Last Friday I attended the Eye casualty department of the Prince Charles Eye Unit, part of the King Edward VII Hospital in Windsor.
I had been getting peripheral flashing in the upper and right sections of my right eye. I've had cataracts dealt with in both eyes and wondered if perhaps the lens had somehow shifted and light was catching the edge giving the impression of a flash.
It wasn't that at all, it was yet another indication of years passing by and the vitreous gel inside my eye taking up less space within the eye and causing movement against the retina.
After a thorough check, sight test and scans of both eyes, there were no serious nor long term problems discovered. I was diagnosed as having PVD Posterior Vitreous Detachment. They gave me a fact sheet to read, a slightly different version is shown below.
If you have a major problem with floaters, dark patches, or anything else associated with sudden troubled vision, please get your eyes checked without delay.
This is the fact sheet I've downloaded :
We have written this factsheet to explain what posterior vitreous detachment (PVD) is,
what signs and symptoms to look out for, and what the potential risks of the condition
are. We hope it will help to answer some of the questions you may have. If you have
any further questions or concerns, please speak to a member of your healthcare team.
What is PVD?
The eye is like a camera with a lens at the front and a light-sensitive film (the retina) at the
back. Filling the space between these is a clear jelly-like tissue called the vitreous.
As we get older, the jelly-like vitreous becomes more like a liquid gel and collapses in on
itself, pulling away from the retina. Small opacities (unclear areas) may form in the gel and
as it starts to move around in the eye, these can be seen as ‘floaters’ in your vision (often
described as flies, spiders and cobwebs).
What causes PVD?
PVD is more common in people over the age of 60. This is because the texture of the vitreous
naturally changes as you get older. In 90% of people this change is usually harmless and
causes no damage to the retina. PVD is a once-in-a-lifetime event and cannot be prevented.
How is PVD diagnosed?
To diagnose PVD, an ophthalmologist (a specialist eye doctor), an optician or a nurse
practitioner will put eye drops into your eye to dilate (enlarge) your pupil. They will then look at
the middle and the back of your eye with a microscope to check the vitreous.
These eye drops will blur your vision for approximately three to four hours. You must not drive
while your vision is affected.
What are the signs and symptoms of PVD?
Mild floaters in your vision can be normal. However, if you have PVD you will usually notice:
• a sudden increase in floaters
• flashing lights like little flickers or streaks of light at the edges of your vision (more
noticeable in the dark)
PVD on its own will not permanently affect your eyesight.
Are there any risks associated with PVD?
Retinal detachment
Occasionally, when the vitreous pulls away from the retina, it pulls so hard that it tears the
retina. This happens in less than one in ten people who develop PVD. This can then lead to a
retinal detachment (when the retina becomes loose). If your retina becomes loose, you may
experience a black shadow and/or loss of vision, and you will require urgent surgical treatment.
A retinal tear (without retinal detachment) will require urgent laser treatment or cryotherapy (a
freezing treatment).
Epiretinal membrane
When the vitreous pulls away from the retina, it can cause a thin, clear layer of tissue (a
membrane) to form on the surface of the retina. This membrane can cause the retina to become wrinkled, and your vision may become distorted and blurred. If your vision is very
distorted, we may recommend you have surgery.
Do the flashes and floaters ever stop?
Generally the flashes stop after a few months and do not cause any problems.
The floaters are very obvious when they first appear. Over time they become much less
noticeable and do not cause a visual problem in most people.
You can reduce the effect of floaters by wearing dark glasses, especially if you are out in
bright sunlight, or if you are looking at a brightly-lit surface or background.
Is there anything I should look out for?
Contact our eye casualty department as soon as possible if your symptoms become worse or
if you notice any of the following:
• an increase in floaters and/or flashing lights
• a black shadow or ‘curtain’ coming over your vision
• your vision suddenly getting worse
Contact us
Eye casualty
Telephone: 023 8120 6592 (24-hour service)
Useful links
www.rnib.org.uk/eye-health/eye-conditions/posterior-vitreous-detachment
www.rcophth.ac.uk/wp-content/uploads/2017/10/2017_Understanding-Posterior-vitreous-
detachment.pdf
www.specsavers.co.uk/eye-health/posterior-vitreous-detachment
Version 3. Published September 2020. Due for review September 2023. 2616
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as easy read, large print, Braille or audio, please telephone
0800 484 0135 or email patientsupporthub@uhs.nhs.uk
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the hospital, please visit www.uhs.nhs.uk/additionalsupport
