Intra-Vitreal Steroid Implant
The dexamethasone steroid implant (Ozurdex) is an alternative treatment to the traditional intra-vitreal injection and is FDA-approved for treatment of blurred vision from macular edema (swelling) due to diabetes, retinal vascular occlusion, or non-infectious inflammation of the eye.
The traditional intra-vitreal injections modulate a particular pathway (vascular endothelial growth factor / VEGF) to improve the swelling. For many patients, treatment with this mechanism alone is sufficient. However, in some patients, blurred vision can persist in spite of repeated traditional anti-VEGF treatments due to persistent swelling in the macula that is recalcitrant to the VEGF mechanism.
For these patients, another molecular target is required. Resolving the swelling as soon as possible is crucial to the visual outcome. Persistent swelling causes irreversible damage to the retina's photoreceptors in correlation to its duration of time.
The Ozurdex implant can be offered in these cases to target other inflammatory pathways responsible for the macular edema that are not otherwise affected by traditional anti-VEGF injections. In the most recent NIH-sponsored Diabetic Retinopathy Clinical Research Network (DRCR) trial, the addition of the Ozurdex resulted in a significantly larger percentage of eyes with resolved swelling compared to the group of eyes that did not receive the steroid implant.
The most serious risk is with any type of intra-vitreal injection is infection, which is very rare with reported rates from 1/5,000 to 1/10,000. The warning signs of infection are worsening redness, pain, and/or vision a few days following this injection. If any of these symptoms occur, it is important to return for a check, even if after hours. Cataract can develop in approximately two thirds of patients who have not previously received cataract surgery (see conditions section above) and would be treatable with outpatient surgery (see surgeries section above).
Elevated eye pressure and glaucoma are also risks. Elevated eye pressure can be seen in approximately 28% of patients and most cases can be treated with eye drops before progressing to a diagnosis of glaucoma. Few patients (~1.2%) may require glaucoma surgery to treat persistent elevated eye pressure.
Redness on the white of the eye is a common side effect that can last for 2-4 weeks. Scratchiness/irritation of the eye surface can last for a few hours. Artificial tears / lubricating drops such as Refresh preservative-free are helpful to relieve any surface irritation that may be felt the afternoon/evening following the injection.
Combination of anti-VEGF and steroid offered faster resolution of fluid and improvement in vision for the right patient. Case in point: this patient had profound vision loss due to macular edema (left images). After a combination of anti-VEGF injection (middle images) and Ozurdex (right images) two weeks apart, the patient's vision improved from 20/100 to 20/40 in just one month with reduced retinal swelling at each time point.