What Is the Retina and How Does It Function?
Light enters through the front of the eye (cornea, pupil, and lens) and focuses on the retina. The retina is a thin neurosensory layer of tissue that lines the back of your eye. Its sole purpose is to convert light information into electrical signals for the brain to understand.
It has a matrix of blood vessels to supply oxygen to the retina.
The retina has two main functional areas; divided into the macula: central vision for colour perception, detailed high resolution vision. The second area being the mid/peripheral retina for its responsibility in the peripheral vision and detecting movement as well ability to see in low light levels.
What Is a Retinal Detachment?
When your retina separates from the wall of your eye, it is known as a Retinal Detachment.
Your retina needs to be attached inside your eye to stay healthy and work properly. It can cause permanent sight loss if it remains detached and untreated, as the retina is no longer able to send electric signals to the brain.
Most retinal detachments are as a result of a retinal tear or hole which has been caused by the vitreous jelly pulling on the retina. Once there is a tear or hole, fluid can build up behind the retina causing it to detach further.
In diabetic patients or after eye trauma, tractional detachment may occur. This is when scar tissue develops on the surface of the retina, pulling it away and detaching it. This can happen without a tear or hole.
What Are the Symptoms of a Retinal Detachment?
Retinal detachment itself is painless. But warning signs can appear before it occurs or has advanced, including:
Sudden appearance of or increase in floaters — tiny black spots that seem to drift through your field of vision
A progressive curtain-like shadow over your field of vision
Flashes of light in one or both eyes (photopsiae)
If experienced, patients need to undergo a full retinal examination through dilated pupils which includes a slit-lamp Biomicroscopy and Indirect Ophthalmoscopy with scleral indentation.
Who Is More Likely to Get a Retinal Detachment?
Retinal Detachments caused by tears can happen in approximately 1 in 10,000 people per year and can occur at any age.
You may be at higher risk of developing a Retinal Detachment if you:
- Have a symptomatic Posterior Vitreous Detachment
- Have a history of Retinal Detachment in the other eye
- Have weak areas in your retina
- Have had previous cataract surgery
- Are short-sighted
- Have a family history of retinal detachment
What Is the Treatment for Retinal Detachment?
Retinal tears or holes, which occur before a retinal detachment, can sometimes be treated with laser therapy or cryotherapy (freezing) to prevent their evolution into a Retinal Detachment.
Once the retina has detached, there are three possible surgical treatment options to reattach the retina: vitrectomy, scleral buckling and pneumatic retinopexy.
Small peripheral Retinal Detachments with no symptoms can sometimes be “walled off” with laser treatment to prevent further expansion.
Prof Stanga will discuss with you the best course of action in your consultation and explain the risks and benefits to the choice of treatment.