Uveitis: Everything You Need To Know

What Is Uveitis?

Uveitis is an eye condition which involves inflammation of the uvea, the middle layer of the eye with many blood vessels.

The uvea consist of three main parts: the iris (the coloured part of the eye that controls the amount of light entering the eye), the ciliary body (which produces the fluid in the eye and controls the shape of the lens for focusing, and the choroid (a layer of blood vessels between the retina and sclera that provides nutrients to the retina. The presence of blood vessels makes the uvea susceptible to inflammation.

Around two to five in every 10,000 people are affected by uveitis in the UK every year, according to the Royal National Institute of Blind People. Uveitis affects people of any age, but most commonly between the ages of 20 and 59 years.

Types Of Uveitis

Uveitis is classified based on the part of the eye it affects. Each type varies in symptoms, severity, and underlying causes.

The known types of Uveitis include:

1. Anterior Uveitis: This refers to inflammation primarily involving the front part of the uvea which includes the iris or ciliary body. It can be linked to autoimmune diseases like ankylosing spondylitis, rheumatoid arthritis, or infections. It is the most common form of uveitis.
2. Intermediate Uveitis: This involves inflammation of the ciliary body and front part of the choroid, seen in the vitreous gel. The inflammation is deeper in the eye compared to anterior uveitis. It can be chronic and may require long-term management to prevent complications.
3. Posterior Uveitis: This can be defined as inflammation that affects the back part of the eye, including the choroid and/or retina, retinal blood vessels or optic nerve head. It often takes longer to resolve because of its deeper location.
4. Panuveitis: This describes inflammation of all parts of the uvea. It is often the most severe form of uveitis, and requires aggressive treatment to control inflammation.

Symptoms Of Uveitis

Uveitis affects people in different ways depending on which part of the uvea and eye is affected (front, middle or back). Some symptoms can be less obvious, making uveitis more difficult to diagnose initially. Some people may not notice any symptoms so uveitis can be undetected for several weeks or months.

The signs, symptoms and characteristics of uveitis may include:

1. Eye redness.
2. Eye pain.
3. Light sensitivity.
4. Blurred vision.
5. Floaters (dark, floating spots in your field of vision).

Causes Of Uveitis

There are several known causes for uveitis but sometimes the cause is unknown. Possible causes include:

1. Autoimmune and Inflammatory Conditions: Often in uveitis, the inflammation only affects the inside of your eye, but sometimes it can be connected to an inflammatory condition elsewhere in your body. Sometimes you may not even know that you have another inflammatory condition at the time the uveitis first develops. Uveitis may develop in people who have an underlying autoimmune condition which is where the immune system (body’s defence mechanism) mistakenly attacks healthy tissues.
2. Infections: Uveitis can be caused by viral, bacterial or parasitic infections. Examples can include herpes simplex (cold sores), herpes zoster (chickenpox and shingles), or cytomegalovirus, tuberculosis, syphilis, or toxoplasmosis. Many of these infections which cause uveitis are more likely if you have a poorly active or suppressed immune system. This includes people who have had organ transplants, leukaemia or HIV and AIDS.
3. Injury: An injury to your eye can cause uveitis in that eye. A very severe injury can even trigger the immune system to cause uveitis in the other eye, known as sympathetic ophthalmitis or sympathetic ophthalmia. This is very rare and only an injury through the eyeball wall (penetrating injury), needing an operation to repair, can lead to sympathetic ophthalmitis.
4. Idiopathic: Sometimes it’s not possible to work out what the cause of your uveitis is. When it is not clear what the cause is, the uveitis is considered idiopathic.

Long-term Complications Of Uveitis

Uveitis is considered a potentially sight-threatening condition. It needs to be treated promptly to try to reduce the risk of further problems.

Some of the complications of uveitis include:

1. Glaucoma: Untreated anterior uveitis can slow down the drainage of fluid within the eye, causing the pressure in the eye to rise. If not detected, monitored, or treated, this raised pressure causes damage to your optic nerve (made up of nerve cells carrying light signals to the brain), resulting in glaucoma.
2. Macular Oedema: Prolonged inflammation can result in a build-up of fluid inside the central part of the retina called the macula. This can cause difficulty in recognising faces, reading and watching television. Straight lines may appear wavy or distorted.
3. Cataract: The inflammation inside the eye can sometimes cause cloudiness of the lens. This cloudiness is called a cataract and can cause symptoms such as blurred or misty vision, colours appearing dull, or problems seeing clearly at night.
4. Neovascularisation: New blood vessel growth in the choroid and retina can be seen in some forms of posterior uveitis, but this isn’t a common complication. Choroidal neovascularisation (CNV) occurs where abnormal blood vessels grow through from the choroid into the retina, through an area of weakness.
5. Retinal Detachment: In posterior uveitis, the inflammation can cause fluid to collect under your retina to the extent that it comes away or is detached from the back of the eye. Alternatively, the inflammation can cause pulling on the retina or a hole to develop in the retina, leading to retinal detachment.
6. Permanent Vision Loss: In untreated or recurrent cases, uveitis can cause irreversible damage to the eye’s structures.

Diagnosis And Treatment

Uveitis is diagnosed by an ophthalmologist using a piece of equipment called a slit lamp, which consists of a microscope and a powerful bright beam of light. It allows them to check for signs of inflammation.

Treatment aims to reduce inflammation, prevent damage to the eye, and manage the underlying cause if known.. Treatment for uveitis can differ from person to person quite considerably and will also depend on the cause of your uveitis.

Here are some ways to treat this serious eye condition:

1. Corticosteroid Injections or Implants: Injections are used for intermediate or posterior uveitis to deliver the steroid to the parts of the eye that are inflamed. Injections can be given around the eye or into the eye. Steroids can be injected into the eye either as a liquid or as a small implant to treat non-infectious uveitis. Injections and implants are often used if only one eye requires treatment but can be administered to both eyes.
2. Corticosteroid Oral Medicine: Oral (tablet) corticosteroids are another way of treating intermediate or posterior uveitis. They may also be used to treat an underlying inflammatory condition elsewhere in your body. How long you’ll need to take oral corticosteroids will depend on how well your uveitis responds to treatment and whether you have an underlying inflammatory condition.
3. Immunosuppressants: These can help reduce inflammation by suppressing some of the activity in the immune system. They are important for people who need long-term medication to control their uveitis, since it would not be safe to take high-dose steroids long-term.
4. Anti-TNF drugs: These belong to a group of medications called biologics. Biological therapy treatments involve the use of drugs that alter a biological process occurring in your body. TNF (tumour necrosis factor) is a protein produced in the body that causes inflammation. Anti-TNF drugs block the action of TNF and so can reduce this inflammation. Anti-TNF medication may be given to people where treatments with corticosteroids or immunosuppressants have not worked or if they are causing health problems and the uveitis is causing worsening of vision.
5. Antibiotics, Antivirals, or Antifungals: If the uveitis is caused by an infection, treating the infection with appropriate medications is essential (e.g., antiviral drugs for herpes-related uveitis or antibiotics for bacterial causes like syphilis).
6. Cycloplegic or Mydriatic Eye Drops: Cycloplegic drops relieve your eye pain by paralysing the muscles of your iris and ciliary body as it is the movement of these inflamed muscles that cause the pain. Cycloplegic drops are also mydriatic, which means they cause your pupils to get bigger (dilate). This helps to reduce the risk of your iris sticking to the lens in your eye.
7. Surgery: In severe cases, such as if there is retinal detachment or persistent vitreous inflammation, surgical interventions like vitrectomy (removal of the vitreous gel) may be required.

If you have concerns about Uveitis, it's recommended to consult with an eye care professional or a specialist in visual impairments. They can provide a comprehensive evaluation and recommend appropriate interventions.

Got any questions regarding eye care and treatment? Please don’t hesitate to get in touch with us. We are more than happy to discuss queries with you over the phone (0800 093 1110) or email (enquiry@optimax.co.uk).