Uveitis is a type of eye inflammation that affects the uvea (middle layer) of the eye. It can be the result of infection or injury but sometimes occurs due to other inflammatory and autoimmune diseases.
There are a few different types of uveitis, depending on which part of the uvea is affected, so we put together this guide so you can understand the differences between them, and how they can be detected.
Types of uveitis
The uvea is made up of three structures: the coloured iris which controls pupil size; the ciliary body which secretes aqueous humour (a watery fluid which nourishes your eye); and the choroid layer which contains blood vessels. The type of uveitis is based on the part of the uvea affected by inflammation:
Anterior uveitis: Inflammation of the iris at the front of the eye. It’s also called iritis and is the most common type of uveitis.
Intermediate uveitis: Inflammation of the ciliary body in the middle of the eye.
Posterior uveitis: Inflammation of the choroid and retina in the back of the eye.
Panuveitis: This is an inflammation of all the layers of the uvea.
The type of uveitis can also be identified by how long it lasts, and if it comes back after treatment. Usually, each type falls into one of three categories: acute, chronic, or recurring uveitis:
- Acute uveitis tends to come on quickly and the symptoms can be quite severe, including redness, light sensitivity and pain. Usually, this type improves in three months.
- Chronic uveitis develops gradually, and symptoms tend to be less dramatic. Symptoms may include eye irritation, redness, and decreased vision.
- Recurrent uveitis is a type that goes through cycles of getting better and worse.
Uveitis symptoms can start suddenly or develop gradually, and can affect one or both eyes.
Detecting anterior uveitis symptoms
Symptoms of anterior uveitis include redness, discomfort, light sensitivity, and decreased vision. These uveitis symptoms usually start suddenly and can last for many weeks. The symptoms may be ongoing or they may come and go.
Detecting intermediate uveitis symptoms
The symptoms of intermediate uveitis usually affect one eye and include pain, light sensitivity, redness, and decreased vision. Intermediate uveitis symptoms can last anywhere from weeks to years. They tend to be cyclical, i.e., the condition gets better, then gets worse.
Detecting posterior uveitis symptoms
Symptoms of posterior uveitis include blurred vision, floaters (specks or strings in the field of vision), light sensitivity, blind spots, and eye discomfort. Posterior uveitis symptoms develop gradually and often continue for years.
Detecting panuveitis symptoms
The signs and symptoms of panuveitis can affect one or both eyes and may develop suddenly. They can include any combination of the previously mentioned signs and symptoms, such as pain, redness, light sensitivity, blurred vision, and floaters.
How uveitis is detected during an eye test
Due to the nature of the inflammation, uveitis can be difficult to detect and manage. As there are so many types of uveitis, many different parts of the eye can be affected, and there isn’t one common symptom which can definitively determine whether someone has uveitis. The condition varies from person to person.
There are several tests carried out during a routine eye examination to check for signs of uveitis. Your optometrist will often start by asking you to read a test chart through different strength lenses, to see if your visual acuity has changed.
Then, they’ll measure the pressure in your eye using a tonometer and assess the front and back of your eye with a powerful microscope called a slit lamp. Both of these procedures are non-invasive and painless. Your optometrist will also use an ophthalmoscope to examine the retina at the back of your eye, your optic nerve and its blood vessels.
If you’re experiencing persistent eye pain or an unusual change in vision, you should contact your optometrist as soon as possible. Your optometrist may refer you to an eye specialist who will examine your eye in greater detail as, in some cases, uveitis needs urgent attention.
What is the future role of OCT in uveitis management?
The standard tests for uveitis are based on assessing the main signs of inflammation and scoring them according to an industry-wide system of grading. This method, however, can be seen as unreliable, as the scores are subjective.1 One optometrist’s idea of a high score may not match another’s.
This is where OCT could come in. Research has been, and continues to be, carried out to assess whether optometrists could use OCT scans to more accurately detect and manage uveitis. By providing a clearer image, OCT scans could allow us to detect certain signs and complications of types of uveitis.2 Early studies are showing promise, but more work is needed before OCT scans can become the standard testing method for uveitis.3
Can OCT scans detect uveitis?
Yes and no. It’s important to remember that OCT scans are part of a wider eye exam process that includes other valuable tests. The training Specsavers’ optometrists go through and the equipment they have to hand will enable them to assess your symptoms and see if you have uveitis, or something else.
1. EQUATΘR. (n.d.). The Challenge of Assessing Uveitis. [online] Available at: http://www.equator.vision/chal... [Accessed 23 Jan. 2020].
2. Regatieri CV, Alwassia A, Zhang JY, Vora R, Duker JS. Use of optical coherence tomography in the diagnosis and management of uveitis. Int Ophthalmol Clin. 2012;52(4):33–43. [Online]. Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4131430/ [Accessed 16 November 2019].
3. Montesano, G., Way, C., Ometto, G., Ibrahim, H., Jones, P., Carmichael, R., Liu, X., Aslam, T., Keane, P., Crabb, D. and Denniston, A. (2018). Optimizing OCT acquisition parameters for assessments of vitreous haze for application in uveitis. Scientific Reports, 8(1).