Review and comparison of retinal vessel calibre and geometry software and their application to diabetes, cardiovascular disease, and dementia.

Developments in retinal imaging technologies have enabled the quantitative evaluation of the retinal vasculature. Changes in retinal calibre and/or geometry have been reported in systemic vascular diseases, including diabetes mellitus (DM), cardiovascular disease (CVD), and more recently in neurodegenerative diseases, such as dementia. Several retinal vessel analysis softwares exist, some being disease-specific, others for a broader context. In the research setting, retinal vasculature analysis using semi-automated software has identified associations between retinal vessel calibre and geometry and the presence of or risk of DM and its chronic complications, and of CVD and dementia, including in the general population. In this article, we review and compare the most widely used semi-automated retinal vessel analysis softwares and their associations with ocular imaging findings in common systemic diseases, including DM and its chronic complications, CVD, and dementia. We also provide original data comparing retinal calibre grading in people with Type 1 DM using two softwares, with good concordance.

A digital online platform for education and certification of diabetic retinopathy health care professionals in the Region of Southern Denmark.

PURPOSE: The incidence of diabetes continues to increase across the world. As the number of patients rises, so does the need for educated health care professionals. Diabetic retinopathy (DR) remains one of the primary complications in diabetes, and screening has proved to be a cost-effective measure to avoid DR-related blindness. Denmark has an established screening programme, but no formal training of the people responsible for analysing retinal images. METHODS: We here present an online learning platform that offers a diabetic eye screening course for health care professionals undertaking screening responsibility in the Region of Southern Denmark. The course is divided into lectures, each focussed on identifying different levels of DR or detecting related lesions. The course is free to use on-demand, contains instructional videos, interactive tests and exercises, and it is concluded with a certification test. The tools on the platform can in addition be used to generate data for research purposes, such as comparing users or experts in detection of lesions or annotating data for the development of machine learning models. RESULTS: More than 150 participants have so far completed the course, and the platform is being adopted for education in other regions of Denmark.

Comparison of different methods of retinal imaging for the screening of diabetic retinopathy: a systematic review.

BACKGROUND: Screening for diabetic retinopathy (DR) is recommended to detect sight-threatening complications prior to visual loss. Early Treatment Diabetic Retinopathy Study (ETDRS) seven standard field (7SF) retinal imaging has traditionally been regarded the gold standard for DR classification, but other methods are often preferred clinically. The purpose of this systematic review was to determine whether 7SF is the most optimal screening method for DR grading, or if similar results can be achieved by other methods using a smaller field of view (<7SF) or ultra-wide field (UWF) imaging. METHODS: Based on Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, two independent reviewers initially identified 7167 publications in PubMed, Cochrane and Embase databases. Of these, 16 publications were included based on predefined inclusion criteria. RESULTS: 7SF was used as reference standard in 12 studies (compared with < 7SF in five studies and UWF in seven studies), and four studies compared other reference standards. Compared to 7SF, studies using < 7SF and UWF images both reported of similar agreement. A lower rate of ungradable images was reported for mydriatic and non-mydriatic UWF as compared to non-mydriatic < 7SF modalities. CONCLUSION: Retinal imaging of <7SF and UWF both provide acceptable performance compared to 7SF. Given the time-consuming nature of the latter, these methods could be reasonable options in DR screening, even though a high number of ungradable images in non-mydriatic < 7SF may pose a clinical challenge.

Risk of eye diseases in osteogenesis imperfecta - A nationwide, register-based cohort study.

BACKGROUND: Osteogenesis imperfecta (OI) is a hereditary disease caused by affected collagen type 1. Collagen type 1 is an important structural component of the eye. Ocular manifestations in OI are described in literature, but little is known about the risk of eye diseases in OI. OBJECTIVE: To investigate the risk of eye diseases in OI. DESIGN: A Danish nationwide register-based cohort study based on data from the Danish National Patient Register. PARTICIPANTS: All patients registered with an OI diagnosis between January 1977 and December 2018 matched 1:5 with a reference population on gender and birth month and birth year. MEASUREMENTS: Incidence rates (IR) per 1000 patient years and sub-hazard ratio (SHR) for any eye disease, corneal diseases, cataract, refraction disorders, vitreous haemorrhage, retinal detachment, retinopathy, angiopathy, retinal haemorrhage, retinal degeneration, retinal changes, optic nerve disorders, and traumatic eye lesions. RESULTS: We identified 907 OI patients (493 women) and 4535 persons (2465 women) in the reference population. The IR for any eye disease was 4.07 [95% CI 3.41-4.85] in the OI cohort and 1.96 [95% CI 1.89-2.12] in the reference cohort. The two diseases with highest incidence was cataract (2.41 [95%CI 1.93-3.03] vs 1.29 [95% CI 1.12-1.47], SHR 1.76 [95% CI 1.34-2.33]) and glaucoma (1.08 [95% CI 0.77-1.51] vs 0.42 [95% CI 0.33-0.54], SHR 2.33 [95% CI 1.55-3.53]). The absolute risk of most other eye diseases was low, but the SHR indicated a higher risk in the OI cohort compared to the reference group showing statistically increased risk of refractive disorders, vitreous haemorrhage, retinal detachment or ruptures, other retinal diseases (i.e., retinopathy, angiopathy, retinal haemorrhage, degeneration, retinal changes), and optic nerve disorders. Corneal diseases and traumatic eye lesions were not statistically significantly increased in OI-patients. CONCLUSION: Patients with OI have a higher risk of cataract, refractive disorders, glaucoma, vitreous haemorrhages, retinal detachment/ruptures, retinal diseases, and optic nerve disorders.

Noninvasive Retinal Markers in Diabetic Retinopathy: Advancing from Bench towards Bedside.

The retinal vascular system is the only part of the human body available for direct, in vivo inspection. Noninvasive retinal markers are important to identity patients in risk of sight-threatening diabetic retinopathy. Studies have correlated structural features like retinal vascular caliber and fractals with micro- and macrovascular dysfunction in diabetes. Likewise, the retinal metabolism can be evaluated by retinal oximetry, and higher retinal venular oxygen saturation has been demonstrated in patients with diabetic retinopathy. So far, most studies have been cross-sectional, but these can only disclose associations and are not able to separate cause from effect or to establish the predictive value of retinal vascular dysfunction with respect to long-term complications. Likewise, retinal markers have not been investigated as markers of treatment outcome in patients with proliferative diabetic retinopathy and diabetic macular edema. The Department of Ophthalmology at Odense University Hospital, Denmark, has a strong tradition of studying the retinal microvasculature in diabetic retinopathy. In the present paper, we demonstrate the importance of the retinal vasculature not only as predictors of long-term microvasculopathy but also as markers of treatment outcome in sight-threatening diabetic retinopathy in well-established population-based cohorts of patients with diabetes.

The 16-year incidence, progression and regression of diabetic retinopathy in a young population-based Danish cohort with type 1 diabetes mellitus: The Danish cohort of pediatric diabetes 1987 (DCPD1987).

The aim was to investigate the long-term incidence of proliferative diabetic retinopathy (PDR), and progression and regression of diabetic retinopathy (DR) and associated risk factors in young Danish patients with Type 1 diabetes mellitus. In 1987-89, a pediatric cohort involving approximately 75 % of all children with Type 1 diabetes in Denmark <19 years of age was identified (n = 720). In 1995, 339 (47.1 %) were re-studied with retinopathy graded and all relevant diabetic parameters assessed. Of those, 185 (54.6 %) were evaluated again in 2011 for the same clinical parameters. All retinal images were graded using modified early treatment of DR study for 1995 and 2011. In 1995, mean age was 21.0 years and mean diabetes duration 13.5 years. The 16-year incidence of proliferative retinopathy, 2-step progression and 2-step regression of DR was 31.0, 64.4 and 0.0 %, respectively, while the incidence of DR was 95.1 %. In a multivariate logistic regression model, progression to PDR was significantly associated with 1995 HbA1c (OR 2.61 per 1 % increase, 95 % CI 1.85-3.68) and 1995 diastolic blood pressure (OR 1.79 per 10 mmHg increase, 95 % CI 1.04-3.07). Two-step progression of DR was associated with male gender (OR 2.37 vs. female, 95 % CI 1.07-5.27), 1995 HbA1c (OR 3.02 per 1 % increase, 95 % CI 2.04-4.48) and 1995 vibration perception threshold (OR 1.19 per 1 Volt increase, 95 % CI 1.02-1.40). In conclusion, one in three progressed to PDR and two in three had 2-step progression despite young age and increased awareness of the importance of metabolic control. After 30 years duration of diabetes, the presence of DR is almost universal.