Uveitis is the inflammation of the uvea, which is the middle layer in the eye that includes the ciliary body, iris, and choroid. The uvea is responsible for providing a consistent supply of blood to the retina. The retina is the sensitive part of the eye that receives the images that we see and sends information of those images to the brain. Usually, this is red because of the blood supply that the uvea provides. While uveitis is a condition that is generally regarded as common and not particularly serious, there is also the possibility of having complications. In incredibly severe circumstances, uveitis may even lead to vision loss if it is not treated properly.

What Causes Uveitis?

Uveitis has dozens of potential causes. This is an issue because it can be very difficult to track down why someone has uveitis in the first place. After all, it’s much easier to treat a condition when you understand the underlying causes. Most of the time, this can be classified as chronic or reoccurring, leading to a range of potential complications including cataracts, clouding within the cornea, elevated pressure within the eye, swelling of the retina, glaucoma, or even retinal detachment in severe circumstances, with the possibility of vision loss.

Studies have found that the majority of uveitis cases occur in people between the ages of 20 and 50. According to a California study, there are currently more than 280,000 people within the United States with this condition each year and this is almost three times greater than previous estimates. The study, which was based on records from northern California communities also found that this could be the primary reason of around 30,000 new cases of blindness each year, and it may account for around 10% of all blindness. Anterior uveitis is the most common form, and its annual incidence is around 8 to 15 cases in every 100,000 people.

Uveitis generally occurs in otherwise healthy people who haven’t experienced any issues with their sight in the past. In some situations, the onset of the condition can be associated with the presence of another illness such as an infection, or even an autoimmune disorder.

Autoimmune diseases include:

• Sarcoidosis
• Crohn’s disease
• Kawasaki disease
• Arthritis
• Rheumatoid arthritis
• Psoriasis
• Ulcerative colitis
• Ankylosing spondylitis

Some examples of infection are:

• AIDS
• Herpes
• Histoplasmosis
• Tuberculosis
• Toxoplasmosis
• Syphilis
• West Nile
• CMV Retinitis

The other common causes of uveitis include a range of disorders, trauma to the eye such as from a blow to the face, and surgery. In some cases, this condition can be caused by excessive bruising, injury, or trauma, or if you have previously experienced a systemic disorder.

The Different Types of Uveitis

There are different types of uveitis, and the type that you have will be determined by the location of the inflammation in your eye.

Anterior Uveitis

Anterior uveitis, also known as iritis, takes place within the front of the eye, usually in the iris. The iris is the colored section of your eye that is located near the front of the eyeball. This form of uveitis is generally regarded to be the most common, and it can occur most often in people who are otherwise healthy. People who suffer from this type may find that the condition affects only one of their eyes, or both eyes at once. In most circumstances, this is the least severe form of the condition.

Intermediate Uveitis

As the name might suggest, this takes place towards the middle or central section of the eye. It is usually referred to as iridocyclitis, and it’s worth remembering that the word intermediate is only used to describe the location of the inflammation and not the severity of the condition. The middle part of the eye is made up of the pars plana, which is the part of the eye that exists between the choroid and the iris. This form of uveitis occurs frequently in healthy people, but it has generally been linked to many autoimmune conditions like multiple sclerosis.

Posterior Uveitis

Posterior uveitis is sometimes regarded as choroiditis because it affects the choroid part of the eye. The blood vessels and tissues that make up the choroid are incredibly important because they are responsible for delivering blood to the back portion of the eye. This form of uveitis generally occurs in people who are suffering from an infection as a result of a fungus, parasite, or virus. In some cases, it can also occur within people who suffer from an autoimmune disease. In many situations, this type is the most severe form because it can lead to scarring within the retina. Fortunately, this is also the least common form.

The Common Symptoms of Uveitis

Around half of the uveitis cases don’t have any obvious cause. Symptoms can be wide ranging and may differ from one patient to another. In most circumstances, they will involve things like decreased visual acuity, light sensitivity, redness in and around the eyes, and pain. Intermediate and posterior uveitis can be painless in some cases, but they still have a variety of symptoms to watch out for, including blurred vision and floating images in the eyes. Some of the most common symptoms of uveitis are:

• The presence of random spots within the visual field
• Cloudy or blurred vision
• Sensitivity to light that is also known as photophobia, which can actually lead to increased pain when you are exposed to light
• Bloodshot or red eyes
• Painful, burning, or aching eyes

Symptoms can take place in one or both of the eyes. Aside from the redness around the eyes, the only visible signs of uveitis are generally incredibly small, and can only be noticed by an ophthalmologist who is using a slit lamp microscope. During a proper examination, white blood cells may be spotted in and around the uvea of the eye, as well as in the front portion of the eye just beneath the cornea.

Common Complications of Uveitis

In some circumstances, untreated uveitis can lead to a range of serious conditions and complications, including:

• Loss of vision – either fully or partially
• Retinal detachment – which is a medical emergency
• Glaucoma – which develops from high pressure in the eye
• Cataracts – which results in clouding of the cornea or lens

Most of the time, uveitis will simply disappear within a few days when the right treatment is applied. However, uveitis that affects the back of the eye will generally heal far more slowly than the other types. In all cases, relapses can be a common problem. Treatment will depend on the cause of the condition and the kind of uveitis. Usually, eye drops are a common solution, but if you are having problems as a result of another condition, then the treatment may focus on eliminating that condition first. The goal of the various available treatments is generally to reduce the amount of inflammation within the eye and get rid of symptoms.

Treatment for anterior uveitis can include the use of dark glasses, eye drops which dilate the pupil and reduce pain, and steroid eye drops to reduce irritation and inflammation over time. Treatment for posterior uveitis can include steroids that are taken orally and visits to various specialists who will help to treat the underlying autoimmune disease or infection. Usually, a large infection will be treated with antibiotics. Treatment for intermediate uveitis will include the use of steroid drops and steroids that are taken orally. Some severe cases might require the use of drugs to suppress the immune system.

Most cases of uveitis can be prevented simply by seeking appropriate treatment for infections and autoimmune diseases. However, it’s worth noting that uveitis in otherwise healthy people can be difficult to prevent because the cause is not yet known. In any case, early treatment and detection are essential in reducing the risk of possible vision loss.

Resources and References:

• Uveitis, Iritis and Eye Inflammation – Information on uveitis and iritis and treatments (AllAboutVision.com)
• Uveitis – Basic information on uveitis, including signs and symptoms and treatment (MedicineNet.com)