Eye SchoolUrgent

This site provides general eye-health education. It cannot replace individual assessment by a registered doctor, and does not offer personal diagnosis, prescriptions, bookings, sales or referrals.

If translations differ or are incomplete, the Traditional Chinese (zh-Hant) text on this site prevails.

Retina and macula · B

Intravitreal anti-VEGF injection

Often called 打眼底針 in Hong Kong

Last reviewed: 2026-10-03 · 潘家健醫生

Key points

  • Intravitreal anti-VEGF injections are used for some macular neovascularisation or oedema; suitability is decided after examination.
  • This page covers consent classes and the day-of visit — no sales, no product ranking, no vision guarantee.
  • Worse pain, worse redness or a sudden vision drop after injection: A&E now (rule out endophthalmitis).
  • New flashes or many more floaters without a curtain / sudden blindness: same-day dilated exam when possible.

Anti-VEGF medicine is given into the vitreous for some macular neovascular or oedematous diseases. Whether it is suitable, which Hong Kong-registered product, how often and at what interval, is decided by an ophthalmologist after examination and OCT. This page does not sell or promote any injection and cannot promise better vision.

Anti-VEGF agents discussed in Hong Kong (INN only)

Depending on Hong Kong–registered indications and current supply, a doctor may discuss one or more of the following international nonproprietary names (INNs). Trade names are not listed here, to avoid constituting a medicine advertisement:

INNEducation note
ranibizumabAnti–VEGF-A fragment; one of the large-trial foundations for wet macular disease (see below)
afliberceptVEGF trap; VIEW and related work show dosing options with vision outcomes comparable to monthly ranibizumab
brolucizumabSingle-chain antibody fragment; HAWK/HARRIER noninferior to aflibercept; discuss intraocular inflammation individually, including retinal vasculitis / vascular occlusion risk; after injection, sudden vision drop, many new floaters or a field defect need prompt care (sharp drop / curtain: A&E)
faricimabBispecific (Ang-2 + VEGF-A); TENAYA/LUCERNE explore longer injection intervals

Whether it suits you, which agent, the interval, and public/private supply can only be decided by an ophthalmologist after examination and against Hong Kong registration. Overseas approval ≠ registered or available for you in Hong Kong. This page does not rank which INN is “best”, and it is not a clinic success rate.

Trials elsewhere may use anti-VEGF INNs that are uncommon in Hong Kong practice; those results are class-level reference only and do not mean that medicine should be prescribed here.

Polypoidal choroidal vasculopathy (PCV) (education)

PCV is more common in East Asian / Chinese wet macular disease and often needs tools such as indocyanine green angiography (ICGA) to help distinguish it — not self-labelling. The Asian multicentre EVEREST II randomised trial (JAMA Ophthalmol 2020), in symptomatic macular PCV, compared ranibizumab alone with ranibizumab plus verteporfin photodynamic therapy (vPDT): at 24 months the combination arm had greater vision gain and a higher rate of polyp regression, with a lower median injection count — trial-order figures, not your personal prognosis, and not a product or clinic-success comparison on this site. Whether to inject, which Hong Kong–registered INN, and whether to add PDT are specialist decisions.

Diabetic macular oedema: anti-VEGF class (education)

In centre-involved diabetic macular oedema (DME), the anti-VEGF class versus traditional laser alone can yield better vision outcomes in suitable cases. Large-trial examples include aflibercept in VIVID-DME / VISTA-DME (Korobelnik et al.), and Protocol T comparing several anti-VEGF agents (Wells et al., DRCR) — published trial figures, not personal prognosis or brand comparison. VIEW discusses dosing strategy in wet AMD, not as primary DME evidence. Which INN and interval can only be decided by a doctor against Hong Kong registration and examination.

Procedure (for consent education)

An outpatient injection, usually a few minutes. Asepsis and conjunctival iodine have the strongest evidence for lowering endophthalmitis. This is a class of care, not a pitch for any product.

The order of the day, and the diagrams, are on The day of an intravitreal anti-VEGF injection. The lines above are a consent-style class outline, not instructions to inject yourself.

  1. Confirm the eye, the drug and the history (glaucoma, recent surgery, anticoagulants)
  2. Topical anaesthetic; sometimes a soaked cotton pledget
  3. Speculum; please do not talk or reach up (less droplet contamination)
  4. Dilute povidone-iodine on the conjunctiva and injection site for at least about 30 seconds (some guidance, e.g. in the UK, asks for several minutes) — follow the duty doctor’s sterile protocol. An alternative if iodine-allergic; do not switch to saline yourself
  5. Measure from the limbus: often about 3.5–4.0 mm if the natural lens is present, a little closer (about 3.0–3.5 mm) if there is an implant or no lens; pars plana, avoiding the horizontal rectus
  6. A fine needle, typically about 0.05 mL (follow that product’s instructions)
  7. Check counting fingers or light perception; measure IOP if needed
  8. Follow the review plan. Usual drops can often continue the same day; driving depends on vision

Risks in the literature (per injection or cumulative — not any clinic’s statistics)

EventNote (education; this page’s bibliography does not map each row to a percentage)
Subconjunctival haemorrhageCommon; usually fades in 1–2 weeks
Floaters, foreign-body sensationCommon; vehicle or vitreous strand
Short IOP riseCommon minutes to hours after injection; tell the doctor if you have glaucoma
EndophthalmitisUncommon but an emergency; lifetime risk adds with more injections
Sterile inflammation / endophthalmitis-like reactionUncommon; must be distinguished from infection
Lens touch / cataractUncommon; stay far enough back in a phakic eye
Vitreous haemorrhageUncommon
Retinal tear or detachmentUncommon; curtain or sudden vision drop: A&E. New flashes or more floaters without a curtain or sudden blindness: same-day dilation
Retinal artery occlusionVery rare; sudden blindness is an emergency
  • Repeated injections: some people develop a sustained IOP rise that needs glaucoma-style care
  • Long-term anti-VEGF and macular geographic atrophy are discussed in the literature — a trade-off the doctor weighs, not a reason to stop on your own
  • Labels mention theoretical arterial thrombotic events; large studies on stroke and myocardial infarction disagree. Tell the doctor about cardiovascular disease; do not stop by yourself
  • Pregnancy or planning pregnancy: most products lack adequate data — discuss individually
After injection, worse pain, worse redness or a sudden vision drop (rule out endophthalmitis): go to A&E now; do not wait for a routine clinic slot. A curtain or sudden blindness: go to A&E now. New flashes or a clear increase in floaters without those red flags: dilated fundus exam the same day if possible.

Selected public references (not a full bibliography)

These are the public studies this page draws on. PMID links go to PubMed (US National Library of Medicine) so you can check them. Figures are from those studies — not your prognosis and not a clinic success rate. Links are not a shop.

  1. CATT Research Group, Martin DF, Maguire MG, et al. Ranibizumab and bevacizumab for neovascular age-related macular degeneration. N Engl J Med. 2011;364(20):1897-1908. PMID 21526923比較兩種抗血管內皮生長因子注射的大型試驗（bevacizumab 僅作試驗對照，不是本港選藥表）。本頁不列商品名、不保證視力。
  2. Heier JS, Brown DM, Chong V, et al.; VIEW 1 and VIEW 2 Study Groups Intravitreal aflibercept (VEGF trap-eye) in wet age-related macular degeneration. Ophthalmology. 2012;119(12):2537-2548. DOI 10.1016/j.ophtha.2012.09.006. PMID 23084240VIEW：aflibercept 與每月 ranibizumab 視力結果相若的給藥策略討論。不是商品比較或本港處方保證。
  3. Korobelnik JF, Do DV, Schmidt-Erfurth U, et al. Intravitreal aflibercept for diabetic macular edema (VIVID-DME and VISTA-DME). Ophthalmology. 2014;121(11):2247-2254. DOI 10.1016/j.ophtha.2014.05.006. PMID 25012934VIVID-DME／VISTA-DME：aflibercept 用於糖尿病黃斑水腫。數字是公開試驗結果，不是個人預後或商品比較。
  4. Wells JA, Glassman AR, Ayala AR, et al.; Diabetic Retinopathy Clinical Research Network Aflibercept, bevacizumab, or ranibizumab for diabetic macular edema (Protocol T). N Engl J Med. 2015;372(13):1193-1203. DOI 10.1056/NEJMoa1414264. PMID 25692915Protocol T（DRCR）：比較多種抗 VEGF 用於糖尿病黃斑水腫。數字是公開試驗結果，不是個人預後或商品比較。bevacizumab 為試驗對照語境，不是本港選藥表。
  5. Dugel PU, Koh A, Ogura Y, et al.; HAWK and HARRIER Study Investigators HAWK and HARRIER: Phase 3, Multicenter, Randomized, Double-Masked Trials of Brolucizumab for Neovascular Age-Related Macular Degeneration. Ophthalmology. 2020;127(1):72-84. DOI 10.1016/j.ophtha.2019.04.017. PMID 30986442HAWK/HARRIER：brolucizumab 相對 aflibercept 視力非劣；安全性（包括眼內炎症）須個別討論。不是商品比較。
  6. Heier JS, Khanani AM, Quezada Ruiz C, et al.; TENAYA and LUCERNE Investigators Efficacy, durability, and safety of intravitreal faricimab up to every 16 weeks for neovascular age-related macular degeneration (TENAYA and LUCERNE): two randomised, double-masked, phase 3, non-inferiority trials. Lancet. 2022;399(10326):729-740. DOI 10.1016/S0140-6736(22)00010-1. PMID 35085502TENAYA/LUCERNE：faricimab 延長注射間隔的試驗討論。不是商品比較或本港處方保證。
  7. Lim TH, Lai TYY, Takahashi K, et al.; EVEREST II Study Group Comparison of Ranibizumab With or Without Verteporfin Photodynamic Therapy for Polypoidal Choroidal Vasculopathy: The EVEREST II Randomized Clinical Trial. JAMA Ophthalmol. 2020;138(9):935-942. DOI 10.1001/jamaophthalmol.2020.2443. PMID 32672800亞洲多中心 EVEREST II：有症狀黃斑 PCV，ranibizumab ± 維替泊芬光動力。試驗約數；不是個人預後或商品比較。

This is general medical information, not a diagnosis, and cannot replace an in-person consultation with a registered ophthalmologist, refraction, or a dilated fundus exam. It is not advice to use any medicine or undergo any procedure. Medicines (including off-label use), laser or surgery must be decided by a registered doctor after examination, according to indications and Hong Kong registration. Figures from the literature are published averages, not any clinic’s results. This site does not book, prescribe or refer. Do not change treatment on your own.