Steroid injections are an effective and widely used treatment for diabetic macular oedema (DMO) in the United Kingdom. While anti-VEGF injections are typically the first-line therapy, steroids play a crucial role for patients who do not respond well to other treatments or for those who cannot have anti-VEGF drugs. Instead of a liquid injection that requires monthly visits, steroids for the eye are often delivered via tiny, slow-release implants. These implants are designed to sit inside the eye and release medication over several months or even years, helping to reduce inflammation and “dry up” the fluid that causes central vision blurring.
What We’ll Discuss in This Article
- The two primary types of steroid implants used by the NHS.
- NICE criteria for transitioning from anti-VEGF to steroid therapy.
- Why steroids are particularly effective for “chronic” or inflammatory swelling.
- The specific risks associated with steroids, including cataracts and glaucoma.
- The difference between phakic and pseudophakic (artificial lens) eligibility.
- What to expect during and after a steroid implant procedure.
Types of Steroid Implants in the UK
In the NHS, steroids are usually administered as sustained-release implants rather than traditional liquid injections. This is because steroids are most effective when they provide a steady, long-term dose of anti-inflammatory medication directly to the retina.
- Dexamethasone (Ozurdex): This is a biodegradable implant that slowly dissolves in the eye. It typically releases medication for up to six months. It is often used when a patient’s swelling has not responded sufficiently to an initial course of anti-VEGF injections.
- Fluocinolone Acetonide (Iluvien): This is a non-biodegradable, tiny tube that releases a very small daily dose of steroid for up to three years. According to NICE guidance (TA301), Iluvien is specifically recommended for “chronic” diabetic macular oedema that has not responded well enough to other available therapies.
NICE Criteria for Steroid Treatment
The National Institute for Health and Care Excellence (NICE) has established clear pathways for when a specialist should consider steroids. Generally, steroids are recommended as a “second line” option.
A specialist may decide to use a steroid implant if:
- Inadequate Response: Your vision or retinal thickness has not improved after a standard course (usually 6 months) of anti-VEGF injections.
- Treatment Burden: You find it difficult to attend the frequent hospital appointments required for monthly anti-VEGF injections.
- Medical Contraindications: You have a medical history (such as a recent major cardiovascular event) that makes anti-VEGF therapy unsuitable.
Historically, steroids were primarily reserved for “pseudophakic” patients (those who have already had cataract surgery), but NICE updated its guidelines in 2022 to allow the use of dexamethasone implants in “phakic” patients (those with their natural lens) if other treatments are unsuitable.
Why Steroids Work Differently
While anti-VEGF drugs block the specific chemical signal that causes vessel leaks, steroids have a broader “anti-inflammatory” effect. In chronic diabetes, the swelling in the macula is often driven by a wide range of inflammatory molecules, not just VEGF. Steroids help to stabilize the blood-retinal barrier and reduce this broad inflammation.
Clinical data from Manchester University NHS Foundation Trust indicates that steroids can be exceptionally effective at drying up persistent fluid that has resisted other treatments. Because they last longer in the eye, they can also provide a “smoother” treatment experience with fewer fluctuations in vision between clinic visits.
Associated Risks: Glaucoma and Cataracts
The most significant drawback of using steroids in the eye is the increased risk of two specific side effects. Specialists monitor for these very closely during follow-up appointments:
- Steroid-Induced Glaucoma: Steroids can cause a rise in the pressure inside the eye (intraocular pressure). While this is usually manageable with daily eye drops, a small percentage of patients may require more intensive treatment if the pressure rise is significant.
- Cataracts: Steroids significantly accelerate the clouding of the eye’s natural lens. For most patients who receive long-term steroid treatment, a cataract operation will eventually be necessary. This is why steroids were historically preferred for patients who had already had their cataracts removed.
What to Expect During the Procedure
The process for receiving a steroid implant is very similar to a standard eye injection. The eye is thoroughly numbed with anaesthetic drops and cleaned with an antiseptic solution to prevent infection. The implant is then injected through the white part of the eye (the sclera) using a specialized applicator.
After the procedure, you may notice a “floater” in your vision, which is simply the shadow of the implant itself drifting in the vitreous gel. This usually settles as the implant moves toward the bottom of the eye. According to Guy’s and St Thomas’ NHS Foundation Trust, you should avoid getting water in your eye or swimming for at least five days after the injection to ensure the site heals correctly.
| Feature | Ozurdex (Dexamethasone) | Iluvien (Fluocinolone) |
| Duration of Action | Up to 6 months | Up to 3 years |
| Implant Type | Biodegradable (Dissolves) | Non-biodegradable (Remains) |
| NICE Recommendation | Inadequate anti-VEGF response | Chronic DMO / Insufficient response |
| Primary Side Effect | Pressure rise / Cataracts | Higher risk of pressure rise |
| UK Availability | Widely available in the NHS | Restricted to chronic cases |
Conclusion
Steroid injections, typically delivered as long-acting implants like Ozurdex or Iluvien, are a vital treatment option for diabetic macular swelling in the UK. They are particularly effective for chronic inflammation that does not respond to anti-VEGF therapy. While they offer the benefit of fewer hospital visits, they do carry a higher risk of cataracts and increased eye pressure. Specialists carefully weigh these factors to decide if a steroid implant is the right choice for your specific stage of retinopathy. If you experience severe, sudden, or worsening symptoms, call 999 immediately.
Will a steroid injection fix my vision immediately?
No, it usually takes several weeks for the swelling to subside. You may notice a gradual improvement in clarity or a reduction in wavy lines over the first month.
Do I still need to have my eye pressure checked?
Yes, it is essential. You will typically be seen 4 to 6 weeks after a steroid injection specifically to check your intraocular pressure.
Can I have steroid implants in both eyes?
Yes, if both eyes have macular swelling, but they are usually treated at separate appointments to ensure your vision is maintained in at least one eye at all times.
What happens to the Iluvien tube after 3 years?
The tiny tube is non-biodegradable and remains in the eye. It is very small and does not usually cause any issues once the medication has been fully released.
Why did my doctor suggest cataract surgery before the steroid?
If you already have a mild cataract, the steroid will likely make it worse quite quickly. Many surgeons prefer to remove the cataract first so that the steroid can be used more safely.
Can steroids cause an infection?
Any injection into the eye carries a very small risk of infection (endophthalmitis). This is why antiseptic is used and why you must report any severe pain or sudden redness.
Does Ozurdex treat new vessel growth (R3A)?
No, Ozurdex is specifically for macular swelling (M1). Proliferative vessel growth is usually treated with lasers or anti-VEGF injections.
Authority Snapshot
This article discusses the clinical use of corticosteroid implants for diabetic macular oedema in the UK, incorporating current NICE (TA824 and TA301) and NHS standards. The content is written to meet UK medical standards and has been reviewed by the Medical Content Team to ensure alignment with current ophthalmology protocols. Our goal is to help patients understand the role of steroids in their treatment pathway.
