Fundamental principles of an effective diabetic retinopathy screening program

Background: Diabetic retinopathy (DR) is the leading cause of blindness among working-age adults worldwide. Early detection and treatment are necessary to forestall vision loss from DR. Methods: A working group of ophthalmic and diabetes experts was established to develop a consensus on the key principles of an effective DR screening program. Recommendations are based on analysis of a structured literature review. Results: The recommendations for implementing an effective DR screening program are: (1) Examination methods must be suitable for the screening region, and DR classification/grading systems must be systematic and uniformly applied. Two-field retinal imaging is sufficient for DR screening and is preferable to seven-field imaging, and referable DR should be well defined and reliably identifiable by qualified screening staff; (2) in many countries/regions, screening can and should take place outside the ophthalmology clinic; (3) screening staff should be accredited and show evidence of ongoing training; (4) screening programs should adhere to relevant national quality assurance standards; (5) studies that use uniform definitions of risk to determine optimum risk-based screening intervals are required; (6) technology infrastructure should be in place to ensure that high-quality images can be stored securely to protect patient information; (7) although screening for diabetic macular edema (DME) in conjunction with DR evaluations may have merit, there is currently insufficient evidence to support implementation of programs solely for DME screening. Conclusion: Use of these recommendations may yield more effective DR screening programs that reduce the risk of vision loss worldwide

Diabetic retinopathy in type 1 diabetes mellitus. A study on medical risk indicators and treatment outcome.

Diabetic retinopathy is a common complication to diabetes mellitus and is still a major cause of impaired vision in the Western world. The aim of the present study was to identify medical risk factors influencing the development and progression of retinopathy in type 1 diabetic patients, and to investigate the effects of laser treatment on visual acuity and glare. Although the development of sight-threatening retinopathy during a 10-year follow-up period was 37%, less than 1% of the patients became blind (VA£0.1). The development of retinopathy was associated with hyperglycemia and to some extent, a high blood pressure. In patients followed from the onset of the disease, no patient developed sight-threatening retinopathy during the first 10 years. Pregnancy per se did not seem to be a risk factor for progression of retinopathy but preeclampsia during pregnancy was. Although nephropathy and severe retinopathy are closely associated, we identified a subgroup of patients with proliferative retinopathy who did not develop any signs of nephropathy during 10 years of follow-up. Homocysteine did not seem to be an independent risk factor for retinopathy. Patients treated with photocoagulation for clinically significant macular edema had few complications and a good visual outcome. Despite a good visual outcome, many patients with panretinal photocoagulation for proliferative retinopathy express problems with glare. We could confirm their symptoms by demonstrating a prolonged visual recovery time during glare exposure. Thus, patients with type 1 diabetes mellitus who develop sight-threatening retinopathy can expect a good visual outcome due to early detection and photocoagulation treatment. Hyperglycemia and to some extent high blood pressure are risk factors for its development

Three-year follow-up of visual outcome and quality of life in patients with age-related macular degeneration

Background: The purpose of this study was to evaluate the visual outcome and self-reported vision-targeted health status in patients treated with intravitreal ranibizumab for wet age-related macular degeneration (AMD). Methods: A total of 51 eyes from 50 patients aged 76 ± 7 years, with wet AMD not previously treated, were included in this prospective study. Best corrected visual acuity was examined using Early Treatment Diabetic Research Study charts and near vision reading. All patients underwent an ophthalmological examination, including fluorescein and indocyanine green angiography (occult cases) and optical coherence tomography. The Visual Function Questionnaire test was completed before and 37 ± 7 months after the start of intravitreal injections. Results: The patients received a mean number of 7.8 ± 5.0 (range 2-22) injections. One month after the third intravitreal injection, significant improvement was seen in both visual acuity (53 ± 14 to 61 ± 14 letter, P = 0.001) and near vision (17 ± 9 to 11 ± 8 points, P = 0.001). During follow-up, mean visual acuity decreased from 53 ± 14 to 44 ± 24 letters (P = 0.011), and near vision decreased from 17 ± 9 to 20 ± 11 points (P = 0.048). Despite visual impairment, the quality of life test revealed no significant decrease in mental health (P = 0.529) or ability to read a newspaper (P = 0.21), but a decrease in distance activities (reading street signs, steps, going to the theater) from 57 ± 27 to 46 ± 31 points (P = 0.007) was documented. Conclusion: Decreased visual acuity was related to a decrease in self-reported visual function for distance activities, while mental health items, such as worrying, were not influenced

Multifocal electroretinography amplitudes increase after photocoagulation in areas with increased retinal thickness and hard exudates.

Abstract. Purpose: This study aimed to evaluate local response on multifocal electroretinography (mfERG) and to assess retinal thickness with optical coherence tomography (OCT) after focal laser treatment in areas with retinal oedema and exudates in patients with diabetic retinopathy. Methods: Twelve diabetes patients (aged 60 +/- 14 years, diabetes duration 16 +/- 8 years) treated with focal or grid photocoagulation in areas with retinal oedema and/or exudates underwent mfERG and OCT before and 3 months after treatment. The average thickness (in mum) in any of the nine sectors (defined according to the ETDRS) treated with photocoagulation was measured. Amplitudes and implicit times were analysed in corresponding areas on the mfERG. Results: Mean mfERG amplitudes increased after photocoagulation (21.5 +/- 8.0 nV/deg(2) versus 16.8 +/- 6.1 nV/deg(2); p = 0.012), whereas no difference was seen in implicit times. Mean OCT values in the treated regions were lower at follow-up (272 +/- 23 mum versus 327 +/- 79 mum; p = 0.013). No correlation was seen between changes in mfERG response and changes in OCT values. The decrease in retinal thickness was correlated with the number of laser spots applied (p = 0.002). Conclusions: Focal argon laser treatment is effective in reducing retinal thickness. In addition, treated areas tend to show improved retinal function as demonstrated by increased amplitudes on mfERG

Photocoagulation of diabetic macular oedema--complications and visual outcome

PURPOSE: To describe complications and visual outcome of photocoagulation for clinically significant macular oedema. SUBJECTS AND METHODS: Evaluation of macular oedema and complications of photocoagulation in 194 eyes, defined as subretinal fibrosis, atrophic creep of the pigment epithelium and subretinal neovascularization was based on stereo fundus photo grading. The study included 25 patients with type 1 and 93 patients with type 2 diabetes (age 32 +/- 10 and 65 +/- 9 years, respectively). The statistical evaluations were based on one eye per patient. RESULTS: Follow-up time was 5.5 +/- 2.4 years (mean +/- SD). Complications within 1/3 ODD from the centre of the macula were seen in 4% (1/23) of eyes of patients with type 1 diabetes, compared to 26% (20/76) of eyes among patients with type 2 diabetes (p=0.02). Hard exsudates before treatment were more common in type 2 than in type 1 diabetic eyes, 70/82 vs. 11/23 (p<0.001). In all eyes, hard exsudates were more often associated with subretinal fibrosis or atrophic creep (35/133 eyes) than diffuse oedema (5/44 eyes) (p=0.04). CONCLUSION: Photocoagulation for clinically significant macular oedema with hard exudates, particularly when subfoveally located, was more often associated with subretinal fibrosis or atrophic creep of the pigment epithelium than photocoagulation of oedema without hard exudates. Hard exudates as well as complications after photocoagulation were more common in type 2 than in type 1 diabetes, resulting in poorer visual outcome in this group of patients

No improvement in injection frequency or in visual outcome over time in two cohorts of patients from the same swedish county treated for wet age-related macular degeneration

Background: Although ranibizumab has been used for the treatment of wet age-related macular degeneration (AMD) since 2007, real-world studies still report undertreatment resulting in a less favorable visual outcome. In this study, two different time cohorts of patients treated with ranibizumab for wet AMD in routine care were analyzed to observe whether there was a change over time regarding visual outcome, injection frequency, and quality of life (QoL). Methods: We compared patients with treatment-naïve wet AMD in two observational follow-up cohorts 2007–2010 (n=50 patients) and 2009–2013 (n=26). After a loading dose of three intravitreal ranibizumab injections, the patients were treated under the pro re nata regimen. Visual acuity (VA) was examined by Early Treatment Diabetic Retinopathy Study (ETDRS) charts. The National Eye Institute Visual Functioning Questionnaire 25 was answered by patients at baseline and at 37±7 months (cohort 1) and at 45±4 months (cohort 2). Results: At baseline, the cohorts were homogeneous considering mean age (76±7 vs 75±8 years), mean VA (53±14 vs 52±15 ETDRS letters), and mean self-reported symptom duration (14±11 vs 13±11 weeks). Mean VA decreased in both cohorts over time, from 53±14 to 45±24 letters (P=0.011) and from 52±15 to 46±22 letters (P=0.175), respectively. The patients received a mean of 8±5 and 9±7 injections, respectively. The mean composite score change from baseline to follow-up decreased in cohort 1 from 64±21 to 59±25 scores (P=0.04) but increased in cohort 2 from 64±28 to 67±23 scores (P=0.38). Conclusion: We could not demonstrate any improvement in the number of injections in two different time cohorts of patients treated with ranibizumab for wet AMD in a Swedish county. Visual outcomes decreased after 3 years of follow-up, but QoL scores were divergent

Using multifocal electroretinography hard exudates affect macular function in eyes with diabetic retinopathy

To evaluate the influence of hard exudates on macular function in patients with diabetic retinopathy. METHODS: Thirty seven eyes from 27 diabetic patients, aged 57 +/- 14 years, diabetes duration 12.5 +/- 9 years, not previously treated with photocoagulation, underwent fundus photography, multifocal electroretinography (mfERG) and optical coherence tomography (OCT). Hard exudates were graded from fundus photography with superimposed OCT and a superimposed hexagonal pattern (mfERG) by one retinal specialist, unaware of mfERG and OCT results. We defined three groups; A = eyes with exudates in the analyzed zone, B = eyes with no exudates in the analyzed zone but elsewhere, and C = eyes with no exudates. The mfERG responses and OCT values from five defined areas in the macula were compared. RESULTS: MfERG showed that the implicit time was significantly prolonged in group A compared to group C in the central, middle and outer areas and in the nasal and temporal area (p = 0.045, 0.019, 0.017 and 0.035 and 0.016 respectively), in group B compared to group C in the central area (p = 0.016), and in group A compared to group B in the outer area (p = 0.035). Amplitude differed between group A and C in the middle area and outer area (14.2 +/- 5.2 nV/deg(2) vs 21.1 +/- 8.7 nV/deg(2), p = 0.037 and 14.1 +/- 3.9 nV/deg(2) vs 17.7 +/- 7.1 nV/deg(2) , p = 0.02 respectively), and between group B and C in the temporal area 14.5 +/- 2.2 nV/deg(2) vs 20.0 +/- 8.7 nV/deg(2), p = 0.017). Macular thickness assessed with OCT was similar between the groups. CONCLUSIONS: In eyes with diabetic retinopathy, hard exudates prolong the implicit time assessed with mfERG, compared to eyes without hard exudates, and independently of macular thickness. These results indicate that the hard exudates in the macular region, even at a distance from the fovea centre, have a deleterious effect on macular function