The inside of the eye contains a vitreous gel, and is covered by an outer part consisting of three layers:
• The sclera – the white part of the eye
• The middle choroid layer containing blood vessels to nourish the layers
• The innermost light sensitive layer – the retina
The middle choroid layer is made up of several components forming the uveal tract – the iris at the front, with the ciliary body near the front having muscles and ligaments to change the shape of the eye lens, and the choroid.
Inflammations that occur in the uveal tract are named with regard to where they are – and of course they all end in “itis”, after the Greek word for inflammation:
• Iritis – fairly obviously at the iris!
• Uveitis – a general area classification for the uveal tract
• Anterior uveitis – in the front area, from the Greek word for “before”
• Posterior uveitis – at the rear of the eye – also called choroiditis
• Retinitis – at the light sensitive layer
When an inflammation involves both the choroid and retinal layers then it is given the name “chorioretinitis” or sometimes “retinochoroiditis”.
What are the symptoms of chorioretinitis?
• Vision becoming blurred
• “Pink” eye associated with pain
• Sensitivity to light sources
• Tears being continually produced
• Imagining to see “floaters” – cobweb-like structures that seem to float across the eyes which are induced because of material in the vitreous gel of the eye
An unusual symptom and one that can indicate the presence of other diseases is any difference seen in photographs taken with a flash and where the eyes do not give the same configuration of “camera red eye”.
What causes it?
Autoimmune disorders such as HIV, tuberculosis and congenital toxoplasmosis (an infection caught when young through exposure to cat faeces) can be a precursor to suffering from the disease.
Although the exposure may occur early in life the disease may lie dormant for many years.
The first step is to organise an effective treatment plan for any underlying auto immune cause.
The second step is to reduce the inflammations – anti-inflammatory steroids can be prescribed to be taken orally or more usually in eye drop form. In severe cases injections in the surrounding eye areas may be required.
If an infection is thought to have caused the inflammation then a course of antibiotics will need to be followed – UNTIL THE COURSE IS FINISHED. Far too often patients do not complete a full course of treatment in antibiotics after symptoms begin to disappear.
In the case of children it’s necessary to take precautions to make sure other senses are not impaired, and consultations should be organised with several medical professionals:
• An Audiologist – to measure any deterioration in hearing
• A Neurologist – to examine brain behaviour
• A Physiotherapist – to monitor muscle control and joint movements
Genetic testing may in the future provide more answers.