Diabetes Mellitus is a disease in which the body reduces the ability to store and use sugar. High levels of blood sugar, excessive thirst with increased urine, and changes in the blood vessels of the body are the characteristics of this disease. Besides diabetes can cause serious disturbances in the eyes, cataracts, glaucoma, and occasional blurred vision, changes in the blood vessels of the microcirculation of the eye, are some of the changes that occur in diabetic patients.
WHAT IS DIABETIC RETINOPATHY?
Diabetic retinopathy is an ophthalmic complication of diabetes. It is caused by deterioration of the blood vessels that feed the retina at the back of the eye. This weakening of blood vessels may cause dilation of the vessel wall causing leakage of fluids such as plasma or blood. The end result is the appearance of retinal edema and hemorrhages.
The retina is the part of the eye which focuses light coming from outside. The light or focused images are sent to the brain by the optic nerve. When plasma or blood spills damage the retina, the image generated is anomalous and the vision becomes blurred.
The risk of developing diabetic retinopathy is high in patients suffering from diabetes for a period of time, several years. About 60% of patients with diabetes for 15 years or more, have alterations in the blood vessels in your eyes. When diabetes develops in childhood or youth is called juvenile diabetes. Young Diabetics are more likely to develop diabetic retinopathy at younger ages. However, only a small percentage of these retinopathies has serious vision, and a smaller percentage can lead to blindness.
Diabetic retinopathy is the leading cause of blindness in adults in Western countries, and patients with diabetes are 25 times more prone to blindness than people without diabetes.
There are two forms of diabetic retinopathy. First, retinopathy subclinical, that occurs in the involvement of small retinal vessels. Some get smaller vessels and others increase and form pockets which obstruct the flow of blood causing extravasation of blood plasma and subsequently. These hemorrhages and effusions of blood vessels in the retina can cause deposits called exudates.
Subclinical retinopathy is considered an early stage of diabetic retinopathy. Fortunately the view is not seriously affected and usually remains stationary, without progress, in 80% of cases. In some cases, however, spilled fluids accumulate in the macula, the central part of the retina responsible for central vision, the most important visual field. The direct images, reading and close work may deteriorate, and loss of central vision can end in blindness. Subclinical retinopathy is a warning sign and may progress to a progressive and irreversible deterioration of vision.
Second is proliferative retinopathy. This occurs as a continuation of the previous form, with the addition of new blood vessels to grow on the surface of the retina or optic nerve. These new blood vessels are very fragile and can rupture and bleed into the vitreous. If the flow of blood is plentiful stain the transparent vitreous, interfering the passage of light. The result will be loss of vision. In addition the scar tissue formed from the mass caused by the rupture of blood vessels in the vitreous can drag and stretch the retina causing a loosening of the same in the posterior pole of the eye. The blood vessels may grow in the iris and cause a typical form of secondary glaucoma. Severe loss of vision or even blindness may be the end result of this process.
CAUSES AND SYMPTOMS
Cause of diabetic retinopathy is not completely solved, however, it is known that diabetes weakens the small blood vessels in different body areas. Pregnancy and high blood pressure can worsen this condition in diabetic patients.
Although it can occur in a progressive loss of vision, is not affected in the initial subclinical forms, so it is necessary to perform regular eye exams to diabetic patients to prevent the progression of retinal destructive process.
When bleeding occurs in proliferative retinopathy, patients have a complete loss of vision. Although there are no symptoms of pain, this acute form of diabetic retinopathy requires immediate medical attention.
DETECTION AND DIAGNOSIS
A complete eye exam by an eye doctor is the best protection against the progression of diabetic retinopathy. Diabetic patients should be aware of the risk of developing eye problems and should regularly examine their eyes. (Nondiabetic patients should also examine your eyes periodically by these controls help to detect the presence of diabetes and other diseases.)
To detect diabetic retinopathy, the ophthalmologist examines painlessly inside the eye using an instrument called an ophthalmoscope. The interior of the eye may also photographed to provide further information.
If diabetic retinopathy is detected, the ophthalmologist may use a second method of test to see which blood vessels are damaged. First, a fluorescent dye is injected into the patient's arm. The dye travels through the bloodstream and goes to the retinal vessels. Coloring photographs must be taken quickly as it flows through blood vessels of the retina.
This technique, called fluorescein angiography is used by the ophthalmologist to determine if treatment is necessary as laser or sometimes surgery to remove submacular membrane.
When diagnosing diabetic retinopathy, the ophthalmologist considers the age of the patient history, lifestyle, and the degree of damage to the retina, before deciding on the treatment and continue to monitor the progress of the disease. In many cases active treatment is not necessary and sufficient to perform regular checks by the ophthalmologist.
Probably the most significant treatment is the use of laser surgery to seal zones and areas affected blood vessels of retina which can deteriorate over time. This method involves directing a powerful beam of laser light against the damaged retina. Small laser burns stop bleeding by sealing blood vessels, forming small scars on the inside of the eye. This therapy reduces the abnormal growth of blood vessels and helps to bind the retina to the back of the eye. This treatment requires no incisions and is performed in the ophthalmologist's office. If diabetic retinopathy is detected early, laser photocoagulation surgery can stop the ongoing damage. In advanced stages of the disease can reduce the probability of loss of vision.
However, photocoagulation can not be used in all patients. Depending on the location and extent of diabetic retinopathy, and if the glass is too clouded with blood, use other treatment. In this surgical procedure called a vitrectomy, blood filling the vitreous of the eye is removed and replaced with an artificial solution. About 70% of patients experience improved vitrectomized vision. The ophthalmologist should recommend a vitrectomy the vitreous as blood begins to cloud, before it is organized. The time to raise a vitrectomy depends on the extent of damage to the eye and the contralateral eye state. However, if diabetic retinopathy causing detachment of the retina from the back of the eye, may cause significant vision loss or blindness unless immediately perform an operation to clean the vitreous and the retina set.
Successful treatment of diabetic retinopathy depends not only on early detection and proper treatment, but also the attitude and patient care. All medications should be taken to follow a strict diet and control of diabetes. Although physical activity present few problems with subclinical retinopathy, sports or activities involving sudden movements of the head, can increase bleeding in proliferative retinopathy. Exercise for patients with proliferative retinopathy should be moderate.
PREVENTION OF VISION LOSS
Early detection of diabetic retinopathy is the best protection against loss of vision. Even when no symptoms are observed, the diabetic patient should undergo a by an ophthalmologist at least once a year. These medical examinations should be scheduled more frequently after diabetic retinopathy diagnosed with possible bleeding. In many cases, careful control the ophthalmologist can begin treatment before the hearing impaired.