What a retinal detachment is
The retina is the thin, light-sensitive lining at the back of the eye that captures what you see. Normally it lies flat against the inner wall of the eye, like wallpaper smoothly attached to a wall. A retinal detachment is when a section of that lining lifts away from the wall. Where the retina is lifted, it can no longer work, and that part of your vision goes dark.
Most detachments begin with a small break or retinal tear. Fluid from inside the eye passes through the break and collects behind the retina, peeling it away much as water seeping under a loose tile lifts it from the floor. Once this starts it tends to spread, which is why time matters so much.
A retinal detachment: the retina lifting away from the wall of the eye.
The four warning signs to know
A retinal detachment does not hurt, so there is no pain to warn you. The signs are entirely visual, and they often appear in a recognisable sequence. If you notice any of them, treat it as an emergency.
- A sudden burst of new floaters, often many small dark specks appearing at once
- Flashes of light, usually at the edge of vision and most noticeable in dim surroundings
- A dark shadow, curtain, or veil spreading across part of your vision from one side
- A loss or blurring of central vision, which suggests the detachment has reached the most important part of the retina
The shadow or curtain is the most important of these. It means the retina is already lifting, and that the detachment is progressing. A curtain that is spreading is a reason to seek help immediately, not in the morning.
Flashes of light in one eye often come before the shadow. Do not wait for the shadow to appear.
Why acting quickly matters so much
The single most important factor in the outcome of a retinal detachment is whether the central retina, called the macula, is still attached when treatment happens. While the macula is still on, the detailed central vision can usually be preserved. Once the detachment spreads to lift the macula, that fine central vision is at serious risk even after successful surgery.
This is why a detachment is genuinely time-critical. The window between the first symptoms and the macula being affected can be short, sometimes only a day or two, and occasionally less. Seeking assessment the same day, rather than waiting to see whether things settle, is what protects your sight.
Who is at higher risk
Anyone can develop a retinal detachment, but some people carry a higher risk and should be especially alert to the warning signs. Short-sightedness (myopia) is the most significant factor, because the retina is thinner and more stretched in a longer eye. A previous detachment in either eye, a family history of detachment, previous cataract or other eye surgery, a significant eye injury, and a thinning of the peripheral retina called lattice degeneration all increase the risk.
If you fall into one of these groups and you develop new floaters or flashes, it is particularly important not to dismiss them.
What to do if you notice these signs
Do not wait for a routine appointment, and do not wait overnight if symptoms appear in the evening. Contact your nearest eye casualty or urgent eye care service, attend an accident and emergency department, or call NHS 111 for urgent ophthalmology advice. Explain that you have sudden new floaters, flashes, or a shadow in your vision and that you are concerned about a possible retinal detachment.
There is nothing useful you can do at home to slow a detachment, so the priority is simply to be seen and examined quickly. It is always better to be checked and reassured than to wait and lose the window for treatment.
How retinal detachment is treated
A detachment that has already happened needs an operation to put the retina back in place. There are several techniques, and the choice depends on the type and position of the detachment. They include vitrectomy, in which the gel is removed and the retina settled back against the wall of the eye, the placement of a small silicone band around the eye called a scleral buckle, and in selected cases an injection of gas that presses the retina back into position.
When a detachment is treated before it reaches the macula, the outlook for vision is generally good. This, once again, is why the warning signs are worth knowing and acting on without delay.
In summary
- A retinal detachment is the light-sensitive lining lifting away from the wall of the eye
- It is painless, so the warning signs are entirely visual
- The four signs are new floaters, flashes, a spreading shadow or curtain, and loss of central vision
- A spreading shadow is the most urgent sign and means the detachment is progressing
- Outcome depends heavily on being treated before the central retina is affected
- Treat any of these signs as a same-day emergency: eye casualty, A&E, or NHS 111
Learn more about floaters and the retina
Floaters explained →Common questions
Is retinal detachment painful?
No. A retinal detachment is painless, because the retina has no pain receptors. This is precisely why it is so important to recognise the visual warning signs, since there is no pain to alert you that something serious is happening.
How quickly does retinal detachment happen?
It varies. Some detachments spread over hours, others over a few days. Because the outcome depends so heavily on treating it before the central retina is involved, and because you cannot predict the speed, the safe assumption is always that it is urgent and needs same-day assessment.
Can retinal detachment be fixed?
In most cases, yes. Surgery to reattach the retina is successful in the great majority of detachments, especially when treatment happens early. The key factor is timing: the sooner it is treated, particularly before the central retina lifts, the better the result.
Will my vision come back after surgery?
It depends largely on whether the central retina was affected before surgery. If the detachment was treated while central vision was still intact, the outlook is generally good. If the central retina had already lifted, some vision can return but it may not be fully restored, which is why acting on the early signs matters so much.
What does the shadow from a retinal detachment look like?
People describe it as a dark curtain, veil, or shadow coming across the vision from one side, from above, or from below. It tends to grow over hours rather than staying still. A spreading shadow of this kind is one of the most urgent eye symptoms there is, and it warrants immediate assessment.
This page is for general educational purposes and does not constitute medical advice. If you are concerned about your vision, please seek same-day assessment from a qualified eye care professional. Last reviewed May 2026 by Chris Matthews, Consultant Ophthalmologist.
