the initial visit. Using LSFG, macular mean blur rate (MBR) was examined for three months, starting 1 week after the initial visit. At the first visit, CCT of the right eye with AMN was 82 µm higher than that of the left eye, which had not yet developed AMN, and decreased by 86 µm after three months. In the left eye, similarly, CCT increased by 16 µm after the AMN onset at 1 week compared with a pre-onset value at the first visit and thereafter decreased by 57 µm at 3 months. Macular MBR increased by 20-55% OD and 51-71% OS during the follow-up until 3 months. CONCLUSIONS: We found that the choroid at the macula thickened at the onset of AMN and became thin with the regression of disease. Therefore, in concert with MBR data, these results further strengthened our hypothesis that choroidal circulation impairment plays a role in the pathogenesis of AMN.

Proteolytic cleavage of vascular adhesion protein-1 induced by vascular endothelial growth factor in retinal capillary endothelial cells.

PURPOSE: To investigate the mechanism of soluble vascular adhesion protein-1 (sVAP-1) accumulation induced by vascular endothelial growth factor (VEGF) in the vitreous of patients with diabetic retinopathy (DR). STUDY DESIGN: Experimental. METHODS: Protein levels of sVAP-1 and N epsilon-(hexanoyl)lysine (HEL), an oxidative stress marker, in the vitreous samples from patients with proliferative diabetic retinopathy (PDR) with or without intravitreal bevacizumab (IVB) injection were determined by ELISA. The effect of VEGF on both mRNA expression of Vap-1 and secretion of sVAP-1 in rat retinal capillary endothelial cells (TR-iBRB2) was analyzed by real-time PCR and western blotting, respectively. In addition, the impact of VEGF on production and activation ratios of matrix metalloproteinase (MMP)-2 and MMP-9 was examined by gelatin zymography. Hydrogen peroxide production and reactive oxygen species (ROS) levels were assessed in the supernatants of TR-iBRB2 cells treated with VEGF. RESULTS: IVB injection decreased vitreous levels of sVAP-1 and HEL in patients with PDR. VEGF stimulation released sVAP-1 protein from TR-iBRB2 cells as a consequence of membrane-anchored VAP-1 shedding by MMP-2 and MMP-9. In addition, VEGF increased hydrogen peroxide generation and ROS augmentation through spermine oxidation by sVAP-1 as semicarbazide-sensitive amine oxidase (SSAO) in the supernatant of cultured endothelial cells. CONCLUSIONS: The current data demonstrate that proangiogenic factor VEGF induces sVAP-1 release from retinal capillary endothelial cells and facilitates hydrogen peroxide generation via enzymatic property of sVAP-1, followed by the increase of oxidative stress, one of the crucial factors in the pathogenesis of DR.