Intravitreal

Detailed article on intravitreal injections

Intravitreal refers to the administration of medication directly into the vitreous humor of the eye. This method is commonly used to treat various retinal diseases and conditions affecting the posterior segment of the eye.

Overview

Intravitreal injections are a critical component in the management of several ocular conditions, including age-related macular degeneration (AMD), diabetic retinopathy, and retinal vein occlusion. The procedure involves the delivery of drugs directly into the vitreous cavity, allowing for high concentrations of medication at the site of pathology with minimal systemic exposure.

Procedure

The intravitreal injection procedure is typically performed in an outpatient setting. The steps involved include:

1. Preparation: The eye is anesthetized using topical anesthetic drops to minimize discomfort. The periocular area is then cleaned with an antiseptic solution, such as povidone-iodine, to reduce the risk of infection.
2. Injection: A fine needle is used to inject the medication into the vitreous cavity. The injection is usually administered in the inferotemporal quadrant of the eye, approximately 3.5 to 4 mm posterior to the limbus.
3. Post-procedure care: Patients are monitored for any immediate complications, such as increased intraocular pressure or endophthalmitis. They are advised to report any symptoms of pain, vision changes, or redness immediately.

Medications Used

Several medications are commonly administered via intravitreal injection, including:

• Anti-VEGF agents: Such as ranibizumab, bevacizumab, and aflibercept, used primarily for neovascular AMD and diabetic macular edema.
• Steroids: Such as triamcinolone acetonide and dexamethasone implant, used for inflammatory conditions and macular edema.
• Antibiotics and antivirals: Used in the treatment of infectious endophthalmitis and viral retinitis.

Complications

While generally safe, intravitreal injections can be associated with complications, including:

• Endophthalmitis: A rare but serious infection of the eye.
• Retinal detachment: Occurs when the retina separates from the underlying tissue.
• Increased intraocular pressure: Can lead to glaucoma if not managed appropriately.

Also see

• Vitreous humor
• Retinal diseases
• Age-related macular degeneration
• Diabetic retinopathy
• Retinal vein occlusion

External links

• American Academy of Ophthalmology: Intravitreal Injection
• National Center for Biotechnology Information: Intravitreal Injections