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

Sight-threatening retinopathy is associated with lower mortality in type 2 diabetic subjects: A 10-year observation study.

Aims: To study associations between diabetic retinopathy and development of stroke, myocardial infarction and death in type 2 diabetic patients. Methods: During a 10-year observation period, 363 type 2 diabetic patients (diagnosis >= 30 years of age) attending an outpatient clinic were studied regarding the prevalence and incidence of retinopathy and associated risk factors, i.e., (HbA(1c), blood pressure, albuminuria, plasma creatinine, age, sex and diabetes duration) in relation to the development of myocardial infarction, stroke and death. The degree of retinopathy was classified as no retinopathy, background or sight-threatening retinopathy, i.e., clinically significant macular edema, severe non-proliferative or proliferative retinopathy. Results: During the study period, 62 patients had had myocardial infarction, 54 stroke and 99 patients died. Patients with sight-threatening retinopathy at baseline (n = 41) had a 2.2-fold increased (p < 0.01) risk for death compared to patients with no or background retinopathy, even when controlled for medical risk factors. When adjusted for medical risk factors, patients with no retinopathy at baseline (n = 226) who remained without retinopathy or developed background retinopathy (n = 187) during the study period, had a 3.6-fold increased risk for death (95% CI, 1.1, 11.8), (p = 0.03), compared to patients who developed sight-threatening retinopathy (n = 39), while the incidence of myocardial infarction did not differ. More patients who developed sight-threatening retinopathy were treated with ACE inhibitors than patients who did not (41% versus 24%; p = 0.03). Conclusion: Despite more medical risk factors, patients who developed sight-threatening retinopathy had lower mortality compared to patients with no or background retinopathy at follow-up. More patients who developed sight-threatening retinopathy were treated with ACE inhibitors but this seemed not to have influenced the lower mortality rate in this group, whereas the use of ACE inhibitors in patients who did not develop sight-threatening retinopathy was connected with lower mortality rate

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

In diabetic eyes, multifocal ERG reflects differences in function between the nasal part and the temporal part of the macula.

PURPOSE: The purpose of the present study was to compare retinal function between the perifoveal nasal and perifoveal temporal areas of diabetic eyes using multifocalERG (mfERG). METHODS: We included 36 eyes from 27 patients with diabetes (age 58 ± 14 years; duration of diabetes 13 ± 9 years; HbA(1c) 7.1 ± 1.8%) and a control group with 18 eyes from 18 healthy subjects (age 57 ± 11 years). Retinal thickness was assessed with optical coherence tomography (OCT) in the perifoveal areas corresponding to the summed nasal and temporal inner and outer areas. MfERG amplitude and implicit time were recorded from corresponding areas. RESULTS: Diabetic eyes showed lower mfERG amplitude in the nasal area than in the temporal area (14 ± 6 vs 17 ± 7 nV/deg(2); p < 0.0001) and longer implicit time (31 ± 3 vs 30 ± 3 ms; p = 0.005). In the control group, there were no significant differences between the two areas. CONCLUSION: Diabetic eyes showed lower amplitude and longer implicit time in the nasal area than in the temporal, which might indicate that the nasal area is more vulnerable. These findings may be of importance for evaluation of diabetic maculopathy and outcome after laser treatment