Biomarkers of Diabetic Retinopathy.

Diabetic retinopathy (DR), a leading cause of acquired vision loss, is a microvascular complication of diabetes. While traditional risk factors for diabetic retinopathy including longer duration of diabetes, poor blood glucose control, and dyslipidemia are helpful in stratifying patient's risk for developing retinopathy, many patients without these traditional risk factors develop DR; furthermore, there are persons with long diabetes duration who do not develop DR. Thus, identifying biomarkers to predict DR or to determine therapeutic response is important. A biomarker can be defined as a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacologic responses to a therapeutic intervention. Incorporation of biomarkers into risk stratification of persons with diabetes would likely aid in early diagnosis and guide treatment methods for those with DR or with worsening DR. Systemic biomarkers of DR include serum measures including genomic, proteomic, and metabolomics biomarkers. Ocular biomarkers including tears and vitreous and retinal vascular structural changes have also been studied extensively to prognosticate the risk of DR development. The current studies on biomarkers are limited by the need for larger sample sizes, cross-validation in different populations and ethnic groups, and time-efficient and cost-effective analytical techniques. Future research is important to explore novel DR biomarkers that are non-invasive, rapid, economical, and accurate to help reduce the incidence and progression of DR in people with diabetes.

Improving the rates of electronic results acknowledgement at a tertiary eye care centre.

BACKGROUND: Hundreds of thousands of tests are performed annually in hospitals worldwide. Safety Issues arise when abnormal results are not recognized promptly resulting in delayed treatment and increased morbidity and mortality. As a result Singapore's largest healthcare group, Singhealth introduced an electronic result acknowledgement system. This system was adopted by the Singapore National Eye Centre (SNEC) in February 2016. Baseline measurements show that weekly numbers of unacknowledged results ranged from 193 to 617. The current standards of electronic results acknowledgement posts a significant patient safety hazard. METHODS: Root cause analysis was performed to identify contributory factors. Pareto principle was then used by the authors to identify the main contributory factors. We employed the rapid cycle improvement Plan-do-study-act (PDSA) strategy to test and evaluate implemented changes. Changes are implemented for 2 weeks and data collected prospectively. The data is analyzed the week after and the following PDSA actions are decided and instituted the following week. 3 PDSA cycles were undertaken in total. RESULTS: The first PDSA cycle focused on raising awareness of the problem at hand, the number of unacknowledged results drastically decreased during the 1stweek of implementation of our PDSA from 617 to 254. The second PDSA cycle targeted the lack of knowledge of doctors involved in the electronic result acknowledgement process. There was a trend downwards near the end of the cycle which continued through the week after. The third PDSA cycle targeted individual doctors and provided individual remedial training. Second line doctors were also equipped to better handle abnormal results. There was significant improvement with the number of unacknowledged abnormal results dropping to <5 a week. CONCLUSIONS: Multiple factors were identified to contribute to the low compliance to electronic acknowledgement of results. The role doctors play in the issue at hand was paramount and required careful handling in a professional manner with multiple reminders and emphasis on the importance of acknowledging and acting on the results.A significant improvement in the rates of acknowledgement of abnormal results was demonstrated with clear benefits to patient safety. Interventions can be replicated when implementing similar systems to other areas of healthcare.

Is Choroidal or Scleral Thickness Related to Myopic Macular Degeneration?

Purpose: The relative contribution of mechanical and vascular factors to the pathogenesis of myopic macular degeneration (MMD) is unclear. To address this gap, we examined the association of choroidal thickness (CT) and scleral thickness (ST) with MMD. Methods: Prospective, clinic-based case series of 62 eyes of 41 patients with high myopia (≤-6 diopters or axial length ≥26.5 mm). Swept-source optical coherence tomography (SSOCT) was performed to measure subfoveal CT and ST. Myopic macular degeneration was graded from fundus photographs according to the International Meta-Analysis for Pathologic Myopia (META-PM) classification. Presence of MMD was defined as META-PM category ≥ 2 and severe MMD was defined as category ≥ 3. Results: The distribution of MMD severity was 15 (24.2%) in category 1, 28 (45.2%) in category 2, 10 (16.1%) in category 3, and 9 (14.5%) in category 4. Correlation of MMD severity was strong for subfoveal CT (r = -0.70, P < 0.001) but weak for subfoveal ST (r = -0.31, P = 0.01). Subfoveal CT, but not ST, was independently associated with presence of MMD (age and gender adjusted odds ratio [OR] per 10 µm decrease in CT 1.41, P = 0.002), and subfoveal CT, but not subfoveal ST, was significantly thinner in eyes with severe MMD (≥ category 3) than in eyes with mild MMD (CT: 31.5 ± 40.5 µm versus 82.0 ± 57.1 µm, P < 0.001; ST: 261.6 ± 78.5 µm versus 297.0 ± 73.8 µm, P = 0.09). Conclusions: We demonstrated significant thinning of the choroid with increasing MMD severity. In contrast, ST was weakly correlated with MMD. These data suggest progressive loss of choroid may be important in the pathogenesis of MMD.

A Prospective Study of Biometric Stability After Scleral Buckling Surgery.

PURPOSE: To assess time to stabilization and factors associated with changes in biometric parameters after scleral buckling (SB). DESIGN: Prospective case series. METHODS: Seventeen eyes with primary rhegmatogenous retinal detachment (RRD) that underwent SB at the Singapore National Eye Centre were enrolled. SB surgery was performed using an encircling element and segmental buckle. Axial length (AL); anterior chamber depth (ACD), defined as the distance from the corneal epithelium to the anterior lens surface; anterior/posterior corneal curvature (K); and refraction were measured preoperatively and at week 1 and months 1, 3, 6, 9, and 12 postoperatively. Stability of each parameter was defined as the earliest time point at which there is no significant difference compared to its value at month 12. RESULTS: AL increased (26.09 ± 1.46 to 26.51 ± 1.96, P = .01), ACD decreased (3.84 ± 0.47 to 3.32 ± 0.57, P < .001), and a myopic shift of 1.04 diopters (95% CI 0.03-2.05, P = .04) occurred at month 12. Anterior/posterior K were not significantly changed from baseline. AL stabilized at month 3 while ACD and spherical equivalent (SE) stabilized at week 1. Cryotherapy was associated with greater increase in AL (P = .001) and myopic shift (P = .02). More extensive segmental buckling was associated with greater increase in AL (P = .009) and myopic shift (P = .03). CONCLUSIONS: Our study suggests that patients requiring cataract surgery after SB should have biometry performed no earlier than 3 months post SB surgery, and intraocular lens power calculation with a fourth-generation formula. A greater increase in AL and myopic shift was associated with cryotherapy and more extensive segmental buckling.