RETINOPATHY; A SICKLE CELL COMPLICATION
In 1910, James Herrick first described sickle cell disease (SCD).
SCD is a disorder that affects the molecule called haemoglobin found in red blood cells whose function is to deliver oxygen to the cells in the body. SCD is caused by a mutation of this haemoglobin molecules which forms polymers in the red blood cells and causes them to become rigid and abnormally shaped, sickle-shaped.
Hence, the name Sickle Cell.
The signs and symptoms of sickle cell begins and manifests from childhood. Common features of this disorder are: low number of blood cells which is known as anaemia, infections and multiple episodes of somatic pains.
These symptoms are as a result of the sickling of the cells which when it happens, causes the red blood cells to break down prematurely thus leading to anaemia, which can result in shortness of breath, fatigue, and delay in growth and development in children. These spontaneous breakdown of red blood cells may also cause jaundice, a yellowing of the skin and eyes.
Pain can occur when sickled red blood cells become stuck in tiny red blood vessels thus blocking the flow of oxygen-rich blood to other organs and tissues. When these deprivation of oxygen occurs, it can result in organ damage especially of the lungs, brain and kidneys.
The nature and complexity of these signs and symptoms differ from one individual to the other. While some have mild and less complex symptoms, others have frequent symptoms and often require hospitalization for complications.
One of the various complications of
SCD is retinopathy.
Retinopathy occurs when the retinal blood vessels gets occluded and the retina becomes ischemic.
Retinopathy can go undetected for years without a thorough eye examination by an opthalmologist. It can occur in one eye or in both eyes. When it is left untreated for a longer time, it can result progress to proliferative sickle cell retinopathy which can cause bleeding into the eye or cause the retina to detach. Proliferative sickle retinopathy (PSR) is the most vision-threatening complication in sickle cell . In PSR, the blood vessels becomes clogged they revert from the retina rather than reforming thus depriving the retina of nutrients and when this happens, the retina can die or become damaged due to nutrient deprivation. The death or damage arising from this can be manifested as changes in vision and in some cases, blindness.
Anybody with sickle cell can develop retinopathy however, people with sickle-haemoglobin C disease (SC) are more prone to retinopathy as compared with SS.
SYMPTOMS OF RETINOPATHY
Signs and symptoms of retinopathy include eye pain, redness and soreness of the eyes, floaters, flashes, decreased visual acuity, loss of peripheral vision, retinal detachment and bleeding in one or more layers of the retina
MANAGEMENT AND TREATMENT OF RETINOPATHY
Treatment is aimed towards preventing the loss of vision from vitreous hemorrhage, retinal detachment and epiretinal membranes. Treatment may either be medical or surgical.
- Low-intensity scatter laser photocoagulation to areas of capillary non-perfusion: This scatter laser treatment shrinks the abnormal blood vessels. During this procedure, the areas of the retina are treated with scattered laser burns which cauae the abnormal blood vessels to shrink and scar. Blurred vision may occur and persist for a day after the operation. It us also worthy to mention that some loss of night vision after the procedure is likely to occur.
- Focal laser treatment: This laser treatment can stop or slow down the leakage of blood and fluid in the eye to the barest minimum. The leaks from the abnormal blood vessels are treated with laser burns. If the patient already has blurred vision before the surgery, the treatment may not restore the vision to normal but it ensures that the chance of the degeneration is reduced.
- Vitrectomy: A tiny incision is made in the eye to remove blood from the vitreous (middle of the eye) and scar tissue on the retina. This surgery can be done in a hospital using local or general anesthesia.