The retina is one of the target tissues most sensitive to metabolic changes in diabetic patients.
During the diabetic patient's life, retinal disease may develop as different types:
- Background retinopathy: The mildest stage. Retina specialists detect minor alterations in retinal blood vessels with small fluid and/or blood leaks. During this initial stage, there tends to be no sight loss.
- Macular oedema: The most common cause of sight loss in diabetic patients. Macular oedema is due to the accumulation of plasma-derived fluid between the layers of the macular retina. Its prognosis strangely depends on whether a diagnosis is made at an early stage, before the patient is aware of decreased visual acuity.
- Proliferative diabetic retinopathy (PDR): Severe progression of background retinopathy. With this type of DR, abnormal vessels appear and grow on the retina, which are known as retinal neovessels. Neovessels are very weak structures that bleed easily, causing severe complications of the disease: intraocular haemorrhage (vitreous haemorrhage) and retinal detachment.
The importance of diagnosis
In order to make an accurate and early diagnosis of DR, periodic examinations of the back of the eye must be done from the onset of the disease.
From the onset of the disease, a six-monthly or annual examination of the back of the eye (depending on the type of diabetes) is recommended internationally in order to diagnose DR. At this examination, your ophthalmologist will dilate the pupil with dilating eye drops and will examine the retina using specialised instruments. DR can thereby be diagnosed during its early stages, making it possible to prescribe treatments to help prevent progression to more advanced stages of PDR, with a truly devastating impact on sight.
Your ophthalmologist will sometimes perform a more in-depth examination, performing complementary tests to help learn more about disease progress and to help plan subsequent treatment as accurately as possible. The most common tests are: retinography (photographs of the retina in order to screen for disease progression more accurately), fluorescein angiography (FA) (special photographs of the retina using an intravenous dye) and optical coherence tomography (OCT) (analysis of the layers and thickness of the retina)
Treatments, the ophthalmologist's weapons
With the development of endocrinology, and following the introduction of insulin in 1921 and other medical treatments and antibiotics, the quality of life and life expectancy of diabetics have improved remarkably. Paradoxically, however, the longer the patient's life span, the longer the time during which retinopathy can develop. It has been widely demonstrated that the frequency and severity of retinopathy are closely related to the duration of the endocrine disease. Luckily, better metabolic control always improves the prognosis for eye conditions, especially when blood glucose levels, cholesterol levels and high blood pressure are monitored.
If we look at the history of treatments for ocular complications of diabetes, we find two crucial developments: laser and microsurgery.
Ophthalmic lasers were developed for retinal photocoagulation. Thanks to this, the two main disorders of retinopathy can be treated with remarkable efficacy, with photocoagulation of both areas of ischaemia and areas of oedema. Applying laser at an early stage, when retinopathy is beginning to develop, reduces progression of the disease to more severe forms.
The second giant development involved new intraocular microsurgery technologies. Lighting, cutting, suction, laser photocoagulation and retinal manipulation systems have been perfected, especially over the last fifteen years, allowing many patients affected by vitreous haemorrhage and other complications of proliferative DR to be stabilised or even to regain their sight.
Glaucoma, as a complication of DR, can also be treated using Valvular Systems with remarkable success.
Important data for caring for diabetic patients:
- Control. Adequate control of your diabetes is the main decisive factor in diabetic retinopathy care. DR does not cause decreased visual acuity at the beginning. Therefore, DR can be present with no visual impairment.
- Early diagnosis. For all forms of diabetic retinopathy, it is vital that the condition is treated on time, right at the start of any sight-threatening processes.
- Experience. Laser treatment and vitreoretinal surgery for diabetic retinopathy are complicated, highly specific treatments and must be performed by specialised ophthalmologists.
The final success of present-day medicine is dependent on quickly and efficiently providing the best possible techniques to the largest number of patients who may benefit from such technology.