Optic nerve assessment is important for many blinding diseases, with cup-to-disc ratio (CDR) assessments commonly used in both diagnosis and progression monitoring of glaucoma patients. Optic disc, cup, rim area and CDR measurements all show substantial variation between human populations and high heritability estimates within populations. To identify loci underlying these quantitative traits, we performed a genome-wide association study in two Australian twin cohorts and identified rs3858145, P = 6.2 × 10−10, near the ATOH7 gene as associated with the mean disc area. ATOH7 is known from studies in model organisms to play a key role in retinal ganglion cell formation. The association with rs3858145 was replicated in a cohort of UK twins, with a meta-analysis of the combined data yielding P = 3.4 × 10−10. Imputation further increased the evidence for association for several SNPs in and around ATOH7 (P = 1.3 × 10−10 to 4.3 × 10−11, top SNP rs1900004). The meta-analysis also provided suggestive evidence for association for the cup area at rs690037, P = 1.5 × 10−7, in the gene RFTN1. Direct sequencing of ATOH7 in 12 patients with optic nerve hypoplasia, one of the leading causes of blindness in children, revealed two novel non-synonymous mutations (Arg65Gly, Ala47Thr) which were not found in 90 unrelated controls (combined Fisher's exact P = 0.0136). Furthermore, the Arg65Gly variant was found to have very low frequency (0.00066) in an additional set of 672 controls.

Ocular angiogenesis and macular oedema are major causes of sight loss across the world. Aberrant neovascularisation, which may arise secondary to numerous disease processes, can result in reduced vision as a result of oedema, haemorrhage, and scarring. The development of antivascular endothelial growth factor (anti-VEGF) agents has revolutionised the treatment of retinal vasogenic conditions. These drugs are now commonly employed for the treatment of a plethora of ocular pathologies including choroidal neovascularisation, diabetic macular oedema, and retinal vein occlusion to name a few. In this paper, we will explore the current use of anti-VEGF in a variety of retinal diseases and the impact that these medications have had on visual outcome for patients.

Abstract:Proliferative diabetic retinopathy (PDR) is a condition that carries a high risk of severe visual impairment. The hallmark of PDR is the growth of abnormal new vessels. In this paper, an automated method for the detection of new vessels from retinal images is presented. This method is based on a dual classification approach. Two vessel segmentation approaches are applied to create two separate binary vessel map which each hold vital information. Local morphology features are measured from each binary vessel map to produce two separate 4-D feature vectors. Independent classification is performed for each feature vector using a support vector machine (SVM) classifier. The system then combines these individual outcomes to produce a final decision. This is followed by the creation of additional features to generate 21-D feature vectors, which feed into a genetic algorithm based feature selection approach with the objective of finding feature subsets that improve the performance of the classification. Sensitivity and specificity results using a dataset of 60 images are 0.9138 and 0.9600 respectively on a per patch basis and 1.000 and 0.975 respectively on a per image basis.

address:Roshan.Welikala@kingston.ac.uk (R.A. Welikala). Abstract:Proliferative diabetic retinopathy (PDR) is a condition that carries a high risk of severe visual impairment. The hallmark of PDR is neovascularisation, the growth of abnormal new vessels. This paper describes an automated method for the detection of new vessels in retinal images.Two vessel segmentation approaches are applied, using the standard line operator and a novel modified line operator. The latter is designed to reduce false responses to non-vessel edges.Both generated binary vessel maps hold vital information which must be processed separately. This is achieved with a dual classification system. Local morphology features are measured from each binary vessel map to produce two separate feature sets. Independent classification © 2014, Elsevier. Licensed under the Creative Commons Attribution-NonCommercialNoDerivatives 4.0 International http://creativecommons.org/licenses/by-nc-nd/4.0/ is performed for each feature set using a support vector machine (SVM) classifier. The system then combines these individual classification outcomes to produce a final decision. Sensitivity and specificity results using a dataset of 60 images are 0.862 and 0.944 respectively on a per patch basis and 1.00 and 0.90 respectively on a per image basis.

IntroductionDiabetic macular edema (DME) is an important cause of vision loss. England has a national systematic photographic retinal screening programme to identify patients with diabetic eye disease. Grading retinal photographs according to this national protocol identifies surrogate markers for DME. We audited a care pathway using a spectral-domain optical coherence tomography (SDOCT) clinic to identify macular pathology in this subset of patients.MethodsA prospective audit was performed of patients referred from screening with mild to moderate non-proliferative diabetic retinopathy (R1) and surrogate markers for diabetic macular edema (M1) attending an SDOCT clinic. The SDOCT images were graded by an ophthalmologist as SDOCT positive, borderline or negative. SDOCT positive patients were referred to the medical retina clinic. SDOCT negative and borderline patients were further reviewed in the SDOCT clinic in 6 months.ResultsFrom a registered screening population of 17 551 patients with diabetes mellitus, 311 patients met the inclusion criteria between (March 2008 and September 2009). We analyzed images from 311 patients’ SDOCT clinic episodes. There were 131 SDOCT negative and 12 borderline patients booked for revisit in the OCT clinic. Twenty-four were referred back to photographic screening for a variety of reasons. A total of 144 were referred to ophthalmology with OCT evidence of definite macular pathology requiring review by an ophthalmologist.DiscussionThis analysis shows that patients with diabetes, mild to moderate non-proliferative diabetic retinopathy (R1) and evidence of diabetic maculopathy on non-stereoscopic retinal photographs (M1) have a 42.1% chance of having no macular edema on SDOCT imaging as defined by standard OCT definitions of DME when graded by a retinal specialist. SDOCT imaging is a useful adjunct to colour fundus photography in screening for referable diabetic maculopathy in our screening population.

Peripapillary choroidal neovascular membranes (PCNM) are defined as a collection of new choroidal blood vessels, any portion of which lies within one disc diameter of the nerve head. There are two types of PCNM, and correct pre-interventional identification of growth site has been shown to stratify the chance of visual improvement following therapy. Clinical manifestations occur only where the membrane extends over the macula, if the vessels haemorrhage into the subretinal space or fluid exudation occurs within the macula. This review provides an update and overview on the diverse range of current treatment studies and strategies being used in present clinical ophthalmic practice.

BCLs do not increase the likelihood of complete resolution when compared with OLs in the initial management of RCES. However, BCL treatment seems safe, and some patients experience earlier relief from symptoms.

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