Intravitreal Injections
Intravitreal Injection
Intravitreal injection is a specialized medical procedure used to deliver medications directly into the vitreous—the jelly-like substance in the back of the eye. This remains the most effective method for treating various retinal diseases, as it bypasses the blood-ocular barrier that often prevents oral or intravenous medications from reaching the retina in sufficient concentrations.
When You Should Consider Intravitreal Injection
"Wet" Age-Related Macular Degeneration (AMD): To stop the growth of abnormal, leaky blood vessels that cause rapid vision loss.
Diabetic Macular Edema (DME): If you need to reduce retinal swelling caused by fluid leakage from blood vessels damaged by diabetes.
Retinal Vein Occlusion (RVO): To manage fluid backup following a "stroke" in the eye’s vascular system.
Uveitis: Delivering potent anti-inflammatory steroids directly to the back of the eye to treat chronic inflammation.
Endophthalmitis: In emergency cases to deliver immediate antibiotic or antifungal treatment for severe internal infections.
How Is Performed
Numbing: The eye is thoroughly anesthetized using specialized drops or a gel to ensure patient comfort.
Sterilization: The eye and eyelids are cleaned with a povidone-iodine solution to prevent bacterial infection.
Stabilization: A small device (speculum) is used to keep the eyelids open and prevent blinking during the procedure.
Injection: A very fine needle is used to deliver medication through the Pars Plana—the "white part" of the eye—in a process that lasts only a few seconds.
Post-Check: The surgeon checks the eye for immediate pressure changes and may provide artificial tears for comfort.
Duration: The entire clinical process typically takes less than 10 to 15 minutes.
Methods of Injection
Anti-VEGF Therapy: The use of agents that block proteins promoting leaky vessel growth; modern agents often allow for extended treatment intervals of 3–4 months.
Corticosteroid Delivery: Direct injection of steroids to manage chronic internal eye inflammation and swelling.
Antibiotic/Antifungal Administration: Targeted delivery of antimicrobial agents for severe internal infections.
OCT-Guided Treatment: Using high-resolution imaging to determine the precise frequency of injections needed for each patient.
Pre-Procedure Preparation
Baseline Consultation: A detailed exam to identify leaking blood vessels or the specific areas of retinal swelling.
Medical History: Discussing current medications and any history of iodine allergies or recent eye infections.
Visual Expectations: Preparing for the temporary appearance of "floaters" or "bubbles" in your vision immediately following the procedure.
Transportation: Arranging for a ride home, as your vision may be temporarily blurry from dilating drops.
Treatment Planning: Reviewing the long-term schedule, including whether you will receive long-acting medications.
Tests Before Intravitreal Injection
Optical Coherence Tomography (OCT): A high-resolution scan used to measure retinal thickness and track fluid accumulation over time.
Fluorescein Angiography: A diagnostic test used to map out the exact location of leaking blood vessels in the retina.
Visual Acuity Test: Establishing a clear baseline of vision quality to monitor the effectiveness of the medication.
Intraocular Pressure (IOP) Check: Ensuring the internal pressure of the eye is within a safe range before the injection.
Life After Intravitreal Injection
Vision Settling: Expect "floaters" or "bubbles" in your vision to disappear within 24–48 hours as the medication distributes.
Hygiene: Avoid rubbing your eyes or exposing them to swimming pools, hot tubs, or dusty environments for 2 to 3 days.
Injection Site: Monitor for a subconjunctival hemorrhage (a harmless red spot at the needle entry point), which typically resolves within a week.
Safety Monitoring: Watch for rare signs of complication, such as increasing pain, severe redness, or a sudden "curtain" falling over your vision.
Follow-up: Adhering to regular appointments for OCT imaging is essential to ensure the treatment is successfully stabilizing your vision.
Why Specialized Treatment Is Highly Effective
Systemic Safety: Minimizes side effects compared to oral or intravenous medications because the drug stays localized within the eye.
Bypasses Barriers: Delivers high concentrations of medication directly to the retina that other delivery methods cannot reach.
Rapid Results: Offers a quick, outpatient experience with minimal downtime and a fast return to daily activities.
Vision Preservation: Significantly improves or stabilizes vision in patients with conditions that were previously considered untreatable.
Minimal Discomfort: The fine-needle technique is generally described as a sensation of pressure rather than sharp pain.