Uveitis
The eye has three major layers in the eye wall. The outer wall is the sclera. This provides strength to the eye. The next layer is the uvea. This is mainly a blood circulation layer and thirdly the inner most layer is the retina. This layer sends the seen image to the brain.
"itis", in uveitis means inflammation just as "itis" in arthritis stands for inflamed joint.
During inflammation of the uvea the blood vessels dilate and start to leak protein fluid and blood cells.
This inflammation can occur in the front segment of the eye when it is called anterior uveitis or iritis, in the intermediate segment of the eye when it is called intermediate uveitis or iridocyclitis and in the posterior segment of the eye when it is called posterior uveitis or choroiditis.
CAUSE
The cause of uveitis is usually idiopathic, that is unknown. Infections with virus (shingles, mumps, herpes) or with a fungus (histoplasmosis) or with a parasite (toxoplasmosis) can cause uveitis.
Sometimes uveitis points to problems in the body elsewhere, chest (sarcoidosis), bowel (ulcerative colitis or Crohn’s disease), lower spine (sacro-ilitis), skin (psoriasis), joints (rheumatoid arthritis), genito-urinary system (Bechets).
The onset of symptoms may be sudden and painful (acute uveitis) or may be slow and subtle (chronic).
The acute form shows itself as a red ring on the white of the eye surrounding the coloured part of the eye with a small pupil. The patient complains of pain going from dim lighting out into bright lighting or pain when they focus to light a cigarette. This pain is one sided and is on the side of the red eye.
The pain of iritis is caused by the inflammation, which sensitises the pain nerve endings. These nerve endings are stimulated when the muscles within the eye contract in response to light (pupil constriction) or in response to accommodation, that is focusing on near objects (ciliary body muscle, this muscle alters the power of the lens to change focus).
It is important to have eye doctor care for these episodes to try and prevent complications. In the front segment of the eye the leaking proteins and inflamed iris can lead to the iris sticking to the front surface of the lens. This then can lead to blockage of the pupil (central hole in the iris). If a complete blockage occurs this can lead to painful glaucoma. Severe or prolonged uveitis can predispose to cataracts. Inflammation of the choroid (posterior uveitis) can have a detrimental effect on the overlying retina leading to waterlogging of the retina (cystoid macular œdema) with associated reduction in sharpness of the vision.
The doctor makes the diagnosis by looking with a microscope and shining a light beam through the front chamber to see if he can see evidence of inflammation. When this is present it looks like the beam of a projector light shining through a smokey, dusty atmosphere.
Your doctor will ask questions to see if there are any pointers to any underlying body problem or infection. If there are no pointers then often no further investigations will be done if this is the first episode of anterior uveitis.
TREATMENT
The treatment for uveitis is steroid drops and dilating drops. It is important to following the instructions of your doctor to the letter and not miss any drops to avoid a protracted course. Furthermore they should not be stopped prematurely otherwise the uveitis will return.
Occasionally a pressure rise can occur as a result of using the steroids drops. In this situation the medication is changed and glaucoma treatment added. However, unlike normal glaucoma treatment which is for life, this treatment is only temporary during the secondary pressure rise.
LINKS
This information site has been provided by varied UK and US eye doctors for patients with eye problems.
Once your eye doctor has made a diagnosis or recommended an investigation or treatment, then you will be able to find further explanation on this site.
It is not a self diagnosis centre. It should not be relied upon without taking professional advice.