Definition & Overview
Eye inflammation, also referred to as ocular inflammation, is a condition characterized by the swelling of one or more parts of the eyes and is caused by a variety of factors that range from simple irritation to certain diseases.
The eye is made up of three different layers: retina, uvea, and sclera. The retina is the innermost layer while the uvea contains veins and arteries that supply blood to the eye. The outermost layer, which is called the sclera, serves as the protective layer and is white in color. The optic nerves that send signals from the eye to the brain for the interpretation of visual information are connected to the sclera at the back of the eye.
Inflammation can occur in any of the layers. The condition is thus classified according to the part of the eye that has been affected. The classifications are Scleritis, Anterior Uveitis, Intermediate Uveitis, Posterior Uveitis, and Panuveitis, which is a general term that refers to an inflammation that affects the entire eye.
Cause of Condition
Each classification has one or more corresponding causes. However, in some cases, doctors are unable to determine the exact cause of the condition.
Scleritis (anterior/posterior) – This condition is further classified into four different types: diffuse anterior, nodular, necrotising, and scleromalacia perforans. Although there are different known conditions that can contribute to the development of scleritis, almost 50% of cases have no known cause. Possible causes are rheumatoid arthritis, Systemic Lupus Erythematosus, Polyarteritis nodosa, and inflammatory bowel diseases.
Anterior Uveitis – Inflammation in this area usually include the iris and ciliary body. This condition is mostly a complication of diseases that affect other parts of the body, such as tuberculosis, bowel inflammation or colitis.
Intermediate Uveitis – Among the different types of uveitis, intermediate uveitis has the highest percentage of unknown causes. 69% of uveitis cases are of unknown origin while 22% are caused by sarcoid. The remaining are usually due to multiple sclerosis or Lyme disease. This form of uveitis is more prevalent in young adults.
Posterior Uveitis – 90% of posterior uveitis cases are caused by a condition called ocular toxoplasmosis. Other cases may be caused by allergies or immune system disorders, but a wide variety of infectious and non-infectious diseases may also cause the condition.
Panuveitis – This refers to the inflammation of the entire eye and can be caused by a variety of conditions and disorders, such as sarcoidosis, infectious endophthalmitis, Vogt-Koyanagi-Harada disease, and Behcet’s disease.
The symptoms of an eye inflammation depend on the part of the eye that is affected. Scleritis will produce symptoms, such as pain, redness, and watering. Anterior uveitis will have redness, pain, watering, photophobia, or raised eye pressure as symptoms. The condition may or may not affect vision. Intermediate uveitis will have symptoms such as floater and blurred vision. Patients with posterior uveitis will likely have a blurred vision. Patients diagnosed with panuveitis will likely display all of the symptoms mentioned above.
Who to See & Types of Treatment Available
Patients who experience the symptoms listed above should consult an ophthalmologist as soon as possible. If an eye inflammation is not treated in time, it can cause serious complications including permanent blindness.
To make an accurate diagnosis, a series of tests will be performed and these typically include a thorough evaluation of the condition, review of the patient’s medical history, and a comprehensive physical examination to check for any visual evidence of an inflammation. Other laboratory tests will also be performed to determine possible causes, such as infections or autoimmune disorders. Meanwhile, the eyes will be check through various eye tests, such as an eye chart or visual acuity test, an ocular pressure test, a slit lamp test, and a funduscopic exam.
- A visual acuity test or eye chart test is performed to determine if your vision has decreased.
- An ocular pressure test determines the pressure inside the eye and is performed using an instrument called a tonometer.
- A slit lamp test is a non-invasive eye exam that is performed to inspect the entire eye.
- A funduscopic exam is performed to inspect the back of the inside of the eye. It is also non-invasive and is performed using an ophthalmoscope
The tests are expected to help the ophthalmologist determine the exact condition and its severity. Following making a diagnosis, the doctor will proceed by designing an individualized treatment plan that will be based on the underlying condition and the affected portion of the eye.
Anterior uveitis is usually treated using eye drops that contain steroids. The eye drops dilate the pupil and prevent muscle spasms.
Interior uveitis, posterior uveitis, and panuveitis are treated using oral medications, injections around the eye, or time-release capsules that are implanted inside the eye. The doctor may also prescribe medications that suppress the immune system if it is determined that it contributes to the development or progression of the condition.
It’s important to understand that ophthalmologists may not be able to determine the exact cause of eye inflammation as there is still so much that needs to be discovered about uveitis and ocular inflammation. Researchers around the world, such as those in the National Eye Institute, are aggressively searching and investigating possible causes to formulate new treatment methods and determine the risk factors.
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