Artificial intelligence within ophthalmologic diseases

As ophthalmology is an increasingly busy medical specialty relying solidly on imaging technology, this review investigates the introduction of artificial intelligence to improve diagnostic performance and reduce human resources. In diabetic retinopathy screening, algorithms are now regulatory-approved for international markets but not yet tailored for the Danish system. In age-related macular degeneration, algorithms are now able to facilitate the classification and segmentation of disease activity, and in upcoming years, these are likely to assist us to improve diagnosis and provide subsequent clinical care

Correlation between Retinal Vessel Calibre and Neurodegeneration in Patients with Type 2 Diabetes Mellitus in the European Consortium for the Early Treatment of Diabetic Retinopathy (EUROCONDOR)

&lt;b&gt;&lt;i&gt;Purpose:&lt;/i&gt;&lt;/b&gt; To investigate the correlation between retinal vessel calibre and measurements of neurodegeneration in patients with type 2 diabetes (T2D) and no or early diabetic retinopathy (DR). &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; Baseline data on 440 patients with T2D from the EUROCONDOR clinical trial were used. DR was graded according to the Early Treatment of Diabetic Retinopathy Study (ETDRS) scale, and patients with ETDRS levels 10-35 were included. Retinal vessel diameters were measured by semi-automatic software. Calibres were summarized into central retinal artery and vein equivalents (CRAE and CRVE). &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; Median age and diabetes duration were 64.0 and 10.3 years, respectively. ETDRS levels were 10 (42.3%), 20 (27.5%) and 35 (30.2%). The median CRAE and CRVE were 146.7 and 215.3 µm, respectively. CRAE did not differ according to ETRDS level (p = 0.12), but wider CRVE were found in patients with higher ETDRS levels (p = 0.04). In a multivariable linear regression model, CRAE was associated with macular ganglion cell layer thickness (coefficient 0.27 per micrometre, p &lt; 0.01), and CRVE was correlated with macular retinal thickness (coefficient -0.07 per micrometre, p = 0.04) and retinal nerve fibre layer thickness at the optic disc (coefficient 0.32 per micrometre, p &lt; 0.01). &lt;b&gt;&lt;i&gt;Conclusion:&lt;/i&gt;&lt;/b&gt; Retinal vessel calibre was independently associated with structural changes of the neuroretina in patients with no or early DR.</jats:p

Ophthalmol Ther

There is little understanding of long-term treatment persistence in patients receiving anti-vascular endothelial growth factor (anti-VEGF) injections for diabetic macular edema (DME), particularly relating to treatment intervals. The aim of this study was to investigate the association between treatment interval and discontinuation rate after 24 months of unilateral anti-VEGF treatment in patients with DME under routine clinical care in the USA. This was a non-interventional, retrospective cohort study to review the health insurance claims of adults with DME linked with the IBM MarketScan Commercial and Medicare Supplemental databases, who were continuously enrolled in a health plan for at least 6 months prior to their first anti-VEGF treatment and for a duration of at least 24 months between July 2011 and June 2017. Patients were grouped on the basis of the injection interval they achieved at 24 months of treatment. Discontinuation rate beyond 24 months and its association with treatment intervals at 24 months was estimated using the Kaplan-Meier method and Cox proportional hazards models. The overall discontinuation rate among the 1702 eligible patients from 24 to 60 months after treatment initiation was 30%. At 60 months, patients were more likely to remain on treatment in shorter (75.3% [4-week interval group]) versus longer treatment interval groups (62.1% [> 12-week interval group], difference = 13.2%, [95% confidence interval (CI) 1.06, 2.06], p = 0.01). Patients on a > 12-week interval were twice as likely to discontinue treatment compared with those on an 8-week interval (hazard ratio = 2.01 [95% CI 1.43, 2.82], p < 0.001). Patients with DME on longer anti-VEGF treatment intervals at 24 months consistently had higher discontinuation rates in the following years than those on shorter treatment intervals

Dexamethasone Intravitreal Implant Is Active at the Molecular Level Eight Weeks after Implantation in Experimental Central Retinal Vein Occlusion

Central retinal vein occlusion (CRVO) is a visually disabling condition resulting from a thrombus in the major outflow vessel of the eye. The inflammatory response in CRVO is effectively treated with a dexamethasone (DEX) intravitreal implant. Uncovering the proteome changes following DEX implant intervention in CRVO may identify key proteins that mediate the beneficial effects of DEX. In six G&ouml;ttingen minipigs, CRVO was induced in both eyes with an argon laser using a well-established experimental model. The right eyes were treated with a DEX intravitreal implant (Ozurdex, Allergan), while the left control eyes received a sham injection. Eight weeks after DEX intervention, retinal samples were collected and analyzed with tandem mass tag-based mass spectrometry. DEX implant intervention resulted in the upregulation of peptidyl-prolyl cis&ndash;trans isomerase FKBP5 (FKBP5) and ubiquilin-4. Immunohistochemistry showed expression of FKBP5 in the nuclei in all cellular layers of the retina. Cell adhesion molecule 3, tumor necrosis factor receptor superfamily member 16, and trans-1,2-dihydrobenzene-1,2-diol dehydrogenase were downregulated following DEX intervention. The upregulation of the corticosteroid-sensitive protein FKBP5 suggests that the implant remained active at the molecular level after eight weeks of treatment. Future studies may investigate if FKBP5 regulates the efficacy and duration of the DEX implant

Retinal vascular fractals predict long-term microvascular complications in type 1 diabetes mellitus:the Danish Cohort of Pediatric Diabetes 1987 (DCPD1987)

Diabetic neuropathy, nephropathy, and retinopathy cause significant morbidity in patients with type 1 diabetes, even though improvements in treatment modalities delay the appearance and reduce the severity of these complications. To prevent or further delay the onset, it is necessary to better understand common underlying pathogenesis and to discover preclinical biomarkers of these complications. Retinal vessel calibers have been associated with the presence of microvascular complications, but their long-term predictive value has only been sparsely investigated. We examined retinal vessel calibers as 16-year predictors of diabetic nephropathy, neuropathy, and proliferative retinopathy in a young population-based Danish cohort with type 1 diabetes. We used semiautomated computer software to analyze vessel diameters on baseline retinal photos. Calibers of all vessels coursing through a zone 0.5–1 disc diameter from the disc margin were measured and summarized as the central artery and vein equivalents. In multiple regression analyses, we found wider venular diameters and smaller arteriolar diameters were both predictive of the 16-year development of nephropathy, neuropathy, and proliferative retinopathy. Early retinal vessel caliber changes are seemingly early markers of microvascular processes, precede the development of microvascular complications, and are a potential noninvasive predictive test on future risk of diabetic retinopathy, neuropathy, and nephropathy.</jats:p

Proteome Analysis of Aflibercept Intervention in Experimental Central Retinal Vein Occlusion

Aflibercept is a frequently used inhibitor of vascular endothelial growth factor (VEGF) in the treatment of macular edema following central retinal vein occlusion (CRVO). Retinal proteome changes following aflibercept intervention in CRVO remain largely unstudied. Studying proteomic changes of aflibercept intervention may generate a better understanding of mechanisms of action and uncover aspects related to the safety profile. In 10 Danish Landrace pigs, CRVO was induced in both eyes with an argon laser. Right eyes were treated with intravitreal aflibercept while left control eyes received isotonic saline water. Retinal samples were collected 15 days after induced CRVO. Proteomic analysis by tandem mass tag-based mass spectrometry identified a total of 21 proteins that were changed in content following aflibercept intervention. In retinas treated with aflibercept, high levels of aflibercept components were reached, including the VEGF receptor-1 and VEGF receptor-2 domains. Fold changes in the additional proteins ranged between 0.70 and 1.19. Aflibercept intervention resulted in a downregulation of pigment epithelium-derived factor (PEDF) (fold change = 0.84) and endoplasmin (fold change = 0.91). The changes were slight and could thereby not be confirmed with less precise immunohistochemistry and Western blotting. Our data suggest that aflibercept had a narrow mechanism of action in the CRVO model. This may be an important observation in cases when macular edema secondary to CRVO is resistant to aflibercept intervention