It is not an infectious disease, yet type 2 diabetes is so widespread – and what’s more, its spread is so growing – that it looks like a real epidemic. Mainly linked to an incorrect style of view, his cases are added to those of type 1 diabetes, bringing with them all the risks of an out-of-control blood sugar.
These also include eye complications. Here, in fact, diabetes can cause dangerous alterations in blood circulation.
Under attack a precise structure of the retina: the macula, the most central area and most sensitive to light stimuli. The consequences can be very serious. Diabetic retinopathy and age-related macular degeneration are in fact the main causes of blindness associated with retinal problems.
Better not to underestimate the problem
Diabetic macular edema is a fairly frequent manifestation of diabetic retinopathy. It mainly affects people who suffer from long-standing diabetes and those who have poor glycometabolic control.
In fact, hyperglycemia can alter the small blood vessels that supply the retina in the long run, a complex phenomenon that also involves inflammation and neurodegeneration for the retina itself.
Diabetic retinopathy is the leading cause of work-age visual loss in industrialized countries and is more common in type 1 diabetics. And its most serious complication is precisely diabetic macular edema.
To cause it is an accumulation of fluid that occurs in the macula: this happens because the small blood vessels, in the presence of diabetic retinopathy, are more permeable, so they let liquids through.
Alarm bells should never be underestimated: it usually manifests itself with characteristic symptoms, such as blurred and deformed vision. All this makes it difficult to perform any daily activity that requires separate vision, such as reading, writing or driving the car.
What is it
Diabetic macular edema is an accumulation of fluid in the macula, the central part of the retina, the most sensitive to light and which allows a fine view of the details. Fluids that accumulate leak out of the blood vessels of the retina, causing the macula to swell.
There are two types. Focal edema, localized only in certain places of the retina, is associated with problems with individual blood vessels. Diffuse edema is characterized by a generalized loss of fluid by many of the capillaries of the retina.
Sometimes the liquid creeps between the different layers of the macula, moving them apart. In these situations, numerous cysts can form, leading to “cystoid” macular edema.
Causes
Diabetic macular edema is a complication of diabetic retinopathy. The latter is in turn a complication of diabetes.
In the long term, abnormal blood sugar levels can in fact compromise the proper functioning of blood vessels, leading to oxygen deficiencies that stimulate the production of growth factors such as VEGF (vascular endothelial growth factor), which stimulates the production of new vessels and increases vascular permeability.
Not only that, oxygen deficiency leads to a reduction in the number of cells in the vessel wall, which results in greater permeability.
This phenomenon can occur in both type 1 diabetes and type 2 diabetes and is the most common cause of vision loss in those with these diseases. Its onset is usually earlier in type 2 diabetes and the incidence increases as the severity of retinopathy increases.
Common symptoms
Diabetic macular edema manifests itself with symptoms such as: blurred and deformed vision and altered color perception. All this makes it difficult to perform any daily activity that requires separate vision, such as reading, writing or driving the car.
Complications
If not treated properly diabetic macular edema can lead to severe vision loss in the central part of the visual field that makes daily activities such as reading or distinguishing faces difficult. In severe cases, blindness can occur.
Treatment
Often the first choice treatment is laser photocoagulation, which, however, generally does not allow to recover the already lost vision. For this reason, the use of laser is generally associated or replaced by pharmacological treatment based on intravitreal injections of anti-angiogenic drugs directed against VEGF (anti-VEGF drugs: pegaptanib, ranibizumab, aflibercept), which together with intravitreal implants (which allow the prolonged release of steroid drugs in the eye) allow a recovery of vision and not only stabilization.
Among the anti-VEGF, aflibercept is the most recently marketed. In addition to being a broad-spectrum anti-angiogenic (blocks and captures all VEGF isoforms), it is also able to modulate PIGF, (placental growth factor) that contributes to the inflammatory pathological mechanisms of increased permeability involved in the formation of macular edema.
After the “attack” phase, which consists of five injections on a monthly basis, effective results can be achieved with aflibercept with injections given every two months. And this is a considerable advantage for the patient.
Moreover, like all drugs used intravitreal in the treatment of diabetic macular edema, it is able to slow down the progression of other manifestations of retinopathy.
More rare, however, is the use of surgical treatment, which can be useful when the edema is not only associated with a problem of circulation but also of mechanical traction exerted by the vitreous (the gelatinous substance that fills the back of the eye) on the macula.
When to consult your doctor
The most effective weapon against macular edema is prevention. For this reason, those living with diabetes, in addition to keeping blood sugar under control as much as possible, should also undergo regular eye examinations, remembering to report any problems such as blurred vision, difficulty in seeing fine details, reading, alteration of color vision at each check.
In this way diabetic retinopathy and diabetic macular edema can be diagnosed and treated as soon as possible.
Joycelyn Elders is the author and creator of EmpowerEssence, a health and wellness blog. Elders is a respected public health advocate and pediatrician dedicated to promoting general health and well-being.
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