Symptoms are not visible properly in the case of hypertensive retinopathy. Some patients might report reduced vision or headaches. Arteriolar changes like narrowing of arteries, advanced retinopathy lesions, like micro aneurysms, flame hemorrhages, ischemic changes and hard exudates around the retina called visual acuity loss. The affected patients might be asymptomatic or have reduced visual acuity in radiation retinopathy. Ophthalmic examination will show signs of retinal vascular disease that includes retinal hemorrhages, perivascular sheathing, disc edema and macular edema. Solar retinopathy has symptoms of long term reduced visual acuity and paracentral scotoma.

Some of the methods used for diagnosing diabetic retinopathy include visual acuity test, optical coherence tomography and ophthalmoscopy. The healthcare professional has to look for leakage in blood vessels, for damaged nerve tissue and retinal swelling. The findings of active retinopathy of prematurity are explained by the international classification of retinopathy of prematurity, which has several parameters for describing the disease. Examination of the back of the eye with funduscope will help in diagnosing purtscher’s retinopathy. The reduction in the blood flow to the white areas of the eye is measured by fluorescein angiography [8].

Three major treatment methods used for diabetic retinopathy are laser surgery, vitrectomy, and injection of corticosteroids. Laser photocoagulation, modified grid laser and panretinal photocoagulation, intravitreal triamcinolone acetonide are some treatment methods used for diabetic retinopathy [9]. Treatment for hypertension can reduce hypertensive retinopathy. Main treatment for retinopathy of prematurity is peripheral retinal ablation. Anti-vascular endothelial growth factors were used for treating radiation retinopathy. Purtscher’s retinopathy is treated using triamcinolone and if this is caused by any systemic disease, then they have to be treated [10].

Prognosis of retinopathy in newborns will be better by itself and the abnormal vessels will disappear after sometime. Advanced stage of retinopathy of prematurity can lead to blindness, retinal detachment, crossed eyes, nearsightedness, glaucoma, lazy eye and cataract. Diabetic retinopathy leads to blindness [7].

Alterations in the retina due to hypertensive retinopathy will slowly disappear when the blood pressure is reduced. The symptoms of damage will still remain in some cases. Retinopathy of prematurity is described as the threshold disease, which has 50 percent chance of progressing to retinal detachment, at stage 3 of zone I or zone II. Progression to stage 4 and 5 will lead to loss of vision. Purtscher’s retinopathy can also lead to vision loss.

Retinopathy can develop slowly or suddenly, which can result in permanent damage. Premature birth can lead to retinopathy, which can also end up in retinal detachment causing blindness. Type1 or type2 diabetic patients develop retinopathy when the blood vessels in their retina deteriorate. Thickening or blockage of small arteries or swelling of optic nerve causes hypertensive retinopathy. Non-traumatic systemic diseases and bone fractures leads to purtscher’s retinopathy. Disorganized growth of retinal blood vessels ending up in retinal detachment is thought to be a cause of Terry syndrome or premature retinopathy [3].

By 2012, of nearly 93 million people with diabetic retinopathy, 17 million were with proliferative retinopathy, 21 million people were suffering from diabetic macular edema and 28 million people were suffering from vision threatening diabetic retinopathy worldwide [4]. Research studies showed that degree and duration of hypertension enhances the retinopathy incidence. Another study reveals that large number of survived immature newborns correlate with increased risk of advanced retinopathy of premature stages. The frequency of this disease is inversely proportional to the gestational weight and age of the newborn. Prevalence of prematurity retinopathy varies from five to eight percent in developed countries to thirty percent in developing countries.

The formation of blood-retinal barrier is altered by the damages from thickening of the basement membrane and hyperglycemia induced intramural pericyte death leading to vascular wall incompetence. Tiny blood vessels filled with glucose cannot be exposed to glucose control methods. Therefore, initial stage of diabetic retinopathy is called non-proliferative and the advanced form is called proliferative [5].

If the growth of blood vessels is abnormal from the plane of retina, and if it bleeds inside the eye, then the baby develops retinopathy of prematurity. Radiation retinopathy involves damage of the endothelial cells of the retinal capillaries by radiation. Retinal damage occurring from photochemical injury is observed in solar retinopathy. Appearance of cotton wool like spots in the retina and atrophy of the optic nerve is observed in purtscher’s retinopathy [6].

Prevention of retinopathy of prematurity can be done by addressing certain questions like how to identify the population at risk for this disease, ideal treatment needed for the affected people, what to do when treatment fails. Regular screening of blood sugar levels and high blood pressure can keep diabetic and hypertensive retinopathy under control.

There are several types of retinopathy, like diabetic retinopathy, hypertensive retinopathy, retinopathy of prematurity, radiation retinopathy, solar retinopathy, sickle-cell disease, retinal vascular disease and purtscher’s retinopathy. Diabetic retinopathy is due to microvascular retinal changes, which also result from radiation. Hypertensive retinopathy occurs due to the damage in the arterial and arteriolar circulation from high blood pressure. The eye disease that affects prematurely-born babies has received intensive neonatal care due to retinopathy of prematurity [2]. Solar retinopathy results due to eye damage from the sun. Head injuries can lead to purtscher’s retinopathy and sickle-cell anemia also leads to retinopathy.

• Definition: A permanent or temporary damage occurred to the retina of the eye is termed as retinopathy. Ocular manifestation of systemic diseases like diabetes and hypertension, prematurely born babies, radiation, and other reasons can lead to retinopathy.
• Cause: Enhanced blood sugar levels and blood pressure, bone fractures, disorganized growth of retinal blood vessels in the newly born, radiation and sun effect are some of the causes for retinopathy. 
• Symptoms: Changes in the arterial wall, advanced retinopathy lesions, micro-aneurysms, ischemic changes, flame hemorrhages, visual acuity loss, retinal detachment, perivascular sheathing, disc edema, macular edema and paracentral scotoma are some of the symptoms of retinopathy.
• Diagnosis: Some of the tests used for diagnosing diabetic retinopathy include visual acuity test, optical coherence tomography and ophthalmoscopy. Purtscher’s retinopathy is screened using funduscope. Fluorescein angiography is used for measuring the flow of blood to the eye. 
• Treatment: Laser surgery, vitrectomy, and injection of corticosteroids are the major methods used for treating diabetic retinopathy. Peripheral retinal ablation is done for treating retinopathy of prematurity. Anti-vascular endothelial growth factors and triamcinolone are used in the treatment of radiation retinopathy and purtscher’s retinopathy respectively. 

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