Retinal detachment occurs when the thin, light-sensitive layer at the back of the eye pulls away from its underlying supporting tissue. In adults, this separation is rarely the result of a single event but is instead the culmination of various physiological changes, underlying health conditions, or external factors. Because the retina cannot function without its connection to the blood vessels that provide oxygen and nutrients, identifying the causes is a critical component of preventative eye care. Most cases in the UK are related to the natural ageing process of the eye, although certain systemic diseases and lifestyle factors can significantly increase the likelihood of a detachment occurring.
What We’ll Discuss in This Article
- The role of age-related vitreous changes in causing retinal tears.
- How severe short-sightedness increases the risk of retinal thinning.
- The impact of diabetic retinopathy on tractional detachment.
- How physical trauma and eye injuries can trigger a separation.
- The influence of previous eye surgeries on retinal stability.
- Inflammatory conditions and tumours as causes of fluid buildup.
- Genetic predispositions and pre-existing retinal weaknesses.
Age-related changes and vitreous detachment
The most common cause of retinal detachment in adults is the natural ageing of the eye, specifically changes within the vitreous humour. The vitreous is a clear, jelly-like substance that fills the space between the lens and the retina, helping the eye maintain its spherical shape. As an individual ages, the vitreous becomes more liquid and begins to shrink. This process often leads to a posterior vitreous detachment (PVD), where the gel pulls away from the retinal surface. In most cases, this occurs without incident, but sometimes the gel remains firmly attached to certain areas.
When the shrinking vitreous tugs on these points of attachment, it can create a retinal tear or hole. Once a break in the tissue exists, the liquefied vitreous can seep through the opening and accumulate behind the retina. This fluid creates pressure that gradually peels the retina away from the back of the eye. This sequence of events is the primary driver for rhegmatogenous retinal detachment, the most frequent type seen in clinical settings. According to the NHS overview of retinal detachment causes, these age-related changes are the leading reason why the condition is more prevalent in adults over the age of fifty.
High myopia and retinal thinning
Severe short-sightedness, known as high myopia, is a major contributing factor to retinal detachment in adults. In a myopic eye, the eyeball is physically longer than normal, which causes light to focus in front of the retina rather than directly on it. This elongated shape means that the retinal tissue is stretched more thinly across the inner surface of the eye. Because the tissue is thinner, it is inherently more fragile and prone to developing small holes or peripheral degenerations, such as lattice degeneration.
Adults with high myopia often experience vitreous changes earlier in life than those with normal vision. The combination of a stretched, thin retina and an early-onset liquefaction of the vitreous creates a high-risk environment for tears. Clinical guidelines, including those found in NICE clinical knowledge summaries on eye health, emphasise that myopic patients require regular monitoring of their peripheral retina. Early detection of thinning or asymptomatic tears in these individuals can allow for preventative laser treatment, which seals the retina to the back of the eye and reduces the chance of a full detachment.
Diabetic retinopathy and tractional causes
For many adults, retinal detachment is a secondary complication of chronic systemic health issues, most notably diabetes. Diabetic retinopathy occurs when high blood sugar levels cause damage to the tiny blood vessels in the retina. In advanced stages, known as proliferative diabetic retinopathy, the eye attempts to compensate for a lack of oxygen by growing new, abnormal blood vessels. These vessels are fragile and prone to leaking blood into the vitreous.
Over time, this bleeding and subsequent healing process lead to the formation of fibrous scar tissue on the surface of the retina. As this scar tissue contracts, it exerts a “tractional” force, physically pulling the retina away from the eye wall. Unlike the tears caused by vitreous changes, tractional retinal detachment does not necessarily involve a hole in the retina; rather, it is the result of external mechanical pulling. Managing blood glucose levels and attending regular diabetic eye screening are the primary methods for preventing this form of detachment in the UK.
Physical trauma and eye injuries
Direct trauma to the eye or a significant blow to the head can cause the retina to detach suddenly. The force of an impact can cause a rapid deformation of the eyeball, leading to a sudden shift in the vitreous gel. This jarring motion can rip the retina away from its base or create large tears known as giant retinal tears. While trauma can affect individuals of any age, it is a notable cause in active adults or those in certain industrial occupations.
Even if a detachment does not occur immediately after an injury, the trauma can cause the vitreous to become unstable, leading to a detachment weeks or even months later. This is why UK clinical practice dictates that any significant eye injury should be followed by a dilated fundus examination by an optometrist or ophthalmologist. Promptly identifying a post-traumatic tear can prevent the subsequent accumulation of fluid that leads to a clinical detachment.
Previous eye surgeries and complications
Adults who have undergone certain types of eye surgery may be at a slightly increased risk of developing a retinal detachment. For example, while cataract surgery is a highly successful and common procedure in the UK, it involves changes to the internal pressure and structure of the eye. In a small percentage of cases, these changes can accelerate the liquefaction of the vitreous or lead to a posterior vitreous detachment, which may eventually cause a retinal tear.
Other procedures, such as those involving the vitreous itself (vitrectomy) or surgeries to treat glaucoma, can also influence the stability of the retinal attachment. However, it is important to note that the risk is relatively low, and the benefits of these surgeries usually far outweigh the potential for complications. Patients are typically advised on the specific symptoms to watch for following surgery to ensure that any issues are caught in the earliest possible stages.
Inflammation and rare causes
In a small number of cases, retinal detachment is caused by fluid buildup behind the retina without any physical tear or traction. This is known as exudative retinal detachment. The primary causes in adults include inflammatory diseases like sarcoidosis or uveitis, which cause the blood vessels to become “leaky.” Certain tumours, such as a choroidal melanoma, can also cause fluid to seep into the space beneath the retina, gradually pushing it away from the eye wall. These cases require a different diagnostic approach, focusing on treating the underlying inflammation or growth rather than just the mechanical detachment of the retina.
| Cause Type | Primary Mechanism | Typical Patient Profile |
| Ageing (PVD) | Vitreous pulling and tearing | Adults over 50 |
| High Myopia | Retinal thinning and stretching | Highly short-sighted adults |
| Diabetes | Scar tissue contraction (Traction) | Long-term diabetic patients |
| Trauma | Impact causing sudden tears | Active adults, eye injuries |
Conclusion
The main causes of retinal detachment in adults range from the natural ageing of the eye to complications from high myopia and diabetes. While age-related vitreous changes are the most common trigger, systemic health and physical injury also play significant roles. Understanding these causes helps in identifying those at higher risk and reinforces the importance of regular eye check-ups. If you experience severe, sudden, or worsening symptoms, call 999 immediately.
Is retinal detachment always caused by a tear?
No, while most are caused by tears, some are caused by scar tissue pulling the retina or fluid leaking behind it due to inflammation.
Does family history increase the risk?
Yes, some individuals have a genetic predisposition to thinner retinal tissue, which can increase the risk of detachment.
Can heavy lifting cause retinal detachment?
In people who already have a retinal tear, extreme physical strain can potentially accelerate a detachment, but it is rarely the sole cause in a healthy eye.
How does high blood pressure affect the retina?
Very high blood pressure can damage retinal blood vessels, occasionally leading to fluid leakage or exudative detachment.
Are floaters always a sign of a detachment cause?
Not always; floaters are often harmless signs of ageing vitreous, but a sudden increase can signal a tear.
Does smoking increase the risk of retinal detachment?
Smoking is linked to many eye diseases that can weaken ocular health, though it is not a direct mechanical cause of detachment
Can a detachment occur in both eyes at once?
It is possible, but it usually occurs in one eye. However, the underlying cause (like myopia or age) often exists in both eyes.
Authority Snapshot
This article provides an evidence-based overview of the causes of retinal detachment for adult patients. The content is written and reviewed by the Medical Content Team and Dr. Rebecca Fernandez, ensuring alignment with UK healthcare standards. All information is strictly based on NHS guidance on retinal health and NICE standards to provide accurate and safe health information.
