Anesthesia for Intravitreal Injections
Intravitreal injections, used to treat certain retinal diseases like age-related macular degeneration and diabetic retinopathy, require effective anesthesia for comfort and precise delivery. Anesthesia for intravitreal injections is typically administered by the ophthalmologist due to the low level of anesthesia needed, though in some cases, sedation by an anesthesia provider may be beneficial. Options for this procedure range from topical anesthetics to subconjunctival injections, each chosen based on the patient’s pain threshold, the duration of the procedure, and physician preference.
Topical anesthesia, typically administered as proparacaine or tetracaine drops, is the most common and provides fast, localized numbness with minimal side effects for intravitreal injections. These drops, applied a few minutes before the injection, are easy to use and have a rapid onset, making them ideal for outpatient settings. While effective, they may not provide sufficient anesthesia for all patients, particularly those with low pain tolerance or anxiety. Numbing caused by anesthetic eye drops is surface-level and may not be long-lasting enough for complex procedures 1,2.
For patients requiring a more profound numbing effect, subconjunctival injections are an alternative, delivering anesthetic directly beneath the conjunctiva. This method allows for deeper anesthesia, reducing discomfort for more sensitive patients. However, subconjunctival anesthesia may require greater skill and may cause slight discomfort from the anesthetic injection itself. This technique is typically reserved for patients with heightened anxiety or a particularly low pain threshold 3,4.
Anesthetic gels are also an emerging option. Combining the benefits of topical anesthetics with prolonged numbness, these gels can be applied directly to the ocular surface to create a numbing film. This method provides a longer duration of anesthesia than drops, supporting patient comfort and eliminating the need for multiple anesthetic applications in longer procedures involving intravitreal injections. Gels are particularly useful for patients who need added assurance against discomfort or have difficulty sitting through repeated applications 5–7.
Understanding the specific needs of each patient is critical. Physicians often select anesthetics based on factors such as individual pain tolerance, anxiety levels, and the anticipated duration of the procedure. The careful application of anesthesia allows patients to remain calm and still during intravitreal injections, reducing the risk of eye movement that could interfere with precision and treatment outcomes.
Patient education plays a vital role in managing pain and anxiety. Educating patients on what to expect during anesthesia and reassuring them about the safety and minimal discomfort of the anesthesia can alleviate pre-procedure stress and improve cooperation. Physicians explain that while patients might feel slight pressure or a mild pinch, the anesthesia minimizes sharp pain. The use of calming communication also helps patients relax and improves the overall experience 8,9.
Recent research and technological advancements are likely to further improve anesthesia options for intravitreal injections. Ultimately, effective anesthesia for intravitreal injections is crucial for patient comfort and procedural success, and it is likely to evolve with ongoing innovations in ophthalmic care.
References
1. Han, J., Rinella, N. T. & Chao, D. L. Anesthesia for Intravitreal Injection: A Systematic Review. Clinical Ophthalmology (Auckland, N.Z.) 14, 543 (2020). DOI: 10.2147/OPTH.S223530
2. Chandrasekaran, P. R., Aziz, A. A., Khan, H. & Khanani, A. M. Cooling Anesthesia for Intravitreal Injections – A Review. Clinical Ophthalmology (Auckland, N.Z.) 17, 197 (2023). DOI: 10.2147/OPTH.S388327
3. Kaderli, B. & Avci, R. Comparison of topical and subconjunctival anesthesia in intravitreal injection administrations. Eur J Ophthalmol 16, 718–721 (2006). DOI: 10.1177/112067210601600509
4. Alexander, P., Sahu, D. & Lotery, A. J. Subconjunctival anaesthesia for intravitreal injections. Eye 27, 1109–1109 (2013).
5. AAO 2024: Chloroprocaine ophthalmic gel as anesthesia for intravitreal injections. Ophthalmology Times https://www.ophthalmologytimes.com/view/aao-2024-chloroprocaine-ophthalmic-gel-as-anesthesia-for-intravitreal-injections (2024).
6. https://fyra.io. Patient Assessment: Gel vs Liquid Anesthetic for Intravitreal Injections. Retina Today https://retinatoday.com/articles/2010-apr/patient-assessment-gel-vs-liquid-anesthetic-for-intravitreal-injections.
7. Andrade, G. C. de & Carvalho, A. C. M. de. Comparison of 3 different anesthetic approaches for intravitreal injections: a prospective randomized trial. Arq Bras Oftalmol 78, 27–31 (2015). DOI: 10.5935/0004-2749.20150008
8. How to Give Intravitreal Injections – American Academy of Ophthalmology. https://www.aao.org/eyenet/article/how-to-give-intravitreal-injections.
9. Gomez, J. et al. Strategies for Improving Patient Comfort During Intravitreal Injections: Results from a Survey-Based Study. Ophthalmology and Therapy 5, 183 (2016). doi: 10.1007/s40123-016-0058-2