Macular Ischemia Changes in Patients with Diabetic Macular Edema Treated with Aflibercept and Ranibizumab.

Τhis study aims to assess changes in the fovea avascular zone (FAZ) in treatment naïve patients receiving aflibercept or ranibizumab injections for diabetic macular edema (DME). Best corrected visual acuity (BCVA) testing, OCT, and OCT-angiography imaging were performed at baseline and 1 month after each injection. Injections of either aflibercept or ranibizumab were administered monthly for 6 consecutive months. FAZ in the superficial (SCP) and the deep capillary plexus (DCP) using OCT angiography was recorded for each visit. Fifty eyes from fifty patients with a mean age of 67.0 ± 10.7 years were included in the study. Twenty-five patients received aflibercept and twenty-five received ranibizumab. BCVA was 40.8 ± 10.0 and increased to 52.1 ± 7.9 ETDRS letters at the last visit (p < 0.001). CRT was 295.6 ± 34.0 at baseline and 247.9 ± 29.7 at the last study visit (p < 0.001). SCP FAZ was 350.6 ± 79.5 µm2 at baseline and 339.0 ± 71.3 µm2 after sox monthly injections (p = 0.132). DCP FAZ was 558.6 ± 199.0 µm2 at baseline and 459.5 ± 156.1 µm2 after six monthly injections (p < 0.001). There was no effect of the choice of ranibizumab or aflibercept on DCP FAZ change (p = 0.277). In conclusion, treatment with 6 monthly injections of ranibizumab and aflibercept led to an increase in BCVA and a decrease in CRT and DCP FAZ area. Both drugs led to an improvement in DCP ischemia.

COVID-19 hemodynamic and thrombotic effect on the eye microcirculation after hospitalization: A quantitative case-control study.

BACKGROUND & OBJECTIVE: To quantify the hemodynamic and thrombotic effect of COVID-19 on the eye microcirculation of patients with thromboprophylaxis, shortly after hospital discharge. METHODS: This case-control study included 17 COVID-19 survivors (named "COVID-19 Group") and 17 healthy volunteers (named "Control Group"). Axial blood velocity (Vax) and percentage of occluded vessels (POV) were quantified by Conjunctival Video Capillaroscopy (CVC). Microvessels were identified and classified as "capillaries" (CAP), "postcapillary venules of size 1" (PC1), and "postcapillary venules of size 2" (PC2). RESULTS: The COVID-19 Group did not differ significantly in basic demographics from the Control Group. In the COVID-19 Group, there was a statistically significant (p < 0.001) reduction of Vax (39%, 49% and 47%, for CAP, PC1, and PC2, respectively) in comparison to the Control Group and a sizeable (p < 0.001) increase of POV (600%) in comparison to the Control Group. CONCLUSIONS: COVID-19 not only reduces significantly axial blood velocity in the capillaries and postcapillary venules of the eye but has also a devastating effect on microthrombosis (POV) despite thromboprophylaxis treatment. This gives a possible explanation for long COVID and a hint about the existence of a possibly unknown coagulation factor.

Quality-adjusted life years in macular oedema due to age-related macular degeneration, diabetes and central retinal vein occlusion: the impact of anti-VEGF agents in a tertiary centre in Greece.

INTRODUCTION: Neovascular age-related macular degeneration (nAMD), diabetic macular oedema (DME), and macular oedema due to central retinal vein occlusion (CRVO) are leading causes of vision loss, currently managed with anti-vascular endothelial growth factor injections (anti-VEGF). The aim of this study was to calculate QALYs in patients with nAMD, DME, and CRVO treated with anti-VEGF agents (QALYs+) in a Greek tertiary hospital setting and compare them to theoretical QALYs that the patients would have without treatment (QALYs-). MATERIAL AND METHODS: The study included 143 treatment-naive patients with macular oedema due to nAMD (n = 79), DME (n = 57), and CRVO (n = 7), who received anti-VEGF injections as monotherapy according to the Treat-and-Extend (T&E) protocol. The anti-VEGF agents were ranibizumab and aflibercept in equivalent fractions. QALYs where calculated by the formula QALY = Utility Value × Time, where "Time" refers to the follow-up period of the study. For QALYs-, we assumed that visual acuity remained unchanged during this period. RESULTS: Mean follow-up time was 1.3 ± 1.2 years in the nAMD group, 1 ± 1.3 years in the DME group, and 0.5 ± 1 years in the CRVO group. There was no statistically significant difference between QALYs- and QALYs+ in all three ocular pathologies for the study period (p > 0.05 for each of the three statistical tests performed). DISCUSSION/CONCLUSION: Possible explanations for the lack of significant difference between QALYs - and QALYs + in nAMD, DME, and CRVO groups, may be the short time horizon used in this analysis, the inclusion of data from the better-seeing eye (BSE) and the specific socio-economic, geographical and health care characteristics of this rural Greek area.

Optical coherence tomography angiography reveals vascular alterations in pediatric commotio retinae.

INTRODUCTION: Aim of this study is to present the acute and long-term swept-source optical coherence tomography angiography findings in pediatric commotio retinae. MATERIALS AND METHODS: Two children presented with reduced visual acuity and Berlin edema after blunt trauma. RESULTS: Swept-source optical coherence tomography revealed hyperreflectivity of the retinal nerve fiber layer and disruption of the ellipsoid zone and the retinal pigment epithelium. Swept-source optical coherence tomography angiography showed enlarged superficial foveal avascular zone in both cases. In the more severe case, there was enlargement of both superficial and deep foveal avascular zone, and reduction of the superficial vascular plexus density. CONCLUSION: The present findings suggest that pediatric commotio retinae may be associated with retinal vascular changes, that is, foveal avascular zone enlargement and decreased vessel density. The extent of the microvascular alterations is possibly related to trauma severity.

SLC2A1 Tag SNPs in Greek Patients with Diabetic Retinopathy and Nephropathy.

Backround: Genetic variants are implicated in the development of diabetic retinopathy (DR) and nephropathy (DN). The role of solute carrier family 2-facilitated glucose transporter member 1 (SLC2A1), also known as glucose transporter (GLUT1), on DR and DN remain controversial. OBJECTIVE: Examination of the influence of tag SLC2A1 single-nucleotide polymorphisms (SNPs) on the development of DR and DN during the course of type 2 diabetes mellitus (T2DM). METHODS: A total of 169 patients with DR or DN, 107 uncomplicated T2DM patients, and 315 controls were recruited and genotyped for 14 SLC2A1 tag SNPs. SNPs and haplotypes were tested for associations with microvascular diabetes' complications. RESULTS: rs3768029 TT genotype was associated with a lower risk of DR + DN, compared to the CC wild-type (p = 0.0024). Moreover, CT and TT rs841847 genotypes were associated with a higher risk of DR + DN compared to the CC genotype (p = 0.0028). A common haplotype (GGCCCGCATCAAT) was associated with an increased risk of DR, DN, DR ± DN, and DR + DN phenotypes. Mutational loads of rs3768029, rs3729548, rs841853, and rs841847 were found to influence the development of microvascular complications during the T2DM course. CONCLUSIONS: This study provides evidence that SLC2A1 gene variants might be implicated in the development of T2DM microvascular complications.

Plasminogen Activator Inhibitor Type-1 Tag Single-Nucleotide Polymorphisms in Patients with Diabetes Mellitus Type 2 and Diabetic Retinopathy.

BACKGROUND: There is accumulating evidence for genetic susceptibility to the development of diabetic retinopathy (DR). The role of plasminogen activator inhibitor-1 (PAI-1) in DR risk remains controversial. OBJECTIVE: The present study was designed to investigate possible influence of PAI-1 gene region polymorphisms on the risk of DR and on the risk of developing DR early vs late in the course of type 2 diabetes mellitus (T2DM). METHODS: A total of 138 patients with DR, 107 patients with T2DM without DR, and 315 healthy controls were recruited. To cover the majority of the genetic variability across the extended region of PAI-1 gene, five tag single-nucleotide polymorphisms (SNPs) from the HapMap using a pairwise approach and an r2 ≥ 0.8 and a minor allele frequency (MAF) of >0.05 were identified. Using logistic regression analyses, tag SNPs and haplotypes were tested for associations with DR risk and risk of DR development early or late in the course of T2DM. The generalized odds ratio (ORG) was calculated to estimate the mutational load effect on DR development among all participants. Corrections for multiple comparisons were carried out (p-value < 0.01). RESULTS: A significant effect of rs2070682 on the risk of early DR onset was found in the codominant model of inheritance [odds ratio, OR (95% confidence interval, CI): 5.04 (1.47-17.28), p = 0.018]. However, this association marginally did not survive multiple testing corrections. No other significant association between PAI-1 tag-SNPs and haplotypes was revealed. Furthermore, no significant mutational load effect of PAI-1 tag SNPs on the risk of DR development in T2DM course was found. CONCLUSIONS: In conclusion, the present study does not provide any strong evidence that PAI-1 gene variants are implicated in the risk of DR or the development of DR during T2DM course.

FLT1 genetic variation predisposes to neovascular AMD in ethnically diverse populations and alters systemic FLT1 expression.

PURPOSE: Current understanding of the genetic risk factors for age-related macular degeneration (AMD) is not sufficiently predictive of the clinical course. The VEGF pathway is a key therapeutic target for treatment of neovascular AMD; however, risk attributable to genetic variation within pathway genes is unclear. We sought to identify single nucleotide polymorphisms (SNPs) associated with AMD within the VEGF pathway. METHODS: Using a tagSNP, direct sequencing and meta-analysis approach within four ethnically diverse cohorts, we identified genetic risk present in FLT1, though not within other VEGF pathway genes KDR, VEGFA, or VASH1. We used ChIP and ELISA in functional analysis. RESULTS: The FLT1 SNPs rs9943922, rs9508034, rs2281827, rs7324510, and rs9513115 were significantly associated with increased risk of neovascular AMD. Each association was more significant after meta-analysis than in any one of the four cohorts. All associations were novel, within noncoding regions of FLT1 that do not tag for coding variants in linkage disequilibrium. Analysis of soluble FLT1 demonstrated higher expression in unaffected individuals homozygous for the FLT1 risk alleles rs9943922 (P = 0.0086) and rs7324510 (P = 0.0057). In silico analysis suggests that these variants change predicted splice sites and RNA secondary structure, and have been identified in other neovascular pathologies. These data were supported further by murine chromatin immunoprecipitation demonstrating that FLT1 is a target of Nr2e3, a nuclear receptor gene implicated in regulating an AMD pathway. CONCLUSIONS: Although exact variant functions are not known, these data demonstrate relevancy across ethnically diverse genetic backgrounds within our study and, therefore, hold potential for global efficacy.

Intravitreal bevacizumab for photodynamic therapy-induced massive macular detachment in acute central serous chorioretinopathy.

We present a long followed up case of acute central serous chorioretinopathy (CSC) complicated by a severe visual loss due to massive pigment epithelium detachment of the macula after a full-dose photodynamic therapy (PDT). Rapid anatomical and functional improvement was observed after a single intravitreal injection of bevacizumab. To our knowledge, we report the first case of PDT-treated CSC complicated by severe visual loss. We can only speculate that the serous detachment of the posterior pole might have been caused by PDT-induced VEGF overexpression, explaining such an impressive response to Avastin treatment.

Systems biology-based analysis implicates a novel role for vitamin D metabolism in the pathogenesis of age-related macular degeneration.

Vitamin D has been shown to have anti-angiogenic properties and to play a protective role in several types of cancer, including breast, prostate and cutaneous melanoma. Similarly, vitamin D levels have been shown to be protective for risk of a number of conditions, including cardiovascular disease and chronic kidney disease, as well as numerous autoimmune disorders such as multiple sclerosis, inflammatory bowel diseases and type 1 diabetes mellitus. A study performed by Parekh et al. was the first to suggest a role for vitamin D in age-related macular degeneration (AMD) and showed a correlation between reduced serum vitamin D levels and risk for early AMD. Based on this study and the protective role of vitamin D in diseases with similar pathophysiology to AMD, we examined the role of vitamin D in a family-based cohort of 481 sibling pairs. Using extremely phenotypically discordant sibling pairs, initially we evaluated the association of neovascular AMD and vitamin D/sunlight-related epidemiological factors. After controlling for established AMD risk factors, including polymorphisms of the genes encoding complement factor H (CFH) and age-related maculopathy susceptibility 2/HtrA serine peptidase (ARMS2/HTRA1), and smoking history, we found that ultraviolet irradiance was protective for the development of neovascular AMD (p = 0.001). Although evaluation of serum vitamin D levels (25-hydroxyvitamin D [25(OH)D]) was higher in unaffected individuals than in their affected siblings, this finding did not reach statistical significance. Based on the relationship between ultraviolet irradiance and vitamin D production, we employed a candidate gene approach for evaluating common variation in key vitamin D pathway genes (the genes encoding the vitamin D receptor [VDR]; cytochrome P450, family 27, subfamily B, polypeptide 1 [CYP27B1]; cytochrome P450, family 24, subfamily A, polypeptide 1 [CYP24A1]; and CYP27A1) in this same family-based cohort. Initial findings were then validated and replicated in the extended family cohort, an unrelated case-control cohort from central Greece and a prospective nested case-control population from the Nurse's Health Study and Health Professionals Follow-Up Studies, which included patients with all subtypes of AMD for a total of 2,528 individuals. Single point variants in CYP24A1 (the gene encoding the catabolising enzyme of the vitamin D pathway) were demonstrated to influence AMD risk after controlling for smoking history, sex and age in all populations, both separately and, more importantly, in a meta-analysis. This is the first report demonstrating a genetic association between vitamin D metabolism and AMD risk. These findings were also supplemented with expression data from human donor eyes and human retinal cell lines. These data not only extend previous biological studies in the AMD field, but further emphasise common antecedents between several disorders with an inflammatory/immunogenic component such as cardiovascular disease, cancer and AMD.

Influence of ROBO1 and RORA on risk of age-related macular degeneration reveals genetically distinct phenotypes in disease pathophysiology.

ROBO1 is a strong candidate gene for age-related macular degeneration (AMD) based upon its location under a linkage peak on chromosome 3p12, its expression pattern, and its purported function in a pathway that includes RORA, a gene previously associated with risk for neovascular AMD. Previously, we observed that expression of ROBO1 and RORA is down-regulated among wet AMD cases, as compared to their unaffected siblings. Thus, we hypothesized that contribution of association signals in ROBO1, and interaction between these two genes may be important for both wet and dry AMD. We evaluated association of 19 single nucleotide polymorphisms (SNPs) in ROBO1 with wet and dry stages of AMD in a sibling cohort and a Greek case-control cohort containing 491 wet AMD cases, 174 dry AMD cases and 411 controls. Association signals and interaction results were replicated in an independent prospective cohort (1070 controls, 164 wet AMD cases, 293 dry AMD cases). The most significantly associated ROBO1 SNPs were rs1387665 under an additive model (meta P = 0.028) for wet AMD and rs9309833 under a recessive model (meta P = 6 × 10(-4)) for dry AMD. Further analyses revealed interaction between ROBO1 rs9309833 and RORA rs8034864 for both wet and dry AMD (interaction P<0.05). These studies were further supported by whole transcriptome expression profile studies from 66 human donor eyes and chromatin immunoprecipitation assays from mouse retinas. These findings suggest that distinct ROBO1 variants may influence the risk of wet and dry AMD, and the effects of ROBO1 on AMD risk may be modulated by RORA variants.

Diabetic papillopathy in pregnancy: a marker for progression to proliferative retinopathy.

BACKGROUND: Diabetic papillopathy is an uncommon cause of transient acute optic disc edema, and during pregnancy it may be easily confused with other more serious disorders that may result in acute visual loss. CASE: We present a case of acute bilateral optic disc edema attributable to diabetic papillopathy in a young woman with an unplanned pregnancy and childhood-onset type 1 diabetes mellitus. The patient presented 16 months after fetal death of unknown etiology at 26 weeks of gestation with acute visual impairment in both eyes; severe proliferative retinopathy was diagnosed. Despite immediate therapeutic intervention with panretinal laser photocoagulation, the patient is legally blind. CONCLUSION: Early recognition of diabetic papillopathy in pregnancy is important to prevent unnecessary testing, invasive procedures, and inappropriate treatment. Patients with diabetic papillopathy should be monitored closely even after delivery because this condition may be associated with rapid progression to proliferative retinopathy.

Bimatoprost and bimatoprost/timolol fixed combination in patients with open-angle glaucoma and ocular hypertension.

PURPOSE: To investigate the intraocular pressure (IOP) lowering effect of bimatoprost (BIM) 0.03% and the potential additional effect of the BIM 0.03%/timolol 0.5% fixed combination (BTFC) in eyes with ocular hypertension, primary open-angle glaucoma, or exfoliation glaucoma. METHODS: Following an appropriate washout period that varied with previous medication, participants with ocular hypertension, primary open-angle glaucoma, or exfoliation glaucoma were treated with evening-dosed BIM for 5 weeks. They were then given evening-dosed BTFC for another 5 weeks. One randomly selected eye was evaluated. Goldmann applanation tonometry was performed by the same investigator at 8 a.m., 12 noon, 4 p.m., and 8 p.m. at baseline and at the end of each treatment period. RESULTS: Thirty-three participants completed the study. Three patients discontinued because of local adverse effects during the BIM treatment period. The mean diurnal IOP (mean ± SD) at baseline, on BIM, and on BTFC were 24.8 ± 5.4, 17.3 ± 3.5, and 14.9 ± 3.1 mmHg, respectively (repeated measures analysis of variance, P < 0.001 for all pairwise comparisons). The individual time-point IOP values showed similar significant reductions. The percentage of IOP reduction from baseline was 30.2% for BIM and 39.9% for the BTFC. The mean ± SD diurnal fluctuation at baseline was 6.8 ± 3.2 mmHg, which decreased to 4.0 ± 3.1 and 2.9 ± 1.4 mmHg on BIM and BTFC, respectively (P < 0.05 for both treatments versus baseline). CONCLUSIONS: Both BIM 0.03% and the BTFC were effective in lowering IOP in eyes with ocular hypertension and open-angle glaucoma. However, the fixed combination provided an additional statistically significant reduction in IOP compared with BIM 0.03%.

Plasma and aqueous humour levels of ghrelin in open-angle glaucoma patients.

BACKGROUND: To compare aqueous humour and plasma levels of ghrelin, a peptide recently identified in human eyes, in patients with open-angle glaucoma and controls. DESIGN: Cross-sectional, controlled, hospital-based study. PARTICIPANTS: Twenty-four open-angle glaucoma (17 primary open-angle and 7 pseudo-exfoliation glaucoma) patients and 30 controls were included. All participants were patients scheduled for cataract or glaucoma surgery. Patients with other ocular pathology, previous ocular surgery or diabetes were excluded. METHODS: Blood samples were collected before elective surgery. Aqueous humour was aspirated from the anterior chamber through a paracentesis with a 27-G needle under sterile conditions before any tissue manipulation. Ghrelin quantification was performed with commercially available Radioimmunoassay kits. MAIN OUTCOME MEASURE: Ghrelin levels in aqueous humour and plasma. RESULTS: Plasma levels of ghrelin were 490.5 ± 156.0 pg/mL in the open-angle glaucoma and 482.2 ± 125.4 pg/mL in the control group (Mann-Whitney test, P = 0.897). Aqueous humour levels of ghrelin were 85.5 ± 15.4 and 123.4 ± 25.5 pg/mL in the respective groups (P < 0.001). The ratio of plasma/aqueous humour ghrelin concentration was higher in the open-angle glaucoma versus the control group (5.75 ± 1.92 vs. 4.00 ± 1.04, P < 0.001). There was no difference in aqueous humour levels of ghrelin between primary open-angle glaucoma and pseudo-exfoliation glaucoma patients (P = 0.494). CONCLUSIONS: Aqueous humour levels of ghrelin were significantly lower in open-angle glaucoma patients, compared with controls. This difference may manifest a role of ghrelin in the disease process or a consequence of antiglaucoma treatment.

Blood velocity pulse quantification in the human conjunctival pre-capillary arterioles.

Axial red blood cell velocity pulse was quantified throughout its period by high speed video microcinematography in the human eye. In 30 conjunctival precapillary arterioles (6 to 12 microm in diameter) from 15 healthy humans, axial velocities ranged from 0.4 (the minimum of all the end diastolic values) to 5.84 mm/s (the maximum of all the peak systolic values). With the velocity pulse properly quantified, two parameters can be estimated: (1) the average velocity of the pulse during a cardiac cycle AVV (average velocity value) and (2) the magnitude of the pulsation using Pourcelot's resistive index RI. These parameters are important for the estimation of other hemodynamic parameters such as the average volume flow and the average shear stress. The results of this study revealed that the AVV in the human precapillary arterioles ranged between 0.52 and 3.26 mm/s with a mean value for all microvessels of 1.66 mm/s+/-0.11(SE). The RI ranged between 35.5% and 81.8% with a mean value of 53.1%+/-2.2. Quantitative information was obtained for the first time on the velocity pulse characteristics just before the human capillary bed.

Convergence of linkage, gene expression and association data demonstrates the influence of the RAR-related orphan receptor alpha (RORA) gene on neovascular AMD: a systems biology based approach.

To identify novel genes and pathways associated with AMD, we performed microarray gene expression and linkage analysis which implicated the candidate gene, retinoic acid receptor-related orphan receptor alpha (RORA, 15q). Subsequent genotyping of 159 RORA single nucleotide polymorphisms (SNPs) in a family-based cohort, followed by replication in an unrelated case-control cohort, demonstrated that SNPs and haplotypes located in intron 1 were significantly associated with neovascular AMD risk in both cohorts. This is the first report demonstrating a possible role for RORA, a receptor for cholesterol, in the pathophysiology of AMD. Moreover, we found a significant interaction between RORA and the ARMS2/HTRA1 locus suggesting a novel pathway underlying AMD pathophysiology.

Neovascular glaucoma as a first clinical manifestation of multiple sclerosis.

PURPOSE: To report a case with neovascular glaucoma caused by severe occlusive retinal vasculitis, as a first clinical manifestation of multiple sclerosis (MS). METHODS: Examination on an otherwise healthy 45-year-old man presenting with blurred vision in his right eye revealed bilateral iris neovascularization, right eye neovascular glaucoma, and bilateral retinal neovascularization caused by vasculitis. Thorough systemic investigation indicated by an ophthalmologist showed nothing else other than typical to MS imaging and spinal tap findings. The patient received bilateral treatment with panretinal photocoagulation and intravitreal bevacizumab (Avastin, Genentech, Inc., South San Francisco, CA) injection in the right eye. RESULTS: Ten months later, the patient was found with paraclinical neurologic findings completing the diagnostic criteria of definite laboratory supported MS. After the 3 years that followed, the ocular disease was eliminated, and the underlying disease remains clinically silent. CONCLUSION: As illustrated by our case, MS should be considered as an underlying disorder in patients with neovascular glaucoma caused by occlusive retinal vasculitis.

Evaluation of MMP1 and MMP3 gene polymorphisms in exfoliation syndrome and exfoliation glaucoma.

PURPOSE: To investigate possible genetic associations of matrix metalloproteinase-1 (MMP1) and MMP3 gene polymorphisms with exfoliation syndrome (XFS) with (XFS/+G) and without (XFS/-G) glaucoma in a cohort of Greek patients. METHODS: A total of 182 unrelated Greek patients with XFS, including 92 patients with XFS/+G, and 214 unrelated age- and gender-matched controls were enrolled in the study. MMP1 -1607 1G/2G (rs1799750) and MMP3 -1171 5A/6A (rs3025058) polymorphisms were determined using standard PCR/restriction fragment length polymorphism methods. Differences in allele and genotype distributions were analyzed using logistic regression. RESULTS: The distribution of genotypes and alleles in MMP1 and MMP3 polymorphisms was not significantly different between cases with exfoliation syndrome, with or without glaucoma, and controls. However, the allele contrast for the MMP1 variant showed a trend for a significant association with XFS/-G (Odds Ratio=1.47 [1.03-2.10]), since after correction for multiple comparisons, this association was no longer statistically significant. CONCLUSIONS: Our study provided some evidence of a possible role of the MMP1 variant in the development of exfoliation syndrome in Greek patients.