Introduction
Affection of the retina due to diabetes is called diabetic retinopathy (DR). Diabetes is a very common problem affecting us, people of Indian descent/origin. Just like hypertension or high blood pressure, it is a silent killer. More recently, an increasing incidence of the problem has been noticed in the Indian population.
Importance of early detection
Diabetic retinopathy can be diagnosed early if a person suffering from diabetes visits an eye specialist regularly. A baseline check of the eyes and retina on detection of diabetes is advised. This will serve not only to detect any early signs of diabetic retinopathy at the outset, but also act as a baseline for further check-ups.
Symptoms of DR
Incidentally, a person who has a lot of findings of diabetic retinopathy may not have any symptoms. Hence it is called a silent killer. The need for regular check ups cannot thus be over-emphasized. It has been shown in several studies that after a period of about 15-20 years, almost all patients with diabetes, irrespective of good or poor control of their blood sugar levels will have one or the other finding of DR. Hence, the duration of diabetes is also an important factor in diabetic eye check up.
Some patients may present with blurring of vision, some may present with black spots in front of the eye and/or flashing lights and some may present with sudden loss of vision.
Pathology of DR
The major problem as far as pathology of the condition is concerned is primarily due to 2 causes.
- Occlusion/blockage of blood vessels
- Leakage from blood vessels
Diabetes causes abnormal changes in the blood vessels of the retina. Due to this some blood vessels become blocked, leading to decrease in blood supply to certain areas of the retina. This leads to a cascade of events in the retina, ultimately leading to new blood vessel formation. These new blood vessels are tiny, fragile and tend to bleed spontaneously. This causes bleeding at the back of the eye.
On the other hand, some blood vessels affected by diabetes start leaking components of fluid part of the blood. This leads to swelling of certain important areas of the eye leading to reduced vision.
If these problems are left untreated, new blood vessels may cause further bleeding leading to total loss of vision in the involved eye, high pressure causing severe pain in the eye and loss of vision. There may also be membranous band formation and retinal detachment.
Examination and Special investigations
The ophthalmologist (eye specialist) instills certain drops in the eye to make the pupil wider. Then he/she uses a bright light and lens to examine the retina
In some cases, the treating ophthalmologist may take photographs of the back of the eye, called fundus photographs, to document findings and refer them in the future for comparative purposes.
In certain instances, depending on the retinal findings, he/she may also advise a dye test called Fundus fluorescein angiography (FFA) to identify areas of leakage of fluid or blood from the normal or abnormal blood vessels.
2 Fundus photographs showing diabetic retinopathy changes with bleeding
Treatment Options
Recent advances have thankfully provided some treatment options for diabetic retinopathy. Most important of which is effectivecontrol of blood sugar levels or essentially of diabetes. This has been shown in several studies to forestall the onset of DR. Dietary alterations are also an important part of treatment.
A time-tested form of treatment is laser. This can be to areas of leakage as described earlier and also to areas where there is growth of new blood vessels. Laser can shrink the swelling as well as cause shriveling up of the new blood vessels.
Certain injections in/around the eye can also help reduce the swelling of the retina and improve vision.
Eventually, in certain uncontrolled cases, surgery (known as Vitrectomy) may be the only option available. This is in cases where there has been significant bleeding in the eye or the membranous bands have caused a retinal detachment involving certain important areas at the back of the eye. The outcome varies depending on a case to case basis.
Conclusion
In conclusion, diabetic retinopathy is responsible for a significant proportion of patients for a retinal surgeon. The most important variables in DR are the control of diabetes and its duration. Regular eye checkup for a diabetic patient is a must for early detection of changes of DR and so is regular of blood sugar level monitoring.
Treatment options are available but best option is not to reach the stage of treatment. As they say ‘Prevention is better than cure’. |
