Diabetic retinopathy - ocular complications of diabetes mellitus

Abstract

In industrialized nations diabetic retinopathy is the most frequent microvascular complication of diabetes mellitus and the most common cause of blindness in the working-age population. In the next 15 years, the number of patients suffering from diabetes mellitus is expected to increase significantly. By the year 2030, about 440 million people in the age-group 20-79 years are estimated to be suffering from diabetes mellitus worldwide (prevalence 7.7%), while in 2010 there were 285 million people with diabetes mellitus (prevalence 6.4%). This accounts for an increase in patients with diabetes in industrialized nations by 20% and in developing countries by 69% until the year 2030. Due to the expected rise in diabetic patients, the need for ophthalmic care of patients (i.e., exams and treatments) will also increase and represents a challenge for eye-care providers. Development of optimized screening programs, which respect available resources of the ophthalmic infrastructure, will become even more important. Main reasons for loss of vision in patients with diabetes mellitus are diabetic macular edema and proliferative diabetic retinopathy. Incidence or progression of these potentially blinding complications can be greatly reduced by adequate control of blood glucose and blood pressure levels. Additionally, regular ophthalmic exams are mandatory for detecting ocular complications and initiating treatments such as laser photocoagulation in case of clinical significant diabetic macular edema or early proliferative diabetic retinopathy. In this way, the risk of blindness can considerably be reduced. In advanced stages of diabetic retinopathy, pars-plana vitrectomy is performed to treat vitreous hemorrhage and tractional retinal detachment. In recent years, the advent of intravitreal medication has improved therapeutic options for patients with advanced diabetic macular edema.

Keywords: Diabetic macular edema; Diabetic retinopathy; Intravitreal injection; Laser photocoagulation; Prevention.

Figure 1

Non-proliferative diabetic retinopathy. Wide-field fundus photo of a 65-year-old female patient (right eye) showing several retinal hemorrhages.

Figure 2

Non-proliferative diabetic retinopathy. Color fundus photo of a 51-year-old male patient with micro-aneurysms and lipid exudates.

Figure 3

Proliferative diabetic retinopathy with neovascularization at disk.

Figure 4

Advanced proliferative diabetic retinopathy with neovascularization and limited vitreous hemorrhage.

Figure 5

Advanced proliferative diabetic retinopathy with tractional retinal detachment.

Figure 6

Neovascularization of the iris. These neovascular vessels may block the trabecular meshwork and cause neovascular glaucoma.

Figure 7

Clinically significant diabetic macular edema without involvement of the fovea. A: Fundus photo; B: Fluorescein angiogram depicting leakage of perifoveal retinal blood vessels.

Figure 8

Center-involving diabetic macular edema with subfoveal edema and numerous lipid exudates.

Figure 9

Fluorescein angiogram of a 49-year-old female patient. A: Fluorescein angiogram of the right eye 50 s after intravenous injection of fluorescein dye. Here, leaking micro-aneurysms in the macula can be seen; B: Fluorescein angiogram of the left eye 25 s after intravenous injection of fluorescein dye. Leakage from neovascular blood vessels causes spots of increased fluorescence at the optic disk and temporal to the fovea; C: Fluorescein angiogram of the temporal part of the left eye 30 s after intravenous injection of fluorescein dye. Areas of retinal non-perfusion can be seen as reason for neovascularization.

Figure 10

Wide-field picture of the right eye of a 65-year-old female patient. A: On scanning-laser-ophthalmoscope-Imaging some micro-aneurysms and lipid exudates can be seen; B: Fluorescein angiogram shows leakage from micro-aneurysms and extensive areas of retinal non-perfusion.

Figure 11

Spectral-domain optical coherence tomography of a female patient with center-involving diabetic macular edema. On the left side of the picture, an infra-red image shows the exact location of the OCT-scan on the right. The OCT-scan visualizes intraretinal edema with thickening of the fovea. OCT: Optical coherence tomography.

Figure 12

Color fundus photo of a 53-year-old male patient several months after focal laser photocoagulation because of clinical significant diabetic macular edema. While the laser scars and some remaining dot-hemorrhages are visible, lipid exudates and retinal edema have disappeared.

Figure 13

Wide-field picture of the right eye of a 48-year-old male patient after pan-retinal laser photocoagulation because of proliferative diabetic retinopathy. The peripheral laser scars can be seen in the picture, while neovascularization have regressed.

Figure 14

Proliferative diabetic retinopathy with extensive fibro-vascular membranes.