The effects of diabetes mellitus on the eyes

One of the most important complications of sugaryness occurs in and may seriously affect diabetic vision. “According to surveys, one out of every ten people on our planet suffers from diabetes mellitus. One in four patients with type 2 diabetes will experience eye damage due to high body sugar concentration. Of these, 50% are not aware of his problem, as he is not subject to regular ophthalmological control”, notes Mr Pantelis Papadopoulos Coordinator Director of Ophthalmologist I Ophthalmological Clinic Metropolitan Hospital. Diabetic retinopathy “The diabetic retinopathy”, continues “is one of the most serious events that occur in the eyes due to diabetes mellitus and is distinguished in two types: • Nonproductive retinopathy: This form may occur in a mild, moderate or severe degree. In this type, small retinal vessels are initially affected. As the disease develops, capillaries are blocked, causing ischaemia, while the larger vessels gain damage to their walls, causing microhaemorrhages, microarrhages and extremities, which may lead to a decrease in vision due to fluid accumulation in the macular area. In this case we have the diabetic macular oedema. • Productive retinopathy: In this type, due to extensive ischaemia abnormal vessels, known as neovasculars, appear. If not treated in time, these neovasculars may cause a sharp decrease in vision due to bleeding, ulcerative retinal detachment or even an increase in intraocular pressure (neovascular glaucoma)”. What factors are associated with the occurrence of diabetic retinopathy? The development of diabetic retinopathy is associated with the following factors: • Duration of diabetes mellitus • Unfulfilled regulation of hyperglycaemia (HbA1c > 6.5%) • Hypertension • Smoking • Hypercholesterolaemia • Hyperlipidaemia • Protein • Pregnancy/pregnancy What are the symptoms of diabetic retinopathy? “In the early stages of the disease, no signs of vision are observed. Even when there are serious retinal changes, due to nonproductive retinopathy, the patient may not perceive any symptoms that will lead him to the doctor, because he does not feel any pain or affect his vision, Mr Papadopoulos says and adds: “The first symptoms of visual decrease will occur when it is affected or pale spot, the central area of the retina, i.e. where the most important photo-hypods are located. Diabetic macular oedema is due to fluid accumulation from the leaking vessels. In this case the decrease in vision occurs progressively and over a long period of time. But if an endovolbic hemorrhage occurs due to neovascularisation, then the fall of vision will be sharp. In case of neovascular glaucoma, the reduction in vision may also be accompanied by pain. However, it is worth noting that ‘even in advanced cases, the disease can develop for a long time without symptoms, stressing the need for regular ophthalmological monitoring for people with diabetes. Patients with diabetes mellitus should be examined once a year if they do not have signs of diabetic retinopathy. If signs occur, monitoring should be done more frequently, depending on the severity of retinopathy,” he adds. How is diabetic retinopathy diagnosed? The best protection against diabetic retinopathy is regular eye tests. According to the American Academy of Ophthalmology, the recommended frequency of control for patients with diabetes mellitus is defined as follows: • For patients with type I diabetes mellitus, each year after 5 years of diagnosis. • For patients with type II diabetes mellitus, immediately after diagnosis and after each year. • For pregnant women with diabetes mellitus, testing is recommended during the first trimester of pregnancy. Annual ophthalmologic testing helps to diagnose the diabetic eye disease immediately and includes various tests such as: • Visual acuity check • Examination in the fissile lamp: The presence of cataract and neovascularization of the iris is controlled. • Tonometry: Measurement of intraocular pressure for glaucoma. • Depth: Examination of the bottom of the eye for detection of signs, such as microaques, extremities, neovasculars, vitreous bleeding, retinal detachment and optic nerve lesions. • Fluoroangiography: Examination by intravenous contrast for diagnosis of ischemia or leakage of retinal vessels. • OCT (Coherence Visual Tomography) macular: 3D imaging of retinal layers in real time. • OCT Angio (Visible Angio) macular: Displaying the hair and vascular network with bloodless angiography, without infusion of intravenous contrast. • Colour bottom photos: Recording with digital bottom camera for detailed analysis of retinal anatomy. • Colour photos of extended field of view (wide field): Detailed representation of retinal anatomy. Who are more vulnerable to the development of diabetic retinopathy? “usually, the first signs of diabetes in the eye appear in the majority of individuals with insulin-dependent diabetes (type I) about 10 to 15 years after diagnosis of the disease. In subjects with type 2 diabetes developed at an older age, they are usually detected during ophthalmological examination. The time of the occurrence of diabetic changes depends directly on glucose control. If patients adjust glycosylated haemoglobin (HbA1c) below 6.5%, they will likely never have diabetic retinopathy. In patients with impaired blood sugar, the first signs appear after a decade. In addition, genetic factors appear to affect the extent to which the disease affects the eye, while in children suffering from juvenile diabetes, diabetic alterations usually occur during puberty” the expert explains. When should the diabetic patient have ophthalmological examinations? ‘ Patients suffering from diabetes mellitus should undergo annual examinations if they do not show signs of diabetic retinopathy. If they experience diabetic retinopathy or start insulin therapy, tests should be performed every 4-6 months, or more frequently, as instructed by the ophthalmologist. In each diabetic patient, a complete ophthalmological examination, including dredging should initially be performed. In addition, OCT is necessary for detailed control of the bottom, especially in subjects with initial or possible diabetic retinopathy. At the same time, digital photography of the bottom at regular intervals helps the ophthalmologist detect minor differences in the bottom image. If there are changes affecting vision, the condition of the bottom vessels should also be considered using fluoroangiography. This examination is performed after intravenous pigment infusion and depicts the pathological signs in the vessels and swelling caused by them. In many cases, this is necessary for laser therapy,” he notes. How is diabetic retinopathy treated? “The best approach to treating the disease is to regulate diabetes”, he stresses. “The therapeutic approach varies according to the type and severity of diabetic retinopathy, with the ophthalmologist choosing the appropriate approach for each patient” continues, quoting the therapeutic methods: • Photocoagulation with Argon Laser: This is a focal photocoagulation that uses Laser to cauterize bleeding retinal vessels, with the aim of stabilizing vision and reducing extremities. • Intra-vital infusions of anti-VEGF agents: Anti-angiogenetic drugs are used to combat pathological neovascularisation and retinal oedema. • Hyloidectomy or vitreectomy: It is a microsurgery that involves removing the hyaloid body, especially in cases of retinal bleeding or detachment. • Valve injection in case of neovascular glaucoma: It’s an anti-glaucoma operation to reduce intraocular pressure. “These treatments are applied according to the stage of the disease and can stabilize or even improve the vision of patients suffering from diabetic retinopathy, macular oedema and other related conditions,” concludes Mr Papadopoulos.