Retinal Detachment: Symptoms, Causes and How Eye Ultrasound Can Help
Retinal detachment is one of the most important eye conditions patients should know about because it can threaten vision if not treated quickly. It may begin with subtle symptoms such as new floaters, flashing lights or blurred vision, but it can progress to a dark shadow or curtain moving across the vision.
This patient-friendly guide explains what retinal detachment is, the urgent warning signs, why it happens, how it is diagnosed, and how ocular B-scan ultrasound can help when the back of the eye cannot be clearly seen.
Urgent Warning
If you develop sudden floaters, flashing lights, sudden blurred vision, sudden loss of vision, or a dark curtain or shadow in your vision, seek urgent same-day eye assessment. Retinal detachment can be painless, so absence of pain does not mean the condition is harmless.
If symptoms follow eye trauma, or if you have severe eye pain or sudden vision loss, seek urgent ophthalmology or emergency care immediately.
Quick Answer: What Is Retinal Detachment?
Retinal detachment occurs when the retina separates from the supportive tissue at the back of the eye. The retina depends on this underlying tissue for oxygen and nutrients. When it detaches, vision may become blurred, shadowed, distorted or lost.
Eye ultrasound, also called ocular B-scan ultrasound, may help when the retina cannot be clearly examined because of vitreous haemorrhage, dense cataract, trauma-related media opacity or poor visibility through the eye.
What Is the Retina?
The retina is a thin, delicate layer of nerve tissue lining the back of the eye. Its job is to detect light and convert it into electrical signals. These signals travel through the optic nerve to the brain, where they are interpreted as vision.
The retina is essential for:
- Central vision
- Peripheral vision
- Reading
- Recognising faces
- Seeing colour
- Detecting movement
- Navigating surroundings
- Seeing fine detail
The central part of the retina is called the macula. The macula is responsible for sharp central vision, including reading, driving and seeing fine detail.
Why Is Retinal Detachment an Emergency?
Retinal detachment is considered an eye emergency because vision can deteriorate if treatment is delayed. The outcome often depends on how much retina is detached, whether the macula is involved, how quickly treatment is provided, the underlying cause and whether there are other eye conditions.
If the macula is still attached, urgent treatment may help preserve central vision. If the macula becomes detached, visual recovery may be more limited, even after successful surgery.
What Are the Warning Signs of Retinal Detachment?
You should seek urgent medical or ophthalmology assessment if you experience:
- A sudden increase in floaters
- New flashing lights
- A dark curtain or shadow in your vision
- Sudden blurred vision
- Sudden loss of peripheral vision
- A missing area in your vision
- New symptoms after eye trauma
- Sudden vision change in one eye
These symptoms should not be ignored, even if there is no pain.
What Are Floaters?
Floaters are small shapes that appear to drift across your vision. They are commonly caused by changes in the vitreous gel inside the eye.
Floaters may look like:
- Dots
- Threads
- Cobwebs
- Flies
- Rings
- Shadows
- Specks
- Small drifting shapes
Occasional long-standing floaters are common, but a sudden shower of new floaters may indicate bleeding or a retinal tear and should be assessed urgently.
What Are Flashes?
Flashes are brief bursts of light seen in the vision. They can occur when the vitreous gel pulls on the retina. This traction can sometimes cause a retinal tear.
Flashes may look like:
- Lightning streaks
- Sparkles
- Camera flashes
- Flickering light
- Arcs of light at the side of vision
- Brief bursts of light
What Causes Retinal Detachment?
There are several types of retinal detachment. The most common is rhegmatogenous retinal detachment. This occurs when a tear or hole develops in the retina and fluid passes underneath it, separating the retina from the underlying tissue.
Rhegmatogenous Retinal Detachment
This is the most common type. It occurs when a retinal tear allows fluid to pass under the retina.
Tractional Retinal Detachment
This occurs when scar tissue pulls the retina away from the back of the eye. It is often associated with advanced diabetic eye disease.
Exudative Retinal Detachment
This occurs when fluid accumulates under the retina without a tear. It may be associated with inflammation, tumours or vascular disease.
The Pathophysiology of Retinal Detachment
To understand retinal detachment, imagine the retina as delicate wallpaper lining the inside of the eye. Normally, it sits closely against the back wall of the eye. It is held in position by natural pressure, fluid balance and close contact with the retinal pigment epithelium.
As the eye ages, the vitreous gel inside the eye becomes more watery and may shrink. When it separates from the retina, this is called posterior vitreous detachment. In most people this is harmless, but if the vitreous remains strongly attached to one part of the retina, it may pull hard enough to create a tear.
- Fluid from inside the eye can pass through the retinal break.
- The fluid collects behind the retina.
- The retina begins to lift away from the back wall of the eye.
- The detached retina loses normal support and nourishment.
- Vision becomes blurred, shadowed, distorted or lost.
Who Is at Higher Risk?
Retinal detachment can happen in different groups of patients, but some risk factors make it more likely.
- Increasing age
- Short-sightedness, especially high myopia
- Previous retinal tear
- Previous retinal detachment in the other eye
- Previous cataract surgery
- Eye trauma
- Family history of retinal detachment
- Diabetic eye disease
- Inflammatory eye disease
- Certain inherited retinal conditions
Patients with these risk factors should take new floaters, flashes or vision changes especially seriously.
Retinal Detachment After Cataract Surgery
Most cataract surgery is safe and successful. However, previous cataract surgery can slightly increase the risk of retinal detachment in some patients, especially those who are highly short-sighted or have other risk factors.
- New floaters after cataract surgery
- Flashing lights
- Sudden shadow
- Sudden blurred vision
- Peripheral field loss
Retinal Detachment and Diabetes
People with advanced diabetic retinopathy may develop abnormal blood vessels and scar tissue inside the eye. This scar tissue can contract and pull on the retina, leading to tractional retinal detachment.
Diabetic patients with sudden blurred vision, floaters or reduced vision should seek prompt eye assessment.
Retinal Detachment After Trauma
Blunt or penetrating eye injury can cause retinal tears, vitreous haemorrhage, lens dislocation, retinal detachment or internal eye damage.
After trauma, urgent eye assessment is essential. Eye ultrasound may be useful only when the eye is intact. If an open globe injury is suspected, ultrasound should not be performed unless an appropriate eye specialist confirms it is safe.
How Is Retinal Detachment Diagnosed?
Diagnosis usually involves urgent eye assessment. The exact tests depend on symptoms and examination findings.
Visual Acuity Test
Checks how well you can see.
Pupil Examination
Assesses the eye’s response to light.
Dilated Retinal Examination
Eye drops widen the pupil so the retina can be examined.
Slit-Lamp Examination
A specialist microscope is used to examine the eye.
Optical Coherence Tomography
OCT may assess the macula if the view is clear enough.
Ocular Ultrasound
B-scan ultrasound may be used when the retina cannot be clearly seen.
When Is Eye Ultrasound Useful?
Eye ultrasound is particularly useful when the back of the eye cannot be examined directly.
This may happen due to:
- Vitreous haemorrhage
- Dense cataract
- Corneal opacity
- Severe inflammation
- Poor view through the pupil
- Trauma-related media opacity
- Inability to visualise the retina properly
- Poor retinal view
In these cases, ocular B-scan ultrasound can help assess whether the retina appears attached or detached.
What Can Eye Ultrasound Show in Retinal Detachment?
Ocular B-scan ultrasound may show internal eye abnormalities when direct viewing is limited.
- A detached retinal membrane
- Vitreous haemorrhage
- Posterior vitreous detachment
- Intraocular membranes
- Lens displacement
- Some intraocular masses
- Signs of trauma-related internal abnormality
- Features supporting urgent ophthalmology referral
A retinal detachment may appear as a bright, folded membrane within the eye, often tethered at characteristic points.
Can Ultrasound Detect All Retinal Tears?
No. This is important for patient safety.
Ultrasound can be very helpful for detecting retinal detachment, especially when the view is poor. However, small retinal tears may not always be visible on ultrasound.
If you have symptoms of a retinal tear or retinal detachment, you still need urgent specialist eye assessment, even if ultrasound findings appear reassuring. Eye ultrasound is a supportive investigation, not a replacement for a full retinal examination.
What Is Vitreous Haemorrhage and Why Does It Matter?
Vitreous haemorrhage means bleeding into the gel inside the eye. Blood in the vitreous may block the doctor’s view of the retina. In this situation, ultrasound can help assess whether there is an underlying retinal detachment.
Vitreous haemorrhage may happen due to:
- Retinal tear
- Diabetic retinopathy
- Retinal vein occlusion
- Trauma
- Abnormal fragile blood vessels
What Happens If Retinal Detachment Is Found?
If retinal detachment is suspected or confirmed, urgent ophthalmology referral is needed. Treatment depends on the type, size, location and severity of the detachment.
Laser Treatment
Used for some retinal tears before detachment progresses.
Cryotherapy
Freezing treatment may seal some retinal breaks.
Pneumatic Retinopexy
A gas bubble is injected into the eye in selected cases.
Vitrectomy
The vitreous gel is removed and the retina is repaired.
Scleral Buckle Surgery
A silicone band is placed around the eye to support the retina.
Urgent Referral
Final management should be guided by an ophthalmology specialist.
Can Vision Be Restored After Retinal Detachment?
Many patients recover useful vision after successful treatment, but outcomes vary.
Factors affecting recovery include:
- Whether the macula detached
- How long the retina was detached
- Severity of detachment
- Presence of other eye disease
- Surgical success
- Patient age and eye health
Early treatment generally gives the best chance of preserving vision.
What Should You Do If You Suspect Retinal Detachment?
- Do not wait for symptoms to improve.
- Seek urgent same-day eye assessment.
- Contact NHS 111, an urgent optometry service, eye casualty or emergency care.
- Avoid driving if vision is affected.
- Explain clearly that you have sudden floaters, flashes, shadow or vision loss.
- Ask whether urgent retinal examination is required.
If you already have known retinal disease or previous retinal detachment, act quickly.
Private Eye Ultrasound in London
At London Private Ultrasound, ocular ultrasound may be used to assess selected eye conditions where imaging of the internal eye structures is clinically appropriate.
Eye ultrasound may be helpful in cases involving:
- Poor retinal view
- Suspected retinal detachment
- Vitreous haemorrhage
- Dense cataract blocking the view
- Certain trauma-related concerns where the globe is intact
- Posterior eye abnormalities requiring B-scan assessment
- Book a private eye ultrasound scan in London
- View London Private Ultrasound price list
- Contact London Private Ultrasound
Important: If you have sudden vision loss, severe eye pain, a dark curtain or shadow, or symptoms after trauma, seek urgent ophthalmology or emergency assessment immediately. Do not delay urgent care while waiting for a routine appointment.
Frequently Asked Questions
Is retinal detachment painful?
Usually, retinal detachment is painless. This is why symptoms such as floaters, flashes, shadows or sudden blurred vision are so important.
Can retinal detachment happen slowly?
Yes. Some detachments progress gradually, but others worsen quickly. Any new shadow, curtain or visual field loss should be treated as urgent.
Can an ultrasound confirm retinal detachment?
Ultrasound can strongly support the diagnosis, particularly when the retina cannot be seen directly. However, final management should be guided by ophthalmology assessment.
Does a normal ultrasound rule out a retinal tear?
No. Small retinal tears may be missed on ultrasound. Patients with symptoms still need urgent retinal examination.
Should I book an ultrasound first or see an eye specialist first?
If you have sudden floaters, flashes, blurred vision or a dark curtain or shadow, seek urgent eye assessment first. Ultrasound may be arranged if clinically needed.
Final Thoughts
Retinal detachment is a serious eye condition that can threaten vision if not treated quickly. Warning signs include sudden floaters, flashing lights, sudden blurred vision and a dark curtain or shadow moving across the vision.
Eye ultrasound is a valuable investigation when the retina cannot be clearly seen, particularly in the presence of vitreous haemorrhage, dense cataract or poor retinal view. It can help detect retinal detachment and support urgent referral decisions.
However, ultrasound does not replace specialist retinal examination, and small retinal tears may not always be visible.
If you develop sudden floaters, flashes, vision loss or a shadow in your vision, seek urgent ophthalmology or emergency assessment immediately.
Book a Private Eye Ultrasound Scan in London
London Private Ultrasound provides private ocular B-scan ultrasound for selected eye conditions where internal eye imaging is clinically appropriate.
References
Article Preparation and Clinical Review
This patient information page was prepared with AI-assisted editorial support and reviewed for clinical accuracy by:
Dr Pedram Aghaei — Vascular Scientist, SVT reg. SVT 679 · Registered Clinical Technologist, RCT reg. 93290 · BMUS 20702
Dr Hosna Rashidi — BMUS 29386 · SVT reg. M11114