DIABTEIC RETINOPATHY – diabetes is a metabolic disorder in which either there is shortage of insulin to metabolise sugar or there is development of Insulin resistance because of which it doesn’t act properly. The functional deficiency of Insulin leads to raised blood sugar levels which can damage the kidneys, eyes and multiple organs. Long standing and uncontrolled diabetes leads to damage to the blood vessels of the retina leading to Diabetic retinopathy.
Retinal Disorders treatment types-
NON PROLIFEARTIVE DIABETIC RETINOPATHY ( NPDR)- in this the small blood vessels supplying the retina are damaged which can cause them to swell. They become leaky leading to exudation of fluid and proteins (exudate formation and macular edema). They may bleed leading to multiple areas of bleeding in the retina or they may get blocked resulting in stoppage of blood supply to a particular area (macular ischemia, capillary non perfusion areas)
Most diabetics after 10-15 years of diabetes develop NPDR. However mild and moderate NPDR usually cause few symptoms. There is hardly any vision loss in mild NPDR.
in moderate and severe cases, the loss of vision may be much more especially if it is associated with swelling in macula.
For swelling in the macular area, there are two modalities of treatment.
Injections – in this method injections are given inside the eye ( intravitreal injections). These drugs are known as anti VEGFs, like Bevacizumab( Avastin), Ranibizumab( Lucentis), Aflibercept ( Eyelea) and steroids . these drugs inhibit the growth of abnormal vessels which are leaky and thus they reduce the swelling in the macular area (macular edema) Repeated injections may be required . follow up is done regularly by doing repeated Fundus Fluorescein angiography and checking the thickness of the macular area by Optical Coherence Tomography (OCT). other test may be done if there is the need like OCT angiography.
LASER treatment for Diabetic Retinopathy- Laser treatment is needed in cases of severe NPDR where there ismarked retinal ischemia ( loss of blood supply to retina). LASER selectively destroys those areas which are deprived of blood and oxygen. LASER is also helpful in treatment for macular edema and helps to decrease it.
2. PROLIFERATIVE DIABETIC RETINOPATHY – in this there is formation of new vessels on the retina. These new vessels may also sometimes bleed into the vitreous gel leading to either floaters or marked loss of vision. These new vessels then fibrose over time leading to formation of scar tissue which contracts leading to retinal detachment. This leads to sudden and marked loss of vision. Gradually this disease leads to loss of optic nerve and retinal damage.
The treatment modalities mainly comprise of –
Injections – form the mainstay of therapy. Intravitreal injections of anti VEGF drugs like Lucentis, EYELEA, Avastin and steroids leads to marked regression of blood vessels. Thus they disappear after some time. However, repeated injections may be required and regular follow up usually monthly or 2 monthly is needed.
Laser treatment – pan retinal photocoagulation is preferred laser in PDR. In this retinal areas in the periphery (360 degrees) which is devoid of blood and oxygen is selectively lasered. Also laser in the macular area may be done if there is an associated swelling ( macular edema)
Vitrectomy – is needed where there is bleeding inside the eye ( vitreous haemorrhage ) or retinal detachment. In this the vitreous gel is removed and along with it haemorrhage is also cleared. If there is retinal detachment then the traction bands, pulling the retina is removed, any associated retinal hole is closed and lasered by endolaser and retina is flattened by putting silicone oil or gas ( c3f8). The Gas is absorbed on its own in 3 weeks but silicone oil has to be removed by a repeated surgery 3 months later.
Vitrectomy however has its own complications
Cataract forms if a patient does not have cataract before
Glaucoma – the pressure of the eyeball may rise due to multiple reasons
Oil may enter in front of the iris in selective patient
Corneal complications can occur due to glaucoma or oil droplets migrating anteriorly.
There is always a risk of re bleeding and re detachment of retina.
Inspite of everything diabetic retinopathy may still progress especially if patient’s blood sugar is not controlled.
Retinal venous occlusions – these basically include Central retinal vein occlusion ( CRVO) and Branch retinal vein occlusion ( BRVO). In this there occurs blockage in the veins supplying the retina which leads to dilatation of veins beyond the blockade, multiple harmorrhages and areas of swelling in retina ( macular edema). In CRVO, this occurs extensively in all the quadrants but in BRVO it is locayed to a particular quadrant only. Patient usually complains of sudden loss of vision preceeded by floaters. This vision loss is more severe in CRVO.
The treatment comprises of –
Injections – the mainstay of treatment on these cases is intravitreal injections. These injections are known as Anti VEGF agents . they decrease the formation of new vessels, help in clearing the macular edema and also improve vision. however repeated injections may be required.
Laser treatment – it may be required in cases wwhere there are extensive areas of loss of blood supply and oxygen to retina ( hypoxic areas). Laser selectively destroys those areas, decreases the formation of new vessels and prevents re bleeding and also decreases Macular edema .
Age related macular degeneration – it is of two types –
1.DRY ARMD – in this there is formation of small whitish yellow spots at the seeing area of the eye ( macula). There is mild loss of vision initially. However, in late phases due to scarring at the macula, there may be marked loss of vision.
Treatment is mainly antioxidant capsules in early stages and regular follow ups.
2. WET ARMD – in these abnormal blood vessels grow under the macula and gradually these vessels can leak leading to exudate formation, they may rupture causing hemorrhage and in later stages there is marked scarring. The loss of vision is more marked in this. There is meta morphosia ( straight lines appear wavy). If left untreated then vision loss can be very severe.
The treatment mainly comprises of intravitreal injections of anti VEGF agents like Ranibizumab, Bevacizumab and Aflibercept or intravitreal steroids. Intravitreal injections may have to be given monthly, in some cases 3 monthly injections may be given.
Lasers can be used as an adjunct to treatment along with intravitreal injection.
What is wet ARMD?
In this abnormal blood vessels grow under the macula which lead to exudation and haemorrhage at the macula and loss of vision.
Which is worse, dry or wet ARMD?
Vision is gradually affected in both the conditions. However, wet ARMD is associated with more profound loss of vision.
Is macular degeneration age related?
It usually occurs above the age of 60 years.
How do you correct age related macular degeneration?
The treatment mainly comprises of anti VEGF injections, Lasers and Photo dynamic therapy.
What causes age related macular degeneration?
The most important risk factors are – increasing age, obesity, high BP, smoking, positive family history etc.
Can age related macular degeneration be cured?
There is no definite treatment, however with the available treatments, the progress of the disease can be slowed and even vision can be improved in many cases.