Diabetic retinopathy

Introduction

Diabetes mellitus is a chronic metabolic disorder in which there is an elevated level of glucose (sugar) in the blood, which the body cannot adequately use and store.

There are two types of diabetes mellitus (sugar disease). Type 1 (insulin dependent), which develops through an autoimmune reaction and the destruction of specific cells in the pancreas that are responsible for the production of insulin.

Type 2 (the insulin independent form) is manifested by a greater or smaller defect in the production of insulin by the pancreas but with the appearance of tissue resistance to the action of insulin. In the population of people suffering from diabetes mellitus (sugar disease), about 90% are type 2 (the insulin independent form).

What is diabetic retinopathy?

An elevated level of glucose in the blood damages the large and small blood vessels in the body. Damage to the blood vessels of the ocular fundus causes damage to the retina (one of the most sensitive parts of the eye responsible for vision). It is estimated that about 100 million people who suffer from sugar disease worldwide have diabetic retinopathy.

What influences the development of diabetic retinopathy?

The duration of sugar disease is one of the most important factors in the development of diabetic retinopathy.

Poorly regulated glycaemia (the level of sugar in the blood), arterial hypertension, kidney damage, an elevated level of lipids (fats) in the blood, anaemia and pregnancy also play an important role in the development and worsening of diabetic retinopathy. For that reason it is necessary that the values of three month sugar (HbA1C), serum lipids and blood pressure are kept within reference limits.

What are the symptoms of diabetic retinopathy and when should you contact your ophthalmologist?

Diabetic retinopathy mostly appears in both eyes. The fact that diabetic retinopathy in the early stages need not be accompanied by symptoms makes this disease dangerous, and for that reason regular check ups with an ophthalmologist are necessary.

The symptoms can vary, but if you notice the following complaints you should definitely contact an ophthalmologist:

Blurring of vision (a drop in visual acuity), alternating changes in the clarity of vision or complete loss of vision

The appearance of dark spots, dots, threads

Poorer perception of colours

Establishing the diagnosis of diabetic retinopathy

The diagnosis is established by an ophthalmologist on the basis of:

the medical history

a clinical examination (checking visual acuity, examination of the ocular fundus with a widened pupil, checking eye pressure)

OCT diagnostics

FA (fluorescein angiography)

Types of diabetic retinopathy

On the basis of the presence, absence and seriousness of changes in the ocular fundus, the ophthalmologist can classify diabetic retinopathy as:

Non proliferative diabetic retinopathy (NPDR)-without the development of new “pathological” blood vessels, but with the presence of microaneurysms and dot haemorrhages on the retina,

Pre proliferative diabetic retinopathy (pPDR) - with the development of larger abnormalities in the blood vessels and the appearance of haemorrhages in the ocular fundus.

Proliferative diabetic retinopathy (PDR), with the development of new “pathological” blood vessels, as a result of which haemorrhage into the vitreous body and retinal detachment can occur.

Diabetic maculopathy is a subentity of diabetic retinopathy and can appear in all of its stages listed above, and it is characterised by leaking from the blood vessels in the area of the macula or a blockage in the flow of the blood vessels of the macula.

Treatment of diabetic retinopathy

Treatment of diabetic retinopathy involves the application of laser photocoagulation (LFC) of the ocular fundus, where by the action of the laser we prevent leaking from the blood vessels into the retina and prevent the development of new “pathological” blood vessels.

The second method of treatment is the administration of an angiogenesis inhibitor drug (anti-VEGF) into the cavity of the eyeball, that is, intravitreally. Anti-VEGF are drugs that prevent the development of new “pathological” blood vessels and leaking from existing damaged blood vessels into the retina. There are several kinds of anti-VEGF drugs in use: bevacizumab (Avastin), aflibercept (Eylea), faricimab (Vabysmo).

If haemorrhage into the eye cavity occurs from “pathological” blood vessels with the development of membranes that can cause retinal detachment, we proceed to an operation of surgical removal of the blood and membranes which is called posterior vitrectomy (MIVS 23G).