Efficacy of intravitreal ziv-aflibercept in patients with macular edema following retinal vein occlusion in Korle-Bu Teaching Hospital, Ghana: a retrospective case series.

AIM: To evaluate the efficacy of ziv-aflibercept in Ghanaian patients with macular edema (ME) secondary to retinal vein occlusion (RVO). METHODOLOGY: In this retrospective study, the medical records of patients with ME secondary to RVO who had been treated with intravitreal ziv-aflibercept (IVZ) (1.25 mg/0.05 ml), as part of routine clinical practice, on pro re nata basis with a minimum follow-up of 6 months were retrieved and analyzed. The main outcome measures are mean change in best-corrected visual acuity (BCVA) and central subfield foveal thickness (CSFT) measured on optical coherence tomography from baseline to 12 months post-IVZ, and ocular and systemic safety. RESULTS: Forty-three eyes were included in this study. Their mean age was 62.8 ± 11.9 years, 67.4% had at least 12-month duration of follow-up, 50% had primary open-angle glaucoma and 38 (88.4%) eyes were treatment naive. There was significant improvement in mean BCVA in LogMAR at 1 month post-initiation of IVZ (0.8 ± 0.5 vs. 1.1 ± 0.6), and visual improvement was maintained up to 12 months (p < 0.001). Eyes with ME following BRVO had better mean BCVA at baseline and on subsequent visits compared to eyes with CRVO/HRVO (p = 0.01). There was significant reduction in mean CSFT up to 12 months post-IVZ injection compared to baseline (p < 0.001). Ocular complications observed were consistent with complications associated with RVO. CONCLUSION: We have observed significant improvement in functional and anatomic outcomes 12 months post-initiation of IVZ. There is the need to confirm long-term efficacy and safety of IVZ in a large prospective study.

Biofeedback fixation training method for improving eccentric vision in patients with loss of foveal function secondary to different maculopathies.

PURPOSE: Fixation stability (FS) of the preferred retinal locus (PRL) may be improved by biofeedback fixation training (BFT) with microperimetry. Such training can be done on the patient's PRL or in different retinal loci with better functional characteristics. We studied both options and compared the outcomes. METHODS: Sixty-seven consecutive patients with bilateral central vision loss, poor FS and visual acuity (VA) lower than 0.3 LogMAR were recruited for BFT with microperimeter. Patients were assigned into 2 groups. In group A, BFT was performed on the patient's spontaneous PRL. In group B, PRL was located between 2 adjacent loci with the highest light sensitivity and the lowest distance from the fovea. Two sets of 12 weekly BFT sessions were performed. Primary outcomes were: FS, VA and reading speed. RESULTS: Outcomes were statistically significantly better in group B. Mean percentage of FS at therapy end improved from 32 to 35% for group A and from 40 to 55% in group B. Mean VA improved from 1 to 0.86 in group A and from 1 to 0.84 in group B. Reading speed (wpm) improved from 56 to 58 in group A and from 63 to 89 in group B. CONCLUSIONS: This study describes a reliable methodology of improving eccentric fixation stability using BFT in microperimetry, when the fixation training locus is individualized as the retinal area with best functional characteristics. Further studies are needed to validate its value in a larger scale of patients, at different stages of the disease, and its persistence over time.

Natural course of adult-onset vitelliform lesions in eyes with and without comorbid subretinal drusenoid deposits.

PURPOSE: Adult vitelliform lesions (AVL) are associated with age related macular degeneration (AMD) and subretinal drusenoid deposits (SRDD). We evaluated the natural course of AVL, assessing the influence of SRDD on disease progression, visual function and incidence of macular atrophy (MA) and choroidal neovascular membranes (CNVM). METHODS: A retrospective cohort study was conducted between January 2011 and March 2016. Demographic, clinical and imaging data from 26 consecutive AVL patients were analysed following case note review. Optical coherence tomography images were graded for SRDD and patients divided into those with/without SRDD. Outcomes included presenting/changes in best corrected visual acuity (BCVA) and incidence of MA/CNVM. RESULTS: Mean age was 78.6 ± 7.6 years. Mean follow-up was 51.5 ± 25.6 months. Twelve patients (46.2%) had SRDD at presentation with 3 more (11.5%) developing them. Subjects with SRDD were older (mean 81.7 ± 6.1 years vs 74.3 ± 7.6 years, p = 0.010). Mean presenting BCVA was worse in SRDD eyes (0.39 ± 0.31 logMAR vs 0.19 ± 0.18 logMAR, p = 0.017). Eight of 15 patients with SRDD (53.3%) developed incident MA or CNVM; higher than those with no SRDD (1/11, 9.1%; p = 0.036). Two patients (7.7%) developed full thickness macular holes. CONCLUSIONS: Patients with AVL and SRDD likely represent an advanced pathological stage or phenotype with worse visual outcome and higher risk of MA/CNVM. Possible overlap with AMD exists. Follow-up, counselling and provisions for early detection/treatment of complications should be made. Better classification including improved understanding of phenotypic and genetic variations with reference to comorbid diseases including AMD is required. Presence of SRDD in AVL offers a dichotomous classification, indicating risk of future MA/CNVM formation.

Expression of Toll-like receptors in human retinal and choroidal vascular endothelial cells.

Toll-like receptors (TLRs) are a family of proteins that initiate the innate immune response in reaction to invading microbes. Studies confirm the expression of TLRs in a variety of ocular tissues and cells, and it has also been suggested that selected TLRs may be associated with geographic atrophy and neovascularisation in age-related macular degeneration, diabetic retinopathy and other vascular and inflammatory diseases of the ocular posterior segment. However, TLR expression and localisation in the retinal and choroidal vasculature has not been defined. A better understanding of differential TLR expression in the choroid and retina, particularly in endothelial cells would improve our knowledge of vascular and inflammatory diseases in the posterior segment of the eye. In this study the gene (mRNA) expression of TLRs 1-10 was investigated using RT-PCR and comparative qPCR and the protein expression and localisation of selected TLRs (3, 4, 6 and 9) were examined using western blotting, flow cytometry and immunofluorescent staining. PCR showed gene expression of TLR1-6 and 9 in human choroidal endothelial cells (hCEC) and TLR2-6, 9 and 10 in human retinal endothelial cells (hREC). Western blotting detected TLR3, 4 and 9 proteins in both hCEC and hREC with higher levels in hCEC, whilst TLR6 protein was not detectable in either endothelial cell type. Flow cytometry detected all four TLRs (3, 4, 6 and 9) on the cell surface and intracellularly, TLR6 expression was detectable but low. The expression and localisation of TLR3, 4 and 9 were confirmed by immunofluorescent staining in endothelial cells and whole tissue sections and their functionality tested by expression of IL-6 (ELISA) in response to stimulation with specific TLR ligands. This study has, for the first time, identified the differential expression and localisation of TLRs in intraocular endothelial cells. This profiling will help inform our understanding of different retinal and choroidal vascular diseases, as well as the development of future treatments for intraocular vascular diseases.

Prevalence and Associations of Epiretinal Membranes in an Elderly English Population: The Bridlington Eye Assessment Project.

Purpose: To determine the prevalence and risk factors of epiretinal membranes (ERMs) in an adult English population. Methods: The Bridlington Eye Assessment Project is a population-based study of eye disease among residents aged 65 years or older. Comprehensive interviews and ophthalmic examinations were conducted to assess potential risk factors. Digital mydriatic nonstereoscopic 30° colour fundus photography (CFP) was performed. ERMs were classified as primary/idiopathic or secondary on the basis of findings from the ocular examination and the structured questionnaire. Logistic regression models were used to determine the independence of potential risk factors for idiopathic ERMs. Results: In a comprehensive screening of 3588 patients aged over 65, we identified an eye-based prevalence of ERMs of 4.26% and a subject-based prevalence of ERMs of 6.88%. The majority of these cases were idiopathic in nature (90.7%), while 9.3% were secondary ERMs; predominantly, there was a history of cataract surgery (43.5%). No significant correlation between idiopathic ERMs and factors such as age, gender, diabetes, hypertension, a history of stroke, or the presence of AMD was found. Conclusions: The prevalence of ERMs in an elderly English population and the proportion of idiopathic and secondary ERMs are similar to previous reports. However, in elderly patients aged over 65 years, age is not a risk factor for the presence of idiopathic ERMs. The presence of diabetes, hypertension, a history of stroke, and AMD of any grade was not associated with ERMs.

Retinal and Choroidal Thickness in an Indigenous Population from Ghana: Comparison with Individuals with European or African Ancestry.

Purpose: To evaluate the thickness of the macular retina and central choroid in an indigenous population from Ghana, Africa and to compare them with those measured among individuals with European or African ancestry. Design: Cross-sectional study, systematic review, and meta-analyses. Participants: Forty-two healthy Ghanaians, 37 healthy individuals with European ancestry, and an additional 1427 healthy subjects with African ancestry from previously published studies. Methods: Macular retinal thickness in the fovea, parafovea, and perifovea and central choroidal thickness were extracted from OCT volume scans. Associations with ethnicity, age, and sex were assessed using mixed-effect regression models. Monte Carlo simulations were performed to determine the sensitivity of significant associations to additional potential confounders. Pooled estimates of retinal thickness among other groups with African ancestry were generated through systematic review and meta-analyses. Main Outcome Measures: Macular retinal thickness and central choroidal thickness and their association with ethnicity, age, and sex. Results: When adjusted for age and sex, the macular retina and central choroid of Ghanaians are significantly thinner as compared with subjects with European ancestry (P < 0.001). A reduction in retinal and choroidal thickness is observed with age, although this effect is independent of ethnicity. Meta-analyses indicate that retinal thickness among Ghanaians differs markedly from that of African Americans and other previously reported indigenous African populations. Conclusions: The thickness of the retina among Ghanaians differs not only from those measured among individuals with European ancestry, but also from those obtained from African Americans. Normative retinal and choroidal parameters determined among individuals with African or European ancestry may not be sufficient to describe indigenous African populations. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Vitreomacular interface abnormalities in the Ghanaian African.

BACKGROUND/OBJECTIVE: Describe vitreomacular interface abnormalities (VMIA) using spectral-domain optical coherence tomography (SD-OCT), and correlations with age-related macular degeneration (AMD) grade in Ghanaian Africans. SUBJECTS/METHODS: Prospective, cross-sectional study of adults aged ≥50 years recruited in Ghana AMD Study. Participant demographics, medical histories, ophthalmic examination, digital colour fundus photography (CFP) were obtained. High-resolution five-line raster OCT, Macular Cube 512 × 128 scans, and additional line scans in areas of clinical abnormality, were acquired. SD-OCT VMI features classified by International Vitreomacular Traction Study Group system and relationships to AMD grade were evaluated. OUTCOMES: VMIA prevalence, posterior vitreous detachment (PVD), vitreomacular adhesions (VMA), vitreomacular traction (VMT), epiretinal membranes (ERM), correlations with AMD grade. RESULTS: The full Ghana AMD cohort included 718 participants; 624 participants (1248 eyes) aged ≥50 years (range = 50-101, mean = 68.8), 68.9% female were included in this analysis. CFP with OCT scans were available for 776 eyes (397 participants); 707 (91.1%) had gradable CFP and OCT scans for both AMD and VMI grading forming the dataset for this report. PVD was absent in 504 (71.3%); partial and complete PVD occurred in 16.7% and 12.0% respectively. PVD did not increase with age (p = 0.720). VMIA without traction and macular holes were observed in 12.2% of eyes; 87.8% had no abnormalities. VMIA was not significantly correlated with AMD grade (p = 0.819). CONCLUSIONS: This provides the first assessment of VMIA in Ghanaian Africans. VMIA are common in Africans; PVD may be less common than in Caucasians. There was no significant association of AMD grade with VMIA.

Faricimab: Transforming the Future of Macular Diseases Treatment - A Comprehensive Review of Clinical Studies.

Degenerative eye conditions such as age-related macular degeneration (AMD), diabetic retinopathy, and retinal vein occlusion are major contributors to significant vision loss in developed nations. The primary therapeutic approach for managing complications linked to these diseases involves the intravitreal delivery of anti-vascular endothelial growth factor (VEGF) treatments. Faricimab is a novel, humanised, bispecific antibody that simultaneously binds all VEGF-A isoforms and Angiopoietin-2, which has been approved by regulatory agencies, such as the US Food and Drug Administration (FDA), the UK Medicines and Healthcare products Regulatory Agency (MHRA) and the European Medicines Agency (EMA), for the treatment of neovascular AMD and diabetic macular oedema (DMO). Intravitreal faricimab holds the promise of reducing the treatment burden for patients with these conditions by achieving comparable or superior therapeutic outcomes with fewer clinic visits. The scope of faricimab's application includes addressing complex macular conditions such as DMO. This review intends to elucidate the distinctive pharmacological characteristics of faricimab and provide an overview of the key clinical trials and real-world studies that assess its effectiveness and safety in treating degenerative macular diseases.

A multi-centre investigation of macrovascular and non-ocular microvascular complications in children and adolescents with diabetes mellitus in southern Ghana.

Objectives: To investigate the prevalence of macrovascular and non-ocular microvascular complications and the associated factors among children and adolescents with diabetes mellitus in selected hospitals in southern Ghana. Design: A cross-sectional study. Setting: The out-patient clinics of the Departments of Child Health, Medicine and Therapeutics, Family Medicine, Ophthalmology, and the National Diabetes Management and Research Centre, all at the Korle Bu Teaching Hospital, Accra, as well as from Cape-Coast Teaching Hospital in the Central Region of Ghana. Participants: Fifty-eight children and adolescents aged 4-19 years who had been diagnosed with diabetes mellitus. Main outcome measures: Macrovascular (peripheral artery disease and coronary heart disease) and non-ocular microvascular complications (neuropathy and nephropathy). Results: Data from 58 children and adolescents with diabetes were analysed. The mean age of participants was 14.6±2.6 years, and a female preponderance was observed (45, 77.6%). The prevalence of macrovascular and non-ocular microvascular complications was 27.6% and 8.6%, respectively. Long duration of diabetes diagnosis (p=0.044) and low triglycerides (p=0.009) were associated with microvascular complications, while high triglycerides (p=0.032), lower HDL cholesterol (p=0.046), and abnormal body mass index (p=0.020) were associated with macrovascular complications. Conclusions: Macrovascular and non-ocular microvascular complications are common among children and adolescents with diabetes in southern Ghana and are associated with a long duration of diabetes diagnosis, abnormal body mass index, low HDL cholesterol, and triglyceride levels. Therefore, the early institution of regular screening for diabetes-related complications to allow early detection and appropriate management is recommended. Funding: University of Ghana Research Fund.

Visual evoked potential (VEP) and multifocal electroretinogram (mfERG) in ocular syphilitic posterior segment inflammation.

The aim of this study is to correlate multifocal electroretinogram (mfERG) and visual evoked potential (VEP) changes with visual acuity and clinical features in patients with posterior segment inflammation secondary to syphilis. A retrospective interventional case series of 4 patients with visual loss secondary to syphilitic uveitis is reported. The mfERG (P1) showed diminished amplitudes and prolonged latency in 7 affected eyes. Visual acuity rapidly improved 2 weeks after initiation of therapy. OCT demonstrated anatomical recovery at 1 month. In three patients, visual acuity was restored to 6/6 at 6-9 months but mfERG responses remained significantly reduced and delayed for 12-15 months before recovery to normal levels. One patient developed a retinal detachment, but achieved 6/9 vision at 30 months. VEP changes, interpreted in combination with mfERG responses, showed evidence of optic nerve involvement in 6 eyes. Ocular findings, including posterior placoid chorioretinitis, are important diagnostic features of secondary and tertiary syphilis. Visual acuity and clinical recovery occur early with appropriate diagnosis and treatment, and precede full electrophysiological recovery of the outer retina-RPE complex. Ophthalmologists have the opportunity to play a key role in undetected or missed diagnoses of syphilis, and with appropriate treatment the visual prognosis is excellent.

Use of ziv-aflibercept in diabetic macular edema in a Ghanaian population.

AIM: To investigate the use of intravitreal ziv-aflibercept (IVZ) in Ghanaian patients with diabetic macular edema (DME). METHODS: A retrospective study of patients with DME, who had been treated with IVZ (1.25 mg/0.05 ml), as part of routine clinical practice, on pro re nata basis between 2016 and 2018 who had a minimum follow-up of 6 months was retrieved and analyzed. The primary outcome measure was change in best-corrected visual acuity (BCVA) at 6 months. Secondary outcome measures are change in BCVA at 12 months and at the last follow-up visit, adverse events and change in central macular thickness (CMT). RESULTS: Twenty-five eyes of 17 patients (11 males) were included in this study. Their mean age was 60.82 ± 7.70 years and the mean duration of follow-up was 9.52 ± 3.31 months. The mean baseline BCVA (logMAR) of 0.65 ± 0.3 improved to 0.34 ± 0.16 (p < 0.0001) and 0.22 ± 0.15 (p = 0.0004) at 6 and 12 months, respectively. Twelve (48%) eyes had a visual gain of at least three lines at 6 months and 4 of 12 eyes (33.3%) at 1 year. There was a significant reduction in the mean CMT at 6 and 12 months and at the last follow-up visit compared to baseline (p < 0.0001). The adverse events recorded were raised intraocular pressure (four eyes) at 3, 6, and 12 months post injection, increased blood pressure in a patient with known systemic hypertension and transient memory loss in one patient. CONCLUSION: IVZ (1.25 mg) was associated with significant improvement in BCVA and reduction in CMT at 6 and 12 months in eyes with DME. A randomized clinical trial is warranted to assess this potentially cost-effective intervention for DME in low-resource settings.

Toll-Like Receptor Signalling Pathways and the Pathogenesis of Retinal Diseases.

There is growing evidence that the pathogenesis of retinal diseases such as diabetic retinopathy (DR) and age-related macular degeneration (AMD) have a significant chronic inflammatory component. A vital part of the inflammatory cascade is through the activation of pattern recognition receptors (PRR) such as toll-like receptors (TLR). Here, we reviewed the past and current literature to ascertain the cumulative knowledge regarding the effect of TLRs on the development and progression of retinal diseases. There is burgeoning research demonstrating the relationship between TLRs and risk of developing retinal diseases, utilising a range of relevant disease models and a few large clinical investigations. The literature confirms that TLRs are involved in the development and progression of retinal diseases such as DR, AMD, and ischaemic retinopathy. Genetic polymorphisms in TLRs appear to contribute to the risk of developing AMD and DR. However, there are some inconsistencies in the published reports which require further elucidation. The evidence regarding TLR associations in retinal dystrophies including retinitis pigmentosa is limited. Based on the current evidence relating to the role of TLRs, combining anti-VEGF therapies with TLR inhibition may provide a longer-lasting treatment in some retinal vascular diseases.

Prevalence of Reduced Vision among UK Elderly Drivers: The Bridlington Eye Assessment Project (BEAP)-A Cross-Sectional Study.

Self-assessment of driving fitness is mandatory in the United Kingdom. A paucity of data on visual function among drivers exists. We report prevalence of elderly drivers below legal visual acuity (VA) standard from a population study (The Bridlington Eye Assessment Project (BEAP)) conducted from 2002 to 2006. All residents aged ≥65 years were invited, 3459 undergoing structured interviews/ophthalmic examinations. Driving status was recorded, VA measured, and visual field (VF) testing performed. Outcomes were prevalence and characteristics of drivers below VA legal standard and prevalence of bilateral VF defects. Conditions causing reduced VA were explored and those with treatable conditions allowing visual improvement identified. Duration since last optometry review was recorded. Associations were explored using unpaired t-tests for continuous and chi-squared for discrete variables. Logistic regression was used for multivariate analysis and to determine odd ratios in the final adjusted model. Statistical analysis was performed using Stata 14.0 (Stata Corp, Tx). Within this sample, 7.1% (95% CI 6.0-8.3) of drivers fell below the VA legal driving standard (6/12) in their better eye, with 20% not having seen an optometrist for 2 years, including 8.2% who had not attended for over 5 years. The percentage of drivers falling below the VA minimum increases with age reaching 22.8% (95% CI 13.7-35.3) among those aged 85-89 years. 7.2% (95% CI 6.2-8.6) of drivers had bilateral visual field defects. 93% of drivers with reduced VA below legal standard had a cataract, refractive error or both in at least one eye. Significant numbers of elderly drive with VA below legal standard, most having easily correctable causes. Poor attendance with optometrists appears commonplace. Public education raised awareness of legal driving standards and encouraged compliance are required. Regular eye tests, appropriate refractive correction, and cataract surgery when needed should be encouraged.

A Cross-Sectional Study of Ocular Changes in Children and Adolescents with Diabetes Mellitus in Selected Health Facilities in Ghana.

BACKGROUND: The main objective of the study was to determine the prevalence of diabetic retinopathy (DR), other diabetes-related ocular changes (e.g., cataracts, corneal ulceration), and non-diabetic ocular disease in Ghanaian children and adolescents. The second objective was to evaluate the relationship between these conditions and age at diagnosis, current age, diabetes mellitus (DM) duration, and participant's sex. METHODS: A cross-sectional study, undertaken by a multidisciplinary team, included a cohort of children and adolescents (4-19 years) with DM recruited from selected health facilities in Ghana, from March 2016 to September 2019, after written informed consent or assent. The cohort will be followed up for 3 years to determine the natural course of the ocular changes, reported later. Participants were examined for all microvascular and macrovascular complications, non-diabetic ocular disease, anthropometric measurements, laboratory characteristics and quality of life issues. Full ocular examination was also undertaken. Statistical Package for Social Sciences (SPSS Version 25.0) was used for the data analysis. Continuous and categorical variables were presented as mean and standard deviation (SD), median (interquartile range) and as percentages (%), respectively. T-test and Mann-Whitney U test were used in establishing associations. RESULTS: A total of 58 participants were recruited. DR was detected in only 1 out of 58 (1.7%) participants at baseline. Cataracts were the most common ocular finding, detected in 42 (72%) at baseline. Other anterior segment changes observed included blepharitis 46 (79.3%) and tear film instability 38 (65.5%). There was a significant positive association between duration of the DM and the risk of cataract (p = 0.027). Participants' age at diagnosis was significantly associated with the presence of prominent corneal nerves (p = 0.004). CONCLUSIONS: DR was uncommon in this cohort of young persons with DM in Ghana. Cataracts, blepharitis and refractive errors were ocular changes commonly observed. All young persons with diabetes should undergo regular eye examination in all clinics where follow-up care is provided.

Characterization of West African Crystalline Macular Dystrophy in the Ghanaian Population.

OBJECTIVE: West African crystalline maculopathy (WACM) is characterized by the presence of macular hyperrefractile crystal-like deposits. Although the underlying pathophysiology has not been elucidated, a few biologic drivers have been proposed. We analyzed a large WACM case series to gain a more robust understanding of its features and etiology. DESIGN: Prospective, cross-sectional cohort study. SUBJECTS: Participants with WACM were selected from the large cohort recruited in the Ghana Age-Related Macular Degeneration Study. METHODS: Demographic and detailed medical histories, full ophthalmic examinations, digital color fundus photographs, and OCT images were obtained. All cases with WACM were evaluated by 3 retina experts. Crystal numbers, location, and distribution were determined. Associations between WACM and White age-related macular degeneration (AMD) risk variants were assessed using Firth's bias-reduced logistic regression, including age and sex as covariates. MAIN OUTCOME MEASURES: Phenotypic features of, and genetic associations with, WACM. RESULTS: West African crystalline maculopathy was identified in 106 eyes of 53 participants: 22 were bilateral and 24 were unilateral. Grading for AMD was not possible in 1 eye in 7 participants with WACM; therefore, laterality was not assessed in these subjects. Thirty-eight participants were women and were 14 men; sex was unrecorded for 1 participant. The mean age was 68.4 years (range, 45-101 years). Typical WACM crystals were demonstrated on OCT, which were more easily identified at high contrast and predominantly located at the inner limiting membrane. In eyes with copathology, crystals localized deeper in the inner retina, with wider retinal distribution over copathology lesions. There was no association with age or sex. A significant association was observed between the complement factor H (CFH) 402H risk variant and WACM. CONCLUSIONS: This study confirms the localization of crystals adjacent to the inner limiting membrane and distribution over lesions in eyes with copathology. The evaluation of OCT images under high contrast allows improved identification. West African crystalline maculopathy may be associated with the CFH-CFHR5 AMD risk locus identified among Whites; however, it is also possible that the combination of crystals and the CFH 402H allele increases the risk for developing late AMD. Further analyses using larger sample sizes are warranted to identify causalities between genotype and WACM phenotype.

Comparison of choroidal and retinal endothelial cells: characteristics and response to VEGF isoforms and anti-VEGF treatments.

Neovascular eye diseases such as wet age-related macular degeneration and proliferative diabetic retinopathy are two of the most common causes of irreversible visual loss. Although mediated by vascular endothelial growth factor (VEGF), the mechanisms of these diseases are not fully understood. Molecular inhibitors of VEGF including pegaptanib, ranibizumab and bevacizumab are used as treatments for these diseases. However, there have been very few direct comparisons between these agents, and as dose and treatment regimes differ their relative efficacies are hard to determine. In vitro comparisons tend to use cells from different sites or species, which show heterogeneity in their responses. The aim of this study was to compare the characteristics of primary cultures of isolated human choroidal endothelial cells (hCEC) and retinal endothelial cells (hREC), and their proliferation responses to stimulation with VEGF 121 and 165, and to compare the anti-proliferative effects of these three drugs. hCEC and hREC were positive for the cell markers VEGFR1, VEGFR2, CD31, CD34 and von Willebrand's factor (vWF), with greater expression of CD34 on the hREC compared to hCEC. Contrary to previous assumptions VEGF isoforms 121 and 165 were found to be equally potent in stimulating endothelial cell proliferation. However, hREC exhibited higher proliferation with either VEGF isoform compared to hCEC. The anti-VEGF treatments ranibizumab and bevacizumab were effective in decreasing proliferation of hCEC induced by the two VEGF isoforms, individually and in combination, with ranibizumab being moderately more effective, particularly in hREC. Pegaptanib was effective in controlling the proliferation of hCEC stimulated by VEGF 165, but was ineffective against the stimulatory effect of VEGF 121. There were found to be significant differences in microvascular endothelial cells from the retina and choroid, both in the expression of cell markers and their behaviour in response to growth factors and currently available anti-VEGF agents, highlighting the importance of targeting treatments to specific intraocular vascular beds and/or diseases.

Retrospective Analysis of Treatment Patterns in Pseudophakic Diabetic Macular Oedema Eyes Treated with Anti-VEGF.

METHODS: We performed a retrospective review of outcomes in 81 pseudophakic eyes with DMO that received at least 6 anti-VEGF injections. We reviewed baseline and posttreatment optical coherence tomography images, visual acuity, prescribing patterns, time taken to deliver anti-VEGF injections, and structural and functional outcomes. RESULTS: It took an average of 913 ± 454.1 days to deliver a mean of 11.1 ± 4.7 anti-VEGF injections. Time from baseline to receiving the first 6 anti-VEGF injections was longer than 9 months in 74.7% (n = 59/79) of eyes. There was a mean gain of 1.6 letters (-0.03 logMAR) from baseline to the end point. After 5 anti-VEGF intravitreal injections, the mean CMT was 391.9 µm from 474.4 µm at baseline (p < 0.0001). In 52 of 79 eyes (65.8%), more than one type of anti-VEGF agent was used. CONCLUSIONS: The anti-VEGF treatment used to treat these eyes with DMO was suboptimal, a finding consistent with recently published "real-world" data. There was a strong tendency for patients to be switched within the class to a second anti-VEGF agent.

The efficacy of biofeedback visual rehabilitation therapy in patients with infantile nystagmus syndrome: A retrospective study.

OBJECTIVE: To report fixation stability changes in patients with different forms of infantile nystagmus syndrome (INS), who have undergone a visual rehabilitation through biofeedback fixation training (BFT) with microperimetry (MP). DESIGN: Retrospective study. METHODS: Patients 6 to 12 years-old with INS who performed BFT with MP. Initially 10 once-weekly followed by eight twice-weekly sessions of BFT during a minimum of 6 months period were performed. Visual acuity (VA) and MP fixation stability indices were analyzed, including displacement from fixation point (P1, P2) and percentage of retinal loci used during fixation attempt (BCEA 63% and 95%). Statistical analysis was conducted at baseline (BL), 10 weeks (W10) and 6 months (M6). RESULTS: Twelve patients (mean age 8.9 years.) with INS completed the whole training session. All patients showed significant improvement in the mean BCEA fixation area (deg2): For BCEA@95% BL was 78.0, 46.1 at W10, and 27.4 at M6 (p-value = 0.004). For BCEA@63% BL was 27.3, 15.4 in W10, and 9.17 at M6 (p = 0.01). The ANOVA test for the FS indices of P1 and P2, as well as for BCVA showed no significant difference when compared at the same intervals. CONCLUSION: Fixation stability (FS) indices of BCEAs (63% and 95%) improved at W10 and M6, while P1 and P2 showed significant improvement at W10 but not at M6, probably because BCEA involves a much larger area than P1 and P2. VA did not show significant improvement at any time point.

In vivo confocal microscopy features and clinicohistological correlation of limbal nerve corpuscles.

AIMS: To describe the in vivo confocal microscopy (IVCM) features of human limbal nerve corpuscles (LNCs) and correlate these with the histological features. METHODS: We examined 40 eyes of 29 healthy living subjects (17 female, 12 male; mean age=47.6) by IVCM. Four limbal quadrants were scanned through all epithelial layers and stroma to identify the LNCs and associated nerves. Ten fresh normal human corneoscleral discs from five deceased patients with a mean age of 67 years and 17 eye-bank corneoscleral rims with a mean age of 57.6 years were stained as whole mounts by the acetylcholinesterase (AChE) method to demonstrate LNCs and corneal nerves. Stained tissue was scanned in multiple layers with the NanoZoomer digital pathology microscope. The in vivo results were correlated to the histological findings. RESULTS: On IVCM, LNCs were identified in 65% of the eyes studied and were mainly (84%) located in the inferior or superior limbal regions. They appeared either as bright (hyper-reflective) round or oval single structures within the hyporeflective, relatively acellular fibrous core of the palisades or were clustered in groups, often located anterior to the palisades of Vogt. They measured 36 µm in largest diameter (range 20-56 µm). The in vivo features were consistent with the histology, which showed LNCs as strongly AChE positive round or oval structures. CONCLUSION: The strong correlation with histology will enable use of IVCM to study LNCs in normal and disease conditions.

Characteristics of Geographic atrophy in an elderly UK population-The Bridlington Eye Assessment Project (BEAP): a cross-sectional study (2002-2006).

BACKGROUND/OBJECTIVES: Geographic atrophy (GA) is a common cause of visual loss. The UK population prevalence is unknown. We studied GA prevalence, characteristics, and associations in an elderly UK population. METHODS: Masked grading of colour fundus photographs from 3549 participants in the cross-sectional study of Bridlington residents aged ≥65 years. GA size, shape and foveal involvement were correlated with demography and vision. RESULTS: GA was detected in 130 eyes (101 individuals) of 3480 participants with gradable images (prevalence 2.90%; 95% CI 2.39-3.52 either eye), was bilateral in 29/3252 subjects (0.89%, 95% CI 0.62-1.28) with bilateral gradable photos, with mean age of 79.26 years (SD 6.99, range 67-96). Prevalence increased with age, from 1.29% (95% CI 0.69-2.33) at 65-69 to 11.96% (95% CI 7.97-17.50) at 85-90 years. Mean GA area was 4.51 mm2 (SD 6.48, 95% CI 3.35-5.66); lesions were multifocal in 47/130 eyes (36.2%; 95% CI 28.4-44.7). Foveal involvement occurred in 41/130 eyes (31.5%; 95% CI 24.2-40.0). In eccentric GA, mean distance from circumference to fovea was 671µm (SD 463; 95% CI 570-773). Older age (OR 1.10/year increase; 95% CI 1.06-1.14), RPD (OR 1.87; 95% CI 1.10-3.19) and large drusen/RPD ≥ 125 µm (OR 6.16; 95% CI 3.51-10.75) were significantly associated with GA in multivariate analysis. GA lesions (18/31 eyes; 58%; 95% CI 40.7-73.6) had U-shape configuration more frequently in RPD subjects than those without (9/99 eyes, 9.1%; 95% CI 4.66-16.6) (p = 0.0001). CONCLUSION: GA, commonly solitary and eccentric, occurred in the perifovea. However, one third of GA eyes had foveal and bilateral involvement. Possible association of RPD with GA phenotype exists. Population multimodal imaging studies may improve understanding further.