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In this section, we provide some basic information about the eye as well as the most common signs, symptoms and disorders of the Retina and Vitreous. We eagerly await your feedback so as to provide only the most useful information to our valuable patrons. Choose a topic below to learn more:

Diabetic Retinopathy & Diabetic Macular Edema

Unfortunately, Diabetes has assumed epidemic proportions in the USA and a lot of other countries in the world. The culprit is none other than our own eating habits (excessive sweets) and certain ingredients such as corn syrup (present in many food items) that lead to unwarranted carbohydrate levels in the body. Sedentary life-styles and lack of exercise/fitness regime are highly contributory to the same. Diabetes often accounts for changes in the Retina, i.e. Diabetic Retinopathy. These unwanted changes occur after a decade or more of diabetes in an individual, but are asymptomatic to begin with and remain so for a long period of time (especially in Type- 2 diabetics). Early signs of Diabetic Retinopathy include small hemorrhages in the eye, as well as dilations known as "microaneurysms" within the tiny ocular blood vessels. The first symptoms will include reduction in vision, though gradually. The Retina under such circumstances is deprived of adequate blood supply. This results in the Retina sending out "chemical signals" to demand more blood supply. The unfortunate response to this signal is the development of the small, abnormal blood vessels in the Retina, known as "Neovascularization." This condition constitutes "Proliferative Diabetic Retinopathy." It is of paramount importance for diabetic individuals to have a regular retinal eye exam for early detection of this condition, if at all.

At times, these changes in the Retina cause disruption of the Retinal blood vessels, resulting in leakage of blood through their walls and subsequent accumulation within the layers of the Retina (he Retina is a ten layered structure). This leads to a swelling in the center of the Retina, i.e. at the Macula. This condition is called Diabetic Macular Edema. Involvement of the fovea, which forms the center of the Macula, leads to blurriness and distortion of vision.

These changes are detected quickly by an investigation known as Fluorescein Angiograpy, wherein a dye called Fluorescein is injected into the individual’s vein. Through the blood stream, this dye reaches the retinal blood vessels and picks up any leakage or obstruction that might be present.

Management of Proliferative Diabetic Retinopathy is carried out by using Pan Retinal Photocoagulation (PRP), which prevents the progession of "Neovascularization".

Treatment options for Diabetic Macular Edema include Laser Photocoagulation, wherein laser beams are used to seal the leaking spots on the abnormal blood vessels, or an Intra-Vitreal injection known as Kenalog*, used to reduce the swelling in the Retina. At this point in time, an oral drug for the treatment of Diabetic Macular Edema is undergoing clinical trials.

*Kenalog currently does not have FDA approval for injection within the eye, though it has been approved for use in treatment of inflammatory conditions elsewhere in the body. The use of Kenalog in the eye is thus on an investigational or experimental basis.

Hypertensive Retinopathy

As the name suggests, the primary factor responsible for the development of this retinal disorder is high blood pressure, i.e., hypertension; long standing cases are pre-disposed in particular. The Retinal blood vessel walls harden due to the long standing effects of hypertension, resulting in narrowing of the vessel lumen, i.e., the blood vessel becomes incapable of handling the amount of blood flow it normally was used to. There may then a breakdown of the internal "Blood-Retinal Barrier", giving rise to leakage of blood through the vessel walls and hence the development of hemorrhages and microaneurysms in the eye. Occasionally, the vision loss can be sudden, as is seen in retinal vascular occlusions. Obviously, loss in vision is the end result. Management of this disorder involves regular eye check-ups in patients harboring a history of hypertension, as well as control of the blood pressure using suitable lifestyle with dietary modifications and anti-hypertensive agents.

Vascular Disorders of the Retina

These are a group of disorders that include, but are not limited to the following:

Central Retinal Vein Occlusion (CRVO)
A condition in which the principal vein of the Retina, the Central Retinal Vein, is blocked due to a blood clot. Blood starts leaking out through its walls due to a pressure build-up inside the blood vessel on account of obstruction to blood flow. This leads to the formation of hemorrhages/edema in the eye. The progression of this disorder is gradual, and the symptoms include slow but sure blurriness in vision, and floaters. Some conditions that pre-dispose to CRVO include Hypertension (high blood pressure), Glaucoma (increased pressure within the eye) and Diabetes. Treatment modalities include drug therapy to reduce the swelling in the eye and/or dissolution of the clot, as well as Laser Therapy.

Branched Retinal Vein Occlusion (BRVO)
BRVO is so called when a smaller vein of the Retina is affected as in CRVO. The symptoms remain nearly the same, as do the pre-disposing factors.

Central Retinal Artery Occlusion (CRAO)
This is a condition characterized by sudden, rather instantaneous and drastic drop in vision. It occurs as a consequence of the formation of a blood clot (thrombus) within the Central Retinal Artery, which forms the main source of blood supply to the Retina. At times, a blood clot formed in another blood vessel in the body dislodges from its primary position and is carried by the flow of blood into the Central Retinal Artery (embolism), where it gets impacted. Both the thrombi as well as the embolisms lead to cessation of blood supply to the Retina and thus the condition being described. Atherosclerosis of an artery forms the most important pre-disposing factor. CRAO, however, is an absolute emergency and may result in drastic, permanent loss of vision if not treated within the first twenty four hours of the onset of symptoms. Some amount of irreparable damage to the Retina may occur within the first ninety minutes of commencement of symptoms, if left untreated. Treatment options include massage of the eyeball (Ocular Massage), inhalation of a specific oxygen and carbon dioxide mixture, draining fluid from the front of the eye to lower pressure in the eye (Anterior Chamber Paracentesis) and drug therapy with an intension to dissolve the blood clot.